JP2017083348A - Ore selection method and device thereof - Google Patents

Abstract

An object of the present invention is to make it possible to accurately select non-defective or defective ores even when the target mineral content is small or good.
An ore sorting device for sorting out ore non-defective products 1a and defective products 1b according to a content ratio of a target mineral, and a supply device 2 for supplying a rock pulverized material 1 so as to be moved along a predetermined movement trajectory w Then, after determining the area of the ore image part based on the imaging device 3 that images the rock crushed material 1 supplied by the supply device 2 in the middle of the movement trajectory w, and the imaging result by the imaging device 3, each ore image By determining the ore non-defective product 1a / defective product 1b by calculating the content ratio of the target mineral in the area of the part and the ore non-defective product 1a / defective product 1b as the spray object, The air spraying device 5 that blows air toward at least a majority region of the projection surface of the spraying object toward the spraying object so as to vary the movement trajectory w of the non-defective product 1a and the defective product 1b.
[Selection] Figure 1

Description

  The present invention relates to an ore sorting method for sorting out ore non-defective / defective products from crushed rocks, and more particularly to an ore sorting method and apparatus for sorting out ore non-defective / defective products during the fall of a rock crushed material.

As a conventional ore sorting method, for example, gold ore as an object to be sorted, the gold ore is crushed and then pulverized to an appropriate particle size, and the obtained ore is suspended in a cyanide aqueous solution. A method of separating and concentrating gold from gangue minerals and sulfide minerals by so-called bluening method that leaches gold, and further separating and concentrating gold minerals from gangue minerals and sulfide minerals by specific gravity flotation and flotation. The method of separating and concentrating gold is used.
However, in order to carry out these methods, the ore has to be pulverized from several tens of microns to several hundreds of microns, which requires enormous energy. In other words, the ore as it is mined contains a lot of host rock mass that contains almost no gold and silver, and pulverizing such host rock into such fine particles consumes much energy. Will do. In addition, since the host rock contains a lot of clay minerals, it is generally well known that clay minerals have an adverse effect on any of the methods of bluening, copper refining, and flotation. It is.

Originally, quartz containing gold and silver is white, and can be easily distinguished from a gray or black mother rock by visual observation. Therefore, as a method of removing the host rock from the coarsely crushed material, automatic sorting by an ore sorter that performs optical inspection and discriminates whether or not the host rock is known is known.
As this type of ore sorting device, as described in, for example, Patent Document 1, an ore containing gold and silver is roughly crushed and an image analysis device connected to a TV camera is used to obtain a white ore surface. A gold ore beneficiation method is adopted in which the portion is calculated and the ratio is less than a predetermined value and is excluded as a host rock.
Here, the target of selection is a fine ore consisting mostly of white quartz, a gray or black mother rock that contains almost no white quartz (slip as a defective ore), and quartz in a vein shape. The so-called single-edged blades are classified into good or defective ores according to the content ratio of the quartz veins.

  Moreover, although the object to be sorted is not an ore, as described in, for example, Patent Document 2, as a grain sorting device, heat from a heater is applied to beans dropped from a shooter, and the temperature distribution of the beans immediately after heating is applied. If the bean is peeled, cracked, or repelled in the beans, the temperature of that part will be higher than the other part. A device for sorting grains with seed coats is disclosed in which the beans that have been dropped are blown off by an ejector toward the defective product collection unit and removed from the good product group.

  Furthermore, as a flying object sorting device, for example, as described in Patent Document 3, an object is conveyed at a high speed by a belt conveyor at a high speed, and then jumped out from a pulley end of the belt conveyor, immediately after the pulley end jumps out. A technique is disclosed in which the quality of an object is selected by changing the trajectory of a falling flight using an air nozzle array in which an image inspection is performed in a horizontal flight state and the determination result is controlled by a solenoid valve.

Japanese Patent Laid-Open No. 5-169036 (Means for Solving the Problems) JP 2004-113904 A (Embodiment of the Invention, FIG. 1) JP 2008-55274 A (Best Mode for Carrying Out the Invention, FIG. 1)

In the above-described Patent Document 1, for example, when a target mineral having a high content ratio is selected as a non-defective ore product, the target mineral region is relatively wide. It is easy to grasp the content of the target mineral, and not only can the content ratio of the target mineral be calculated relatively accurately, but if the air from the air nozzle row is blown to the location corresponding to the target mineral in the ore image, Selection of non-defective or defective products is performed smoothly.
However, when the one with a small target mineral content such as a single blade is selected as a non-defective or defective ore, the area of the target mineral is narrow and the target mineral is selected based on the target mineral area. It is relatively difficult to grasp the entire area of the ore image including it, but it is grasped as multiple ore image parts divided into an ore image part containing the target mineral and an ore image part not containing the target mineral even though it is one ore. It can happen. In such a case, despite the fact that it is originally one ore, there is a concern that one ore image part may be identified as a good ore product and the other ore image part as a defective ore product. There is a possibility that the selection operation of non-defective products or defective products may be performed on one ore.

Further, as disclosed in Patent Document 2, there is a technique in which defective products of a grain are blown away by an ejector according to a result of determining whether the grain is good or bad. In this kind of technology, in the case of light and small things like grain, it is possible to change the trajectory of falling flight sufficiently by blowing air with one ejector on one grain. When the specific gravity is heavy and larger than the grain, it is possible that the ore falling flight trajectory cannot be changed sufficiently by simply blowing air.
In order to eliminate such a situation, for example, as shown in Patent Document 3, by controlling the air nozzle row, the amount of air blown by the air nozzle row is changed according to the size (mass) of the ore, Although it may be possible to change the trajectory of the falling flight sufficiently, it is inaccurate to judge the quality of the ore when sorting the one with few target minerals such as a single blade as a good or bad ore. In the first place, it is not possible to accurately determine whether or not the target is air sprayed by the air nozzle row.
For this reason, when selecting the one with a small target mineral content, such as a single-edged blade, as a good or defective ore product, it is accurately determined whether it is a good or defective ore product, and the identified ore It is necessary to ensure a sufficient amount of air sprayed for any non-defective product or defective product.

  The technical problem to be solved by the present invention is to make it possible to accurately select non-defective products or defective products even when the content of the target mineral is small or good. is there.

  The invention according to claim 1 is configured to move the rock pulverized material along a predetermined movement trajectory when selecting a non-defective product or defective product of the ore predetermined in the content ratio of the target mineral from the rock pulverized material. By separating the ore image portion and the background portion based on the supplying step, the imaging step of capturing the rock crushed material supplied in the supplying step in the middle of the movement trajectory, and the imaging result of the imaging step After determining the area of the ore image part, a discrimination step for discriminating whether the ore is good or defective by calculating the content ratio of the target mineral in the area of each ore image part, and the ore discriminated in the discrimination step Either one of the non-defective product or defective product is used as a spraying object, and air is blown toward the spraying object toward at least a majority region of the projection surface of the spraying object so that the movement trajectory of the non-defective product or defective product varies. By A sorting step of sorting the users, a ore sorting method which includes a.

  The invention according to claim 2 is an ore sorting device that sorts non-defective / defective products of ores that are determined in advance from the crushed rock by the content ratio of the target mineral, and the crushed rock is moved in a predetermined movement path. An ore based on the imaging device for imaging the rock crushed material supplied by the supply device, the imaging device for imaging the rock pulverized material supplied by the supply device so as to move, and the imaging result of the imaging device After determining the area of the ore image part by separating the image part from the background part, and a discrimination device that determines the non-defective / defective article of the ore by calculating the content ratio of the target mineral in the area of each ore image part The spraying object is either a non-defective product or a defective product identified by the discriminating device, and is selected by differentiating the movement trajectory of the non-defective product or defective product. The spraying target An air blowing device blows air to at least a majority area of the projection plane of a mineral sorting apparatus characterized by comprising a.

According to a third aspect of the present invention, in the mineral sorting apparatus according to the second aspect, the determination device includes a first determination unit that determines whether the image is an ore image part or a background part from an imaged result obtained by the imaging instrument, and the first If the distance between adjacent ore image area areas determined by the determination section is within a predetermined set value, the adjacent ore image area areas are combined as one ore, otherwise The content ratio of the target mineral is calculated with respect to the region of the combined portion to be unbonded as another ore and the area of each ore image portion after the processing by the combined portion, and the content ratio of the target mineral is equal to or higher than a predetermined threshold. And a second discriminating unit for discriminating whether the ore is non-defective / defective.
The invention according to claim 4 is the ore sorting device according to claim 2, wherein the discrimination device calculates density information from an imaging result by the imaging instrument, and the density information is used as a target mineral, an ore portion other than the target mineral, and Ternization corresponding to the background part, other than the background part of the ternary image is determined as the ore image part, and the content ratio of the target mineral is calculated from the area occupied by the target mineral with respect to the ore image part of the ternary image Ore sorting device characterized by
The invention according to claim 5 is the ore sorting device according to claim 2, wherein the discriminating device is selected such that a predetermined threshold for the content ratio of the target mineral is less than 50%. It is an ore sorter.
The invention according to claim 6 is the ore sorting device according to claim 2, wherein the imaging instrument is installed on the same side as the air blowing direction by the air blowing instrument, and the first imaging instrument A second imaging instrument capable of imaging from a different direction from the imaging instrument, wherein the discrimination device discriminates an area of the ore image portion based on an imaging result by the first imaging instrument, An ore sorting apparatus that calculates a content ratio of a target mineral contained in the ore image portion with reference to both imaging results obtained by a second imaging instrument.
The invention according to claim 7 is the ore sorting apparatus according to claim 2, wherein when the size of the rock pulverized material is within a range of a predetermined minimum dimension or more and a maximum dimension or less, It is an ore sorter characterized in that nozzles that are individually sprayable and have a diameter smaller than the minimum dimension are arranged side by side so as to intersect the movement trajectory of the spray target with a pitch less than the minimum dimension.
The invention according to claim 8 is the ore sorting apparatus according to claim 2, wherein the air blowing device blows air toward substantially the entire area of the projection surface of the spray object. .
The invention according to claim 9 is the ore sorting apparatus according to claim 2, wherein the air spraying device is arranged in parallel so that nozzles capable of individually blowing air intersect the movement trajectory of the spraying object, An ore sorting device having a plurality of nozzle rows arranged in parallel.

According to the invention which concerns on Claim 1, even when it is a case where the thing with little content rate of a target mineral is used as a good or defective product of ore, the good or defective product of ore can be correctly selected.
According to the second aspect of the invention, there is provided an ore sorting method capable of accurately sorting non-defective or defective ores even if the target mineral content is low or not. Can be embodied as
According to the third aspect of the present invention, it is possible to easily perform the discrimination process for the non-defective product or the defective product as compared with the case where the ternary image processing is not performed as the discrimination device.
According to the invention which concerns on Claim 4, compared with the case where a ternary image process is not performed as a discrimination | determination apparatus, the discrimination | determination process of a non-defective product and a defective product of an ore can be implemented easily.
According to the invention of claim 5, even when the target mineral with a small content ratio is determined to be a good or defective ore, it is possible to accurately select a good or defective ore by simply changing the threshold value by the discrimination device. can do.
According to the invention which concerns on Claim 6, compared with the aspect which uses one imaging device, the content state of the target mineral can be discriminate | determined correctly, and also the operation | movement of air blowing to the spraying target object is stabilized. Can be implemented.
According to the invention which concerns on Claim 7, the spraying of the air by an air spraying tool can be implemented reliably, without affecting the size of a rock ground material.
According to the invention which concerns on Claim 8, even if the magnitude | size of the spraying target object is large to some extent, the spraying force of air and the amount of spraying can fully be ensured.
According to the ninth aspect of the present invention, it is possible to ensure a large amount of air sprayed by the air spraying device as compared with an aspect in which the nozzle row is one row.

It is explanatory drawing which shows the outline | summary of embodiment of the ore sorting method and its apparatus with which this invention was applied. It is explanatory drawing which shows typically the discrimination | determination process C and the selection process D shown in FIG. It is explanatory drawing which shows the whole structure of the ore sorting apparatus which concerns on Embodiment 1. FIG. It is explanatory drawing which shows the principal part of the ore sorting apparatus which concerns on Embodiment 1. FIG. 3 is an explanatory diagram showing a control system of the ore sorting apparatus according to Embodiment 1. FIG. 3 is a flowchart showing an ore sorting process according to the first embodiment. It is a flowchart which shows an example of the quality determination process of the ore of the flowchart shown in FIG. (A) is explanatory drawing which shows typically the 1st discrimination | determination process of the flowchart shown in FIG. 7, or 2nd discrimination | determination processing, (b) is explanatory drawing which shows typically from the coupling | bonding Mr. of the flowchart shown in FIG. is there. (A) is explanatory drawing which shows an example of the picked-up image of an ore with much content rate of a target mineral, and its ternary image, (b) is an image of an ore with a low content rate of target mineral, and its ternary image Explanatory drawing which shows an example, (c) is explanatory drawing which shows an example of the picked-up image of the ore (slack) which hardly contains the target mineral, and an example of its ternary image. (A) is explanatory drawing which shows the behavior of the ore accompanying the blowing of the air by a blowing nozzle, (b) is explanatory drawing which shows typically the blowing operation of the air by the blowing nozzle accompanying the fall of an ore. It is explanatory drawing which shows the principal part of the ore sorting apparatus which concerns on Embodiment 2. FIG. (A) is explanatory drawing which shows an example of the air blowing operation | movement by the 2 row type blowing nozzle used in Embodiment 2, (b) shows the other example of the air blowing operation by the blowing nozzle. Explanatory drawing, (c) is explanatory drawing which shows typically the spraying operation | movement of the air by the 2 row type spray nozzle accompanying the fall of an ore. (A) is explanatory drawing which shows an example of the air blowing operation | movement by the 3 row type spray nozzle used by the deformation | transformation form, (b)-(d) is another of the air blowing operation | movement by the same spray nozzle. It is explanatory drawing which shows an example. (A) is explanatory drawing which shows the behavior of the ore dropped from the belt conveyor in the ore sorting apparatus which concerns on Example 1, (b) is explanatory drawing which contrasted the behavior of the ore at the time of the fall by a belt conveyor system and a vibration feeder system. It is. It is explanatory drawing which shows the relationship between the fall time of the ore which falls from a belt conveyor in the ore sorting apparatus which concerns on Example 1, and the conveyance speed of a belt conveyor. It is explanatory drawing which shows the relationship between the jumping-out amount of the ore falling from a belt conveyor in the ore sorting apparatus which concerns on Example 1, and the conveyance speed of a belt conveyor. It is explanatory drawing which shows the relationship between the rotation amount of the ore falling from a belt conveyor in the ore sorting apparatus which concerns on Example 1, and the conveyance speed of a belt conveyor. It is explanatory drawing which shows the simulation of the fall locus | trajectory of the ore from the conveyor front-end | tip in each conveyance speed of the belt conveyor (roll diameter: 200 mm) used in Example 1. FIG. It is explanatory drawing which shows the simulation of the fall locus | trajectory of the ore from the conveyor front-end | tip in each conveyance speed of the belt conveyor (roll diameter: 300 mm) used in Example 1. FIG. It is explanatory drawing which shows the change of the flight distance accompanying the difference in the air blowing conditions in the ore sorting apparatus which concerns on Example 2. FIG.

Outline of Embodiment FIG. 1 shows an outline of an embodiment of an ore sorting method and apparatus to which the present invention is applied.
In the figure, the ore sorting method is performed by sorting the rock pulverized material 1 from the rock pulverized material 1 in advance to select the non-defective product 1a and the defective product 1b of the ore predetermined by the content ratio of the target mineral. The ore image section based on the supply process A that is supplied so as to be dropped in the image, the imaging process B that images the rock crushed material 1 supplied in the supply process A in the middle of the movement trajectory w, and the imaging results of the imaging process B After determining the region of the ore image part by separating the background and the background part, the discrimination process C for discriminating the non-defective product 1a and the defective product 1b of the ore by calculating the content ratio of the target mineral in the region of each ore image part One of the ore non-defective product 1a and the defective product 1b determined in the determination step C is set as a spraying object (in FIG. 1, the ore non-defective product 1a is exemplified), and the spraying object is directed toward the spraying object. In at least a majority of the projection plane Blowing air (in this example w1, w2) movement trajectory w ore good 1a · defective 1b is obtained and a sorting step D of selecting both by varying the.

In this example, the selection method of the non-defective product 1a / defective product 1b is that the threshold value of the content ratio of the target mineral in the ore is determined in advance, the ore above the threshold value as the non-defective product 1a, and the ore below the threshold value as the defective product 1b It is what is selected.
Here, the supply process A may be appropriately selected as long as it is a process of supplying the rock ground material 1 so that the rock ground material 1 moves along a predetermined movement trajectory. For example, a method of transporting rock crushed material on a belt conveyor and flying it in a substantially horizontal direction from the end of the belt conveyor, a method of dropping in a substantially vertical direction from the end of the belt conveyor, or an inclined sliding rod A method of sliding and flying from the tip of the sliding kite may be used as appropriate.
Moreover, as the imaging process B, any process may be used as long as the rock pulverized material 1 is captured as an image using the imaging instrument 3 in the middle of the movement trajectory w. Also good.

Further, as the discrimination step C, the rock pulverized product 1 discriminates the non-defective product 1a / defective product 1b based on the imaging result. As shown in FIG. What is necessary is just to perform the “discriminating process from the part Sc” and the “discriminating process of the non-defective product 1a / defective product 1b by calculating the content ratio of the target mineral Sa in the region of the ore image part Sb”. Here, for the content ratio of the target mineral Sa, for example, the content area (or the number of pixels) of the target mineral Sa in the region of the ore image portion Sb is obtained, and the total area (or pixel) corresponding to the size of the ore image portion Sb is obtained. The ratio (Sa / Sb) to the number) may be obtained.
In this example, since the content ratio of the target mineral Sa is calculated after the ore image portion Sb is specified in the discrimination step C, the one with a small content ratio of the target mineral is regarded as a good ore product 1a. Even so, the non-defective product 1a and the defective product 1b are accurately determined. For example, when the content of the target mineral Sa is high as the non-defective ore 1a, the region of the ore image portion Sb may be determined centering on the distribution of the target mineral Sa, and the content ratio may be calculated. In the case where the one with a small content of Sa is a good ore 1a, when trying to determine the ore image portion Sb centering on the distribution of the target mineral Sa, the vein-shaped target mineral Sa is distributed in one ore. In such a case, the ore image portion Sb may be divided into a plurality of parts, and in this case, the non-defective product 1b is obtained for one ore image portion and the defective product 1b is obtained for the other ore image portion. As described above, there is a concern that different quality judgments may be made for one ore.

In addition, the sorting step D is a step of sorting the ore non-defective product 1a / defective product 1b. As shown in FIG. 2, the ore non-defective product 1a or defective product 1b is used as the spray target Tg, and the spray target As an operation of blowing air onto Tg, it is sufficient that the blowing area Bw blows air toward at least a majority area of the projection surface of the blowing object Tg. In this example, it is preferable to ensure a large area for blowing air as much as possible for the spray target Tg, and at least a majority region of the projection surface of the spray target Tg is used as a requirement.
In this case, the spray target Tg may be appropriately selected as the non-defective product 1a or the defective product 1b, but it is related to which ratio is higher in the selection target, and the lower ratio is selected. It is preferable to make it a spray target. The reason for this is that the smaller the ratio of the objects to be sprayed, the smaller the amount of air sprayed, which makes it possible to reduce the load on the compressor for air compression.

As shown in FIG. 1, the ore sorting device embodying the ore sorting method sorts the ore non-defective product 1a and defective product 1b determined in advance from the crushed rock 1 by the content ratio of the target mineral. The apparatus is a device for supplying the rock pulverized material 1 so as to move the rock pulverized material 1 with a predetermined movement trajectory w, and the movement trajectory of the rock pulverized material 1 supplied by the supply device 2. After determining the area of the ore image part by separating the ore image part and the background part based on the image pickup device 3 picked up in the middle of w and the imaging result by the image pickup tool 3, within the area of each ore image part The discrimination device 4 that discriminates the non-defective product 1a / defective product 1b by calculating the content ratio of the target mineral, and the either ore good product 1a / defective product 1b determined by the discriminating device 4 is sprayed. And ore good product 1a, defective product 1 An air blowing device 5 that blows air toward at least a majority region of the projection surface of the spraying object toward the spraying object so as to select both by changing the movement trajectory w (w1, w2 in this example) , With.
In FIG. 1, the supply device 2 adopts a system in which the rock pulverized material 1 is transported by a belt-shaped transport body 6 such as a belt conveyor and flies in a substantially horizontal direction from the end of the belt-shaped transport body 6. Further, reference numeral 7 denotes a sorting container for sorting and storing the good ore 1a or defective 1b. For example, the receiving area R1 for the good ore 1a and the receiving area R2 for the ore defective 1b are used as partition walls. The structure is partitioned.

In such technical means, the discriminating device 4 may be any device that discriminates a non-defective product or a defective product of the ore using the discriminating method described above based on the imaging result of the imaging device 3.
Moreover, as the air spraying instrument 5, the rock pulverized material 1 moved to the downstream side in the moving direction of the rock pulverized material 1 from the imaging position Q1 is used as the spraying target, and the spraying direction may be a direction that intersects the moving direction. . Here, the air spraying position Q2 only needs to be set at a certain distance from the imaging position Q1, and the air spraying operation by the air spraying device 5 takes into consideration the moving speed of the rock ground material, and the rock ground material 1 What is necessary is just to start it after progress for a fixed time after passing the imaging position Q1.

Next, a typical aspect or a preferable aspect of the ore sorting apparatus in the present embodiment will be described.
First, as a preferable aspect of the discriminating device 4, a first discriminating unit that discriminates an ore image part or a background part from an imaging result obtained by the imaging instrument 3, and an adjacent ore image part discriminated by the first discriminating unit. If the distance between the areas is within a predetermined set value, the adjacent ore image area areas are combined as one ore, and otherwise the unbound as another ore The content ratio of the target mineral is calculated for each of the ore image areas after processing according to the above, and a non-defective product or defective product of the ore is discriminated depending on whether the content ratio of the target mineral is equal to or higher than a predetermined threshold value. And a determination unit.
In this case, the first discriminating unit discriminates between the ore image part and the background part. For example, when the target mineral of the ore is close to white and the area other than the target mineral is close to black, it is originally one ore. However, a situation may occur in which the images are displayed separately in a plurality of ore image portions. At this time, if the plurality of ore image portions are uniformly determined as individual ores, depending on the distribution of the target mineral, there is a possibility that the same ore is discriminated from a non-defective product or a defective product. For this reason, in this example, if the distance between the areas of the adjacent ore image parts is within a predetermined set value (x ₀ , y ₀ ), the process of combining both areas as one ore is performed. The ore image portion corresponding to each ore is determined. For each ore image part determined in this way, the content ratio of the target mineral is calculated by the second discrimination part to discriminate between the non-defective product and the defective product of each ore.
Here, in the processing of the joint portion, for example, an area surrounded by a circumscribed rectangle of the ore image portion is used as the region of the ore image portion, and the setting values (x ₀ , y ₀ ) of the joint portion are a plurality of adjacent ores. What is necessary is just to select beforehand as a parameter | index which shows that an image part is one ore, for example, the value approximated to (0, 0) or 0 is used.

As another preferred mode of the discriminating device 4, grayscale information is determined from the imaging result obtained by the imaging device 3, and the grayscale information is ternized corresponding to the target mineral, the ore portion other than the target mineral, and the background portion. A mode in which a portion other than the background portion of the binarized image is determined as the ore image portion, and the content ratio of the target mineral is calculated from the area occupied by the target mineral with respect to the ore image portion of the ternary image.
In this example, the grayscale information obtained from the imaging result obtained by the imaging device 3 is used, and it is ternarized so as to be divided into three regions of the target mineral, the ore portion outside the target mineral, and the background portion, and the ternary image is labeled. In this way, the content ratio of the target mineral with respect to the ore image part and the ore image part is obtained.
Furthermore, another preferred embodiment of the discriminating device 4 includes one in which a predetermined threshold for the content ratio of the target mineral is selected as a value less than 50%.
When the pulverized rock 1 is coarsely pulverized to some extent, even if the ore has a low content ratio of the target mineral, it may not be said that the content of the target mineral is so small because the size of the ore is large. In this case, the present aspect is intended to select the quality of the ore in a wider range by setting a low threshold value as a criterion for determining the quality of the ore.

Moreover, in order to raise the imaging accuracy by the imaging device 3, the direction different from the 1st imaging device and the 1st imaging device installed as the imaging device 3 on the same side as the blowing direction of the air by the air blowing device 5 is different. The discriminating device 4 discriminates the region of the ore image part based on the imaging result of the first imaging instrument, while the first and second imaging instruments both A mode in which the content ratio of the target mineral contained in the ore image portion is calculated with reference to the imaging result is preferable.
In this example, since the rock pulverized material 1 can be imaged from a plurality of directions, the content ratio of the target mineral contained in the rock pulverized material 1 can be confirmed from a plurality of directions. However, since the air blowing operation by the air blowing device 5 is determined by the arrangement position of the air blowing device 5, the size determination of the area of the ore image portion is the same as the air blowing direction by the air blowing device 5. The imaging result obtained by the first imaging instrument provided on the side is decided to be used.

Moreover, as a typical aspect of the air spraying device 5, when the size of the rock pulverized material 1 is within a range between a predetermined minimum dimension and a maximum dimension, the air spraying device 5 can spray air individually. And the aspect which arranges in parallel so that the nozzle of diameter smaller than a minimum dimension may cross | intersect the movement locus | trajectory of a spraying target object with the pitch below a minimum dimension is mentioned. When the size of the rock pulverized material 1 is determined within a predetermined range by sieving, when selecting the air spraying device 5, nozzles having a diameter smaller than the minimum dimension intersect the movement trajectory of the spraying object at a pitch less than the minimum dimension. Thus, even if it is the rock pulverized material 1 of the minimum dimension, it is possible to blow air.
Furthermore, as a preferable aspect of the air blowing device 5, from the viewpoint of sufficiently securing the blowing force and the blowing amount of air, air is directed toward substantially the entire area of the projection surface of the blowing object Tg (see FIG. 2). The thing to spray is mentioned.
Furthermore, as a preferable aspect of the air spraying device 5, nozzles that can be individually sprayed with air are arranged side by side so as to intersect the movement trajectory of the object to be sprayed, and a plurality of nozzle rows arranged in parallel are provided. Can be mentioned. In this example, the nozzle row has a plurality of stages, but the air blowing timing of the nozzles in each row may be the same or different. Moreover, the spraying direction may be parallel, or it may be sprayed concentrated on one place as non-parallel.

Hereinafter, the present invention will be described in more detail based on embodiments shown in the accompanying drawings.
Embodiment 1
-Overall configuration of ore sorting device-
FIG. 3 is an explanatory diagram showing the overall configuration of the ore sorting apparatus according to the first embodiment.
In the figure, the ore sorting device 20 has a storage container 21 in which a crushed rock containing ore (for example, gold ore) to be selected is stored, and the crushed rock is predetermined in the storage container 21. A sieve 22 for adjusting the size, for example, a maximum diameter size of 50 to 75 mm, is attached, and a water washing device (not shown) is attached. Only the crushed rock of the size of the range is passed.
In this example, a vibration feeder 23 is disposed below the sieve 22 of the storage container 21, and a belt conveyor 25 is disposed on the downstream side of the vibration feeder 23 via a guide chute 24. .

In the present embodiment, the belt conveyor 25 is, for example, a belt in which a conveyor belt 26 is circulated between a pair of tension rolls 27 and 28 so as to be able to circulate. Is a drive roll that can transmit the circulatory belt, and the conveyor belt 26 is circulated and moved.
In this example, the conveyor belt 26 is formed using a thick wear-resistant belt material (for example, elastic rubber such as ethylene or propylene containing a reinforcing material such as a steel cord or a nonwoven fabric) that can convey the rock crushed material G. Since the surface portion is provided with an appropriate frictional resistance, the crushed rock G introduced via the guide chute 24 is held and transported at an appropriate interval without unnecessarily rolling. It is like that.
In this example, the belt conveyor 25 is adjusted by the drive motor 29 so as to convey the conveyor belt 26 at a predetermined speed vc.
In FIG. 3, the rock pulverized product G is placed on the belt conveyor 25 within a predetermined allowable width dimension. The rock pulverized product G has a non-defective Ga of the ore to be selected (in the figure). And a defective product Gb (denoted by ● in the figure) called a so-called shear. Details of the discrimination criteria for the non-defective Ga and defective Gb of the ore here will be described later.

Further, as shown in FIGS. 3 and 4, the belt conveyor 25 drops the rock crushed material G to a predetermined drop from the tip portion of the portion that is stretched over the stretching roll 28 at the downstream end of the conveying belt 26 in the conveying direction. It is made to fall along the locus (movement locus) w.
A camera 30 as an imaging tool is disposed in a substantially horizontal direction at a portion facing the imaging position Q1 located in the middle of the fall trajectory w of the rock crushed material G, and further, in the vicinity of the camera 30. Are provided with one or a plurality of illumination lamps 40 for illuminating the imaging position Q1.
Further, a nozzle array 51 that is an element of the air spraying device 50 is disposed in a part of the fall trajectory w of the crushed rock G that faces the spraying position Q2 located below the imaging position Q1.
Furthermore, below the spray position Q2 on the fall trajectory w of the crushed rock G, a sorting container 70 for sorting and storing the non-defective Ga and defective Gb of the ore to be sorted is installed.
Reference numeral 80 denotes a control device that sends predetermined control signals to the camera 30, the illumination lamp 40, the air blowing device 50, and the drive motor 29 to control each element.

<Selection of conveyor speed for belt conveyor>
In the present embodiment, the transport speed vc of the belt conveyor 25 (specifically, the transport belt 26) is selected as follows.
In this example, the tension roll 28 positioned downstream in the conveyance direction of the belt conveyor 25 has a diameter d, and the conveyance belt 26 is stretched over the tension roll 28 having the diameter d and is arranged in a curved manner in a semicircular cross section. Yes.
Here, the crushed rock G is placed and conveyed on a linear portion 26a extending in the horizontal direction of the conveyor belt 26 of the belt conveyor 25, and is horizontally aligned at a site from the linear portion 26a to the curved portion 26b of the conveyor belt 26. To be released.
At this time, if the conveyance speed of the conveyance belt 26 is set to be faster than a predetermined threshold, the discharge speed of the rock pulverized material G in the horizontal direction is increased, and the rock pulverized material G is separated from the curved portion 26 b of the conveyance belt 26. I will fly in. In this case, although the fall trajectory w of the rock pulverized product G varies depending on the difference in particle size (weight), it can be obtained as a relatively stable one. However, if the discharge rate of the rock pulverized product G in the horizontal direction is too high. The horizontal flight distance of the rock crushed material G becomes large, and accordingly, it is necessary to secure the installation space for the camera 30 and the air blowing device 50 at a position sufficiently away from the belt conveyor 25. There is a concern that the size of the sorting device 20 may increase.
On the other hand, when the conveyance speed of the conveyance belt 26 falls below a predetermined threshold value, the rock crushed material G is conveyed in contact with the conveyance belt 26 until reaching the drop start position corresponding to the tip position of the curved portion 26b of the conveyance belt 26. When the transport speed of the transport belt 26 becomes extremely slow, the rock crushed material G slides at the contact portion with the curved portion 26b of the transport belt 26, and the rock crushed away from the transport belt 26. The falling start position of the object G varies, or the crushed rock G that has been slid and rolled on the curved portion 26b, and the falling start posture of the crushed rock G that is separated from the conveyor belt 26 varies, and the crushed rock There is a concern that the fall trajectory w of G tends to be unstable.
Therefore, in the present embodiment, at the curved portion 26b of the conveyor belt 26, the rock crushed material G draws a falling trajectory w having a curvature close to the curvature of the peripheral surface of the curved portion 26b, and slips at the contact portion with the curved portion 26b. The transport speed of the transport belt 26 is selected to be a predetermined transport speed vc so that the transport belt 26 is transported without being moved.
Specific examples of selection will be described in detail in the examples.

<Camera>
In the present embodiment, as shown in FIGS. 3 to 5, the camera 30 is configured by a line sensor in which imaging elements 31 such as monochrome CCDs are arranged along a horizontal direction at a predetermined pixel density interval k. The rock crushed material G falling at the position Q1 is sequentially imaged.
In this example, the camera 30 has an imaging position Q1 that is lower by h0 in the vertical direction from the horizontal position along the linear portion 26a of the conveyor belt 26 of the belt conveyor 25, and the rock crushed material G that crosses the imaging position Q1. Imaging information including the projected area and the density information of the crushed rock G is acquired. In this example, the selection object is gold ore, and gold as the target mineral is an image close to white in a monochrome image, so that it is close to white in the grayscale image within the projected area of the rock crushed material G. The ratio occupied by the image portion is the content ratio of the target mineral, and it is possible to determine whether the ore is non-defective or defective according to whether the content ratio is equal to or greater than a predetermined threshold.

<Air spray appliance>
In the present embodiment, as shown in FIGS. 3 to 5, the nozzle array 51, which is an element of the air blowing device 50, extends from the horizontal position along the straight portion 26 a of the conveyor belt 26 of the belt conveyor 25 in the vertical direction. h1 (h1> h0) is arranged opposite to the lower blowing position Q2, and a plurality of blowing nozzles 52 are arranged at a predetermined pitch interval p over a substantially horizontal direction. The on / off control is performed by the corresponding electromagnetic valves 53.
Here, the inner diameter u and the pitch interval p of the spray nozzle 52 may be appropriately selected. However, from the viewpoint of maintaining good air blowing to the rock pulverized material G, the minimum size of the rock pulverized material G ( In this example, it may be set smaller than 50 mm), and for example, it is set to about 8 to 20 mm (in this example, all are around 10 mm).
In this example, assuming that the nozzle array 51 has, for example, n spray nozzles 52 arranged in a line, the solenoid valves 53 corresponding to each spray nozzle 52 are divided into a plurality of stages (in this example, four stages). Are configured as solenoid valve units 54 arranged n / 4 each. And the air tank 55 in which the compressed air pressurized to predetermined pressure (for example, 0.7-1.0 MPa) is stored is provided, and this air tank 55 is connected to the flow path of each solenoid valve 53. The compressed air of the air tank 55 is supplied to the corresponding blowing nozzle 52 in accordance with the ON operation of the corresponding electromagnetic valve 53, and the blowing operation of the air by the blowing nozzle 52 is performed.
Each electromagnetic valve 53 is configured to generate an on / off signal from an electromagnetic valve driving circuit 56, and a control signal from a control device 80 is sent to the electromagnetic valve driving circuit 56.
In particular, in this example, when the control device 80 determines that the rock pulverized material G is a non-defective Ga from the imaging results of the camera 30, the control device 80 responds at the timing when the non-defective Ga of the ore passes the spray position Q2. The electromagnetic valve 53 is turned on, and the air blowing operation by the corresponding blowing nozzle 52 is performed.

<Selection container>
In the present embodiment, as shown in FIGS. 3 and 4, the sorting container 70 has a storage area for the non-defective Ga and defective Gb of the ore from the spray position Q2 by h2 in the vertical direction (in this example, the first Storage region R1 is used as a non-defective product Ga and second storage region R2 is used as a storage region for defective products Gb), and each storage region R1, R2 is located substantially directly below the spraying position Q2. Has a partition wall 71 for partitioning.
Here, when the non-defective Ga of the ore is sprayed along with the air blowing operation by each of the spray nozzles 52, the non-defective Ga of the ore falls on a fall trajectory w1 different from the drop trajectory w2 of the defective Gb. However, as the falling trajectory w1 of the non-defective Ga of the ore, it is sufficient that the amount of projection j from the partition wall 71 is sufficiently secured so that the non-defective Ga is reliably accommodated in the determined accommodation region R1. The distance h2 from the spray position Q2 to the sorting container 70 may be selected so that the jump amount j is sufficiently secured.

-Ore sorting process-
In the present embodiment, the control device 80 has an ore sorting process program (see FIG. 6) that can sort out the non-defective Ga and defective Gb from the crushed rock G, and by executing this program. In addition, the selection of the non-defective product Gb and the defective product Gb is performed.
Now, as shown in FIGS. 3 and 6, when a start switch (not shown) is turned on, the ore sorting device 20 is operated, and the rock pulverized material G is passed through the sieve 22 while being washed with water in the containing container 21, and is within a predetermined range. Then, the crushed rock G is supplied onto the belt conveyor 25 through the vibration feeder 23 and the guide chute 24.
At this time, the belt conveyor 25 is transported at a predetermined transport speed vc, and the rock crushed material G on the belt conveyor 25 is transported at a predetermined transport speed vc and is stretched downstream in the transport direction of the belt conveyor 25. It falls while drawing a fall trajectory w having a curvature close to the curvature of the peripheral surface of the curved portion 26b of the conveyor belt 26 along the gantry roll 28.

Then, when the rock crushed material G passes through the imaging position Q1, the camera 30 images the rock crushed material G in a state of being illuminated by the illumination light from the illumination lamp 40.
Here, as the captured image from the camera 30, for example, as shown in FIGS. 9A to 9C, an image displayed at a gray level of multiple gradations (for example, 256 gradations) is obtained.
In other words, the captured image from the camera 30 displays the ore image portion and the background portion as the rock crushed material G, and the target mineral is appropriately distributed in the region of the ore image portion. In this example, since the quartz containing gold, which is the target mineral, is white, among the ore image portions, the white or near white image portion is the target mineral, and the other gray or black image portions are the other. It is understood that it is a part other than the target mineral and the background part is black.
In FIG. 9, (a) is an example of an image of an ore with a high content of the target mineral, (b) is an example of an image of an ore with a low content of the target mineral, and (c) is an image of the target mineral. The example of a picked-up image of no gap is shown.

In this state, the control device 80 discriminates a non-defective product Ga or a defective product Gb for the crushed rock G based on the imaging result from the camera 30.
In this example, as shown in FIG. 7 and FIGS. 8A and 8B, as a method for determining the quality of the ore, a first determination process for determining whether the ore image portion Sb or the background portion Sc is obtained from the imaging result of the camera 30. If the distance between adjacent ore image portions Sb determined in the first determination processing is within a predetermined set value, the adjacent ore image portions Sb are combined as one ore, Otherwise, the content ratio of the target mineral Sa is determined in advance by calculating the content ratio of the target mineral Sa with respect to the region of each of the ore image portions Sb after the combined processing that is not combined as another ore. A second discriminating process for discriminating whether the ore is non-defective or defective according to whether or not it is equal to or higher than the threshold value α, and a method is used that is continuously performed until the discrimination of all ores is completed.
In the present example, in determining whether ore is good or bad, multi-gradation (for example, monochrome gradation 8 bits) light / dark information is determined from the imaging result of the camera 30, for example, as shown in FIGS. 9 (a) to 9 (c). In addition, the density information is ternarized by a predetermined threshold corresponding to the target mineral, the ore portion other than the target mineral, and the background portion, and as shown in FIG. 8A, the background portion Sc of the ternary image is displayed. Is used as the ore image portion Sb, and the content ratio of the target mineral is calculated from the area occupied by the target mineral Sa with respect to the ore image portion Sb of the ternary image.

Here, it supplements about a joint process.
In this example, the first discrimination process determines whether the ore image portion Sb or the background portion Sc. For example, as shown in FIG. 9B, a pulse-like target mineral Sa is formed in the region of the ore image portion Sb. Is contained in a small ratio and the vein-shaped target mineral Sa is arranged so as to divide the region of the ore image portion Sb, for example, as shown in FIG. Although it is an ore, a situation may occur in which it is displayed separately in a plurality of ore image portions Sb (Sb ₁ and Sb _{2 in the} figure).
At this time, if the plurality of ore image portions Sb are uniformly determined as individual ores, there is a possibility that the same ore is discriminated from a non-defective product or a defective product. For this reason, in this example, as shown in FIG. 8 (b), the dotted line in the figure surrounded by the circumscribed rectangle of the ore image portion Sb as the region of the adjacent ore image portions Sb (Sb1, Sb2) as the combining process When the distance between these circumscribed squares is within a predetermined set value (x ₀ , y ₀ ), the region M (M ₁ , M ₂ ) shown in FIG. While the region U is set as the region of the ore image part, when the distance between the circumscribed rectangles described above exceeds a predetermined set value (x ₀ , y ₀ ), the processing is performed in which both are separated and are treated as separate ores. Is called.
Note that the set value (x ₀ , y ₀ ) of the combination process may be selected in advance as an index indicating that a plurality of adjacent ore image portions Sb (Sb ₁ , Sb ₂ ) are one ore. , 0) or a value approximating zero.

Then, in the second discrimination process, the non-defective product / defective product of each ore is discriminated by calculating the content ratio of the target mineral Sa from the following formula for each ore image portion Sb thus determined. .
(Sa / Sb) ≧ α (Formula 1)
Here, α is a threshold value indicating a ratio (for example, 30%) that allows the ore to be good Ga.
In this example, as described above, a method of calculating the content ratio of the target mineral Sa from the area occupied by the target mineral Sa with respect to the ore image portion Sb of the ternary image is used. In this case, since the target mineral Sa is the white region and the ore image portion Sb is the entire ore including the target mineral Sa and is the white region and the gray region, Sa / Sb = (white region) / (white region + gray region) Calculated.
For example, in the case shown in FIG. 9A, the condition (Sa / Sb) ≧ α is satisfied, and the crushed rock G is determined to be a good ore Ga.
Further, in the case shown in FIG. 9B, the crushed rock G is discriminated as a non-defective Ga or defective Gb depending on whether or not the condition of (Sa / Sb) ≧ α is satisfied.
Further, in the case shown in FIG. 9C, since (Sa / Sb) <α, the crushed rock G is determined as a defective ore Gb.

Next, when the control device 80 determines, for example, that the rock pulverized material G is a good ore Ga, based on the imaging result of the camera 30, at the timing when the good ore Ga passes through the spray position Q2. Corresponding spray nozzles 52 blow air against the fine ore Ga.
At this time, the imaging position Q1 and the spraying position Q2 have different falling speeds of the good ore Ga, but since the distance between them is constant, the ore good Ga that has passed the imaging position Q1 reaches the spraying position Q2. The drop time until this is fixed, and based on this, the air blowing operation timing by the blowing nozzle 52 is determined.
In this example, as shown in FIG. 6, the control device 80 performs the air blowing condition so as to perform the air blowing operation by the corresponding blowing nozzle 52 on the non-defective Ga of the ore passing the blowing position Q2. Then, a control signal is generated based on the air blowing condition.
When the ore non-defective Ga drops now facing the nozzle array 51, the control device 80 recognizes the falling movement position of the ore non-defective Ga passing through the spraying position Q2, and the time shown in FIG. With the passage of time (t = Δt → 6Δt), an air blowing operation is performed by the blowing nozzle 52 at a position corresponding to the non-defective Ga. In FIG. 10 (b), the ◯ spray nozzle 52 indicates that air is not sprayed, and the ● spray nozzle 52 indicates that air is being sprayed.
When such an air blowing operation by the spray nozzle 52 is performed, compressed air is blown over substantially the entire projection surface facing the gravity direction of the non-defective product Ga, and the partition wall 71 of the sorting container 70 is sprayed. Are accommodated in the second accommodation region R2 via a drop trajectory w2 having a sufficient pop-out amount j. In this example, compressed air is blown over substantially the entire projection surface facing the direction of gravity of the good ore Ga, but if the compressed air is blown over the majority of the projection surface described above, The ore sorting operation can be carried out satisfactorily.
In addition, since the blowing operation of the air by the spray nozzle 52 is not performed for the ore defective product Gb, the ore defective product Gb passes through the fall trajectory w2 that is continuous with the predetermined fall trajectory w2. It is accommodated in the accommodation area R2.

In the present embodiment, as shown in FIG. 10A, the spray nozzle 52 blows air against the falling ore non-defective Ga while rotating in the M direction. However, when it reaches a posture in which the upper side of the non-defective Ga is inclined so as to be closer to the spray nozzle 52 side than the lower side, when the air from the spray nozzle 52 is blown to the non-defective Ga, In addition to the spraying force component Fh that pushes to the top, the upwardly directed spraying force component Fv is given. At this time, the upward spraying force component Fv acts on the non-defective Ga, so that a resistance force when the non-defective Ga falls is generated, and accordingly, the falling time of the non-defective Ga can be earned. It is possible to ensure a large flight distance of the non-defective Ga that accompanies the spraying.
Further, in the present embodiment, the ore that is the rock pulverized material G that has fallen from the belt conveyor 25 exhibits a behavior in which gravitational acceleration acts as it falls and is scattered in the falling direction. For this reason, the amount of rock crushed material G supplied onto the belt conveyor 25 may be varied so that the rock crushed material G does not overlap, and is distributed on the belt conveyor 25 as in the case of adopting the horizontal flight method. It is not necessary to supply the crushed rock G in the state.

In the present embodiment, one camera 30 is installed on the same side as the air blowing direction by the air blowing device 50, but the present invention is not limited to this and is different from the camera 30. One or a plurality of other cameras (not shown) that can be imaged from the direction are installed, and the area of the ore image portion Sb is determined based on the imaging result of the camera 30, while the imaging results of both the camera 30 and the other camera Of course, the content ratio of the target mineral Sa included in the ore image portion Sb may be calculated more. In this example, since the content ratio of the target mineral Sa included in the ore image portion Sb can be confirmed from a plurality of directions, the calculation is performed by appropriately correcting the content ratio of the target mineral Sa included in the ore image portion Sb. Accuracy can be increased.
For example, when two cameras are installed, if both the camera 30 and another camera (not shown) that captures images from the opposite side of the camera 30 are installed, both sides of the ore are installed at the same angle. This is preferable in that the content ratio of the target mineral Sa can be calculated in a state where the region of the ore image portion Sb to be discriminated is made common.

Embodiment 2
FIG. 11 is an explanatory diagram showing a main part of the ore sorting apparatus according to the second embodiment.
In the figure, the basic configuration of the ore sorting apparatus 20 is substantially the same as that of the first embodiment, but includes an air blowing device 50 different from that of the first embodiment. Components similar to those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and detailed description thereof is omitted here.
In this example, the air blowing device 50 has two upper and lower nozzle arrays 51a and 51b. In each nozzle array 51a and 51b, the blowing nozzles 52 are arranged at predetermined pitch intervals.
In the present embodiment, the upper and lower two-stage nozzle arrays 51a and 51b are configured to simultaneously perform the air blowing operation by the blowing nozzles 52 in each row as shown in FIG. 12 (a) (simultaneous striking method). Alternatively, as shown in FIG. 12B, a mode (time difference impact method) in which the air blowing operation by the blowing nozzles 52 in each row is performed with a time difference may be employed.
In this example, when the ore non-defective Ga drops now facing the nozzle arrays 51a and 51b, the control device 80 recognizes the falling movement position of the ore non-defective Ga passing through the spraying position Q2. As the time elapses (t = Δt → 6Δt) in FIG. 12C, the air is sprayed by the spray nozzle 52 at a position corresponding to the non-defective Ga. In FIG. 12C, the ◯ spray nozzle 52 indicates that air is not sprayed, and the ● spray nozzle 52 indicates that air is being sprayed.
When such an air blowing operation by the spray nozzle 52 is performed, the ore non-defective Ga is sprayed by about twice the compressed air as compared with the first embodiment, and further from the partition wall 71 of the sorting container 70. It is accommodated in 1st accommodation area | region R1 through the fall locus | trajectory w1 with sufficient jumping amount j.

In the present embodiment, the upper and lower nozzle arrays 51a and 51b are used as the air blowing device 50, but the present invention is not limited to this, for example, as shown in FIG. The nozzle arrays 51a to 51c have three upper and lower nozzle arrays, and the nozzles 51a to 51c are each arranged with spray nozzles 52 arranged at predetermined pitch intervals.
In this modification, the upper and lower three-stage nozzle arrays 51a and 51b are configured to simultaneously perform the air blowing operation by the blowing nozzles 52 in each row as shown in FIG. 13A (simultaneous striking method). Alternatively, as shown in FIG. 13B, a mode (time difference impact method) in which the air blowing operation by the blowing nozzles 52 in each row is performed with a time difference may be used.
Further, as shown in FIG. 13 (c), the spray nozzles 52 in each row may be arranged in parallel, and a spraying operation by a parallel air flow (parallel hitting method) may be used, or FIG. 13 (d). As shown in FIG. 5, the spray nozzles 52 of each row may be arranged so as to be concentrated at one point at an angle, and a spraying operation by an air flow concentrated at one point (single point concentrated hitting method) may be employed.
As a matter of course, the air blowing device 50 may employ a nozzle array having four or more upper and lower stages.

Example 1
In this example, the performance of the ore sorting apparatus according to the first embodiment is evaluated.
In the present embodiment, as shown in FIG. 14A, a rock pulverized product G containing ore is fed out and dropped from the end of the belt conveyor 25 in the transport direction.
Here, the rock pulverized material G was selected to have a shape that is easy to roll.
14A, A is a position 0.5 m below the conveying surface of the rock crushed material G of the belt conveyor 25, and B is a position 0.5 m below the A position.
tf is the drop time from A to B (fall distance), x is the amount of protrusion from the tip of the belt conveyor 25 to B (when dropped by 1 m), and θ is the amount of rotation from A to B ( Per 100 ms), and the experiment was performed several times (N = 10 times).
In this example, the tension roll diameter of the belt conveyor 25 is 200 mm, and the conveying speed of the belt conveyor is 1 m / s.
In the first comparative example, the belt conveyor 25 is not used, and it is dropped directly from the vibration feeder 23. However, the vibration condition of the vibration feeder 23 is 60 Hz, and the conveyance speed is 8 m / min. It is.
The result of the comparison item about Example 1 and Comparative Example 1 is shown in FIG.
It is understood that Example 1 has less variation than Comparative Example 1 in all comparative items, and the falling behavior of the rock crushed material G is stable.

In Example 1, the experiment was performed 20 times at each conveyance speed under the condition that the conveyance speed of the belt conveyor 25 was changed, and the variation in the drop time, the variation in the pop-out amount, and the variation in the rotation amount were examined. The results shown in FIG. 17 were obtained.
However, the variation in drop time was 700 mm to 1200 mm. In addition, regarding the variation in the pop-out amount, the drop was set to 1200 mm. Furthermore, the variation in the rotation amount was between the heads of 700 mm to 1200 mm.
FIG. 15 shows the variation in drop time.
Here, the “bite-in amount 0” means that the rock crushed material is conveyed on the belt conveyor so as to draw a fall trajectory along the curvature of the peripheral surface of the curved portion of the conveying belt that is stretched over the stretch roll. It corresponds to the case where the speed is selected, and “no bite” means that the rock crushed material is conveyed on the belt conveyor so that it draws a curvature trajectory that is less than the curvature of the curved portion stretched over the stretch roll. Corresponding to the case where the speed is selected, “With bite” means that the conveyor speed of the belt conveyor is such that the rock crushed material is conveyed with a curvature locus larger than the curvature of the curved portion stretched over the stretch roll. Corresponds to the selected equivalent.
According to the figure, it is understood that the variation in fall time is smaller in the case of “no bite” than in the case of “bite in”, and in the case of “bite in”, the “bite amount” It is understood that the variation in the drop time increases as the speed decreases with respect to the speed corresponding to “0” (1.04 m / s in FIG. 15). This means that when the conveyor speed of the belt conveyor is extremely slow, the rock crushed material slides and moves at the contact area with the curved portion of the belt conveyor when the rock crushed material rolls out from the curved portion of the belt conveyor and falls. In connection with this, it is presumed that the fall start position and fall start posture from the belt conveyor vary.
Also, FIG. 16 shows the variation in the amount of rock pulverization, and FIG. 17 shows the variation in the amount of rotation of the crushed rock. In both cases, “bite amount” and “no bite amount” It is understood that there is less variation in the amount of rock crushed and the amount of rotation compared to the case of “with”, and when “with bite”, it is slower than the speed corresponding to “bite-in amount of 0”. It will be understood that the larger the deviation, the larger the variation in the pop-out amount and the rotation amount.
In Example 1, the tension roll diameter was changed from 200 mm to 300 mm, and the experiment was performed 20 times at each conveyance speed under the condition that the conveyance speed of the belt conveyor 25 was changed. When the variation in time, the variation in the pop-out amount, and the variation in the rotation amount were examined, a tendency similar to that in the case where the stretch roll was 200 mm was observed.

Moreover, when the fall locus | trajectory of the rock pulverized material in the part stretched over the stretch roll (belt roll diameter: 200 mm in this example) of a belt conveyor was investigated, changing the conveyance speed of a belt conveyor, the result shown in FIG. was gotten.
According to the figure, when the conveying speed of the belt conveyor is 1 m / s (speed substantially corresponding to “biting amount 0”), the fall trajectory of the rock crushed material substantially corresponds to the curvature of the curved portion of the belt conveyor. It is understood that the falling trajectory is stable. Also, when the conveyor speed of the belt conveyor is set to 1.2 m / s, for example, the falling trajectory of the rock crushed material becomes less than the curvature of the curved portion of the belt conveyor, but changes to a curvature locus close to the curvature of the curved portion of the belt conveyor. To be understood. Even in the case of “with bite”, if the bite amount is in the vicinity of 0 (for example, the conveyor speed of the belt conveyor is set to 0.8 m / s), the falling trajectory of the rock pulverized material will be the curvature of the curved part of the belt conveyor. It is understood that it becomes a close locus.
Furthermore, when the fall trajectory of the rock pulverized material in the portion stretched over the belt conveyor stretch roll (in this example, the stretch roll diameter: 300 mm) was examined by changing the conveyor speed of the belt conveyor, the results shown in FIG. was gotten.
According to the figure, when the conveyor speed of the belt conveyor is 1.2 m / s (speed substantially equivalent to “biting amount 0”), the falling trajectory of the rock crushed material substantially corresponds to the curvature of the curved portion of the belt conveyor. It is understood that the fall trajectory is stable. Also, if the conveyor speed of the belt conveyor is set to 1.4 m / s, for example, the fall trajectory of the rock crushed material is less than the curvature of the curved portion of the belt conveyor, but changes to a curvature locus close to the curvature of the curved portion of the belt conveyor. To be understood. Even in the case of “with bite”, if the bite amount is in the vicinity of 0 (for example, the conveyor speed of the belt conveyor is set to 1.0 m / s), the fall trajectory of the rock pulverized material is the curvature of the curved part of the belt conveyor. It is understood that it becomes a close locus.
Therefore, in the case of “no bite”, that is, if the speed condition exceeds the speed of the belt conveyor corresponding to “no bite”, the rock trajectory will be stable, but the belt conveyor speed should be set faster. If it is too much, the amount of movement of the rock pulverized material along the horizontal direction will increase. From the viewpoint of reducing the amount of movement of the rock pulverized material along the horizontal direction, the speed of the belt conveyor corresponding to “biting amount 0”. It is preferable to select a speed close to.
In addition, in the case of “with bite”, the fall trajectory of the rock crushed material is close to the curvature of the curved portion of the belt conveyor near “biting amount 0”, but depending on the shape of the rock crushed material, Since there is a possibility that variations in the fall time, pop-out amount, or rotation amount of objects may increase, at the time of selecting the conveyor speed of the belt conveyor, except for “with bite”, “no bite” or “no bite” It is preferable to select the vicinity of “bite-in amount 0” as an allowable range.

Example 2
Example 2 embodies the ore sorting apparatus according to the second embodiment, and evaluates the ore sorting performance by changing the air blowing conditions by the air blowing device 50.
In this example, ore sorting performance (flight distance j) was evaluated for the following four aspects.
(1) Single row spray nozzle Air pressure 0.7MPa
(2) Two-row spray nozzle Air pressure 0.7 MPa
Simultaneous blow method (3) Two-row spray nozzle Air pressure 1.0 MPa
Simultaneous impact method (4) Two-row spray nozzle Air pressure 1.0 MPa
Time difference impact method In addition, (1) performed the same experiment about the 1 row spray nozzle system for the comparison.

When each case was measured 10 times, the result shown in FIG. 20 was obtained.
It is understood that the distance (jumping amount) j from the partition wall of the sorting container is larger and the ore sorting performance is higher when the air blowing operation by the two-row nozzle method is performed than the one-row nozzle method. The
In the two-row spray nozzle system, it is understood that the flight distance j is larger when the air pressure is higher.
Further, it is understood that in the two-row spray nozzle method, the flight distance j is larger in the time difference impact method than in the simultaneous impact method.
In addition, in FIG. 20, Pz shows the falling position of the defective ore product on the conditions which do not implement the air spraying operation by the spray nozzle.

DESCRIPTION OF SYMBOLS 1 Rock ground material 1a Ore good 1b Ore defective 2 Supply device 3 Imaging tool 4 Discriminating device 5 Air blower 6 Belt-like carrier 7 Sorting container A Supply process B Imaging process C Discriminating process D Sorting process

Claims (9)

When selecting non-defective or defective ores determined in advance by the content ratio of the target mineral from the crushed rock,
A supply step of supplying the rock pulverized material so as to move along a predetermined movement trajectory;
An imaging step of imaging the rock crushed material supplied in the supply step in the middle of a movement trajectory,
After determining the area of the ore image part by separating the ore image part and the background part based on the imaging result of the imaging process, the ore is calculated by calculating the content ratio of the target mineral in the area of each ore image part Discriminating process for discriminating between non-defective and defective products,
One of the non-defective or defective products of the ore determined in the determining step is used as a spray target, and air is blown toward at least a majority region of the projection surface of the spray target toward the spray target. -A sorting process that sorts both by moving the movement trajectory of defective products,
Ore sorting method equipped with. An ore sorting device that sorts non-defective / defective products of ore predetermined by the content ratio of target minerals from crushed rocks,
A supply device for supplying the rock pulverized material so as to move the rock pulverized material along a predetermined movement trajectory;
An imaging instrument that images the rock crushed material supplied by the supply device in the middle of a movement trajectory,
After determining the area of the ore image part by separating the ore image part and the background part based on the imaging result by the imaging device, the ore is calculated by calculating the content ratio of the target mineral in the area of each ore image part Discriminating device for discriminating between non-defective and defective products,
Either one of the non-defective or defective products of the ore determined by the determination device is used as a spraying object, and the both ores are sorted by changing the movement trajectory of the non-defective or defective products. An air blowing device that blows air toward at least a majority region of the projection surface of the blowing object,
A mineral sorting device characterized by comprising: The mineral sorting apparatus according to claim 2,
The discrimination device is:
A first discriminating unit that discriminates an ore image part or a background part from an imaging result by the imaging instrument;
If the distance between the areas of adjacent ore image parts determined by the first determination part is within a predetermined set value, the areas of the adjacent ore image parts are combined as one ore, otherwise Then, the joint part to be unbonded as another ore,
Calculate the content ratio of the target mineral for each ore image area after processing by the joint, and determine whether the ore is non-defective or defective depending on whether the target mineral content ratio is equal to or greater than a predetermined threshold. An ore sorting device comprising: a second discriminating unit that performs the above operation. The ore sorting apparatus according to claim 2,
The discriminating device calculates density information from the imaging result of the imaging instrument, and ternizes the density information corresponding to the target mineral, the ore portion other than the target mineral, and the background portion, and other than the background portion of the ternary image Is determined as an ore image part, and the content ratio of the target mineral is calculated from the area occupied by the target mineral with respect to the ore image part of the ternary image. The ore sorting apparatus according to claim 2,
The ore sorting device is characterized in that the discrimination threshold is selected as a value that is less than 50% for a target mineral content ratio. The ore sorting apparatus according to claim 2,
The imaging instrument includes a first imaging instrument installed on the same side as the air blowing direction by the air blowing instrument, and a second imaging instrument capable of imaging from a direction different from the first imaging instrument. ,
The discriminating device discriminates the region of the ore image part based on the imaging result of the first imaging instrument, while referring to both imaging results of the first and second imaging instruments to the ore image part. An ore sorting device that calculates a content ratio of a target mineral contained therein. The ore sorting apparatus according to claim 2,
When the size of the rock pulverized material is within the range between the predetermined minimum dimension and the maximum dimension,
The air blowing device is characterized in that air can be individually blown and nozzles having a diameter smaller than the minimum dimension are arranged side by side so as to intersect the movement trajectory of the object to be sprayed at a pitch less than the minimum dimension. Ore sorter. The ore sorting apparatus according to claim 2,
The ore sorting apparatus according to claim 1, wherein the air blowing device blows air toward substantially the entire projection surface of the spray target. The ore sorting apparatus according to claim 2,
The air spraying apparatus includes nozzles that can be individually sprayed with air so as to intersect with the movement trajectory of the spraying object, and has a plurality of nozzle rows arranged in parallel. .