JP7523217B2 - Paper feeder - Google Patents

Description

The present invention relates to a paper feeder equipped with a sheet handling mechanism that uses air blowing.

Conventionally, in paper feeders capable of feeding large volumes of sheets to image forming devices such as copiers and printers, a technique for improving the sheet handling function by blowing air onto the sheets has been known. However, there has been a problem in that the optimal volume of air blown onto the sheets varies depending on the conditions at the time, even for the same sheet size, basis weight, and paper type, and it is very difficult to predict and set the optimal volume of air.

For this reason, Patent Literature 1 discloses a technology that acquires information representing the distance between the topmost sheet onto which air is blown and the next sheet in the stack as image data, calculates the distance between the sheets from the image data, and adjusts the air volume.

Furthermore, Patent Document 2 discloses a technology in which, in an air-blowing paper feeder, multiple optical sensors are arranged in the stacking direction of a sheet stack, and the air volume is controlled to an appropriate level by determining whether the difference in brightness at each location is equal to or less than a reference value.

JP 2010-254462 A JP 2014-047062 A

In Patent Document 1, the air volume is adjusted based on image data that indicates the distance between the top sheet and the next sheet, so the air volume adjustment cannot be made in time for the conveying operation, and as a result, the sheets still cannot be separated optimally one by one. In addition, there are problems with the image data processing taking time because the air volume is controlled by acquiring image data, and the need for expensive sensors to acquire image data, which increases the cost of the device.

Furthermore, when the stack of sheets is tightly packed together due to the influence of the usage environment, etc., it is difficult to accurately determine the degree of separation even if an image of the state of separation near the top sheet is captured and the data is analyzed. As a result, there is a problem in that it is not possible to adjust the air volume appropriately.

In Patent Document 2, the reflectance differs depending on the type of sheet, and the judgment threshold value needs to be set for each parameter, such as the type of sheet, size, and basis weight. Therefore, when determining the appropriate air volume, it is necessary to take these parameters into account in the evaluation, which poses the problem of requiring a lot of evaluation time and labor.

Furthermore, every time the type of sheet is changed, a judgment value corresponding to that sheet must be set, and the control program must be replaced, so it is expected that a significant amount of time and effort will be required before the actual machine can be put into operation.

The present invention aims to provide a paper feeder that is equipped with a control means that can accurately grasp the sheet stacking state, which changes depending on the type of sheet and the usage environment, and can appropriately set the optimal air volume to handle the sheets one by one according to the stacking state.

In order to solve the above problem, the sheet feeding device of the present invention comprises a stacking means for stacking a plurality of sheets in a predetermined stacking direction , an air blowing means for blowing air from a direction intersecting the stacking direction to eliminate adhesion between a plurality of sheets, including the topmost sheet which is located at the top of the plurality of sheets , a feeding means for sequentially feeding the topmost sheet being blown by the air blowing means from the stacking means, an emitting means for emitting light toward a plurality of sheets including the topmost sheet being blown by the air blowing means, and a detecting means for detecting the amount of reflected light of the light emitted by the emitting means reflected by the plurality of sheets including the topmost sheet being blown by the air blowing means for each of a plurality of regions along the stacking direction, and if the region in which the detecting means detects the maximum amount of reflected light is located at the top among the plurality of regions along the stacking direction, the air volume of the air blowing means is reduced, and if the region in which the detecting means detects the maximum amount of reflected light is located lower in the stacking direction than the region in which the detecting means detects the minimum amount of reflected light among the plurality of regions, the air volume of the air blowing means is increased.

The paper feeder of the present invention monitors the amount of light reflection at multiple points along the stacking direction of the stacked sheet bundle, making it possible to grasp the sheet stacking state, which changes depending on the type of sheet and the usage environment. In addition, the ratio of the minimum and maximum light reflection amount to the total amount of light reflection at each point at that time is calculated, and the air volume is adjusted by the blowing means based on this calculated result, allowing optimal sheet handling.

1 is a cross-sectional view of an image forming processing system including a paper feeding device according to the present invention. FIG. 2 is a cross-sectional view showing the main internal configuration of the paper feed device. FIG. 2 is a block diagram of a paper feed device. FIG. 2 is a schematic diagram of a detection unit according to the first embodiment. 11 is a calculation table based on a first determination example of the first embodiment. 13 is a calculation table based on a second determination example of the first embodiment. 13 is a calculation table based on a third determination example of the first embodiment. FIG. 4 is a flow diagram of control in the first embodiment. FIG. 11 is a schematic diagram of a detection unit according to a second embodiment. FIG. 11 is a connection circuit diagram of a detection unit and a calculation unit according to the second embodiment. 13 is a calculation table based on a first determination example of the second embodiment. 13 is a calculation table based on a second determination example of the second embodiment. 13 is a calculation table based on a third determination example of the second embodiment. FIG. 11 is a flow diagram of control in the second embodiment.

The following is a detailed description of an embodiment of the paper feeder according to the present invention. FIG. 1 shows an example of the configuration of an image forming processing system 10 that can handle large amounts of sheets. This image forming processing system 10 is configured by combining an image forming device 11 with a paper feeder 12 according to the present invention. The image forming device 11 is equipped with a reading means 16 consisting of a platen glass 14 and an ADF 15, an image forming means 17, and a conveying means 19 that feeds and conveys sheets from an internal cassette 18. The paper feeder 12 is for continuously supplying a large amount of sheets from the outside to the image forming device 11. This paper feeder 12 is equipped with a lift tray 21 that can be raised and lowered while a large amount of sheets P is loaded, and continuous image formation processing is performed by connecting a paper feed path 22 from this lift tray 21 to the conveying means 19 of the image forming device 11.

As shown in FIG. 2, the sheet feeder 12 includes a lift tray 21 that can be raised and lowered, a feed roller 31 that contacts the top sheet P of the sheet stack stacked on the lift tray 21, a separation roller pair 32 provided upstream of the sheet feed path 22 toward the image forming device 11, and a transport roller pair 34 provided downstream of the sheet feed path 22. The lift tray 21 is provided with a side regulating plate 23 that regulates the side of the stacked sheet stack, and a rear end regulating plate 24 that regulates the rear end of the sheet stack, which can be slid. In addition, a detection unit 35 for detecting the stacking state of the sheets is provided between the feed roller 31 and the separation roller pair 32.

When the sheet feeder 12 having the above configuration is started, the top surface of the sheet on the lift tray 21 is raised by the pay-out roller 31 to a pay-out position where it can be paid out, the pay-out roller 31 pays out the sheet, the separation roller pair 32 separates the sheets one by one, and the conveyance roller pair 34 conveys them toward the image forming device 11. The lift tray 21 is controlled so that the top surface of the sheet rises to the pay-out position each time the pay-out roller 31 pays out a predetermined number of sheets.

The lift tray 21 is provided with an air blowing means (air blowing unit) 40 for eliminating adhesion between stacked sheets. The air blowing unit 40 has a fan 41 that blows air from the outside into a duct (not shown) for blowing air. In some cases, a heater is provided in the duct, and air heated by the heater is blown in by the fan 41. The duct extends toward an air outlet 45, and is configured so that the air blown in by the fan 41 hits the top surface of the sheet stack. As will be described later, the sheet feeder 12 is provided with a control means for realizing appropriate sheet handling so as to prevent double feeding, etc., by adjusting the rotation of the fan 41 according to the sheet stacking state detected by the detection unit 35.

Figure 3 is a block diagram showing the configuration of the paper feeder 12. The control unit 36 includes a calculation unit 37 and a determination unit 38 that perform air volume control, and a control board that includes a CPU, a ROM, a RAM, an interface that connects to external devices and transmits and receives signals, and inputs instructions from the user input through the operation unit 13 shown in Figure 1 via the image forming device 11, and issues instructions to each processing unit. When a job such as printing is input from the operation unit 13, the lift tray 21 is driven to raise the top sheet stacked on the lift tray 21 until it reaches the feed roller 31. Next, the feed roller 31 and the separation roller pair 32 are driven to pick up the top sheet from the stack and feed it to the separation roller pair 32, which then separates the fed sheets one by one and transports them to the paper feed path 22. When performing such sheet feeding, separation, and transport operations, the amount of air blown by the fan 41 is adjusted based on the separation state of the sheets detected by the detection unit 35.

Figure 4 shows the configuration of the detection unit 35 in the first embodiment in response to the stacking state of the sheets. The detection unit 35 in this embodiment has a plurality of reflective optical sensors consisting of a light emitting unit and a light receiving unit arranged along the stacking direction of the sheets. In this embodiment, three optical sensors are used, but at least two or more are sufficient, and the more the number of sensors arranged, the more accurate the stacking state of the sheets can be detected. The upper optical sensor 35a of the three optical sensors is arranged so that it can detect reflected light from the upper layer area where the sheets in the upper layer of the stacked sheet bundle can be blown up by the fan 41, and the lower optical sensor 35c is arranged so that it can detect reflected light from the lower layer area of the sheet bundle. It is preferable that the three optical sensors are arranged at equal intervals, and the remaining optical sensor 35b is arranged approximately in the middle layer of the optical sensors 35a and 35c. In the following description, the maximum light reflection amount is indicated as (Vmax) and the minimum light reflection amount is indicated as (Vmin). In addition, the judgment standard value for determining whether the amount of air required for sheet handling (separation) is insufficient or excessive is set appropriately depending on the thickness and size of the sheet, but in the following embodiments, the judgment standard value will be described as 15%.

Figure 4(a) is a schematic diagram showing a state in which the stacked sheets P are being sorted by an appropriate air volume (sheets are located in the blowing area at appropriate intervals). In this way, if the sheets are being sorted appropriately, as shown in Figure 5, the light reflection amounts of the optical sensors 35a to 35c corresponding to the detection positions R1 to R3 will be approximately the same. The calculation unit 37 calculates the sum of the output voltage values of the optical sensors 35a to 35c corresponding to the light reflection amounts, and obtains the ratio of the output voltage value of each optical sensor 35a to 35c to this sum of the output voltage values. The highest ratio among them is set as Vmax, and the lowest ratio is set as Vmin. The difference between the ratios (Vmax-Vmin) is then used as the judgment target value, and the air volume in the blowing unit 40 is set by comparing it with the judgment reference value. Figure 5(a) is an example of an ideally sorted state, and the judgment target value is 0 because all of the optical sensors 35a to 35c are about 33%. Also, as shown in Figures 5(b) and (c), although there is variation in the output voltage values of the optical sensors 35a to 35c, if the sheets are handled relatively uniformly without any problems, the judgment target value will be smaller than the judgment reference value, and the judgment unit 38 will determine that the sheets have been handled properly.

Figure 4(b) is a schematic diagram showing a state in which the stacked sheets P accumulate at the top due to excessive airflow. In such a state of excessive airflow, as shown in Figure 6, the difference in the light reflection amount of the optical sensors 35a to 35c corresponding to the detection positions R1 to R3 becomes large, so the judgment target value calculated by the calculation unit 37 becomes larger than the judgment reference value. Since the sheets accumulate at the top of the blowing up area, the sensor with Vmax is located higher in the sheet stacking direction X than the sensor with Vmin. In other words, when the judgment target value is larger than the judgment reference value and the optical sensor 35a with Vmax is located higher in the sheet stacking direction X than the optical sensor 35c with Vmin, it is judged by the judgment unit 38 that the airflow is excessive. As shown in Figures 6(a) to (c), in the case of excessive airflow, one of the optical sensors 35a and 35b is Vmax, and one of the optical sensors 35b and 35c is Vmin.

Figure 4(c) is a schematic diagram showing a state in which the stacked sheets P are not blown up due to insufficient airflow. In such a state of insufficient airflow, as shown in Figure 7, the light reflection amount of the optical sensors 35a to 35c corresponding to the detection positions R1 to R3 becomes large as in the case of excessive airflow, so the judgment target value calculated by the calculation unit 37 becomes larger than the judgment reference value. Since the sheets accumulate in the lower part of the blowing up area, the sensor with Vmax is located lower in the sheet stacking direction X than the sensor with Vmin. In other words, when the judgment target value is larger than the judgment reference value and the sensor with Vmax is located lower in the sheet stacking direction X than the sensor with Vmin, it is judged that there is insufficient airflow. As shown in Figures 7(a) to (c), in the case of insufficient airflow, one of the optical sensors 35b and 35c becomes Vmax, and one of the optical sensors 35a and 35b becomes Vmin.

Figure 8 shows the first control flow according to the above configuration. First, when a sheet feeding operation is started by an instruction to execute a job such as printing, the sheet feeding device 12 drives the fan 41 at the initial setting air volume corresponding to the sheet type set by the user and starts blowing air onto the side of the stack of sheets (ST11). Next, while the air is being blown, the reflected light corresponding to R1 to R3 on the side of the stack of sheets is detected by the optical sensors 35a to 35c, and the output voltage value is obtained (ST12). Then, the ratio of the minimum and maximum light reflection amounts to the sum of the output voltage values of the optical sensors 35a to 35c is calculated, and the result (value to be judged) is compared with a predetermined judgment reference value (15% as an example) (ST13). If the comparison result indicates that the judgment target value is equal to or less than the predetermined judgment reference value, it is judged to be the appropriate air volume (ST14), and the set air volume at that time is saved, and the driving of the fan 41 is stopped (ST15), and the control is terminated. When this control is completed, the topmost sheet in the stack is picked up using the feed roller 31 and feeding begins.

On the other hand, if the comparison in (ST13) finds that the judgment target value is greater than the judgment reference value, the process proceeds to (ST16). In this (ST16), if the position of the sensor where the light reflection amount of the optical sensors 35a to 35c is Vmax is higher in the sheet stacking direction X than the position of the sensor where the light reflection amount is Vmin, it is judged that the air volume is excessive, and a process to reduce the air volume of the fan 41 is performed (ST17). After the air volume is reduced, the process returns to (ST12) again, and this flow is repeated until it is judged that the air volume is appropriate.

In the process of (ST16) above, if the position of the sensor where the light reflection amount of the optical sensors 35a to 35c is Vmax is lower in the sheet stacking direction X than the position of the sensor where the light reflection amount is Vmin, it is determined that the air volume is insufficient, and a process is performed to increase the air volume of the fan 41 (ST18). After the air volume has been increased, the process returns to (ST12) again, and this flow is repeated until it is determined that the air volume is appropriate.

Next, the control means of the second embodiment will be described with reference to Figures 9 to 14. Note that since the overall control configuration is similar to that of the first embodiment shown in Figure 3, the configuration of the detection unit 35 and its control in this embodiment will be described with reference to Figure 3.

Figure 9 shows the configuration of the detection unit 35 of this embodiment. It is composed of a light emitting unit 51 such as a light emitting element or LED that illuminates a predetermined range on the side of the stacked sheet bundle, a condensing lens 52 that condenses the reflected light, and an optical position sensor 53 that receives the condensed light and detects the incident position of the light and the amount of light reflection. When the reflected light through the condensing lens 52 is incident on the optical position sensor 53, an electric charge proportional to the amount of light reflection is generated at the incident position. This electric charge reaches the resistive layer as a photocurrent, is divided in inverse proportion to the distance to each electrode, and is taken out from the output electrode. It is desirable to arrange this optical position sensor so that it condenses and guides the reflected light to an area where the top sheet of the stacked sheet bundle can be blown up by the fan 41.

10 shows an example of a connection circuit between the optical position sensor 53 and the calculation unit 37 in the detection unit 35. The currents IL1 and IL2 output from the optical position sensor 53 are input to the calculation unit 37 through an amplifier 54, where a predetermined calculation is performed to calculate the determination target value (Vout). The calculation conditions and calculation formulas in this embodiment are shown below.
<Conditions>
Vcc=5V
IL1+IL2=IC
<Calculation formula>
IL=(IL1-IL2)/(IL1+IL2)
Vout=0.5Vcc×IL+0.5Vcc

Figure 9(a) is a schematic diagram showing a state in which the stacked sheets P are being handled by the appropriate amount of air (the sheets are positioned in the blowing area at appropriate intervals). In this way, if the sheets are being handled properly, the light position sensor 53 will have the same amount of light reflection at all incident positions, as shown in Figure 11. If the range of the judgment reference value Vout0 here is (2.2 [V] < Vout0 < 2.8 [V]), the judgment target value (Vout) calculated based on the currents IL1 and IL2 output from the light position sensor 53 will be within the judgment reference value. As a result, the judgment unit 38 judges that the sheets have been handled properly.

Figure 9 (b) is a schematic diagram showing a state in which excess airflow causes stacked sheets P to accumulate at the top. In such an excess airflow state, as shown in Figure 12, the amount of light reflected by the optical position sensor 53 varies greatly depending on the incident position. If the range of the judgment reference value Vout0 here is (Vout≦2.2 [V]), then the judgment target value (Vout) calculated based on the currents IL1 and IL2 output from the optical position sensor 53 falls outside the judgment reference value. As a result, the judgment unit 38 judges that the airflow is excessive.

Figure 9 (c) is a schematic diagram showing a state in which the stacked sheets P are not blown up to the upper layer due to insufficient airflow. In such a state of insufficient airflow, as shown in Figure 13, the difference in the amount of light reflected by the optical position sensor 53 increases depending on the incident position, just as in the case of excessive airflow. If the range of the judgment reference value Vout0 here is (2.8 [V] ≦ Vout), the judgment target value calculated based on the currents IL1 and IL2 output from the optical position sensor 53 falls outside the judgment reference value. As a result, the judgment unit 38 judges that there is insufficient airflow.

Figure 14 shows the second control flow according to the above configuration. First, when a sheet feeding operation is started by an instruction to execute a job such as printing, the sheet feeding device 12 drives the fan 41 at the initial setting air volume according to the sheet type set by the user, and starts blowing air onto the side of the stack of stacked sheets (ST21). Next, while air is being blown, the light reflected from the side of the sheets is detected by the optical position sensor 53, and a calculation is performed by the calculation unit 37, and the calculation result is obtained as the judgment target value of the optical position sensor (ST22).

In (ST23), the judgment value Vout calculated in (ST22) is compared with a predetermined judgment reference value range (for example, 2.2 [V] < Vout < 2.8 [V]).

If the comparison result indicates that the value is within the range of the predetermined judgment criteria, the process proceeds to (ST24), and the set air volume at that time is saved, and then the drive of the fan 41 is stopped (ST25) and control ends. When this control ends, the topmost sheet in the stack is picked up by the feed roller 31 and feeding begins.

On the other hand, if the comparison process in (ST23) finds that the judgment target value is outside the range of the predetermined judgment reference value, proceed to (ST26). In this (ST26), if the judgment target value of the optical position sensor 53 is smaller than the judgment reference value, it is determined that the air volume is excessive, and control is performed to reduce the air volume of the fan 41 (ST27). After the air volume is reduced, the process returns to (ST22) again, and this flow is repeated until it is determined that the air volume is appropriate.

In the above process (ST26), if the judgment target value of the optical position sensor 53 is greater than the judgment reference value, it is judged that the air volume is insufficient, and control is performed to increase the air volume of the fan 41 (ST28). After the air volume has increased, the process returns to (ST22) again, and this flow is repeated until it is judged that the air volume is appropriate.

The first and second controls can be implemented by program processing in the control unit 36, or by hardware such as an external circuit.

REFERENCE SIGNS LIST 10 Image forming processing system 11 Image forming device 12 Paper feed device 13 Operation unit 14 Platen glass 15 ADF
REFERENCE SIGNS LIST 16 Reading means 17 Image forming means 18 Built-in cassette 19 Conveying means 21 Lifting tray 22 Paper feed path 23 Side regulating plate 24 Rear end regulating plate 31 Feed roller 32 Separation roller pair 34 Conveying roller pair 35 Detecting section 35a, 35b, 35c Optical sensor 36 Control section (controlling means)
37 Calculation section 38 Determination section 40 Blowing unit (blowing means)
41 Fan 45 Air outlet 51 Light emitter 52 Condenser lens 53 Optical position sensor 54 Amplifier

Claims (9)

A stacking means for stacking a plurality of sheets in a predetermined stacking direction ;
a blowing unit that blows air from a direction intersecting the stacking direction to eliminate adhesion between a plurality of sheets including a top sheet located at the top of the plurality of sheets ;
a feeding means for sequentially feeding the topmost sheet, which is being blown by the blowing means, from the stacking means;
a light emitting means for emitting light toward a plurality of sheets including the top sheet being blown by the blowing means;
a detection unit that detects an amount of light reflected by a plurality of sheets including the top sheet being blown by the blowing unit, for each of a plurality of regions along the stacking direction, the amount of light being reflected by the light emitting unit being light emitted by the light emitting unit,
When the area in which the detection means detects the maximum reflected light amount is located at the top among the multiple areas along the loading direction, the air volume of the air blowing means is reduced,
A sheet feeding device that increases the air volume of the air blowing means when the area in which the maximum reflected light amount is detected is lower in the stacking direction than the area among the multiple areas in which the detection means detects the minimum reflected light amount . The blowing means blows air at a preset initial air volume,
When the area in which the detection means detects the maximum reflected light amount is located at the top among the multiple areas along the stacking direction, the air volume of the air blowing means is reduced from the initial set air volume,
2. A sheet feeding device as described in claim 1, wherein when the area in which the maximum reflected light amount is detected is lower in the stacking direction than the area among the multiple areas in which the detection means detects the minimum reflected light amount, the air volume of the blowing means is increased from the initially set air volume . A stacking means for stacking a plurality of sheets in a predetermined stacking direction;
a blowing unit that blows air from a direction intersecting the stacking direction to eliminate adhesion between a plurality of sheets including a top sheet located at the top of the plurality of sheets;
a feeding means for sequentially feeding the topmost sheet, which is being blown by the blowing means, from the stacking means;
a light emitting means for emitting light toward a plurality of sheets including the top sheet being blown by the blowing means;
a detection unit that detects an amount of light reflected by a plurality of sheets including the top sheet being blown by the blowing unit, for each of a plurality of regions along the stacking direction, the amount of light being reflected by the light emitting unit being light emitted by the light emitting unit,
maintain the air volume of the blower when a determination value, which is the difference between a maximum reflected light amount that is the maximum among the reflected light amounts for each of the plurality of regions detected by the detection means and a minimum reflected light amount that is the minimum among the reflected light amounts for each of the plurality of regions detected by the detection means, is equal to or smaller than a predetermined determination reference value;
When the judgment target value is greater than the predetermined judgment reference value and the area in which the maximum reflected light amount is detected is located at the top of a plurality of areas along the stacking direction, the air volume of the air blowing means is reduced,
A sheet feeding device that increases the air volume of the blowing means when the judgment target value is greater than the specified judgment reference value and when the area in which the maximum reflected light amount is detected is lower in the stacking direction than the area in which the detection means detects the minimum reflected light amount . The blowing means blows air at a preset initial air volume,
maintain the initially set air volume of the blower when a determination target value, which is a difference between a maximum reflected light amount that is the maximum among the reflected light amounts for each of the plurality of regions detected by the detection means and a minimum reflected light amount that is the minimum among the reflected light amounts for each of the plurality of regions detected by the detection means, is equal to or smaller than a predetermined determination reference value;
When the judgment target value is greater than the predetermined judgment reference value and when the area in which the maximum reflected light amount is detected is located at the top of a plurality of areas along the stacking direction, the air volume of the blowing means is reduced from the initial set air volume,
A sheet feeding device as described in claim 3, wherein when the judgment target value is greater than the specified judgment reference value and when the area in which the maximum reflected light amount is detected is lower in the stacking direction than the area in which the detection means detects the minimum reflected light amount, the air volume of the blowing means is increased from the initial setting air volume. 5. An image forming processing system comprising: the sheet feeding device according to claim 1; and an image forming device for forming an image on the sheet fed from the sheet feeding device. A stacking means for stacking a plurality of sheets in a predetermined stacking direction;
a blowing unit that blows air from a direction intersecting the stacking direction to eliminate adhesion between a plurality of sheets including a top sheet located at the top of the plurality of sheets;
a feeding means for sequentially feeding the topmost sheet, which is being blown by the blowing means, from the stacking means;
a light emitting means for emitting light toward a plurality of sheets including the top sheet being blown by the blowing means;
a detection means for detecting an amount of light reflected by a plurality of sheets including the top sheet being blown by the blowing means, the amount of light being reflected by the light emitting means for each of a plurality of regions along the stacking direction;
When the area in which the detection means detects the maximum reflected light amount is located at the top among the multiple areas along the loading direction, the air volume of the air blowing means is reduced,
a control means for controlling the blowing means to increase an air volume of the blowing means when the area in which the maximum reflected light amount is detected is located lower in the loading direction than the area in which the detection means detects the minimum reflected light amount among the plurality of areas;
and an image forming means for forming an image on the sheet fed from the feeding means. The blowing means blows air at a preset initial air volume,
When the area in which the detection means detects the maximum reflected light amount is located at the top among the multiple areas along the loading direction, the air volume of the air blowing means is reduced,
7. An image forming apparatus as described in claim 6, wherein when the area in which the maximum reflected light amount is detected is lower in the stacking direction than the area among the plurality of areas in which the detection means detects the minimum reflected light amount, the air volume of the blowing means is increased from the initially set air volume. A stacking means for stacking a plurality of sheets in a predetermined stacking direction;
a blowing unit that blows air from a direction intersecting the stacking direction to eliminate adhesion between a plurality of sheets including a top sheet located at the top of the plurality of sheets;
a feeding means for sequentially feeding the topmost sheet, which is being blown by the blowing means, from the stacking means;
a light emitting means for emitting light toward a plurality of sheets including the top sheet being blown by the blowing means;
a detection means for detecting an amount of light reflected by a plurality of sheets including the top sheet being blown by the blowing means, the amount of light being reflected by the light emitting means for each of a plurality of regions along the stacking direction;
maintain the air volume of the blower when a determination value, which is the difference between a maximum reflected light amount that is the maximum among the reflected light amounts for each of the plurality of regions detected by the detection means and a minimum reflected light amount that is the minimum among the reflected light amounts for each of the plurality of regions detected by the detection means, is equal to or smaller than a predetermined determination reference value;
When the judgment target value is greater than the predetermined judgment reference value and the area in which the maximum reflected light amount is detected is located at the top of a plurality of areas along the stacking direction, the air volume of the air blowing means is reduced,
An image forming apparatus comprising: a control means for controlling the air blowing means to increase the air volume of the air blowing means when the judgment target value is greater than the specified judgment reference value and when the area in which the maximum reflected light amount is detected is lower in the loading direction than the area in which the detection means detected the minimum reflected light amount; and an image forming means for forming an image on a sheet fed from the feeding means. The blowing means blows air at a preset initial air volume,
When the judgment target value is equal to or less than the predetermined judgment reference value, the air volume of the blowing means is maintained;
When the judgment target value is greater than the predetermined judgment reference value and when the area in which the maximum reflected light amount is detected is located at the top of a plurality of areas along the stacking direction, the air volume of the blowing means is reduced from the initial set air volume,
9. An image forming apparatus as described in claim 8, wherein when the judgment target value is greater than the specified judgment reference value and when the area in which the maximum reflected light amount is detected is lower in the stacking direction than the area in which the detection means detects the minimum reflected light amount, the image forming apparatus controls the blowing means to increase the air volume of the blowing means from the initially set air volume.

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