JP6774644B2 - Sheet feeding device and image forming device - Google Patents

Description

The present invention relates to a sheet feeding device and an image forming device.

Conventionally, as a sheet feeding device of an image forming apparatus, air is blown onto the upper sheet of a bundle of sheets loaded on the sheet loading portion of the sheet feeding device to raise the sheet, and at least the top sheet is separated from the second sheet. Later, it is known that the top sheet is fed by a conveying means.

Patent Document 1 includes, as the sheet feeding device, a blowing means for blowing air from a spray port provided on a side fence to a sheet bundle, and sets the air blowing time for blowing air from the spray port to the sheet bundle. The ones that become longer as the size increases are described.

However, when an expansion cartridge that enables loading of long sheets is attached and a bundle of long sheets made of long sheets is loaded, there is a risk that paper feeding defects such as double feeding and non-feeding may occur.

In order to solve the above problems, the present invention includes a sheet loading unit for loading a sheet bundle, a conveying means for conveying the top sheet of the sheet bundle, and an air blowing means for blowing air on the sheet bundle. In a sheet feeding device to which an expansion cartridge capable of mounting a long sheet by expanding the length of the sheet loading section in the sheet transporting direction can be attached, the air blowing means loads the sheet from at least the downstream side in the sheet transporting direction. Air is blown to the upper sheet of the sheet bundle loaded on the unit, and for at least two types of sheet bundles having different lengths in the sheet transport direction, the wind force of air for the sheet bundle having the longer sheet transport direction length. The control means is provided with a control means for controlling the air blowing means so that the energy is larger than the wind energy of the air for the sheet bundle having the shorter sheet transport direction length, and the control means adjusts the air blowing time. It is characterized by adjusting the wind energy .

According to the present invention, it is possible to suppress double feeding or non-feeding when an expansion cartridge is attached and a long sheet is mounted.

The schematic block diagram of the image formation system of this embodiment. The schematic block diagram of the image forming apparatus of this embodiment. The schematic block diagram of the paper feed device of this embodiment. Schematic perspective view of the vicinity of the paper feed tray of the paper feed device. Perspective view of the front blower. The perspective view which shows the internal structure of the front blower. The block diagram which shows an example of the main part structure of the control system in this image forming apparatus. The figure explaining the paper feed operation. (A) is a perspective view showing a paper feed device to which an expansion cartridge is not attached, and (b) is a perspective view showing a paper feed device to which an expansion cartridge is attached. (A) is a perspective view showing a paper feed tray and an expansion cartridge, and (b) is a view showing a state in which the opening / closing cover of the expansion cartridge is opened. The figure explaining the installation of the extension loading platform. The figure explaining the set of papers when the expansion cartridge is attached. The control flow diagram of the air blowing setting of this embodiment.

Hereinafter, an embodiment of a paper feeding device to which the present invention is applied will be described.
FIG. 1 is a schematic configuration diagram of the image forming system 1 of the present embodiment.
As shown in FIG. 1, the image forming system 1 includes an image forming apparatus 100 as an image forming means for forming an image on paper, and a paper feeding device 200 for feeding paper to the image forming apparatus. The paper feeding device 200 is provided on the side surface of the image forming device 100 main body.

First, the overall configuration and operation of a printer to which the paper feeding device of the present embodiment can be applied and an image forming device such as a copying machine having an equivalent image forming function will be described.
FIG. 2 is a schematic configuration diagram of the image forming apparatus 100 according to the present embodiment.
The image forming apparatus 100 is a full-color printer using four color toners of yellow (Y), cyan (C), magenta (M), and black (K), and a full-color copying machine having an equivalent image-forming function. As shown in FIG. 2, four image forming units 101Y, 101M, 101C, and 101K that image with each color toner are arranged side by side in the upper part of the main body of the apparatus. Since the configurations and operations of the image-forming units 101Y, 101M, 101C, and 101K are substantially the same, the image-forming units will be described here by omitting the color symbols (Y, M, C, K). .. In the image forming unit 101, a charger 103, a developing device 104, a cleaning device 105, and the like are arranged around the photoconductor drum 102 as an image carrier. Further, the exposure means 107 is arranged above the photoconductor drum 102.

Below the four image forming units 101Y, 101M, 101C, and 101K, intermediate transfer belts 108 hung around a plurality of support rollers are arranged. The intermediate transfer belt 108 is driven to travel in the direction of arrow A by rotationally driving one of the support rollers by a driving means. A transfer roller 106 as a primary transfer means is arranged so as to face the photoconductor drum 102 of each image forming unit with the intermediate transfer belt 108 interposed therebetween.

In each image forming unit 101, the photoconductor drum 102 is rotationally driven counterclockwise in the drawing, and the photoconductor surface is uniformly charged to a predetermined polarity by the charger 103. Next, the charged surface is irradiated with a light-modulated laser beam emitted from the exposure means 107, whereby an electrostatic latent image is formed on the photoconductor drum 102. The electrostatic latent image is developed by the toner applied from the developing device 104 and visualized as a toner image. The yellow, cyan, magenta, and black toner images formed by each image forming unit are sequentially superimposed and transferred on the intermediate transfer belt 108.

On the other hand, a paper feeding unit 114 having the paper feeding trays 114a and 114b is provided at the lower part of the apparatus main body, and the paper feeding unit 114 or the paper feeding device 200 described later attached to the image forming device 100 For example, transfer paper is supplied as a recording medium. The fed transfer paper is conveyed toward the resist roller 111 as shown by arrow B.

The transfer paper that has been abutted against the resist roller 111 and temporarily stopped is sent out from the resist roller 111 at the timing of the toner image on the intermediate transfer belt 108, and the secondary transfer roller 109 and the intermediate transfer belt 108 come into contact with each other. It is sent to the secondary transfer section. A voltage opposite to the charging polarity of the toner is applied to the secondary transfer roller 109, whereby the layered toner image (full-color image) on the intermediate transfer belt 108 is transferred onto the transfer paper. The transfer paper after the toner image transfer is conveyed to the fixing device 113 by the transfer belt 112, and the toner is fixed to the transfer paper by heat and pressure in the fixing device 113. The transfer paper after the toner image is fixed is discharged to the outside of the machine as shown by an arrow C, and is discharged onto the paper ejection tray.

In the case of single-sided printing on the back side (face-down paper ejection), the front and back sides of the paper are reversed by ejecting the paper to the outside of the machine as shown by an arrow C through the paper reversing portion 115. Further, in the case of double-sided printing, the fixed paper is re-fed from the re-feeding path 117 to the resist roller 111 via the double-sided reversing section 116, and the toner image is transferred from the intermediate transfer belt 108 to the back surface of the paper. The paper after the toner image transfer is fixed by the fixing device 113, and as shown by the arrow C from the fixing device 113 as in the case of single-sided printing, or as indicated by the arrow C via the paper reversing portion 115, the paper is removed from the machine. It is ejected and is ejected on the output tray. Switching claws 118 and 119 for switching the paper transport direction are appropriately arranged.

In the case of monochrome printing, in the image forming apparatus 100 of this example, a toner image is imaged using only the black (K) image forming unit 101K, and the toner image is transferred onto the transfer paper via the intermediate transfer belt 108. To do. The handling of the paper after fixing the toner image is the same as in the case of full-color printing.

A toner bottle setting unit 120 for setting each color toner bottle 121 containing toner to be supplied to the developing device 104 of each image forming unit is provided on the upper surface of the apparatus main body. Further, an operation unit 124 having a display unit 122 and an operation panel 123 is also provided on the upper surface of the apparatus main body. Further, a paper loading unit D from a paper feeding device (see FIG. 3), which will be described later, is provided on the right side surface in the drawing of the device main body. The paper loading section D is provided with an opening 125 for receiving the paper and a transporting means 126 for transporting the paper.

FIG. 3 is a schematic explanatory view of the paper feeding device 200 of the present embodiment provided on the side surface of the device main body.
The paper feed device 200 includes two upper and lower paper feed trays 10. Each paper tray 10 includes a paper loading platform 11 which is a paper loading unit for loading a bundle of paper P. In the present embodiment, each paper feed tray 10 can store up to about 2500 sheets of paper. Above each paper feed tray 10, a paper feed unit 20 is arranged as a transport means for sucking and transporting the top-level paper of the paper bundle loaded on the paper feed tray 10. The paper feed unit 20 includes a suction belt 21 and a suction device 23, which are transport members.

The paper loaded on the lower paper feed tray 10 is conveyed to the image forming apparatus 100 main body by the outlet roller pair 80 through the lower transfer path 82. The paper loaded on the upper paper feed tray 10 is conveyed to the image forming apparatus 100 main body by the outlet roller pair 80 through the upper transfer 81.

FIG. 4 is a schematic perspective view of the vicinity of the paper feed tray 10. In FIG. 4, the paper feed unit 20 is marked by shifting it in the direction of the arrow in the drawing from the original arrangement location for easy understanding.
The suction belt 21 of the paper feed unit 20 is stretched by two tension rollers 22a and 22b, and suction holes penetrating from the front surface side to the back surface side of the belt are provided in the entire circumferential direction. Further, a suction device 23 is provided inside the suction belt 21. The suction device 23 is connected to a suction fan that sucks air through an air duct that is an air flow path, and the suction device 23 generates a negative pressure downward to suck the paper P on the lower surface of the suction belt 21. It acts to make you.

Further, the paper feed tray 10 is provided with a blower device 17 which is an air blowing means for blowing air onto the paper above the paper bundle P. The blower 17 has a front blower 12 and a side blower 14.

The side blower 14 is provided on the pair of side fences 13 and blows air to the upper side surface of the paper bundle P in the direction indicated by the arrow b in the drawing. The side blower 14 is provided with a side levitation nozzle that handles the paper bundle P and guides air in the direction of levitation, and has a side blower 14a that sends air to this nozzle. The air blown from the side levitation nozzle in the direction indicated by the arrow b in the figure is called side air. This side air is discharged from the discharge port 13a provided at a position facing the upper part of the paper bundle P of each side fence 13, and is sprayed on the side surface of the upper part of the paper bundle P. The air blown from the front blower 12 and the discharge ports of the pair of side fences 13 raises the paper on the upper part of the paper bundle.

Further, the paper feed tray 10 is provided with an end fence 25 for aligning the rear ends of the paper bundles P loaded on the paper loading platform 11. The paper loading platform 11 is configured to be able to move up and down in the direction of arrow A in the drawing by the lifting device 19.

FIG. 5 is a perspective view of the front blower device 12, and FIG. 6 is a perspective view showing the internal configuration of the front blower device 12.
The front blower device 12 blows air to the upper tip (downstream end in the paper feeding direction) of the paper bundle P. The front blower 12 includes a levitation nozzle 15a that guides air in the direction of levitation of the paper bundle P, a separation nozzle 16a that guides and separates air between the uppermost levitation paper and the second levitation paper, and levitation. A floating blower 15 that sends air to the nozzle 15a and a separation blower 16 that sends air to the separation nozzle 16a are arranged. Further, an air chamber 130 having a floating air chamber portion 130a and a separation air chamber portion 130b (see FIG. 6) is provided.

Of the nozzles, the air blown from the levitation nozzle 15a is called levitation air, and the air blown from the separation nozzle 16a is called separation air. The levitation air is blown out in the direction of arrow a1 in FIG. 4 from a portion facing the upper end of the paper bundle P (downstream end in the paper feed direction), and the upper end of the paper bundle P (downstream end in the paper feed direction). Is sprayed on. The separated air is blown out in the direction of arrow a2 in FIG. 4 from a position facing the upper end of the paper bundle P (the end on the downstream side in the paper feeding direction), and the uppermost paper adsorbed on the suction belt 21 and the second paper floating up. It is sprayed between.

Further, as shown in FIG. 6, a levitation shutter member 131 capable of blocking air sent to the levitation nozzle 15a is arranged in the levitation air chamber portion 130a. Further, the separation shutter member 132 capable of blocking the air sent to the separation nozzle 16a is arranged in the separation air chamber portion 130b. Both the floating shutter member 131 and the separation shutter member 132 are plate-shaped members and are attached to the rotating shaft 133.

An arm member 137 extending in a direction orthogonal to the axial direction of the rotating shaft is attached to the rotating shaft 133. The rotation shaft 133 is attached to substantially the center of the arm member 137, and a shutter solenoid 136 is connected to one end of the arm member 137 via a connecting member 134. A spring 135 is attached to the other end of the arm member 137 to urge the arm member 137 downward in the drawing.

When the shutter solenoid 136 is not driven, as shown in FIG. 6, the levitation shutter member 131 and the separation shutter member 132 are located in the open position due to the urging force of the spring 135. When the shutter solenoid 136 is driven to move the connecting member 134 downward in the drawing against the urging force of the spring 135, one end side (the side to which the connecting member 134 is attached) of the arm member 137 is lowered. The arm member 137 rotates so that the other end side rises. The rotation of the arm member 137 causes the rotation shaft 133 to rotate, and the floating shutter member 131 and the separation shutter member 132 rotate. Then, when the floating shutter member 131 and the separation shutter member 132 are positioned at the closed positions after rotating 90 degrees from the state shown in FIG. 6, the movement of the connecting member 134 is stopped. As a result, the blowing of the floating air and the separated air is stopped.

FIG. 7 is a block diagram showing an example of the main configuration of the control system in the image forming apparatus 100. In the figure, a paper detection sensor 31 that detects the upper surface of a paper bundle placed on the paper loading platform 11 is connected to the control unit 66 as a control means of the paper feed device 200. The paper detection sensor 31 is arranged at a position where the upper surface of the paper bundle placed on the paper loading platform 11 can be detected when the distance from the suction belt 21 is within a specified range. ing.

In addition, a blower 17 and a suction device 23 that blow air onto the paper above the paper bundle P are also connected. Further, a shutter solenoid 136 for opening and closing the air shutter and an elevating drive motor 65 included in the elevating device 19 for elevating and lowering the paper loading platform 11 are also connected. Further, the control unit 66 of the paper feed device 200 is connected to the host controller 67 of the image forming device 100. Various devices of the image forming apparatus 100, such as the operation unit 124, are connected to the host controller 67.

FIG. 8 is a diagram illustrating a paper feeding operation.
When a command to start feeding paper is received from the host controller of the image forming apparatus 100 main body, the control unit 66 drives the elevating drive motor 65 to raise the paper loading platform 11. Then, when the paper detection sensor 31 detects the upper surface of the paper bundle, the drive of the elevating drive motor 65 is stopped. Next, the blower of the blower device 17 is started with the suction belt 21 stopped, and the blowing control is started. In addition, the suction of the suction device 23 is started, and the suction control is started. By starting the blowing of the blower device 17, as shown in FIG. 8A, the floating air, the separating air, and the side air are blown from the floating nozzle 15a, the separation nozzle 16a, and the side nozzle to the front end portion of the upper part of the paper bundle. Be done.

The front edges of a plurality of sheets of paper on the upper part of the paper bundle are lifted by blowing the floating air and the side air, a negative pressure is generated downward by the suction of the suction device 23, and the floating top-level paper P1 is attracted to the suction belt 21. To do.

As shown in FIG. 8B, when the top-level paper P1 is attracted to the suction belt 21, separation air is blown from the separation nozzle 16a between the top-level paper P1 and the second paper P2. Only the front side of the paper is levitated by side air or levitation air, and on the back side of the paper, the top paper and the second paper are in close contact with each other. However, by blowing the separation air between the top paper and the second paper in this way, the separation air flows toward the upstream side in the paper transport direction and separates the top paper from the second paper. I will do it.

As shown in FIG. 8C, the spray control is continued until the separation air reaches the rear edge of the paper. As shown in FIG. 8D, the separation air lifts the uppermost paper P1 from the second sheet to the rear end, and when the separation is completed, the shutter solenoid 136 is driven. As a result, the levitation shutter member 131 and the separation shutter member 132 move to the closed position, and the blowing of the levitation air and the separation air is stopped. Further, the driving of the side blower 14a is stopped, and the blowing of the side air is stopped. As a result, the spray control is completed (FIG. 8e). Next, as shown in FIG. 8 (f), the suction belt 21 is started to be driven while the suction device 23 is still operated. Then, the suction belt 21 moves on the surface in the arrow C direction (clockwise direction) in the drawing, and the top-level paper P1 sucked on the lower surface of the suction belt 21 is conveyed toward the downstream side in the transfer direction. Then, when the transfer roller pair 8 is reached and the transfer roller pair 8 rotates in the direction of the arrow G in the drawing, the top paper P1 is conveyed further toward the downstream side. When the top-level paper P1 is conveyed by the transfer roller pair 8, the drive of the suction belt 21 is stopped. In the case of continuous paper feeding, the steps of FIGS. 8 (a) to 8 (f) above are repeated.

In the present embodiment, when the top paper P1 is conveyed, the blowing of air is stopped and the top paper other than the top paper is dropped onto the sheet bundle to prevent the occurrence of double feeding. Further, when the spraying of air is temporarily stopped, the paper detection sensor 31 detects the upper surface of the paper bundle and controls the raising of the paper loading platform 11, so that the height of the sheet bundle can be detected accurately. , It is preferable that the ascending control of the paper loading platform 11 can be performed accurately.

Further, in the present embodiment, the wind speeds (air volumes) of the floating air, the separated air, and the side air are changed according to the paper thickness of the paper set in the paper feed tray 10 and the paper size. Table 1 below shows an example of the relationship between the paper thickness and the paper length and the PWM input signal which is a drive signal input to the floating blower 15, the separation blower 16, and the side blower 14a.

As shown in Table 1, the thicker the paper, the higher the duty (%) of the PWM input signal and the faster the wind speed (more air volume). This is because the thicker the paper, the heavier the paper, so a large amount of work is required to levitate the paper. Therefore, by increasing the duty (%) of the PWM input signal and increasing the wind speed, the wind energy of the floating air and the side air can be increased, and even a thick paper can be satisfactorily floated. As a result, even when thick paper is loaded, the top-level paper can be satisfactorily sucked onto the suction belt 21. As for the separated air, by increasing the wind speed, the air flows to the rear end of the paper, and the uppermost paper P1 can be separated from the second paper P2 to the rear end.

Further, in the paper thickness 2, the duty ratio when the paper length is medium size or more is higher than the duty ratio when the paper length is small size. This is because the longer the paper, the more work is required to separate the top sheet from the second sheet, which requires higher wind energy. Therefore, by making the duty ratio when the paper length is medium size or larger higher than the duty ratio when the paper length is small size, the top sheet P1 can be satisfactorily separated from the second sheet.

The information on the paper to be loaded on the paper feed tray 10 is, for example, the information on the paper loaded on the display unit of the operation unit 124 when the paper feed tray 10 is pulled out from the main body of the apparatus and the paper is loaded in the paper feed tray 10. Display prompting for information. Based on the display, the user operates the operation panel 123 to input the paper information to acquire the paper information. Then, the acquired paper information is associated with the paper feed tray 10 and stored in the non-volatile memory. When feeding paper, paper information is acquired from the non-volatile memory, and the duty ratio of the PWM input signal input to the floating blower 15, the separation blower 16, and the side blower 14a is set based on the acquired paper information.

In Table 1 above, the duty ratios of the PWM input signals input to the floating blower 15, the separation blower 16, and the side blower 14a are set to be the same, but the duty ratio is set for each of the floating blower 15, the separation blower 16, and the side blower 14a. You may.

In addition, the adhesion of the paper differs depending on the paper type. For example, coated paper and film paper are more likely to adhere to each other due to static electricity than uncoated paper, and have stronger adhesion between sheets than uncoated paper. Therefore, for paper types with strong adhesion such as coated paper and film paper, a large amount of work is required to levitate them, and high wind energy is required. Therefore, the duty ratio of the PWM input signal input to the floating blower 15, the separation blower 16, and the side blower 14a may be changed depending on the paper type set in the paper feed tray 10. Specifically, in the case of a paper type such as coated paper or film paper having a strong adhesion between papers, the duty ratio is increased to increase the wind speed (increase the air volume). As a result, even if the paper has a strong adhesion between the papers, the leading end side of the paper can be satisfactorily floated by the levitation air and the side air, and the top-level paper P1 can be adsorbed on the suction belt 21. Further, the separation air can separate the uppermost paper P1 from the second paper P2 up to the rear end, and can suppress the occurrence of double feeding and non-feeding.

Further, the paper feed device 200 of the present embodiment expands the length of the paper feed tray 10 in the paper transport direction by attaching an expansion cartridge, and mounts a long paper having a paper length longer than A3 length (487 mm). It is possible.

9 (a) is a perspective view showing the paper feed device 200 to which the expansion cartridge 210 is not attached, and FIG. 9 (b) is a perspective view showing the paper feed device 200 to which the expansion cartridge 210 is attached.
As shown in FIG. 9A, the housing 200a of the paper feeding device 200 is composed of a frame and a plurality of panels 201, 202 attached to the frame, and has a box shape. The paper feed tray 10 is configured to be retractable toward the front side in the drawing with respect to the housing 200a, and the paper feed tray 10 can be pulled out toward the front side in the drawing by the user holding the handle portion 10a. It can be withdrawn from 200a. By pulling out the paper feed tray 10, the paper P can be loaded and unloaded.

Panels 201 and 202 are attached to the upper and lower ends of the housing 200a on the upstream side in the transport direction. Of these, the upper panel 201 is detachably attached to the housing 200a with screws. The panel 201 is removed and an expansion cartridge 210 is attached as shown in FIG. 9B.

FIG. 10A is a perspective view showing the paper feed tray 10 and the expansion cartridge 210, and FIG. 10B is a view showing a state in which the opening / closing cover 212 of the expansion cartridge 210 is opened.
The expansion cartridge 210 includes a long base 211 fixed to the housing 200a, an extension loading base 213 fixed to the paper loading base 11, an extension end fence 214, an opening / closing cover 212, and the like. The long base 211 is detachably fixed to the housing 200a with screws or the like, and is arranged on the lower surface of the extension loading base 213. The extension end fence 214 is magnetically attached to the long base 211. Specifically, the extension end fence 214 is provided with a magnet at the base mounted on the long base 211, and the long base 211 is provided with a metal plate or a magnet to which the magnet is attracted. ing. As a result, the extension end fence 214 can be detachably fixed at a position corresponding to the length of the long paper. When the expansion cartridge 210 is attached, the end fence 25 provided on the paper feed tray 10 is removed. The opening / closing cover 212 is rotatably attached by a hinge provided on the back side of the long base 211. When the expansion cartridge 210 is attached, the open / close cover 212 is opened and long paper is set in the paper feed tray 10.

FIG. 11 is a diagram illustrating attachment of the extension loading platform 213.
As shown in FIG. 11A, a plurality of screw holes 11a for attaching the extension loading platform 213 are provided at the upstream end of the paper loading platform 11 in the sheet transport direction. The extension loading platform 213 is fastened to the paper loading platform 11 by screwing a screw into the screw hole 11a. As a result, the paper loading platform is extended, and long paper can be loaded.

FIG. 12 is a diagram illustrating a set of paper when the expansion cartridge 210 is attached.
When the expansion cartridge 210 is attached, since the extension loading platform 213 is fixed to the paper loading platform 11, the paper feed tray 10 cannot be pulled out to the front side, and the paper feed tray 10 is pulled out to the front side to cover the paper. I can't set. Therefore, when the expansion cartridge is attached, the open / close cover 212 of the expansion cartridge 210 is opened to set the paper.

As shown in FIG. 12A, a paper loading platform lowering switch 215 is provided on the front side surface of the expansion cartridge 210. When the paper feed tray 10 is pulled out toward the front side, the drive connection between the elevating device 19 and the paper loading platform 11 is disconnected, and the paper loading platform 11 naturally lowers due to the weight of the paper loading platform 11. However, when the expansion cartridge 210 is attached, the paper feed tray 10 cannot be pulled out toward the front side, so that the drive connection between the elevating device 19 and the paper loading platform 11 cannot be disconnected. Therefore, even if the open / close cover 212 is opened, the paper loading platform is located at the raised position and the paper cannot be set. Therefore, when the expansion cartridge 210 is attached, the paper loading platform lowering switch 215 is operated to lower the paper loading platform 11 to the minimum lowered position before opening the open / close cover 212. For example, the control unit 66 may display a message prompting the operation display unit to replenish the paper and a message prompting the user to press the paper loading platform lowering switch 215 when the paper on the paper loading platform 11 runs out.

After operating the paper loading platform lowering switch 215 to lower the paper loading platform to the lowest position, grasp the handle 216 provided on the opening / closing cover 212 and open the opening / closing cover as shown in FIG. 12 (b). The inside of the paper feed tray 10 is exposed. Then, as shown in FIG. 12C, when the long paper bundle PN is placed on the paper loading platform 11, the open / close cover 212 is closed. As a result, the long paper bundle is set in the paper feed tray 10. Further, an open / close detection sensor for detecting the opening / closing of the open / close cover 212 is provided, and when the open / close detection sensor detects that the open / close cover 212 is closed, the elevating drive motor 65 is driven and the paper detection sensor 31 is used for the paper bundle. It may be raised to a position where the upper surface of the is detected. As a result, the first paper feed after the paper is set can be quickly performed.

When the expansion cartridge 210 is attached and the long paper is set in the paper feed tray 10, at least the wind energy of the separation air blown out from the separation nozzle 16a is increased. This is because long paper is long in the sheet transport direction, so the amount of work required to levitate the top long paper to the rear end with separation air increases. Therefore, unless the expansion cartridge 210 is attached and the wind energy of the separation air is increased when the long paper is set, the separation air stalls in the middle and cannot reach the rear end of the long paper, and is the highest length. The rear edge side of the length paper does not separate from the second length paper. As a result, for example, when the tip of the second paper dropped on the stack of paper is located downstream of the front wall of the paper feed tray 10 in the sheet transport direction, the second paper is fed together with the top paper. Double feeding may occur. Further, when the tip of the second paper dropped on the stack of paper is located upstream of the front wall portion of the paper feed tray 10 in the sheet transport direction, the second paper hinders the transport of the top sheet. , There is a risk of non-feeding.

As shown in Table 1 above, in the present embodiment, the duty ratio of the PWM input signal is set to 90% when the paper is thick, and there is little margin for increasing the duty ratio. Therefore, in the present embodiment, when the expansion cartridge 210 is attached and the long paper is set in the paper feed tray 10, the blowing time is lengthened and the total wind energy of the separated air is increased to increase the length. The scale paper was separated to the rear end.

FIG. 13 is a control flow diagram of the air blowing setting of the present embodiment.
As shown in FIG. 13, the control unit 66 sets the duty ratio of the PWM input signal input to the floating blower 15, the separation blower 16, and the side blower 14a based on the paper type information and the above Table 1 (S1). ). Next, the control unit 66 checks whether or not the paper loaded in the paper feed tray 10 is long paper (S2). For example, it may be determined whether or not long paper is set based on whether or not the expansion cartridge 210 is attached, or paper feeding is performed based on the paper information input to the user by the operation unit 124 or the like. It may be determined whether or not the paper loaded in the tray 10 is long paper. Then, when the long paper is set in the paper feed tray 10 (Yes in S2), the air blowing time is set based on the paper information (S3).

Table 2 below is a table showing an example of the relationship between the paper thickness, the paper size, and the air blowing time when long paper is set.

As shown in Table 2, the longer the length of the long paper, the longer the air blowing time (between the paper feed papers). By lengthening the air blowing time, it is possible to increase the wind energy of the separated air blown from the separation nozzle during air blowing control. As a result, the separation air ejected from the separation nozzle first during air blowing control is used to separate the top sheet and the second sheet, and even if it stalls, it is the separation air that is sent in later. The rear end side can also be separated. As a result, even a long paper can be satisfactorily separated from the second paper up to the rear end of the top paper by the separation air, and it is possible to suppress the occurrence of double feeding and non-feeding.

Further, as shown in Table 2, the thinner the paper thickness, the longer the air blowing time. This is because, in the case of thick paper, when the top paper is separated from the second paper to some extent by the separation air, it is lifted to the rear end by its own stiffness and can be separated to the rear end. However, in the case of thin paper with weak stiffness, it is necessary to float up to the rear edge of the paper with separation air, which requires a large amount of work. Therefore, the thinner the paper, the longer the spraying time and the more wind energy. As a result, even a long paper with a thin paper thickness can be separated from the second paper up to the rear end of the top-level paper, and non-feeding and double-feeding can be suppressed.

Further, as shown in Table 2, the narrower the paper width, the longer the air blowing time. This is because the narrower the paper width, the more the separation air escapes from the end in the paper width direction, and less air is used for separation. Therefore, the narrower the paper width, the longer the air blowing time, so that even a narrow long paper can be separated from the second paper up to the rear edge of the top paper, resulting in non-feeding or non-feeding. It is possible to suppress the occurrence of double feeding.

Further, for example, the stronger the paper-to-paper adhesion force such as coated paper or film paper, the longer the air blowing time may be. This is because the stronger the paper-to-paper adhesion force, the more work is required to separate the paper, and the higher the wind energy is required. Therefore, the stronger the paper-to-paper adhesion such as coated paper and film paper, the longer the air spraying time, so that even the long paper of the paper-to-paper type with strong inter-paper adhesion is after the top-level paper. It can be separated from the second paper up to the edge, and non-feeding and double feeding can be suppressed.

When the control unit 66 starts driving 14a, 15 and 16 of each blower, the timer is started, and when the spraying time set based on the paper information is reached, the shutter solenoid 136 is driven to separate the air and the floating air. Stop spraying. Further, the driving of the side blower 14a is stopped to stop the blowing of the side air. Then, the transfer of the sheet is started.

In the present embodiment, the spraying of the separated air, the floating air, and the side air is stopped when the sheet is conveyed by the paper feeding unit 20, but the separated air, the floating air, and the side air are constantly sprayed at the time of feeding. In the paper device, the set spraying time can be set by adjusting the sheet transfer timing.

Further, in the above, the blowing time is lengthened to increase the total wind energy of the separated air, but the Duty ratio is increased to increase the wind speed (air volume) to increase the wind energy per unit time. Therefore, the total wind energy may be increased. By increasing the wind speed (air volume) and increasing the wind energy, it is possible to suppress the expansion of the space between the papers, and there is an advantage that the decrease in productivity can be suppressed. On the other hand, when the blowing time is lengthened to increase the wind energy, there is an advantage that an increase in wind noise of the blower fan can be suppressed and the noise of the device can be suppressed.

Further, the wind energy may be increased by increasing the wind speed and lengthening the blowing time. Further, the driving time of only the separation blower 16 may be lengthened, and only the blowing time of the separation air may be lengthened.

Further, the blowing time and the air volume may be set by the operation of the operation unit 124 of the user. For example, when a paper feed failure such as double feeding or non-feeding occurs, the spraying time is lengthened or the air volume of the separation blower is increased by operating the operation unit 124 of the user. As a result, it is possible to suppress the occurrence of paper feed defects such as double feed and non-feed.

Further, depending on the user, it may be troublesome to operate the operation unit 124 to input the paper information. Therefore, the user may be able to set whether or not to perform spray control based on the paper information. When the user is set not to perform the spray control based on the paper information, for example, when the expansion cartridge 210 is not attached, the duty ratio of the PWM input signal input to each blower is set to 90%. As a result, no matter what kind of paper is set, the paper can be satisfactorily floated and separated. When the expansion cartridge is attached, the duty ratio of the PWM input signal input to each blower is set to 90%, and the spraying time is set to 3500 [ms]. As a result, no matter what kind of long paper is set, the paper can be satisfactorily floated and separated.

On the other hand, when the paper bundle does not require much wind energy for separation and ascent by setting the duty ratio of the PWM input signal input to the blower and the spraying time based on the paper information. There is an advantage that noise and power consumption can be suppressed, and a decrease in productivity can also be suppressed.

What has been described above is an example, and has a unique effect in each of the following aspects.
(Aspect 1)
A sheet loading unit such as a paper loading platform 11 for loading a sheet bundle such as a paper bundle P, a transport means such as a paper feed unit 20 for transporting the top sheet of the sheet bundle, and a blower for blowing air onto the sheet bundle. A sheet feeding device such as a paper feeding device 200 that is provided with an air blowing means such as 17 and can be attached with an expansion cartridge 210 that expands the length of the sheet loading portion in the sheet transport direction so that a long sheet can be mounted. In the above, the air blowing means blows air onto the upper sheet of the sheet bundle loaded on the sheet loading portion from at least the downstream side in the sheet transport direction, and at least two types of sheet bundles having different lengths in the sheet transport direction. , A control unit 66 that controls the air blowing means so that the wind energy of air for the sheet bundle having the longer sheet transport direction length is larger than the wind energy of air for the sheet bundle having the shorter sheet transport direction length. Equipped with control means such as.
The applicant has attached an expansion cartridge, and a long sheet (in this embodiment, a sheet having a paper length of 487.8 mm (A3 length) or more) is mounted on a sheet feeding device such as a paper feeding device 200. In some cases, as a result of diligent research on the causes of paper feed defects such as double feed and non-feed, the following was found. That is, the seat feeding device described in Patent Document 1 blows air in the seat width direction from the blowing port provided on the side fence. Therefore, as the size of the sheet increases, even if the spraying time is lengthened and the total wind energy in the blowing control is increased, the air from the blowing port provided on the side fence expands on the upstream side in the transport direction of the long sheet. It did not flow to the part housed in the cartridge, and the upstream side of the top long sheet in the sheet transport direction remained in close contact with the second long sheet. As a result, it was found that double feeding and non-feeding occurred.
Therefore, in the first aspect, the air blowing means blows air from at least the downstream side in the sheet transporting direction to the upper sheet of the sheet bundle loaded on the sheet loading portion. As a result, as described with reference to FIG. 8 above, the air blown onto the sheet bundle from the downstream side in the sheet transport direction enters at least between the uppermost sheet and the second sheet, and raises the uppermost sheet. While separating from the second sheet, it flows upstream in the sheet transport direction, and flows to the upstream end in the sheet transport direction of the top sheet, so that the upstream end of the top sheet flows from the second sheet. Can be separated. As a result, even when the expansion cartridge is attached and a long sheet that is long in the sheet transport direction is attached, air flows to the upstream end in the sheet transport direction, and the topmost long sheet is extended to the upstream end in the sheet transport direction. It can be separated from the second long sheet.
In addition, as the length of the sheet in the sheet transport direction increases, the amount of work required to lift the top sheet to the upstream end in the sheet transport direction increases, and the wind energy of the air blown to the sheet bundle by the air blowing means is required. Become. Therefore, in the first aspect, the wind energy of air for a sheet bundle having a long sheet transport direction length is made larger than the air wind energy for a sheet bundle having a short sheet transport direction length. As a result, even when a bundle of long sheets is loaded, the air blown between the uppermost long sheet and the second long sheet can flow to the upstream end in the sheet transport direction. It is possible to separate the upper long sheet from the second long sheet up to the upstream end in the sheet transport direction. Further, in the case of a sheet having a short sheet transport direction length, power consumption can be suppressed by reducing the wind energy.
The sheet includes paper, coated paper, label paper, OHP sheet, film and the like.

(Aspect 2)
In the first aspect, the control means such as the control unit 66 makes the wind energy of air for a long sheet bundle composed of long sheets from the wind energy of air for a normal sheet bundle (a sheet that can be mounted without the expansion cartridge 210). Also increase.
According to this, as described in the embodiment, the uppermost long sheet can be separated from the second long sheet by air up to the upstream end in the sheet transport direction, and double feeding or non-feeding can occur. It can be suppressed from occurring. Further, by making the wind energy of the normal sheet smaller than that of the long sheet, the power consumption can be reduced as compared with the case where the same wind energy as that of the long sheet is used.

(Aspect 3)
In aspects 1 or 2, the control means, such as the control unit 66, adjusts the air blowing time to adjust the wind energy.
According to this, as described in the embodiment, the longer the air blowing time, the more the wind energy at the time of blowing control can be increased, and the air is flowed to the upstream end in the sheet transport direction of the long sheet. , The top sheet and the second sheet can be separated. Further, by adjusting the air blowing time, it is possible to suppress an increase in noise as compared with the case where the wind speed is adjusted.

(Aspect 4)
In the third aspect, the control unit 66 adjusts the air blowing time by adjusting the timing of transporting the top sheet of the transport means such as the paper feed unit 20.
According to this, as described in the embodiment, the air blowing time can be adjusted without temporarily stopping the air blowing.

(Aspect 5)
In the third aspect, the air blowing means such as the blower 17 is composed of an air blocking means (in the present embodiment, a separation shutter member 132, a shutter solenoid 136, etc.) for blocking air blowing from the downstream side in the sheet transport direction to the sheet bundle. ), And the control means such as the control unit 66 adjusts the air blowing time by controlling the timing of shutting off the air blowing by the air shutting means.
According to this, as described in the embodiment, when the set air blowing time is reached, the air blowing is stopped on the sheet bundle by the air blocking means, so that the air blowing is stopped and the set air blowing time is reached. Can be.

(Aspect 6)
In any one of aspects 1 to 5, the control means such as the control unit 66 adjusts the wind speed of the air to adjust the wind energy.
According to this, unlike the case where the wind energy is adjusted by the blowing time, the space between the papers does not widen as described in the embodiment. Therefore, wind energy can be increased without compromising productivity.

(Aspect 7)
In any one of aspects 1 to 6, the control means such as the control unit 66 is based on at least one of the width, paper type, and paper thickness of the sheet mounted on the sheet loading unit such as the paper loading platform 11. To adjust.
According to this, as described in the embodiment, the upper sheet of the sheet bundle can be satisfactorily floated, and the uppermost sheet and the second sheet are separated to the upstream end in the sheet transport direction. Can be done.

(Aspect 8)
In the seventh aspect, the control means such as the control unit 66 adjusts the wind energy of the air based on the width of the sheet mounted on the sheet loading unit such as the paper loading platform 11. For at least two types of sheet bundles having different sheet widths, the wind energy of air for the sheet bundle having the wider sheet width is made smaller than the wind energy of air for the sheet bundle having the narrower sheet width.
According to this, as described in the embodiment, as the seat width becomes narrower, the air that has flowed between the uppermost seat and the second seat escapes from the end portion in the seat width direction, and less air is used for separation. Become. Therefore, by increasing the wind energy in inverse proportion to the sheet width, even if the sheet width is narrow, the top sheet and the second sheet can be satisfactorily separated up to the upstream end in the sheet transport direction.

(Aspect 9)
In the seventh or eighth aspect, the control means such as the control unit 66 adjusts the wind energy of the air based on the paper type of the sheet mounted on the sheet loading unit such as the paper loading platform 11. The control means such as 66 uses the wind energy of the air for the sheet bundle having the stronger sheet-to-sheet adhesion and the air to the sheet bundle having the weaker sheet-to-sheet adhesion for at least two types of sheet bundles having different sheet-to-sheet adhesion. Greater than the wind energy of.
According to this, as described in the embodiment, a paper type having a stronger adhesive force between sheets such as coated paper requires a larger amount of work to separate. Therefore, by increasing the wind energy in the case of a sheet bundle made of a paper type with strong sheet-to-sheet adhesion, even if the paper type has strong sheet-to-sheet adhesion, the top sheet and the second sheet up to the upstream end in the sheet transport direction. It can be separated from the sheet well.

(Aspect 10)
In any of aspects 1 to 9, the wind energy of the air can be set by the user.
According to this, as described in the embodiment, when a paper feed failure such as double feed or non-feed occurs, the user increases the wind energy at the time of air blowing control, so that the paper feed failure occurs. Can be suppressed.

(Aspect 11)
In any one of aspects 1 to 10, control for adjusting the wind energy of air based on at least one of a sheet length, a sheet width, a paper type, and a paper thickness mounted on a sheet loading unit such as a paper loading platform 11. Can be set by the user as to whether or not to perform.
According to this, as described in the embodiment, if the control for adjusting the wind energy of the air is not performed, the user does not have to input the seat information. As a result, it is possible to meet the needs of both users who find it troublesome to input sheet information and users who want to reduce power consumption, and it is possible to provide a device with high usability.

(Aspect 12)
In any one of aspects 1 to 11, the transporting means such as the paper feed unit 20 sucks the top sheet of the floating sheet floated by the air blowing means such as the blower 17, and transports the sucked sheet. The spraying means includes a levitation air ejection port such as a levitation nozzle 15a for blowing air onto the upper sheet of the sheet bundle from the downstream side in the sheet transport direction, and a top sheet from the downstream side in the sheet transfer direction. Air is blown between the second sheet and the separation nozzle 16a for separating the uppermost sheet and the second sheet, and air is blown to the upper sheet of the sheet bundle from the sheet width direction. It is equipped with a side air outlet such as a side nozzle for floating the upper seat.
According to this, the upper sheet of the sheet bundle can be satisfactorily floated, the uppermost sheet can be adsorbed on the conveying means, and the uppermost sheet and the second sheet can be separated well.

(Aspect 13)
An image forming system 1 or the like including an image forming means such as an image forming apparatus 100 for forming an image on a sheet such as paper and a feeding means such as a paper feeding device 200 for feeding the sheet to the image forming means. In the image forming apparatus, the paper feeding device according to any one of aspects 1 to 9 was used as the paper feeding means.
According to this, poor feeding can be suppressed.

1: Image forming system 10: Paper feed tray 10a: Handle 11: Paper loading platform 12: Front blower 13: Side fence 13a: Discharge port 14: Side blower 14a: Side blower 15: Floating blower 15a: Floating nozzle 16 : Separation blower 16a: Separation nozzle 17: Blower 19: Elevating device 20: Paper feed unit 21: Suction belt 22a, 22b: Stretch roller 23: Suction device 25: End fence 31: Paper detection sensor 63: Open / close cover 65: Elevating drive motor 66: Control unit 100: Image forming device 122: Display unit 123: Operation panel 124: Operation unit 130: Air chamber 130a: Floating air chamber unit 130b: Separation air chamber unit 131: Floating shutter member 132: Separation shutter member 133: Rotating shaft 134: Connecting member 135: Spring 136: Shutter solenoid 137: Arm member 200: Paper feeding device 200a: Housing 210: Expansion cartridge 211: Long stand 212: Open / close cover 213: Extension loading stand 214: Extension End fence 215: Paper loading platform lowering switch 216: Handle

JP-A-2009-91074

Claims (12)

A seat loading section for loading a bundle of seats and
A transport means for transporting the top sheet of the sheet bundle, and
The sheet bundle is provided with an air blowing means for blowing air.
In a sheet feeding device to which an expansion cartridge can be attached to extend the length of the sheet loading section in the sheet transport direction so that a long sheet can be mounted.
The air blowing means blows air from at least the downstream side in the sheet transporting direction to the upper sheet of the sheet bundle loaded on the sheet loading portion.
For at least two types of sheet bundles having different lengths in the sheet transport direction, the wind energy of air for the sheet bundle having the longer sheet transport direction length is higher than the wind energy of air for the sheet bundle having the shorter sheet transport direction length. as also increased, and control means for controlling the air blowing means,
The control means is a sheet feeding device characterized in that the air blowing time is adjusted to adjust the wind energy . In the sheet feeding device according to claim 1,
The control means is a sheet feeding device characterized in that the wind energy of air for a long sheet bundle made of long sheets is made larger than the wind energy of air for a normal sheet bundle . A sheet feeding apparatus according to請Motomeko 1 or 2,
The control means is a sheet feeding device characterized in that the air blowing time is adjusted by adjusting the timing of transporting the top sheet of the transport means. In the sheet feeding device according to claim 1 or 2 .
The air blowing means includes an air blocking means for blocking air blowing from the downstream side in the sheet transport direction to the sheet bundle.
The control means, by controlling the motor imino ring for blocking the air blowing by the air shutoff means, a sheet feeding apparatus and adjusting the air blowing time. In the sheet feeding device according to any one of claims 1 to 4 .
The control means is a seat feeding device characterized in that the wind speed of air is also adjusted to adjust the wind energy. In the sheet feeding device according to any one of claims 1 to 5 ,
The control means is a sheet feeding device that adjusts the wind energy of air based on at least one of the width, paper type, and paper thickness of the sheet mounted on the sheet loading unit. In the sheet feeding device according to claim 6 ,
The control means adjusts the wind energy of the air based on the width of the seat mounted on the seat loading portion.
The control means makes the wind energy of air for a seat bundle having a wider seat width smaller than the wind energy of air for a seat bundle having a narrower seat width for at least two types of seat bundles having different seat widths. A sheet feeding device characterized by. In the sheet feeding device according to claim 6 or 7 .
The control means adjusts the wind energy of air based on the paper type of the sheet mounted on the sheet loading unit.
For at least two types of sheet bundles having different sheet-to-seat adhesions, the control means receives air wind energy for the sheet bundle having stronger sheet-to-sheet adhesion and air wind power to the sheet bundle having weaker sheet-to-sheet adhesion. A sheet feeder characterized by making it larger than energy. A sheet feeding apparatus according to any of claims 1 to 8 have shifted,
A seat feeding device characterized in that the wind energy of the air can be set by a user. In the sheet feeding device according to any one of claims 1 to 9 .
The user can set whether or not to control the adjustment of the wind energy of the air based on at least one of the length of the sheet mounted on the sheet loading unit, the width of the sheet, the paper type, and the paper thickness. A sheet feeding device characterized by that. In the sheet feeding device according to any one of claims 1 to 10 .
The transporting means adsorbs the uppermost sheet of the floating sheet floated by the air blowing means and transports the adsorbed sheet.
The air blowing means blows air from the downstream side in the sheet transport direction to the upper sheet of the sheet bundle to float the upper sheet, and the uppermost sheet and the second sheet from the downstream side in the sheet transfer direction. Air is blown between and the air outlet for separation to separate the top sheet and the second sheet, and the side for blowing air from the seat width direction to the upper sheet of the sheet bundle to raise the upper sheet. A seat feeding device characterized by having an air outlet. The method according to any one of claims 1 to 11 in an image forming apparatus including an image forming means for forming an image on a sheet and a feeding means for feeding the sheet to the image forming means. An image forming apparatus characterized by using a sheet feeding device.

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