JP2022026579A - Sheet feeder and image forming apparatus - Google Patents

Abstract

To provide a sheet feeder allowed to be compatible with broad types of sheets from a thin paper to a thick paper and to normally feed a sheet even if any type of a sheet is used.SOLUTION: A sheet feeder 5 comprises a sheet loading unit 6 that can ascend/descend in a state of loading a sheet bundle 9, a pickup roller 30 that can vertically move in contact with an uppermost surface of the sheet bundle 9 with ascending/descending of the sheet loading unit 6 and feeds a sheet of the sheet bundle 9 downstream in a transport direction, a roller pair 40 that if a plurality of sheets are fed by the pickup roller 30, feeds a first sheet downstream in the transport direction and regulates a second sheet and the subsequent from moving, a sorting member 50 that restricts the number of sheets to be carried from the pickup roller 30 to the roller pair 40, and a control unit 60 that determines the height position of the pickup roller 30 depending on a type of the sheet placed on the sheet loading unit 6 and drives the sheet loading unit 6 to rise/lower.SELECTED DRAWING: Figure 3

Description

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

Conventionally, an image forming apparatus such as a printer or an MFP (Multifunction Peripherals) includes a sheet supply device for loading a sheet bundle such as printing paper and supplying and transporting a sheet from the sheet bundle (for example, Patent Document 1). The seat supply device includes a seat loading unit for loading a bundle of seats, and a pickup roller located above the seat loading unit and delivering the seat to the downstream side in the transport direction. The pickup roller contacts and rotates the sheet on the uppermost surface of the sheet bundle, so that the sheet is sent out to the downstream side in the transport direction.

However, it is possible that a plurality of sheets on the upper part of the sheet bundle are double-fed at the same time by the pickup roller. In order to eliminate this double feeding, a roller pair consisting of a paper feed roller and a separation roller is arranged on the downstream side of the pickup roller. When multiple sheets are sent out from the pickup roller, the roller pair transports the first sheet at the top to the downstream side in the transport direction, and the second and subsequent sheets advance to the downstream side in the transport direction. To regulate.

However, when a large number of sheets are double-fed by the pickup roller at the same time, the roller pair may not be able to stop the progress of all of the second and subsequent sheets. In this case, among the large number of sheets sent out by the pickup rollers, the plurality of sheets located at the upper part are conveyed to the downstream side of the roller pair, which causes jam. In order to prevent the occurrence of such jams, in the conventional sheet supply device, a handling member having an inclined surface with respect to the transport direction is provided between the pickup roller and the roller pair, and the sheet is repeatedly fed from the pickup roller. By pressing the tip of the sheet against the inclined surface of the handling member, it is possible to prevent a large number of sheets from being repeatedly fed to the roller pair.

The handling member can effectively prevent a large number of sheets from being repeatedly fed to the roller pair when the sheets are thin paper. That is, when the sheet is thin paper, the handling member conveys only a few sheets on the upper layer of the many sheets sent out from the pickup roller along the inclined surface, and the roller pair on the downstream side. Can be supplied to.

On the other hand, in the case of a sheet having a certain rigidity or more such as thick paper, the handling member does not function normally. That is, when the sheet is thick paper, when the tip of the sheet sent out by the pickup roller comes into contact with the handling member, the transport resistance that the sheet receives from the handling member increases. Therefore, the pickup roller cannot convey the sheet to the downstream side along the inclined surface, and a transfer defect is likely to occur. For example, by making the angle of the inclined surface of the handling member close to parallel to the transport direction, the transport resistance of a sheet such as thick paper can be reduced, so that transport defects are less likely to occur. This will reduce the effective double feed prevention function.

In an image forming apparatus, thin paper or plain paper is generally used more frequently than thick paper is used, so that when thin paper or plain paper is used, a large number of sheets should not be double-fed. It is necessary to set the angle of the inclined surface of the handling member. As a result, when a sheet such as thick paper having a rigidity of a certain level or higher is used, there is a problem that transport defects are likely to occur.

In addition, when a restricting member cannot be provided on the rear end side of the sheet like a manual feed tray, the sheet loading section is angled to the rear of the sheet in order to prevent the sheet from retracting due to the sheet feeding operation. Many structures are used for loading with the end side lifted. In this case, since it is easier for the seat to enter the downstream roller pair at an angle closer to horizontal at the lower position of the pickup roller, the seat loading portion has a structure that supports the seat front end side and the seat rear end side at different angles. Will be. In the case of thin paper or plain paper, the rigidity of the sheet is low, so the sheet bundle is loaded in a shape along the angle of the sheet loading portion. On the other hand, in the case of thick paper, only the front end and the rear end of the sheet touch the bottom surface of the sheet loading portion, and the center portion of the sheet is loaded in a state of floating from the bottom surface. Therefore, when the sheet is fed out by the pickup roller, the sheet is no longer parallel to the transport direction, and the sheet comes into contact with the inclined surface of the handling member at an angle close to a right angle, and the transfer resistance becomes even higher. There is also the problem of getting rid of it.

Further, the pickup roller is configured to generate a constant frictional force by contacting the uppermost surface of the sheet bundle with a predetermined pressing force to send the sheet to the downstream side in the transport direction. However, in the case of thick paper, if the central part of the sheet is floating from the bottom surface, the pressing force of the pickup roller is absorbed by bending the sheet, and the frictional force required to convey the sheet is applied. There is also a problem that it cannot be obtained and causes a transport defect.

Japanese Unexamined Patent Publication No. 2005-187145

The present invention has been made to solve the above-mentioned conventional problems, supports a wide range of sheet types from thin paper to thick paper, and feed performance regardless of the type of sheet used. It is an object of the present invention to provide a sheet supply device and an image forming device capable of ensuring the above.

In order to achieve the above object, the invention according to claim 1 is a sheet supply device, in which the sheet loading portion that can move up and down with the sheet bundle loaded and the sheet in contact with the uppermost surface of the sheet bundle. It can move up and down as the loading unit moves up and down, and is installed on the pickup roller that sends out the sheets of the sheet bundle to the downstream side in the transport direction and on the downstream side of the pickup roller in the transport direction. A roller that separates the first sheet from the second and subsequent sheets, supplies the first sheet to the downstream side in the transport direction, and regulates the movement of the second and subsequent sheets. A pair, a handling member arranged between the pickup roller and the roller pair, which comes into contact with the tip of a sheet sent out from the pickup roller and limits the number of sheets transported to the roller pair, and a sheet loading unit. The configuration is characterized in that the height position of the pickup roller is determined according to the type of the seat loaded on the vehicle, and the control means for raising and lowering the seat loading unit so as to be at the height position is provided. ..

The invention according to claim 2 is the sheet supply device according to claim 1, wherein the control means determines the type of sheet based on the rigidity or basis weight of the sheet.

According to a third aspect of the present invention, in the sheet supply device of the first or second aspect, the control means sets the height position of the pickup roller to thin paper or thin paper when the sheet loaded on the sheet loading unit is thick paper. The configuration is characterized in that the position is determined to be higher than that of plain paper.

The invention according to claim 4 further comprises an urging means for urging the pickup roller toward a bundle of sheets loaded on the sheet loading unit in the sheet feeding device according to any one of claims 1 to 3. It is a characteristic configuration.

The invention according to claim 5 is the sheet feeding device according to any one of claims 1 to 3, wherein the handling member is directed from the upstream side to the downstream side in the sheet transport path between the pickup roller and the roller pair. The control means has an inclined guide portion whose height is gradually increased, and when the sheet loaded on the sheet loading portion is thin paper or plain paper, the height position of the pickup roller is set to the guide portion. When the sheet is determined to be a first position lower than the upper end position and the sheet loaded on the sheet loading portion is thick paper, the height position of the pickup roller is set to a position higher than the first position and the guide. The configuration is characterized in that it is determined to be a second position near the upper end position of the portion.

The invention according to claim 6 further comprises an urging means for urging the pickup roller toward a bundle of sheets loaded on the sheet loading portion in the sheet supply device according to claim 5. The configuration is characterized in that the urging force when the pickup roller is in the second position is stronger than the urging force when the pickup roller is in the first position.

According to a seventh aspect of the present invention, in the seat supply device of the sixth aspect, the urging means does not urge the pickup roller when the pickup roller is in the first position, and the pickup roller is the first. The configuration is characterized in that the pickup roller is urged when it is in the position of 2.

According to a eighth aspect of the present invention, in the sheet feeding device of the fourth, sixth or seventh aspect, the urging means increases the urging force non-linearly as the height position of the pickup roller increases. It is a characteristic configuration.

The invention according to claim 9 is the seat feeding device according to claim 4, wherein the urging means is composed of a coil spring.

According to a tenth aspect of the present invention, in the seat supply device according to any one of claims 1 to 9, the seat loading portion has an inclined surface whose height position increases from the front end position to the rear end position of the seat. It is a configuration characterized by.

The invention according to claim 11 is an image forming apparatus, and is characterized by comprising the sheet supply apparatus according to any one of claims 1 to 10.

According to the present invention, it is possible to support a wide range of sheet types from thin paper to thick paper, and to maintain good paper feed performance regardless of the type of sheet used.

It is a figure which shows an example of the image forming apparatus which mounts a sheet supply apparatus. It is a side view which shows one configuration example of the sheet supply device provided as a manual feed tray. It is a side view which shows one aspect of the sheet supply device when a sheet such as thin paper is fed by a pickup roller. It is an enlarged view which shows the pickup roller, the roller pair, and the handling member when a sheet such as thin paper is fed. It is a side view which shows the sheet supply device in the state which the sheet with high rigidity such as a thick paper is loaded on the sheet loading part. It is a figure which illustrates the state in which a pickup roller is in contact with a sheet such as thick paper. It is an enlarged view which shows the state which the height position of the pickup roller reached the 1st position in the state which the sheet such as a cardboard is loaded. It is an enlarged view which shows the pickup roller, the roller pair, and the handling member when a sheet with high rigidity such as thick paper is fed. It is a figure which shows the example of the change of the urging force of the urging member. It is a block diagram which shows an example of the control mechanism of an image forming apparatus. It is a flowchart which shows an example of the processing procedure which controls the operation of a sheet supply device. It is a figure which shows the example of the operation screen displayed on the display part of the operation panel.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the embodiments described below, the elements common to each other are designated by the same reference numerals, and duplicate description thereof will be omitted.

FIG. 1 is a diagram showing a configuration example of an image forming apparatus 1 according to an embodiment of the present invention. This image forming apparatus is configured as an MFP having a plurality of functions such as a copy function, a scan function, and a print function. The image forming apparatus 1 has an image forming unit 2 in the central portion of the main body of the apparatus, and has a paper feeding unit 3 provided with a plurality of paper feed trays 3a, 3b, 3c, 3d in the lower portion of the image forming unit 2. is doing. Each of the plurality of paper feed trays 3a, 3b, 3c, and 3d accommodates a bundle of sheets on which sheets such as printing paper are stacked. The paper feed unit 3 feeds sheets one by one from any one of the plurality of paper feed trays 3a, 3b, 3c, and 3d and supplies them to the image forming unit 2. The image forming unit 2 forms an image on the sheet fed from the paper feeding unit 3 by, for example, an electrophotographic method, and ejects the sheet on which the image is printed on the upper paper ejection tray 2a.

Further, the image forming apparatus 1 is provided with a manual feed tray 4 on the side surface of the apparatus main body. The manual feed tray 4 can be opened and closed with respect to the side surface of the apparatus main body. FIG. 1 shows a usage state in which the manual feed tray 4 is opened and the user is in a tilted posture. On the other hand, when the manual feed tray 4 is not used, the manual feed tray 4 can be accommodated in the recess 7 formed on the side surface of the apparatus main body by rotating the manual feed tray 4 into an upright posture.

The manual feed tray 4 is one of the sheet supply devices 5 in the present invention. The manual feed tray 4 includes a sheet loading section 6 capable of loading a sheet bundle composed of at least one sheet such as printing paper when in use as shown in FIG. A space 8 into which the tip of the seat bundle loaded on the seat loading portion 6 can be inserted is formed under the recess 7 formed on the side surface of the apparatus main body. Therefore, the sheet bundle is loaded on the sheet loading unit 6 with the tip inserted into the space 8. Then, the manual feed tray 4 feeds the sheets one by one from the sheet bundle loaded on the sheet loading unit 6 and supplies the sheets to the image forming unit 2 inside the main body of the apparatus. The image forming unit 2 can form an image not only on the sheet fed from the paper feeding unit 3 but also on the sheet fed from the manual feed tray 4.

Further, the image forming apparatus 1 is provided with an image reading unit 10 and an automatic document conveying unit (ADF) 11 on the upper part of the apparatus main body. The image reading unit 10 optically reads an image of a document set by the user to generate image data. The automatic document transport unit 11 has a document tray 12, and automatically transports the document sheets set in the document tray 12 to the reading position of the image reading unit 10 one by one. The image scanning unit 10 is configured to perform a scanning operation synchronized with the document transporting operation by the automatic document transporting unit 11, and when the document sheet conveyed by the automatic document transporting unit 11 passes through a predetermined scanning position. Read the image of the original.

Further, the image forming apparatus 1 is provided with an operation panel 15 as a user interface on the front side of the apparatus main body. The operation panel 15 displays various operation screens that can be operated by the user, and receives job setting operations and job execution instructions by the user. For example, in the case of a copy job, the image forming apparatus 1 accepts a copy job setting operation by the user. At this time, the image forming apparatus 1 determines the tray to be fed from among the plurality of paper feed trays 3a, 3b, 3c, 3d and the manual feed tray 4 based on the setting operation by the user. Then, when the user instructs to start the execution of the copy job, the image reading unit 10 and the automatic document transporting unit 11 are driven to start the document reading operation, and the sheet bundle loaded on the tray designated by the user is loaded. The operation of feeding the sheets one by one is performed, and the copy job is executed.

FIG. 2 is a side view showing a configuration example of a sheet supply device 5 provided as a manual feed tray 4. Note that FIG. 2 illustrates a case where a sheet having low rigidity such as thin paper or plain paper is loaded on the sheet loading unit 6. The seat supply device 5 includes a seat loading unit 6, a pickup roller 30, a position detection sensor 38, a roller pair 40, and a handling member 50, and at least one sheet loaded on the upper surface of the sheet loading unit 6. One sheet on the uppermost surface is taken out from the sheet bundle 9 and fed to the transport path 45 on the downstream side in the transport direction. In FIG. 2, the sheet transporting direction is the left direction.

The seat loading portion 6 includes a seat rear end support portion 21 that is tilted from the side surface of the image forming apparatus 1, a seat tip supporting portion 22 provided inside the image forming apparatus 1, and an end portion of the seat tip supporting portion 22. It has a wall portion 23 for aligning the tips of the sheet bundles 9. For example, the seat tip support portion 22 is provided on the bottom surface of the space 8 into which the tip of the sheet bundle 9 is inserted. The wall portion 23 is erected at the end portion (tip) of the sheet tip support portion 22, and the tip of the sheet bundle 9 is abutted against the wall portion 23 so that the tip positions of the sheet bundle 9 are aligned.

The sheet tip support portion 22 is composed of, for example, a plate-shaped member arranged in a substantially horizontal direction, and supports the tip of the sheet bundle 9 in a substantially horizontal state. The seat rear end support portion 21 is configured as an inclined portion having a predetermined angle with respect to the seat tip support portion 22, and supports the rear end of the seat bundle 9. That is, the sheet rear end support portion 21 has a predetermined angle with respect to the substantially horizontal sheet tip support portion 22 in order to prevent the sheet from retracting due to the paper feeding operation when the sheet is continuously fed. It is a structure that supports the seat in a tilted position with the rear end side of the seat lifted. The seat rear end support portion 21 includes an auxiliary support portion 21a capable of extending a portion that supports the rear end of the seat bundle 9 when the seat size is large. For example, the auxiliary support portion 21a can be stored in the seat rear end support portion 21.

When a sheet having low rigidity such as thin paper is placed on the sheet loading portion 6, the lower surface of the sheet bundle 9 on the tip end side is supported by the sheet tip support portion 22 as shown in FIG. 2, and after the sheet bundle 9. The lower surface on the end side is supported by the seat rear end support portion 21. That is, the seat bundle 9 having low rigidity is in a state of being bent and loaded at the joint portion between the seat tip support portion 22 and the seat rear end support portion 21, and the tip portion of the seat bundle 9 is in a substantially horizontal state by the seat tip support portion 22. Supported by.

Further, the seat loading unit 6 can be raised and lowered with the seat bundle 9 loaded. For example, in the present embodiment, the seat tip support portion 22 that supports the tip end side of the seat bundle 9 can be moved up and down by the elevating drive portion 25 as indicated by the arrow Z1 in the figure. The elevating drive unit 25 can bring the upper surface of the sheet bundle 9 into contact with the surface of the pickup roller 30 by driving the seat tip support unit 22 ascending when the paper is fed from the seat loading unit 6. When the seat front end support portion 22 is raised, the seat loading portion 6 also raises the seat rear end support portion 21 integrally with the seat tip support portion 22. However, the present invention is not limited to this, and the seat tip support portion 22 may be configured to be separated from the seat rear end support portion 21 and to rise independently.

The pickup roller 30 is provided above the seat tip support portion 22. The pickup roller 30 is supported above the seat tip support portion 22 by a support member 31 that can swing around the rotation axis of the paper feed roller 41, which is one component of the roller pair 40, and is supported by an arrow in the figure. It can move up and down in the direction indicated by Z2. A position detection sensor 38 for detecting the position of the support member 31 in the Z2 direction is provided at a position near the support member 31. For example, the position detection sensor 38 is composed of an optical sensor having a light projecting unit and a light receiving unit, and detects the position of the support member 31 by detecting the amount of light received that changes according to the position of the support member 31. As the support member 31 swings in the direction of arrow Z2, the pickup roller 30 moves in the vertical direction integrally with the support member 31. Therefore, the position detection sensor 38 can be used as a sensor for detecting the height position of the pickup roller 30 in the vertical direction.

Further, the support member 31 is provided with an urging member 32 composed of a coil spring or the like. The urging member 32 is an urging means for pressing and urging the pickup roller 30 downward. For example, one end of the urging member 32 is connected to the support member 31, and the other end is connected to a wall surface fixed inside the image forming apparatus 1. Therefore, when the height position of the pickup roller 30 changes, the urging force of the urging member 32 also changes.

FIG. 3 is a side view showing one aspect of the sheet supply device 5 when paper feeding is performed by the pickup roller 30. Note that FIG. 3 illustrates a case where a sheet having low rigidity such as thin paper or plain paper is loaded on the sheet loading unit 6. As the seat tip support portion 22 rises, the pickup roller 30 comes into contact with the uppermost surface of the seat bundle 9 loaded on the seat loading portion 6, as shown in FIG. In that state, the pickup roller 30 is rotationally driven in a predetermined rotation direction R1 by a motor (not shown). An elastic member having irregularities is provided on the material or surface of the pickup roller 30. Therefore, when the pickup roller 30 rotates in the rotation direction R1 in a state of being in contact with the uppermost surface of the sheet bundle 9, at least one sheet at the upper part of the sheet bundle 9 can be sent out to the downstream side in the transport direction.

The roller pair 40 is provided on the downstream side of the pickup roller 30 in the transport direction in which the sheet is transported. The roller pair 40 includes a paper feed roller 41 and a separation roller 42, and separates the first sheet and the second and subsequent sheets when a plurality of sheets are sent out by the pickup roller 30. The first sheet is supplied to the transport path 45 on the downstream side in the transport direction, and the second and subsequent sheets are restricted from moving to the transport path 45 on the downstream side in the transport direction. The paper feed roller 41 is rotationally driven in a predetermined rotation direction R2 by a motor (not shown). The separation roller 42 is in contact with the surface of the paper feed roller 41, and as the paper feed roller 41 rotates in the rotation direction R2, the separation roller 42 is driven to rotate in the rotation direction R3. However, the separation roller 42 is provided with a torque limiter so that the separation roller 42 does not rotate in the rotation direction R3 unless the torque acting on the separation roller 42 becomes a predetermined torque or more.

For example, when one sheet is sent out toward the roller pair 40 by the pickup roller 30, the sheet is sandwiched between the nip portions of the roller pair 40. At this time, the paper feed roller 41 is in contact with the upper surface of the sheet, and the separation roller 42 is in contact with the lower surface of the same sheet. Then, as the paper feed roller 41 rotates in the rotation direction R2, the sheet is conveyed to the transfer path 45 on the downstream side of the roller pair 40. Along with this, a torque equal to or higher than a predetermined torque is applied to the separation roller 42, and the separation roller 42 is driven to rotate in the rotation direction R3 as the sheet moves.

On the other hand, when a plurality of sheets are sent out toward the roller pair 40 by the pickup roller 30, the plurality of sheets are sandwiched between the nip portions of the roller pair 40. At this time, the paper feed roller 41 contacts the upper surface of the first sheet located on the uppermost surface of the plurality of sheets, and the separation roller 42 contacts the lower surface side of the second and subsequent sheets. When the paper feed roller 41 rotates in the rotation direction R2 in that state, the first sheet is conveyed to the transfer path 45 on the downstream side in the transfer direction. At this time, since the first sheet slides on the upper surface of the second sheet and moves to the downstream side, the second and subsequent sheets do not move to the downstream side. Further, since a torque equal to or higher than a predetermined torque does not act on the separation roller 42, the separation roller 42 does not rotate. By such an action, the roller pair 40 separates the first sheet and the second and subsequent sheets, supplies the first sheet to the downstream side in the transport direction, and the second and subsequent sheets are supplied. Restrict movement to the downstream side in the transport direction.

The handling member 50 is arranged between the pickup roller 30 and the roller pair 40 in the sheet transport direction. The handling member 50 is a member that limits the number of sheets that come into contact with the tip of the sheet sent out from the pickup roller 30 and are conveyed to the roller pair 40 when a sheet having low rigidity such as thin paper or plain paper is fed. Is.

FIG. 4 is an enlarged view showing the pickup roller 30, the roller pair 40, and the handling member 50. As shown in FIG. 4, the handling member 50 is provided, for example, at the upper end of the wall portion 23 that aligns the tips of the sheet bundles 9. The handling member 50 includes a guide portion 51 having an inclined inclined surface whose height gradually increases from the upstream side to the downstream side in the transport direction in the sheet transport path between the pickup roller 30 and the roller pair 40. There is. The handling member 50 is configured such that the guide portion 51 limits the number of sheets transported toward the roller pair 40 when the pickup roller 30 feeds sheets having low rigidity such as thin paper or plain paper. Will be done. Such a handling member 50 may be integrally formed with the wall portion 23, or may be formed as a separate body from the wall portion 23 and attached to the upper end portion of the wall portion 23. Is also good. When the handling member 50 is formed as a separate body from the wall portion 23, the handling member 50 is formed of, for example, a metal plate or a PET (Polyethylene terephthalate) film.

When a sheet with low rigidity such as thin paper or plain paper is fed, the height position of the lowest point of the pickup roller 30 is held at a position lower than the upper end position 52 of the handling member 50 as shown in FIG. Will be done. For example, when the sheet feeding operation is started, the feeding roller 41 idles in the rotation direction R2. Along with this, the support member 31 is lowered by a certain amount, and the height position of the pickup roller 30 is also lowered. Further, the elevating drive unit 25 raises the seat tip support portion 22 and presses the upper surface of the seat bundle 9 against the pickup roller 30. At this time, the elevating drive unit 25 has a first position in which the height position of the lowest point of the pickup roller 30 is lower than the upper end position 52 of the handling member 50 based on the position of the support member 31 detected by the position detection sensor 38. When the position is reached, the ascent of the seat tip support portion 22 is stopped. As a result, the pickup roller 30 is in contact with the uppermost surface of the sheet bundle 9 at a position lower than the upper end position 52 of the handling member 50. At this time, the urging member 32 urges the pickup roller 30 downward with a constant pressing force to generate a constant frictional force between the pickup roller 30 and the sheet bundle 9. In this state, the pickup roller 30 is driven in the rotation direction R1, so that the sheet located at the upper part of the sheet bundle 9 is sent out to the downstream side in the transport direction.

When a large number of sheets are double-fed toward the downstream side by the pickup roller 30, the handling member 50 can press the tips of the large number of sheets against the inclined surface of the guide portion 51. As a result, when a large number of sheets try to move toward the downstream side, the large number of sheets receive a transfer resistance from the guide portion 51. By generating such a transfer resistance, as shown in FIG. 4, the handling member 50 guides only a few sheets on the upper layer among a large number of sheets sent out from the pickup roller 30. It is configured so that it can be transported to the downstream side by sliding along the inclined surface of 51. That is, with respect to the angle of the inclined surface of the guide portion 51, it is possible to move only a few sheets in the upper layer to the downstream side over the upper end position 52 of the guide portion 51, and many of them in the lower layer. The seat is pre-designed so that it cannot get over the upper end position 52 of the guide portion 51 due to the transport resistance.

Therefore, the handling member 50 comes into contact with the tip of the sheet sent out from the pickup roller 30 and is conveyed to the roller pair 40 when a sheet having low rigidity such as thin paper or plain paper is fed. It can be limited to about the number of sheets. This makes it possible to prevent a large number of sheets from being conveyed to the nip portion of the roller pair 40.

Next, FIG. 5 is a side view showing a sheet supply device 5 in a state where a sheet having high rigidity such as thick paper is loaded on the sheet loading unit 6. Here, the thick paper in the present embodiment refers to a sheet having a rigidity of a predetermined value or more, and when the pickup roller 30 is in the first position, normal paper feeding becomes difficult, and the thin paper and ordinary paper are used. It is a concept excluding paper. When a sheet having high rigidity such as cardboard is loaded, the tip of the sheet is placed on the sheet tip support portion 22 and the rear end of the sheet is placed on the sheet rear end support portion 21 as shown in FIG. The central portion of the seat is in a floating state from the seat loading portion 6. When the seat tip support portion 22 is raised in this state, the pickup roller 30 comes into contact with the upper surface of the seat floating from the seat loading portion 6, as shown in FIG. When the seat tip support portion 22 further rises from this state, the seat bends and deforms while pushing up the pickup roller 30 upward.

FIG. 7 is an enlarged view showing a state in which the height position of the pickup roller 30 reaches the first position for feeding a sheet having low rigidity such as thin paper. As shown in FIG. 7, when the pickup roller 30 is in the first position, the lowest point of the pickup roller 30 is located lower than the upper end position 52 of the handling member 50 on the downstream side. Further, a sheet having high rigidity such as thick paper is maintained in a state of being slightly lifted from the upper surface of the sheet tip support portion 22. When the pickup roller 30 rotates in the rotation direction R1 in the state shown in FIG. 7, the penetration angle of the sheet with respect to the guide portion 51 of the handling member 50 increases, and the transport resistance received by the sheet from the handling member 50 increases. As a result, the tip 9a of the sheet cannot advance toward the upper end position 52 of the guide portion 51 and stops, and the sheet cannot be conveyed toward the roller pair 40.

Therefore, the seat supply device 5 of the present embodiment is configured to change the height position of the pickup roller 30 according to the type of the seat loaded on the seat loading unit 6. For example, in the sheet supply device 5, when the sheet loaded on the sheet loading unit 6 is a sheet having low rigidity such as thin paper or plain paper, as shown in FIG. 4, the lowest point of the pickup roller 30 is reached. A first position whose height position is lower than the upper end position 52 of the handling member 50 is determined as the height position of the pickup roller 30. On the other hand, in the sheet supply device 5, when the sheet loaded on the sheet loading unit 6 is a sheet having high rigidity such as thick paper, the height position of the lowest point of the pickup roller 30 is set from the first position. Also determined to be in a higher second position. Then, the seat supply device 5 raises the seat tip support portion 22 so that the height position of the pickup roller 30 becomes the height position determined according to the type of the seat, and picks up at the height position suitable for the type of the seat. The roller 30 is driven to transport the sheet to the downstream side in the transport direction.

FIG. 8 is an enlarged view showing a pickup roller 30, a roller pair 40, and a handling member 50 for feeding a sheet having high rigidity such as thick paper. As shown in FIG. 8, when feeding a sheet having high rigidity, the sheet supply device 5 drives the elevating drive unit 25, and the sheet tip support unit 22 pushes up the pickup roller 30 to the maximum of the pickup roller 30. When the position of the lower point becomes the second position higher than the upper end position 52 of the handling member 50, the ascending of the seat tip support portion 22 is stopped. As a result, the pickup roller 30 is in contact with the uppermost surface of the sheet bundle 9 at a position higher than the upper end position 52 of the handling member 50. At this time, the amount of compression of the urging member 32 is larger than that when the pickup roller 30 is in the first position. Therefore, the urging force of the urging member 32 is larger than that when the pickup roller 30 is in the first position, and a highly rigid sheet can be pressed against the upper surface of the sheet tip support portion 22. Can be transformed into a posture substantially parallel to the transport direction. Further, by increasing the urging force of the urging member 32, it is possible to generate a constant frictional force between the pickup roller 30 and the sheet bundle 9, and the pickup roller 30 is rotated in the rotation direction R1. Allows the sheet to be normally transported toward the downstream side in the transport direction.

When the pickup roller 30 is held in the second position as described above, the sheet supply device 5 rotates the pickup roller 30 in the rotation direction R1 to feed the sheet to the downstream side in the transport direction. The sheet sent out to the downstream side by the rotation of the pickup roller 30 is sent out to the downstream side at a position higher than the upper end position 52 of the handling member 50. Therefore, the tip 9a of the sheet can easily get over the upper end position 52 of the handling member 50 and move to the downstream side. As a result, the seat supply device 5 can supply the tip 9a of the seat to the nip portion of the roller pair 40.

As described above, the seat supply device 5 of the present embodiment determines the height position of the pickup roller 30 when feeding the sheets according to the type of the sheet loaded on the sheet loading unit 6. When the seat tip support portion 22 is driven up and down, the seat tip support portion 22 is driven so that the height position of the pickup roller 30 is a height position determined according to the type of the seat. After that, the seat supply device 5 rotationally drives the pickup roller 30 to feed the seat toward the downstream side in the transport direction. Therefore, the sheet supply device 5 of the present embodiment supports a wide range of sheet types from thin paper to thick paper, and supplies sheets one by one to the transport path 45 regardless of the type of sheet used. Therefore, the paper feeding performance can be ensured regardless of the type of sheet.

Further, the urging member 32 that urges the pickup roller 30 can have a stronger urging force when the pickup roller 30 is in the second position than when the pickup roller 30 is in the first position. The pickup roller 30 can press the sheet against the sheet tip support portion 22 so that the central portion of a highly rigid sheet such as thick paper does not float when the 30 is in the second position. As a result, the tip of the sheet can be made substantially square with respect to the transport direction to reduce the plunge angle with respect to the handling member 50. Therefore, when the sheet is sent out by the pickup roller 30, even if the lower surface side of the sheet comes into contact with the guide portion 51 of the handling member 50, the sheet moves smoothly along the inclined surface of the guide portion 51, and the guide portion It can move downstream beyond the upper end position 52 of 51. Further, since the urging force of the urging member 32 becomes stronger, the frictional force generated between the pickup roller 30 and the sheet bundle 9 when the pickup roller 30 rotates can be increased. Therefore, the pickup roller 30 also has an advantage that the sheet can be reliably sent out to the downstream side.

FIG. 9 is a diagram showing an example of a change in the urging force of the urging member 32. For example, as shown in FIG. 9A, the urging member 32 generates an urging force F1 when the pickup roller 30 is in the first position P1, and the urging force 30 when the pickup roller 30 is in the second position P2. Anything that produces F2 will do. In this case, the urging member 32 is composed of, for example, coil springs having the same diameter in the axial direction.

Further, as shown in FIG. 9B, the urging member 32 does not generate an urging force when the pickup roller 30 is in the first position P1, and the urging member 32 does not generate an urging force when the pickup roller 30 is in the second position P2. It may generate an urging force F2. In this case, for example, one end of the urging member 32 can be separated from the support member 31, and when the pickup roller 30 is in the first position, the urging member 32 has a natural length, and the urging member 32 and the support member 31 The pickup roller 30 is in contact with the urging member 32 and the support member 31 while the pickup roller 30 is moving from the first position P1 to the second position P2. The urging member 32 contracts with the further rise of the urging member 32, and the urging force gradually increases. Then, when the pickup roller 30 moves to the second position P2, the urging member 32 may be configured to press the pickup roller 30 with the urging force F2.

Further, when it is necessary to increase the urging force F2 when the pickup roller 30 is in the second position P2, as shown in FIG. 9C, the urging member 32 in which the urging force increases non-linearly. May be adopted. In this case, for example, the urging force can be increased non-linearly by using a conical coil spring or the like as the urging member 32. Therefore, when the pickup roller 30 is moved to the second position P2 in order to feed a sheet having high rigidity such as thick paper, the urging member 32 may press the pickup roller 30 against the sheet bundle 9 with a large urging force F2. It is possible. As a result, it is possible to reduce the transfer failure caused by the pickup roller 30.

Next, a control mechanism for controlling the seat supply device 5 as described above will be described. FIG. 10 is a block diagram showing an example of the control mechanism of the image forming apparatus 1. The image forming apparatus 1 includes a control unit 60, a sheet conveying unit 71, and a communication interface 70 in addition to the image forming unit 2, the operation panel 15, the sheet loading unit 6, and the position detection sensor 38 described above.

The operation panel 15 includes a display unit 15a that is composed of a color liquid crystal display or the like and displays various operation screens that can be operated by the user, and an operation unit 15b that is composed of touch panel keys or the like and accepts operations by the user. ..

The sheet transport section 71 is for transporting the sheets loaded on the sheet load section 6 along the transport path 45, and includes a roller drive section 72 for rotationally driving the paper feed roller 41 and the pickup roller 30. ing. The roller drive unit 72 is composed of, for example, a motor.

The communication interface 70 is for communicating with other devices via a network such as a LAN (Local Area Network).

The control unit 60 controls the operation of each unit provided in the image forming apparatus 1. The control unit 60 includes a CPU 61 and a memory 62. The CPU 61 is a hardware processor that reads out and executes a program 63 stored in the memory 62. The memory 62 is a non-volatile storage means for storing the program 63. In addition to the program 63, various data and the like can be stored in the memory 62.

The CPU 61 of the control unit 60 functions as the job control unit 64 by executing the program 63. The job control unit 64 controls the execution of a job in the image forming apparatus 1. For example, the job control unit 64 displays a job setting screen on the display unit 15a of the operation panel 15 and accepts a job setting operation by the user. Then, the job control unit 64 sets the job based on the setting operation by the user.

Further, the job control unit 64 can receive a print job transmitted from another device via the communication interface 70 and control the execution of the print job. Information related to job settings is added to the print job, and the job control unit 64 sets the print job based on the information.

Further, when the sheet bundle 9 is loaded on each of the plurality of paper feed trays 3a, 3b, 3c, 3d and the manual feed tray 4, the job control unit 64 inputs the sheet type to the display unit 15a. Displays the operation screen and accepts the user's operation to specify the sheet type. Then, the job control unit 64 stores in the memory 62 the types of sheets loaded in each of the plurality of paper feed trays 3a, 3b, 3c, 3d and the manual feed tray 4.

When the user instructs to start executing the job, or when the print job is received, the job control unit 64 starts executing the job. For example, when the manual feed tray 4 (sheet supply device 5) is specified as the tray for feeding sheets in the job settings, the job control unit 64 includes the sheet loading unit 6, the sheet transport unit 71, and the image forming unit. 2 is operated and the execution of the job specified by the user is controlled. At this time, the job control unit 64 functions as a seat type determination unit 65 and a position adjustment unit 66.

The sheet type determination unit 65 determines the type of sheet loaded on the manual feed tray 4 designated as the paper feed target. That is, the sheet type determining unit 65 reads information about the type of the sheet loaded on the manual feed tray 4 from the memory 62, and determines the type of the sheet based on the information. As a result, the job control unit 64 can specify whether the sheet fed from the manual feed tray 4 is thin paper, plain paper, or thick paper when the execution of the job is started.

The position adjusting unit 66 determines the height position of the pickup roller 30 based on the discrimination result by the seat type discriminating unit 65, and drives the elevating drive unit 25. That is, the position adjusting unit 66 determines the height position of the pickup roller 30 at a position suitable for the type of sheet fed from the manual feed tray 4, and the position of the lowest point of the pickup roller 30 is the determined position. The elevating drive unit 25 is driven so as to be. For example, when the sheet fed from the manual feed tray 4 is a sheet having low rigidity such as thin paper or plain paper, the lowest point of the pickup roller 30 of the position adjusting unit 66 is lower than the upper end position 52 of the handling member 50. The height of the lowest point of the pickup roller 30 is determined by driving the elevating drive unit 25 while detecting the height position of the pickup roller 30 based on the output from the position detection sensor 38. Adjust so that the position is the first position. Further, when the sheet fed from the manual feed tray 4 is a sheet having high rigidity such as thick paper, the position adjusting portion 66 has a second position in which the lowest point of the pickup roller 30 is higher than the upper end position 52 of the handling member 50. By driving the elevating drive unit 25 while determining the position of the pickup roller 30 and detecting the height position of the pickup roller 30 based on the output from the position detection sensor 38, the height position of the lowest point of the pickup roller 30 can be set. Adjust so that it is in the second position.

When the height position of the pickup roller 30 is adjusted to the height position according to the type of the seat as described above, the job control unit 64 drives the seat transport unit 71 and is loaded on the seat loading unit 6. Starts feeding operation of the existing sheet.

Next, the processing procedure performed by the control unit 60 will be described. FIG. 11 is a flowchart showing an example of a processing procedure for controlling the operation of the sheet supply device 5. When the control unit 60 detects that the seat is placed on the seat loading unit 6 (step S1), the control unit 60 determines the type of the seat (step S2). At this time, the control unit 60 displays an operation screen for inputting the sheet type on the display unit 15a of the operation panel 15, and accepts the user to specify the sheet type.

FIG. 12 is a diagram showing an example of an operation screen displayed on the display unit 15a of the operation panel 15. On the operation screen G1 shown in FIG. 12A, button images B1 and B2 in which the user selects either thin paper, plain paper, or thick paper are displayed. Therefore, when the user places thin paper or plain paper on the sheet loading unit 6, the thin paper or plain paper can be set as the type of the sheet by touching the button image B1. Further, when the user places the thick paper on the sheet loading unit 6, the thick paper can be set as the type of the sheet by touching the button image B2.

Further, the display unit 15a may display the operation screen G2 shown in FIG. 12B. The operation screen G2 is a screen for urging the user to input the rigidity of the sheet, and an input field B3 for inputting the rigidity of the sheet numerically is displayed in the center of the screen. Therefore, the user can set the type of the sheet by inputting the rigidity of the sheet in the input field B3.

Further, the display unit 15a may display the operation screen G3 shown in FIG. 12 (c). The operation screen G3 is a screen for urging the user to input the basis weight of the sheet, and an input field B4 for numerically inputting the basis weight of the sheet is displayed in the center of the screen. Therefore, the user can set the type of the sheet by inputting the basis weight of the sheet in the input field B4. The basis weight of the sheet is a value indicating the weight of the sheet per unit area, and is a value that correlates with the rigidity of the sheet.

The control unit 60 determines the type of sheet based on the user's operation on the operation screens G1, G2, and G3 as described above, and the sheet loaded on the sheet loading unit 6 is either thin paper, plain paper, or thick paper. Identify if there is. For example, when the user inputs the rigidity of the sheet, the control unit 60 determines that the paper is thick when the rigidity of the sheet is equal to or more than a predetermined value, and thin paper or plain paper when the rigidity of the sheet is less than the predetermined value. Is determined to be. Further, when the user inputs the basis weight of the sheet, the control unit 60 determines that the paper is thick when the basis weight of the sheet is equal to or more than a predetermined value, and thin paper when the basis weight of the sheet is less than the predetermined value. Or, it is determined that the paper is plain paper.

Returning to the flowchart of FIG. 11, when the control unit 60 determines that the sheet loaded on the sheet loading unit 6 is thin paper or plain paper (YES in step S3), the pickup roller 30 for feeding the sheet is fed. The height position of the member 50 is determined to be a first position lower than the upper end position 52 of the handling member 50 (step S4). On the other hand, when it is determined that the sheet loaded on the sheet loading unit 6 is thick paper (NO in step S3), the control unit 60 handles the height position of the pickup roller 30 when feeding the sheet. It is determined to be a second position higher than the upper end position 52 of the member 50 (step S5).

Subsequently, when the control unit 60 detects the job execution start instruction (step S6), the control unit 60 drives the elevating drive unit 25 and starts ascending the seat tip support unit 22 (step S7). Then, the control unit 60 determines whether or not the height position of the pickup roller 30 has reached the height position determined in step S4 or S5 based on the output from the position detection sensor 38 (step S8), and still reaches. If not (NO in step S8), the seat tip support portion 22 continues to rise. When the height position of the pickup roller 30 reaches the height position determined in step S4 or S5 (YES in step S8), the control unit 60 stops the drive of the elevating drive unit 25, and the pickup roller 30 is moved to step S4. Alternatively, it is held at the height position determined in S5 (step S9). Then, the control unit 60 starts the paper feeding operation of the sheet loaded on the sheet loading unit 6 by driving the sheet transport unit 71 (step S10).

At this time, if the sheet fed from the sheet loading unit 6 is thick paper, the lowest point of the pickup roller 30 is higher than the upper end position 52 of the handling member 50. Therefore, the sheet smoothly exceeds the upper end position 52 of the handling member 50 and is conveyed to the roller pair 40 on the downstream side.

If the sheet fed from the sheet loading unit 6 is thin paper or plain paper, the lowest point of the pickup roller 30 is lower than the upper end position 52 of the handling member 50. Therefore, when a large number of sheets are sent out to the downstream side by the pickup roller 30, the guide portion 51 of the handling member 50 can limit the number of sheets to be conveyed to the roller pair 40. As a result, it becomes possible to normally separate the first sheet located on the uppermost surface of the roller pair 40 from the second and subsequent sheets, and only the first sheet is transported to the transport path 45 on the downstream side. can do.

As described above, the seat supply device 5 of the present embodiment comes into contact with the seat loading unit 6 that can move up and down with the seat bundle 9 loaded, and the uppermost surface of the seat bundle 9, and moves up and down the seat loading unit 6. A pickup roller 30 that can move up and down along with the sheet bundle 9 to be fed downstream in the transport direction, and a pickup roller 30 installed on the downstream side of the pickup roller 30 in the transport direction, when a plurality of sheets are fed by the pickup roller 30. A roller pair 40 that separates the first sheet and the second and subsequent sheets, supplies the first sheet to the downstream side in the transport direction, and regulates the movement of the second and subsequent sheets, and a pickup. It is provided between the roller 30 and the roller pair 40, and includes a handling member 50 that comes into contact with the tip of the sheet sent out from the pickup roller 30 and limits the number of sheets transported to the roller pair 40. Then, the seat supply device 5 determines the height position of the pickup roller 30 according to the type of the seat loaded on the seat loading unit 6, and drives the seat loading unit 6 up and down so as to reach the determined height position. .. As a result, when feeding the sheets loaded on the sheet loading unit 6, it is possible to feed the sheets in a state where the height position of the pickup roller 30 is adjusted to a position suitable for the type of the sheet. be. Therefore, the sheet supply device 5 supports a wide range of sheet types from thin paper to thick paper, and can normally feed paper regardless of the type of sheet used. Regardless of this, paper feed performance can be ensured.

Further, the sheet supply device 5 determines the height position of the pickup roller 30 to be higher than that of thin paper or plain paper when the sheet loaded on the sheet loading unit 6 is thick paper. Therefore, when the sheet is thick paper, it is possible to solve the problem that the sheet is not conveyed to the downstream side of the handling member 50.

Further, the seat supply device 5 includes an urging member 32 that urges the pickup roller 30 toward the seat bundle 9 loaded on the seat loading unit 6. Due to the urging force of the urging member 32, a constant frictional force is generated between the pickup roller 30 and the seat when the pickup roller 30 sends the seat to the downstream side in the transport direction. It is possible to reliably send out to the downstream side in the transport direction.

Further, the urging member 32 is provided so that the urging force when the pickup roller 30 is in the second position is stronger than the urging force when the pickup roller 30 is in the first position. .. Therefore, when the sheet is thick paper, the frictional force between the pickup roller 30 and the sheet is high, so that the thick paper can be reliably sent out to the downstream side in the transport direction.

In particular, when the seat supply device 5 is provided as the manual feed tray 4 as in the present embodiment, the seat loading portion 6 has an inclined surface whose height position increases from the front end position to the rear end position of the seat. When a sheet with high rigidity such as thick paper is placed, the central part of the sheet is in a floating state. Even in such a state, if the pickup roller 30 rises to the second position, the urging force of the urging member 32 becomes stronger, so that the central portion of the seat can be pressed against the bottom surface of the seat loading portion 6. Therefore, a constant frictional force can be obtained between the pickup roller 30 and the seat. Therefore, the urging force of the urging member 32 is stronger when the pickup roller 30 is in the second position than when it is in the first position, so that a frictional force required for transporting the sheet is generated. It has the advantage of being able to.

The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the contents described in each of the above embodiments, and various modifications can be applied.

For example, in the above embodiment, the case where the image forming apparatus 1 is configured as an MFP is illustrated. However, the image forming apparatus 1 is not limited to the one configured as an MFP. That is, the image forming apparatus 1 may be a printer having only a printing function.

Further, in the above embodiment, the case where the manual feed tray 4 is the sheet supply device 5 is exemplified. However, the tray that can adopt the above-described configuration as the sheet supply device 5 is not limited to the manual feed tray 4. For example, the configuration of the sheet supply device 5 described above may be adopted for a plurality of paper feed trays 3a, 3b, 3c, 3d incorporated in the main body of the image forming device 1. Further, the above-described configuration of the sheet supply device 5 can also be applied to the document tray 12 mounted on the automatic document transfer unit 11.

Further, in the above embodiment, the user inputs the type of the sheet loaded on the sheet loading unit 6, and the control unit 60 determines the type of the sheet based on the information input by the user. However, the present invention is not limited to this, and a configuration in which the type of the sheet is automatically detected by using a light reflection type sensor, a light transmission type sensor, or the like may be adopted. For example, when a light reflection type sensor is used, the light reflection type sensor is arranged above the sheet loading unit 6, and the upper surface of the sheet bundle 9 is irradiated with light to detect the reflected light from the upper surface of the sheet bundle 9. .. As a result, it is possible to detect the amount of attenuated light based on the thickness of the sheet, and it is possible to detect the basis weight based on the thickness of the sheet. Therefore, it is possible to determine the type of sheet from the detected result of the reflected light.

Further, in the above embodiment, in order to detect the height position of the pickup roller 30, an example of providing a position detection sensor 38 to detect the position of the support member 31 has been described. The position detection sensor 38 is turned on when the pickup roller 30 is in the first position, and is turned off when the pickup roller 30 is separated from the first position. The first sensor and the pickup roller 30 are second. It may be configured by combining two sensors with a second sensor that turns on when the pickup roller 30 is in the position and turns off when the pickup roller 30 moves away from the second position. Further, the position detection sensor 38 is not necessarily limited to detecting the position of the support member 31. For example, the position detection sensor 38 may be arranged so that the position of the pickup roller 30 can be directly detected.

Further, in the above embodiment, when the sheet loaded on the sheet loading unit 6 is thick paper, the second position determined as the height position of the pickup roller 30 is higher than the upper end position 52 of the guide unit 51. The case of the position is illustrated. However, the second position is not necessarily limited to a position higher than the upper end position 52 of the guide portion 51. For example, the second position may be a height position near the upper end position 52 of the guide portion 51. That is, the second position may be at the same height as the upper end position 52 of the guide portion 51, or may be a position slightly lower than the upper end position 52 of the guide portion 51.

Further, in the above embodiment, two types of sheet, thin paper, plain paper and thick paper, are exemplified, but the type of sheet discriminated by the control unit 60 is not limited to two types. For example, when the sheet is thick paper, the control unit 60 determines the type of thick paper according to the basis weight and rigidity of the thick paper, and the height position of the pickup roller 30 (second) based on the type of thick paper. The position of) may be determined. In this case, it is preferable that the control unit 60 determines the second position to a higher position as the basis weight and rigidity of the thick paper become higher.

1 Image forming device 4 Manual feed tray 5 Seat supply device 6 Seat loading unit 30 Pickup roller 32 Biasing member (Bending means)
40 Roller vs. 41 Paper Feed Roller 42 Separation Roller 50 Handling Member 51 Guide Unit 60 Control Unit (Control Means)

Claims (11)

A seat loading section that can be moved up and down with a bundle of seats loaded,
A pickup roller that comes into contact with the uppermost surface of the sheet bundle and can move up and down as the sheet loading portion moves up and down, and sends out the sheet of the sheet bundle to the downstream side in the transport direction.
It is installed on the downstream side in the transport direction of the pickup roller, and when a plurality of sheets are sent out by the pickup roller, the first sheet and the second and subsequent sheets are separated and the first sheet is transported. A pair of rollers that supply to the downstream side in the direction and regulate the movement of the second and subsequent sheets,
A handling member arranged between the pickup roller and the roller pair, which comes into contact with the tip of the sheet delivered from the pickup roller and limits the number of sheets transported to the roller pair.
A control means that determines the height position of the pickup roller according to the type of the seat loaded on the seat loading unit and raises and lowers the seat loading unit so as to reach the height position.
A seat feeder characterized by being equipped with. The sheet supply device according to claim 1, wherein the control means determines the type of the sheet based on the rigidity or the basis weight of the sheet. The control means is characterized in that when the sheet loaded on the sheet loading unit is thick paper, the height position of the pickup roller is determined to be higher than that of thin paper or plain paper. Or the sheet supply device according to 2. An urging means for urging the pickup roller toward the bundle of seats loaded on the seat loading unit.
The sheet supply device according to any one of claims 1 to 3, further comprising. The handling member has an inclined guide portion whose height gradually increases from the upstream side to the downstream side in the sheet transport path between the pickup roller and the roller pair.
When the sheet loaded on the sheet loading section is thin paper or plain paper, the control means determines the height position of the pickup roller to a first position lower than the upper end position of the guide section. When the sheet loaded on the sheet loading portion is thick paper, the height position of the pickup roller is determined to be a position higher than the first position and a second position near the upper end position of the guide portion. The sheet supply device according to any one of claims 1 to 3. An urging means for urging the pickup roller toward the bundle of seats loaded on the seat loading unit.
Further prepare
The urging means is characterized in that the urging force when the pickup roller is in the second position is stronger than the urging force when the pickup roller is in the first position. Item 5. The sheet supply device according to item 5. The urging means is characterized in that the pickup roller is not urged when the pickup roller is in the first position, and the pickup roller is urged when the pickup roller is in the second position. The sheet supply device according to claim 6. The sheet supply device according to claim 4, 6 or 7, wherein the urging means increases the urging force in a non-linear manner as the height position of the pickup roller increases. The seat supply device according to claim 4, 6, 7 or 8, wherein the urging means is composed of a coil spring. The seat supply device according to any one of claims 1 to 9, wherein the seat loading portion has an inclined surface whose height position increases from the front end position to the rear end position of the seat. An image forming apparatus comprising the sheet feeding apparatus according to any one of claims 1 to 10.

Images