Medium feeder and image forming apparatus

Abstract

To improve the accuracy of position regulation by a medium position regulating member with a plurality of mediums stacked and received inhibited from adhering closely to one another.SOLUTION: A medium feeder comprises a medium receiving part to receive a stack of sheet-like mediums so as to individually separate and feed the medium from the medium receiving part. The medium receiving part can be pulled out to slide relative to a device housing and comprises a bottom plate on which the medium is rested, a medium-position regulating member that is opposed to an end in a widthwise direction of the mediums stacked and regulates the position of the medium, and a medium-end moving member that moves a vicinity of an end in a width direction of the medium rested on the bottom plate to a position pushed up higher than the bottom plate when the medium receiving part is pulled out of the device housing, and that is spaced from the vicinity of the end in the width direction of the mediums when the medium receiving part is accommodated in the device housing.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a medium supply device and an image forming apparatus. [Background technology]

[0002] A media feeder is known that sequentially removes the topmost sheet of media from a stack and transports it downstream. Such a media feeder is often installed in an image forming apparatus that forms images on the media, and also provides the function of feeding media to the image forming unit. When the media feeder is integrated with the image forming apparatus, the media feeder is often installed at the bottom of the image forming apparatus.

[0003] It is necessary to prevent skew or horizontal misalignment from occurring in the orientation of the media from when it is supplied from the media supply device until it is transported to the destination position. The media supply device is equipped with a position regulation member in the storage section that stores the media, which regulates the storage position and orientation of the media to ensure that the orientation of the media is correct in the media transport direction. The media position regulation member regulates the orientation of the media in the transport direction and the position in the direction perpendicular to the transport direction (media width direction).

[0004] Generally, taking into consideration factors such as work efficiency when storing media in the storage section, the width of the storage space formed by the media position restricting member is set slightly larger than the width of the media, and is configured to narrow the gap so that it contacts the widthwise edge of the media after the media is stored. However, since the width dimension of the media is determined by cutting performed during the media manufacturing process, dimensional variations can occur. Furthermore, the position of the widthwise edge of the media can also vary among multiple loaded media.

[0005] Therefore, when media are placed in the storage section, not all edges of the stacked media are often in contact with the media positioning member. In other words, due to variations in media width, a stack of media with a smaller width than the other media will have a gap between it and the media positioning member. This gap makes the smaller media more susceptible to lateral registration misalignment and skew.

[0006] Furthermore, media that are relatively wider than other media are accommodated in a state where they rub against the media position restricting member, which increases the resistance when they move in the transport direction and can easily cause transport problems.

[0007] Ideally, the set position of the media position regulating member in the storage section should match the width dimension of the media, so a configuration is known in which the side fence (media position regulating member) is in close contact with the end face of the sheet stack (the end in the width direction of the media) (see, for example, Patent Document 1). Summary of the Invention [Problem to be solved by the invention]

[0008] In the configuration disclosed in Patent Document 1, when the edges of a stack of media are unevenly positioned in the stacking direction due to variations in the width direction of the media, or when the media are stuck together due to static electricity, etc., the edges of the media cannot be aligned by the media position restricting member. As a result, some of the media end up with a gap between them and the media position restricting member, which can cause registration misalignment during transport (supply) or reduced transport accuracy due to skew.

[0009] An object of the present invention is to provide a medium supplying device that prevents a plurality of stacked and accommodated media from coming into close contact with each other and improves the position regulation accuracy of a medium position regulation member. [Means for solving the problem]

[0010] In order to solve the above problems, one aspect of the present invention is a media supply device that has a media storage section that stores sheet-like media in a stacked state, and that separates and supplies the media individually from the media storage section, wherein the media storage section can be moved to be withdrawn by sliding it relative to the device housing, and is characterized by having a bottom plate on which the media is placed, a media position regulating member that faces the widthwise end of the loaded media and regulates the position of the media, and a media end moving member that moves the vicinity of the widthwise end of the media placed on the bottom plate to a position higher than the bottom plate when the media storage section is withdrawn from the device housing, and moves away from the vicinity of the widthwise end of the media when the media storage section is stored in the device housing. [Effects of the Invention]

[0011] According to the present invention, it is possible to prevent a plurality of media stored in a stack from coming into close contact with each other, thereby improving the position regulation accuracy of the media position regulation member. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram showing the overall configuration of an image forming apparatus. [Figure 2] FIG. 2 is a plan view of a sheet tray provided in the medium supply device. [Figure 3] FIG. 2 is a front view of a sheet tray provided in the medium supply device. [Figure 4] FIG. 2 is a diagram illustrating the configuration of a control block included in the medium supply device. [Figure 5] 10A and 10B are diagrams illustrating problems with a medium supply device according to a conventional example. [Figure 6] 5A to 5C are diagrams illustrating the operation of a sheet tray provided in the medium supply device according to the present invention. [Figure 7] 5A to 5C are diagrams illustrating the operation of a sheet tray provided in the medium supply device according to the present invention. [Figure 8] 10A to 10C are diagrams illustrating the effects of the medium supply device according to the present invention. [Figure 9] 2A and 2B are diagrams illustrating the configuration of a sheet tray provided in the medium supply device according to the present invention. [Figure 10]2A and 2B are diagrams illustrating the configuration of a sheet tray provided in the medium supply device according to the present invention. [Figure 11] 10A to 10C are diagrams illustrating another operation of the sheet tray included in the medium supply device according to the present invention. [Figure 12] 10A and 10B are diagrams illustrating another configuration of the sheet tray included in the medium supply device according to the present invention. [Figure 13] 10A to 10C are diagrams illustrating another operation of the sheet tray included in the medium supply device according to the present invention. [Figure 14] 10A and 10B are diagrams illustrating another configuration of the sheet tray included in the medium supply device according to the present invention. [Figure 15] 10A and 10B are diagrams illustrating another configuration of the sheet tray included in the medium supply device according to the present invention. [Figure 16] 5 is a flowchart showing an example of the operation of the medium supply device according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0013] A medium supply device and an image forming apparatus according to the present invention will be described below with reference to the drawings. Fig. 1 is a diagram showing the overall configuration of an MFP1 as an embodiment of an image forming apparatus. The MFP1 has a function of forming an image on paper P, which is an example of a sheet-like medium. As shown in Fig. 1, the MFP1 has an image forming unit 10 and a sheet tray unit 100.

[0014] The sheet tray unit 100 corresponds to an embodiment of a medium supply device according to the present invention.

[0015] As will be described later, the sheet tray unit 100 can improve operability when refilling paper P, which is a sheet-like medium, and can improve transport (supply) accuracy by improving the positional control accuracy of paper P.

[0016] The image forming unit 10 forms an image on a sheet P and discharges the sheet P with the image formed on it. The sheet P is supplied to the image forming unit 10 from a sheet tray unit 100, which serves as a medium supply unit. The sheet tray unit 100 stacks and stores the sheets P, and separates and supplies each sheet P to the image forming unit 10. The sheet tray unit 100 includes a conveying unit 11 that separates the sheets P from the stack storage space and conveys them downstream in the conveying direction (see FIG. 3).

[0017] The conveying unit 11 may be provided in the image forming unit 10.

[0018] The conveying unit 11 separates and conveys the individual sheets of paper P from the storage space. The sheets of paper P are then conveyed to the image forming unit 10, where an image is formed on the sheets of paper P and the sheets are discharged. There are several well-known methods for performing image formation processing in the image forming unit 10, such as an inkjet method that forms an image using ink and an electrophotographic method that forms an image using toner. The medium supply device according to the present invention is applicable to any of these image forming methods. Note that the configuration of the image forming unit 10 is already well-known, so a detailed description thereof will be omitted.

[0019] The sheet tray unit 100 is provided with a plurality of sheet trays 110, each divided into individual stages. The sheet tray unit 100 is provided with a plurality of sheet tray units 100, which form a storage space for stacking and storing paper sheets P. Each sheet tray 110 is configured to be able to separately store different sizes of paper sheets P. Note that the features of the sheet tray unit 100 described below are the same regardless of the size of the paper sheets P stored therein.

[0020] Next, the basic structure of the sheet tray unit 100 as a medium storage section will be described with reference to Figures 2 and 3. The characteristic configuration of the present invention will be described later.

[0021] Fig. 2 is a plan view of the sheet tray 110 included in the sheet tray unit 100. Fig. 3 is a front view of the sheet tray 110. For ease of explanation, the Y axis is coaxial with the supply direction of the paper P, and the direction indicated by the arrow R in the drawing corresponds to the supply direction of the paper P (so-called conveyance direction).

[0022] The X axis is coaxial with the pull-out direction of the sheet tray 110. The direction indicated by the arrow S in the drawing is the pull-out direction, which is the direction in which the sheet tray 110 can slide. Therefore, the direction opposite to the arrow S corresponds to the retraction direction of the sheet tray 110.

[0023] The sheet tray 110 includes a bottom plate 160 as a plate-like member on which the paper sheets P are placed. A portion of the bottom plate 160 is biased upward (in the Z direction) by an elastic member 130 as a bottom plate biasing member (see FIG. 3). That is, the paper sheets P are stored with their leading edge in the supply direction biased toward the conveying section 11.

[0024] When the stacked sheets P are fed in the transport direction (the direction of arrow R in FIG. 2) and the amount of sheets stacked on the bottom plate 160 decreases, the load from the sheets P on the bottom plate 160 decreases. At this time, the bottom plate 160 is configured so that the angle that the bottom plate 160 forms with respect to the horizontal increases due to the biasing force of the bottom plate 160. As a result, the top of the stacked sheets P reaches a predetermined position (feed start position) regardless of the remaining amount of sheets stacked. This feed start position corresponds to a position where the sheets P can come into contact with the sheet feed roller 12 provided in the transport unit 11.

[0025] A pair of side fences 120 serving as medium position regulating members are disposed opposite each other on both sides of the width direction of the paper P. Here, the width direction of the paper P refers to the direction intersecting (perpendicular to) the transport direction of the paper P (the direction of arrow R in FIG. 2, which corresponds to the supply direction of the paper P) and parallel to the surface of the paper P. In other words, the dimension perpendicular to the transport direction of the paper P corresponds to the width dimension of the paper P. In the following description, the width direction edge of the paper P may be referred to as the "width direction edge." The side fences 120 are members for aligning the positions of the width direction edges of the paper P stacked on the bottom plate 160. In other words, the side fences 120 are disposed to clamp the paper P so that the position of the width direction edge of the stacked paper P in the paper P and the orientation of the paper P relative to the transport direction are maintained normal as the paper P is transported to the image forming unit 10.

[0026] The side fences 120 are configured to perform a regulating operation in which, when the sheet tray 110 is returned to the device housing with multiple sheets of paper P placed on the bottom plate 160, the opposing side fences 120 move in a direction narrowing the gap between them and come into contact in the conveyance direction of the sheets of paper P. At this time, the opposing side fences 120 operate to push in the widthwise ends of the sheets of paper P. This regulating operation may be performed by repeatedly making contact and separating from the widthwise ends of the sheets of paper P in short increments. This regulating operation regulates the position of the widthwise ends of the sheets of paper P, allowing the ends to be aligned.

[0027] The sheet tray unit 100 also includes a drive section 140 as a drive source for the regulating operation of the side fences 120, a conveying section 11 that separates and conveys the paper P, and a control section 150 that controls the operations of each.

[0028] 3, a transport unit 11 that transports the paper P to the image forming unit 10 is provided near the end of the sheet tray 110 in the feeding direction of the paper P. The transport unit 11 includes a paper feed roller 12 that removes the topmost paper P stacked on the sheet tray 110 and moves it downstream. In order for the paper feed roller 12 to move the topmost paper P in the feeding direction, it is important that the stacked paper P, especially the topmost paper P, are separated one by one.

[0029] [Control configuration of media supply device] The configuration of the control unit 150 will be described with reference to Fig. 4. As shown in Fig. 4, the control unit 150 has the same configuration as an information processing terminal such as a general server or a PC (Personal Computer).

[0030] The control unit 150 has a CPU (Central Processing Unit) 151, a RAM (Random Access Memory) 152, a ROM (Read Only Memory) 153, a storage unit 154, and an I / F (Interface) 155, which are connected via a bus 156. The CPU 151 is a calculation means and controls the operation of the entire medium supply device.

[0031] The RAM 152 is a volatile storage medium that can read and write information at high speed. When the CPU 151 processes information, the RAM 152 is used as a work area for the CPU 151.

[0032] The ROM 153 is a read-only nonvolatile storage medium, and stores programs such as firmware.

[0033] The storage unit 154 is a non-volatile storage medium that can read and write information, and stores an OS (Operating System), various control programs, application programs, etc. The storage unit 154 is, for example, a solid state drive (SSD) or a hard disk drive (HDD).

[0034] The I / F 155 connects and controls the bus with various hardware, networks, etc. The drive unit 140 is connected to the control unit 150 via the I / F 155. The operation of the drive unit 140 is controlled based on a control program executed using the arithmetic processing function of the CPU 151. The drive unit 140 controls, for example, the rotation and rotation direction of a side fence movement motor 1251, which will be described later.

[0035] When the sheet tray 110 is in a state where it is possible to supply the sheet P, the control unit 150 calculates the width dimension of the sheet P based on a detection signal from the width detection sensor 180, which serves as a medium dimension detection unit that detects the width dimension of the sheet P placed on the bottom plate 160.

[0036] [Issues with conventional examples] Here, a problem with a conventional example when regulating the widthwise position of the paper P using side fences 120 as in the sheet tray unit 100 will be described with reference to Fig. 5. Fig. 5 is a view of the sheet tray 110 as seen from the opposite side to the conveyance direction.

[0037] As shown in FIG. 5, assume that side fences 120 are used to regulate and align the widthwise edge positions of a stack of sheets P placed on bottom plate 160. In this case, a certain number of sheets P may form clumps due to static adhesion force Ap, causing the widthwise edge faces to become stepped. In this state, even if side fences 120 are pressed against the widthwise edge faces of sheets P, the side fences 120 can only contact the edges of the block of sheets P, leaving gaps Gp, and the sheets P are not positioned correctly. Therefore, the sheets are stored in sheet tray 110 in a state where each block is prone to horizontal registration misalignment and skew.

[0038] As described above, the present invention is characterized in that the storage state of the paper P is changed before the regulating operation by the side fence 120 is performed so that the stored paper P does not become in a state that hinders the alignment of the position of the widthwise end.

[0039] [First embodiment] Next, a first embodiment of the sheet tray unit 100 will be described with reference to Figures 6 to 8. The sheet tray unit 100 according to this embodiment includes a medium end moving member 170 in addition to side fences 120 that regulate the position of the paper P in the width direction.

[0040] The medium end moving member 170 is a member that pushes up and supports the width direction end of the paper sheets P placed on the bottom plate 160. When the sheet tray 110 is drawn out from the device housing, the medium end moving member 170 moves the vicinity of the width direction end of the paper sheets P placed on the bottom plate 160 relatively in a direction away from the bottom plate 160. In other words, when the sheet tray 110 is drawn out, the medium end moving member 170 supports the vicinity of the width direction end of the plurality of paper sheets P placed on the bottom plate 160 at a position that is pushed up higher than the position of the bottom plate 160.

[0041] 6, when the sheet tray 110 is pulled out from the sheet tray unit 100 (device housing), that is, when the sheet tray 110 is ready to be replenished with paper P, the medium end moving member 170 has a protruding member 171 that protrudes above the bottom plate 160. The protruding member 171 is configured to either protrude above the bottom plate 160 (protruding state) or retract below the bottom plate 160 (retracted state) by a link member 172 that is disposed below the bottom of the sheet tray 110 moving relative to the sheet tray 110.

[0042] The link member 172 is a rod-shaped member that is elongated in the direction in which the sheet tray 110 can be pulled out (the direction of the arrow S). The link member 172 has an uneven portion formed on the surface that faces the sheet tray 110, i.e., the surface that the protruding member 171 abuts against. When the protruding member 171 abuts against the recessed portion 172a, the protruding member 171 is in a retracted state. When the protruding member 171 abuts against the convex portion 172b, the protruding member 171 is in a protruding state.

[0043] 6 illustrates a state in which the sheet tray 110 is pulled out from the device housing. That is, it illustrates a state in which paper sheets P are being replenished into the sheet tray 110. When the sheet tray 110 is in the replenishment position, the protruding member 171 is in a protruding state in which it abuts against the convex portion 172b. In this protruding state, the tip portion of the protruding member 171 is positioned above the bottom plate 160. The protruding members 171 are arranged at positions spaced apart in the width direction of the paper sheets P, and multiple protruding members 171 are arranged at positions corresponding to the widthwise ends of the paper sheets P. When these protruding members 171 are in a protruding state, they come into contact with the vicinity of the widthwise ends of the paper sheets P, so that the paper sheets P are lifted up from below by the protruding members 171.

[0044] 6, when the protruding members 171 are in the protruding state, the paper P is supported above the bottom plate 160 near the widthwise ends, and the central portion of the paper P in the widthwise direction hangs down below the widthwise ends and is supported by the bottom plate 160. In other words, part of the paper P is in contact with the bottom plate 160, and another part is in contact with and supported by the protruding members 171. In this state, the paper P forms a beam-like shape between the side fences 120.

[0045] As shown in FIG. 6, even if the sheets P are in a beam shape and are in close contact with each other due to static electricity or the like, a force acts in a direction separating them from each other, so the degree of contact decreases.

[0046] 7, when the sheet tray 110 is stored in the device housing, the protruding member 171 enters a retracted state in which it abuts against the recessed portion 172a. In this retracted state, the tip portion of the protruding member 171 is positioned below the bottom plate 160, so that the protruding member 171 is separated from the paper P. At this time, the paper P is placed on the bottom plate 160.

[0047] That is, when the sheet tray 110 is pulled out by the medium end moving member 170 to store new sheets of paper P, the widthwise ends of the sheets of paper P are raised above the bottom plate 160, creating a state similar to a bent beam, reducing the degree of adhesion. Thereafter, when the sheet tray 110 is stored, the bending is eliminated, and the sheets are placed on the bottom plate 160 in a loose state rather than in a tightly packed state.

[0048] 6 and 7, even when the sheet tray 110 slides in the pull-out direction from the sheet tray unit 100, the link member 172 is configured to remain in a predetermined position without being pulled out following the sheet tray 110. In contrast, the protruding member 171 is held so as to move in the same direction as the sheet tray 110 slides. Therefore, when the sheet tray 110 moves, the protruding member 171 moves but the link member 172 does not move, so the contact position between the protruding member 171 and the link member 172 changes relative to each other. The position of the protruding member 171 with respect to the bottom plate 160 changes depending on whether this contact position is the recessed portion 172a or the protruding portion 172b. Therefore, the distance between the recessed portion 172a and the protruding portion 172b is set to be equal to the distance between the protruding members 171.

[0049] The effect of the action on the sheets P as they move to the sheet tray 110 described above will be described with reference to Figure 8. As shown in Figure 8(a), it is assumed that the sheets P are in close contact with each other in the stacking direction and are arranged in blocks (bundles) of a certain number of sheets.

[0050] When the sheet tray 110 is pulled out and sheets P are stacked, the positions of the sheets P near the widthwise ends and near the widthwise center are different in the direction of gravity, so the sheets P near the widthwise center hang down, and the widthwise ends become loose in the direction of gravity, as shown in Figure 8(b). In other words, gaps are created between the sheets P that were previously in close contact, making it easy for air to get in.

[0051] 8(c), when the widthwise ends of the sheets P are no longer supported by the protruding members 171 and are placed flat on the bottom plate 160, air gets in between the individual sheets P, forming air layers and reducing the degree of adhesion. When this state is reached, the side fences 120 perform a regulating operation, so that the positions of the widthwise ends of the sheets P are regulated by the side fences 120, and the ends are aligned.

[0052] 9 is a perspective view showing a portion of the configuration of the sheet tray unit 100, illustrating a state in which the sheet tray 110 is not pulled out. As shown in Fig. 9, the bottom plate 160 is larger than the width dimension of the sheet P at a position where it supports the edge of the sheet P in the transport direction, and is smaller than the width dimension of the sheet P within the range in which the side fences 120 move to regulate the position of the edge in the width direction.

[0053] Furthermore, the link member 172 is installed inside the device housing of the sheet tray unit 100 via a compression spring 173 so as not to move following the sheet tray 110. The link member 172 is biased by the compression spring 173 in the direction opposite to the direction in which the sheet tray 110 is pulled out.

[0054] 10 illustrates a state in which the sheet tray 110 has been returned to the storage position. At this time, the link member 172 moves in a direction in which it is pressed relatively against the inside of the device housing via the compression spring 173. That is, the position of the convex portion 172b moves relative to the protruding member 171, and the protruding member 171 changes to a state in which it comes into contact with the concave portion 172a.

[0055] As a result, the protruding members 171 are lowered to a position lower than the bottom plate 160 by the action of gravity, and are no longer supporting the widthwise ends of the paper P. The paper P is then placed on the bottom plate 160, and the side fences 120 can be brought into close contact with the widthwise ends of the paper P.

[0056] [Second embodiment] Next, a second embodiment of the sheet tray unit 100 will be described with reference to Fig. 11. The sheet tray unit 100 according to this embodiment includes a blower fan 121 on the side fence 120 as a blower section.

[0057] When the sheet tray 110 is housed in the sheet tray unit 100 and the protruding member 171 is retracted relative to the link member 172, the blower fan 121 blows air toward the widthwise end of the paper P loaded on the bottom plate 160.

[0058] As explained in the first embodiment, an air layer is formed in the sheets P stacked on the bottom plate 160 due to the action of the medium end moving member 170. By blowing air toward this air layer from the width direction end, separation of the sheets P can be ensured.

[0059] The blower fan 121 sends more air into the air layer of the paper sheets P stacked on the bottom plate 160, and in this state, the side fences 120 are moved as shown in Fig. 9. This improves the alignment accuracy of the widthwise ends and reduces the transport resistance during the feeding operation.

[0060] Fig. 12 is a perspective view showing a part of the configuration of the sheet tray unit 100. As shown in Fig. 12, a blower fan 121 blows air to the widthwise ends of the sheets P stored in the bottom plate 160, so that air gets into the spaces between the sheets P from the widthwise ends, thereby reducing the degree of adhesion.

[0061] [Third embodiment] Next, a third embodiment of the sheet tray unit 100 will be described with reference to Fig. 13. Fig. 13 illustrates the regulating operation performed by the side fence 120 after the sheet tray 110 is returned to the device housing. As shown in Fig. 13, the side fence 120 performs the regulating operation of regulating the end position by pushing in the width direction end of the stacked paper P.

[0062] The amount of the regulating operation is adjusted according to the width dimension of the paper P. The regulating operation may also be an operation in which the side fence 120 repeatedly contacts and separates from the width direction end of the paper P. By repeating the contact and separation of the side fence 120 multiple times, the accuracy of regulating the position of the paper P is further improved.

[0063] 14 shows an example of the arrangement of width detection sensors 180 for detecting the width dimension of paper P. After the sheet tray 110 is stored in the sheet tray unit 100, the width dimension of paper P and the position of the side fences 120 are detected by the width detection sensors 180. The width detection sensors 180 are so-called CISs, and have multiple sensors arranged in the width direction of paper P and in the arrangement direction of the side fences 120.

[0064] The width detection sensor 180 is disposed above the paper P (see FIG. 3). The width detection sensor 180 is a line sensor in which a plurality of optical sensors are arranged in the width direction of the paper P, and is provided in the conveying unit 11. The width detection sensor 180 is disposed upstream in the conveying direction from the paper feed rollers 12 provided in the conveying unit 11, and notifies the CPU 151 of a detection signal for determining the width dimension of the paper P placed on the bottom plate 160.

[0065] The width detection sensor 180 facing the paper sheet P outputs different detection signals depending on whether the optical sensor is in a portion that detects the paper sheet P or in a portion that does not detect the paper sheet P. By determining this detection signal using the arithmetic processing function of the CPU 151, the position of the edge of the paper sheet P can be identified. The length dimension of the width detection sensor 180 and the spacing between the optical sensors are specified in advance. Therefore, by determining the detection signal, the control unit 150 can determine the width dimension of the paper sheet P.

[0066] Furthermore, when the sheet tray 110 is accommodated, the width detection sensor 180 can also detect the position of the side fence 120.

[0067] The control unit 150 detects the width dimension of the paper P and the distance between the side fence 120, and then moves the side fence 120 by a distance corresponding to the gap between the end of the paper P and the side fence 120, and abuts the side fence 120 against the end of the paper P.

[0068] Fig. 15 is a diagram illustrating a drive mechanism for the side fences 120. As shown in Fig. 15, the side fence drive unit 1250 is a mechanism that combines a side fence moving motor 1251 and a torque limiter 1252, and moves the pair of side fences 120 in a direction toward or away from the width direction ends of the paper P.

[0069] When the side fence moving motor 1251 is driven to bring the side fence 120 into contact with the widthwise end of the paper P, a torque limiter 1252 is provided to prevent the clamping force from exceeding a certain strength.

[0070] [Control flow of sheet tray unit 100] 16 is a flowchart illustrating the flow of the movement control process of the side fence 120. First, the sheet tray 110 is set in the sheet tray unit 100, and the sheet P can be supplied (S1601).

[0071] Next, the positions of the widthwise ends of the sheet P and the positions of the side fences 120 are detected based on the detection signal of the width detection sensor 180 (S1602).

[0072] Next, based on the detection result in S1602, the relative positional relationship between the widthwise end of the paper P and the side fence 120 is calculated (S1603), and the amount of movement in the regulating operation of the side fence 120 is determined according to the relative positional relationship, i.e., the size of the distance (gap) between the two (S1604).

[0073] Based on the amount of movement determined in S1604, the restricting movement of the side fence 120 is performed (S1605).

[0074] After the operation in S1605 is completed, the position of the widthwise end of the paper P and the position of the side fence 120 are detected again based on the detection signal of the width detection sensor 180, and the presence or absence of a gap between the widthwise end of the paper P and the side fence 120 is calculated, and it is determined whether or not another regulating operation is necessary (S1606).

[0075] If it is determined that the regulating operation by the side fence 120 is necessary (S1606: YES), the process returns to S1605, and the regulating operation of the side fence 120 is performed again (S1605). Thereafter, the determination of S1606 is made in the same manner. If it is determined that re-movement is not necessary (S1606: NO), the process ends.

[0076] As described above, the amount by which the side fence 120 is pressed against the paper P is varied depending on the width dimension of the paper P. Furthermore, the restricting operation is repeatedly performed depending on the situation. This improves the accuracy of aligning the width direction edges of the paper P.

[0077] That is, when the sheet tray 110 is pulled out, the side fences 120 are positioned at a position wider than the width dimension of the sheets P. Also, protruding members 171 protrude from both ends of the bottom plate 160 on which the sheets P are stacked at a position higher than the height of the bottom plate. When the user sets the sheets P, the sheets P are stacked in a beam-like state with both ends raised by the step between the bottom plate 160 and the protruding members 171. This makes it easy for air layers to get in between the sheets P. When the sheets P are stored in this state (a state in which the sheets P are easy to separate), and the side fences 120 are moved together, the widthwise ends of the sheets P can be brought into close contact with the side fences 120.

[0078] In the above-described embodiments, the medium supply device is described as the sheet tray unit 100 of the image forming apparatus, but the medium supply device may be a paper feed device externally attached to the image forming apparatus.

[0079] Furthermore, in each of the above embodiments, the sheet tray unit 100 is provided with the control unit 150. However, this is not limited to this, and the configuration equivalent to the control unit 150 may be realized by a control configuration that controls the entire image forming apparatus.

[0080] Furthermore, the present invention is not limited to the above-described exemplary embodiments, and various modifications are possible without departing from the technical gist thereof. The present invention covers all technical matters included in the technical ideas described in the claims. The above-described embodiments are preferred examples, but a person skilled in the art can realize various modifications from the disclosed content. Such modifications are also included in the technical scope described in the claims.

[0081] For example, aspects of the present invention are as follows. <1> A medium supply device that includes a medium storage unit that stores sheet-like media in a stack, and that separates and supplies the media from the medium storage unit, the medium storage unit is capable of being slidably drawn out relative to the device housing; a bottom plate on which the medium is placed; a medium position restricting member that restricts the position of the medium and faces the widthwise end of the stacked medium; When the medium storage unit is pulled out from the device housing, a vicinity of an end portion in a width direction of the medium placed on the bottom plate is moved to a position higher than the bottom plate; a medium end moving member that moves away from the vicinity of the width direction end of the medium when the medium storage unit is stored in the device housing; The medium supply device is characterized by comprising: <2> The medium position regulating member is When the medium storage unit is housed in the device housing, the medium storage unit moves toward the edge of the medium loaded on the bottom plate so as to regulate the position of the edge in the width direction. The aforementioned <1> 2 is a medium supplying device according to the first embodiment. <3> a medium size detection unit that detects the width of the medium placed on the bottom plate; The medium position regulating member is Movement toward the edge of the medium is performed in accordance with the width dimension. The aforementioned <1> or the above <2> 2 is a medium supplying device according to the first embodiment. <4> The medium position regulating member is The amount by which the edge of the medium is pushed in is varied depending on the width dimension of the medium. The aforementioned <3> 2 is a medium supplying device according to the first embodiment. <5> The medium position regulating member is repeatedly performing a regulating operation for regulating the position of the width direction end according to a positional relationship between the position of the width direction end detected by the medium dimension detection unit and the medium end moving member; The aforementioned <3> or the above <4> 2 is a medium supplying device according to the first embodiment. <6> The medium position regulating member is a blower section for blowing air to the width direction end section, before performing the regulating operation, blowing gas onto the width direction end portion; The aforementioned <5> 2 is a medium supplying device according to the first embodiment. <7> an image forming unit that forms an image on the medium; a medium supply unit that stores a stack of sheet-shaped media to be supplied to the image forming unit, The medium supply unit <1> and above <6> The media processing device according to any one of The image forming apparatus is characterized by the above. [Explanation of symbols]

[0082] 1: MFP 11: Transport section 100: Sheet tray unit 110: Sheet tray 120: Side fence 121: Blower fan 130: Elastic member 140: Drive unit 150: Control unit 160: Bottom plate 170: Media end moving member 171: Protruding member 172: Link member 172a: recess 172b: Convex part 173: Compression spring 180: Width detection sensor 1250: Side fence drive unit 1251: Side fence movement motor 1252: Torque limiter [Prior art documents] [Patent documents]

[0083] [Patent Document 1] Japanese Patent Application Publication No. 11-314768

Claims

1. A medium supply device that includes a medium storage unit that stores sheet-like media in a stack, and that separates and supplies the media from the medium storage unit, the medium storage unit is capable of being slidably drawn out relative to the device housing; a bottom plate on which the medium is placed; a medium position restricting member that restricts the position of the medium and faces the widthwise end of the stacked medium; When the medium storage unit is pulled out from the device housing, a vicinity of an end portion in a width direction of the medium placed on the bottom plate is moved to a position higher than the bottom plate; a medium end moving member that moves away from the vicinity of the width direction end of the medium when the medium storage unit is stored in the device housing; A medium supply device comprising:

2. The medium position regulating member is When the medium storage unit is housed in the device housing, the medium storage unit moves toward the edge of the medium loaded on the bottom plate so as to regulate the position of the edge in the width direction. The media feeding device of claim 1 .

3. a medium size detection unit that detects the width of the medium placed on the bottom plate; The medium position regulating member is Movement toward the edge of the medium is performed in accordance with the width dimension. The medium supply device according to claim 1 or 2.

4. The medium position regulating member is The amount by which the edge of the medium is pushed in is varied depending on the width dimension of the medium. The media supply device of claim 3 .

5. The medium position regulating member is repeatedly performing a regulating operation for regulating the position of the width direction end according to a positional relationship between the position of the width direction end detected by the medium dimension detection unit and the medium end moving member; The media supply device of claim 3 .

6. The medium position regulating member is a blower section for blowing air to the width direction end section, before performing the regulating operation, blowing gas onto the width direction end portion; The media supply device of claim 5 .

7. an image forming unit that forms an image on the medium; a medium supply unit that stores a stack of sheet-shaped media to be supplied to the image forming unit, The medium supply unit is the medium processing device according to claim 1. An image forming apparatus characterized by:

Images