JP6272083B2 - Sheet feeding apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a sheet feeding apparatus and an image forming apparatus, and more particularly to a configuration of a side end regulating unit that regulates a side end position of a sheet stored in a sheet storage unit.

  2. Description of the Related Art Today, image forming apparatuses such as copying machines, printers, and facsimiles are widely used in which an image is formed by feeding a sheet to an image forming unit using a sheet feeding apparatus. As such a sheet feeding device, there is one in which plate-like sheet stacking means for stacking sheets in a sheet storage unit is provided so as to be movable up and down. Then, when replenishing sheets, the sheet stacking means is lowered, and when feeding sheets, the upper surface of the sheets stacked by raising the sheet stacking means can be fed by the upper feeding roller. I try to move it.

  In such a sheet feeding apparatus, the position of the upstream end (hereinafter referred to as the rear end) in the sheet feeding direction of the sheets stacked on the sheet stacking unit is set in the sheet storage unit so that sheets of different sizes can be stored. Rear end regulating means for regulating is slidably provided. Further, side end regulating means for regulating the side end position of the sheet in the direction orthogonal to the sheet feeding direction (hereinafter referred to as the width direction) is slidably provided. The side edge of the sheet is regulated by the side edge regulating means, and the rear edge of the sheet is regulated by the rear edge regulating means, thereby regulating the position of the sheet to a predetermined position.

  By the way, in the conventional sheet feeding apparatus, the sheet stacking means is set to a size for stacking the maximum size sheet on which the image forming apparatus can form an image. Therefore, the sheet stacking unit is formed with a notch that allows the side end regulating unit to move in the width direction so that the side end regulating unit can move in the width direction when a sheet having a size smaller than the maximum size is stacked. Has been. However, if the notch is formed, the strength of the sheet stacking unit is reduced, so the size of the notch is limited, and accordingly, the amount of movement of the side end regulating unit in the width direction is also limited. . When the movement amount of the side edge regulating means is limited in this way, the side edge position of a small size sheet such as an envelope or a postcard may not be regulated by the side edge regulating means. For this reason, conventionally, there is a side edge restricting means provided with an auxiliary side end restricting means for restricting a small-sized sheet (see Patent Document 1).

  FIG. 14 is a diagram illustrating a configuration of a sheet storage unit of a conventional sheet feeding apparatus. In FIG. 14, 507 is a sheet storage case, 510 and 511 are side end regulating members that are provided in the sheet storage case 507 so as to be movable in the width direction, and 514 is a rear end regulating plate that is provided so as to be movable in the sheet feeding direction. It is. Reference numeral 501 denotes a feeding roller that feeds the sheet P. A separation feeding roller (not shown) that separates the sheets fed by the feeding roller 501 one by one downstream of the feeding roller 501 in the sheet feeding direction. Is provided. The sheet storage 507 is provided with a tray (not shown) that stacks the sheets P and presses the stacked sheets P against the feeding roller 501 so as to move up and down.

  At the downstream ends of the side end regulating members 510 and 511 in the sheet feeding direction, auxiliary side end regulating members 512 and 513 for regulating the end of the small-sized sheet P are rotatable about the rotation shafts 512a and 513a. Is provided. When the side end position of the small size sheet P is regulated, the auxiliary side end regulating members 512 and 513 are moved to the set position indicated by the solid line, and when the side end position of the normal size sheet is regulated, the auxiliary side end The regulating members 512 and 513 are rotated and moved to the retracted positions indicated by the two-dot chain line.

JP 2006-327805 A

  By the way, in the conventional sheet feeding device provided with the auxiliary side end regulating members 512 and 513, the auxiliary side end regulating members 512 and 513 regulate the side end position of the sheet P of the auxiliary side end regulating members 512 and 513. There is only one side 522,523. For this reason, when the auxiliary side end regulating members 512 and 513 are in the set position, the auxiliary side end regulating members 512 and 513 are arranged on the sheet P side in the region indicated by the arrow 600 on the downstream side in the sheet feeding direction shown in FIG. It cannot contact the end, and the side end position cannot be regulated. Even in the region indicated by the arrow 601 on the upstream side in the sheet feeding direction, the side end of the sheet P cannot be contacted, and the side end position cannot be restricted. That is, when the small-sized sheet P is set, the guide function indicated by the dotted lines 532, 533, 540, and 541 is not effective even if the side end position of the sheet P can be regulated by the auxiliary side edge regulating members 512 and 513. Sufficient area is created.

  And the following problem arises because the area | region where a guide function is inadequate arises. Usually, in the sheet feeding apparatus, a separating unit is arranged to separate the sheets fed by the feeding roller one by one, and a separating pad or a separating roller is often used as the separating unit. Since the separation pad and the separation roller are configured to separate the sheet by a frictional force, there is a possibility that a resistance is applied to the leading edge of the fed sheet and the leading edge of the sheet is inclined.

  In general, the sheet is regulated by arranging the side end regulating member as close to the separating means as possible so that the sheet is not inclined by the separating means, but if there is an area where the guide function is insufficient, the separating means Therefore, it is not possible to sufficiently restrict the sheet from being inclined. Therefore, the frequency of occurrence of skew (skew) in the sheet increases due to the area where the guide function is insufficient, and there is a problem that the sheet cannot be stably fed.

  The auxiliary side end regulating members 512 and 513 are retracted from the position indicated by the solid line to the position indicated by the two-dot chain line when feeding a normal size sheet. In order to move, a movement trajectory space is required. However, since the tray cannot be arranged in this movement trajectory space, the area for supporting the sheet on the tray is reduced. When the area supporting the sheets on the tray is reduced, the end of the sheet P is leaned by its own weight when the large size sheet P is stacked, and the sheet P is not properly placed on the tray. Further, if the end portion of the sheet P leans, the sheet P is bent, and at the time of feeding, the bent portion of the sheet P is caught on the tray and becomes a paper jam.

  SUMMARY An advantage of some aspects of the invention is that it provides a sheet feeding apparatus and an image forming apparatus that can stably feed even a small-sized sheet. Is.

  In the sheet feeding apparatus, the sheet stacking unit on which the sheet bundle is stacked and the side end position in the width direction perpendicular to the sheet feeding direction of the sheet bundle stacked on the sheet stacking unit are regulated. A sheet storage unit having a pair of side end regulating means, at least one of which is movable in the width direction, and the uppermost sheet of the sheet bundle provided above the sheet stacking unit and stacked on the raised sheet stacking unit. A sheet feeding unit that feeds in contact with the sheet and a sheet that is detachably attached to the upper surface of the sheet stacking unit, and has a shorter length in the width direction than a sheet whose side end position can be regulated by the pair of side end regulating units. Auxiliary sheet stacking means for stacking sheets, and when the auxiliary sheet stacking means is attached to the sheet stacking section, it is attached to the inner wall surface facing at least one sheet bundle of the pair of side end regulating means. And an auxiliary side end restricting means for restricting a side end position of the sheet bundle stacked on the auxiliary sheet stacking means. The auxiliary side end restricting means is an auxiliary attached to the side end restricting means. A side end regulating member and a lower auxiliary side end regulating member supported by the auxiliary side end regulating member so as to be movable in the vertical direction and projecting downward from the auxiliary side end regulating member. It is.

  As in the present invention, when feeding a small-sized sheet having a short length in the width direction, an auxiliary side end regulating unit is attached to the side end regulating unit, and an auxiliary sheet stacking unit is attached to the upper surface of the sheet stacking unit. Even small size sheets can be fed stably.

1 is a diagram illustrating an overall configuration of a full-color laser beam printer which is an example of an image forming apparatus including a sheet feeding device according to an embodiment of the present invention. The figure which showed the state which pulled out the storage from the paper deck attached to the said full color laser beam printer. The figure explaining the state which controls the side edge position of a sheet | seat with the auxiliary side guide attached to the side control member provided in the said storage. The figure which shows a state when the envelope accommodated in the said storage is piled up. The figure explaining the structure of the attachment set to the said storage. The figure explaining the state when a normal size sheet | seat is accommodated in the said storage. The figure explaining operation of the side control member when storing a normal size sheet | seat in the said storage. The figure explaining the structure of the intermediate plate provided in the said storage. The figure explaining operation | movement of the said attachment and auxiliary | assistant side guide at the time of sheet | seat feeding. The control block diagram of the said paper deck. FIG. 6 is a first diagram illustrating an operation of the paper deck during sheet feeding. The 2nd figure explaining operation | movement at the time of sheet | seat feeding of the said paper deck. The figure explaining the other structure of the said attachment. The figure explaining the structure of the sheet storage part of the conventional sheet feeding apparatus.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram illustrating an overall configuration of a full-color laser beam printer which is an example of an image forming apparatus including a sheet feeding device according to an embodiment of the present invention.

  In FIG. 1, reference numeral 201 denotes a full-color laser beam printer (hereinafter referred to as a printer), 201A denotes a printer main body that is an image forming apparatus main body, 201B denotes an image forming unit that forms an image on a sheet, and 220 denotes a fixing unit. An image reading apparatus 202 is an upper apparatus installed substantially horizontally above the printer main body 201A. A discharge space S for discharging sheets is formed between the image reading apparatus 202 and the printer main body 201A. .

  Reference numeral 230 denotes a sheet feeding device provided at the lower portion of the printer main body 201A, and 300A denotes a manual paper feed unit provided on one side of the printer main body 201A and provided with an open / close tray 300 that can be manually fed. Reference numeral 101 denotes a large-capacity paper deck connected to one side of the printer main body 201A. Reference numeral 215 denotes a toner cartridge.

  The image forming unit 201B is of a four-drum full color type, and forms four toner images of the laser scanner 210 and four colors of yellow (Y), magenta (M), cyan (C), and black (K). The process cartridge 211 is provided. Here, each process cartridge 211 includes a photosensitive drum 212, a charger 213 as a charging unit, a developing unit 214 as a developing unit, and a cleaner as a cleaning unit (not shown). In addition, the image forming unit 201B includes an intermediate transfer unit 201C disposed above the process cartridge 211.

  The intermediate transfer unit 201C includes an intermediate transfer belt 216 wound around a driving roller 216a and a tension roller 216b. The intermediate transfer unit 201 </ b> C includes a primary transfer roller 219 that is provided inside the intermediate transfer belt 216 and that contacts the intermediate transfer belt 216 at a position facing the photosensitive drum 212. Here, the intermediate transfer belt 216 is formed of a film-like member and is disposed so as to be in contact with each photosensitive drum 212, and is rotated in a direction indicated by an arrow by a driving roller 216a driven by a driving unit (not shown). ing.

  Then, by applying a positive transfer bias to the intermediate transfer belt 216 by the primary transfer roller 219, each color toner image having a negative polarity on the photosensitive drum is sequentially transferred to the intermediate transfer belt 216 in a multiple manner. As a result, a color image is formed on the intermediate transfer belt. A secondary transfer roller 217 constituting a secondary transfer portion that transfers a color image formed on the intermediate transfer belt to the sheet P is provided at a position facing the driving roller 216a of the intermediate transfer unit 201C.

  Further, a fixing unit 220 is disposed above the secondary transfer roller 217, and a first discharge roller pair 225a, a second discharge roller pair 225b, and a double-side reversing unit that is a reverse discharge unit are disposed on the upper left side of the fixing unit 220. 201D is arranged. The double-side reversing unit 201D is provided with a reversing roller pair 222, which is a sheet reversing and conveying roller capable of normal and reversal, and a reconveying path R that conveys a sheet on which an image is formed to the image forming unit 201B again. .

  The sheet feeding device 230 includes a cassette 233 and a pickup roller 231 that feeds out the sheet P stored in the cassette 233. The paper deck 101 includes a storage 7 that is a sheet storage unit that stacks and stores a large number of sheets P, and a sheet feeding device 102 that feeds the sheets stored in the storage 7. The storage 7 is provided so as to be capable of being pulled out with respect to the housing 6, and includes a lifter tray 8 that is a sheet stacking unit that can stack and lift the sheets. The lifter tray 8 is suspended by a wire or the like (not shown), and can be controlled up and down by winding or unwinding a wire pulley connected to a motor.

  The sheet feeding device 102 includes a feeding roller 1 that is a sheet feeding unit that feeds the sheets stacked on the lifter tray 8, and a separation unit that separates and transports the sheets fed by the feeding roller 1 one by one. A feed roller 2 and a retard roller 3 are provided. The feed roller 1, the feed roller 2, and the retard roller 3 are rollers in which a member having a high friction coefficient such as rubber is wound around the outer periphery.

  In FIG. 1, reference numeral 400 denotes a control unit (control unit) that controls the image forming operation of the printer main body 201A, the sheet feeding device 102, and the sheet feeding operation of the large capacity paper deck 101. S1 is a position sensor for detecting the position of the feeding roller 1 and stopping the lifter tray 8 at a position where the sheet can be fed by the feeding roller 1 when the lifter tray 8 is raised, as will be described later.

  Next, an image forming operation of the printer 201 will be described. First, when image information of a document is read by the image reading device 202, the image information is subjected to image processing, converted into an electrical signal, and transmitted to the laser scanner 210 of the image forming unit 201B. In the image forming unit 201 </ b> B, the surface of the photosensitive drum 212 whose surface is uniformly charged to a predetermined polarity and potential by the charger 213 is sequentially exposed by laser light. As a result, yellow, magenta, cyan, and black electrostatic latent images are sequentially formed on the photosensitive drums of the process cartridges 211, respectively.

  Thereafter, the electrostatic latent image is developed and visualized with each color toner, and each color toner image on each photoconductive drum is sequentially superimposed on the intermediate transfer belt 216 by the primary transfer bias applied to the primary transfer roller 219. Transfer together. As a result, a toner image is formed on the intermediate transfer belt 216.

  In parallel with this toner image forming operation, the sheet P stored in the cassette 233 is sent out by the pickup roller 231 provided in the sheet feeding device 230. The fed sheets P are separated one by one by the separation unit 232 and conveyed to the registration roller pair 240, and the skew feeding is corrected by the registration roller pair 240. In addition, when manually feeding, the sheet set on the open / close tray 300 is conveyed toward the registration roller pair 240 by the feeding roller 250.

  Further, when paper feeding from the paper deck 101 is designated, the sheet is fed out from the feeding roller 1, and the fed-out sheet is conveyed to the registration roller pair 240 by the feed roller 2 and the drawing roller 4. There are cases where two or more sheets are sent out by the feeding roller 1. In this case, the retard roller 3 prevents the second and subsequent sheets from entering the nip portion of the feed roller 2 and the retard roller 3. Thus, only the first sheet is conveyed.

  After the skew is corrected, the sheet P is conveyed to the secondary transfer unit by the registration roller pair 240, and the toner image is transferred to the sheet by the secondary transfer bias applied to the secondary transfer roller 217 in the secondary transfer unit. Transferred onto P in batch. Next, the sheet P to which the toner image has been transferred is conveyed to the fixing unit 220, and the toner of each color is melted and mixed by receiving heat and pressure in the fixing unit 220, and is fixed on the sheet P as a color image.

  Thereafter, the sheet P on which the image is fixed is discharged to the discharge space S by the first discharge roller pair 225a and the second discharge roller pair 225b provided downstream of the fixing unit 220, and protrudes to the bottom surface of the discharge space S. It is loaded on the loading unit 223. When forming an image on both sides of the sheet P, after the image is fixed, the sheet P is conveyed to the reconveying path R by the reversing roller pair 222 and is conveyed again to the image forming unit 201B.

  FIG. 2 is a view showing a state in which the storage 7 provided on the paper deck 101 so as to be freely drawn out in the direction indicated by the arrow 51 is pulled out from the paper deck 101 in the forward direction. When storing sheets on the paper deck 101, the storage 7 is pulled out and the sheets are stacked on the lifter tray 8.

  In FIG. 2, 9 is a slide rail disposed on the upstream outer wall surface in the sheet feeding direction of the storage case 7, and is a slide rail for pulling out the storage case 7 from the housing 6. It is also arranged on the outer wall surface on the downstream side in the feed direction. Reference numerals 10 and 11 denote a pair of side regulating members that regulate the side end positions in the width direction orthogonal to the sheet feeding direction of the sheet bundle stacked on the lifter tray 8. The side regulating members 10 and 11 can regulate the position of the side edge of the sheet as long as at least one of the side regulating members 10 and 11 can move in the width direction, but in the present embodiment, both can move in the width direction. Reference numeral 30 denotes a trailing edge regulating member that regulates the position of the trailing edge that is the upstream edge of the sheet in the sheet feeding direction.

  Then, after the sheets are stacked on the lifter tray 8, the side regulating members 10, 11 and the trailing end regulating member 14 are set according to the size of the sheet P. Thereafter, when the storage 7 is closed, the lifter tray 8 is raised, The uppermost sheet of the sheet P contacts the feeding roller 1. Thereafter, when the lifter tray 8 further rises and the feed roller 1 is further pushed up, the position sensor S1 detects the raised feed roller 1, and the control unit 400 stops the lift of the lifter tray 8 by a signal from the position sensor S1. To do. As a result, the position of the upper surface of the uppermost sheet becomes a position where the sheet can be fed by the feeding roller 1. When feeding of the sheet P is started and the height of the sheet bundle is lowered, the feeding roller 1 is lowered. When this is detected by a signal from the position sensor S1, the control unit 400 feeds the lifter tray 8 to the feeding roller 1. The roller 1 is raised until the position sensor S1 detects it.

  By the way, in the present embodiment, the paper deck 101 may store a small-sized sheet having a shorter length in the width direction than a sheet capable of regulating the side end position by the side regulating members 10 and 11. The lifter tray 8 is formed with a notch so that the side regulating members 10 and 11 can move according to the size of the sheet. However, in terms of strength, the side regulating members 10 and 11 restrict the small size sheet. It is not possible to form a notch that can be moved up to. In the following description, postcards and envelopes are referred to as small-size sheets, sheets such as A4 and B4 are referred to as normal-size sheets, and A3 sheets are referred to as maximum-size sheets.

  Therefore, when storing a small-sized sheet, as shown in FIG. 3, the back side auxiliary side guide 50 is attached to the restriction surface side that is the inner wall surface facing the sheet bundle of the back side side restriction member 10 by a magnet or the like. Removably attach. Further, the front auxiliary side guide 51 is detachably attached to the restriction surface side of the front side restriction member 11 with a magnet or the like.

  Here, auxiliary side guides 50 and 51, which are auxiliary side end regulating means for regulating the side end position of the small-size sheet bundle, regulate the side end position of the upper part of the sheet bundle as shown in FIG. Side guide main bodies 50a and 51a, which are upper auxiliary side end regulating members, are provided. The auxiliary side guides 50, 51 are provided on the side guide main bodies 50a, 51a so as to be slidable in the vertical direction, and are auxiliary slide guides 52, which are lower auxiliary side end regulating members for regulating the lower side end position of the sheet bundle. 53. The auxiliary slide guides 52 and 53 normally project downward from the side guide bodies 50a and 51a by their own weight so as to regulate the side end position of the lower part of the sheet bundle.

  The auxiliary side guides 50 and 51 have a length in the sheet feeding direction that can regulate the entire side end of a small-sized sheet. Further, by attaching the auxiliary side guides 50 and 51 having such a length to the side regulating members 10 and 11, even when a small-size sheet is stored, the sheet can be reliably regulated, and the sheet is skewed. It is possible to prevent the occurrence of poor feeding. In particular, since the auxiliary side guides 50 and 51 are provided with a restriction region having substantially the same length in the sheet feeding direction as that of the side restriction members 10 and 11, there is almost no free region, and skewing occurs in the sheet. There is nothing.

  In the present embodiment, the paper deck 101 can also store envelopes having different thicknesses at both ends in the width direction as sheets having a short length in the width direction. Here, when the sheet is an envelope, the envelope is provided with a flap 23 for closing the sealing opening as shown in FIG. And since this flap 23 is not the shape which covers the whole surface of the envelope P, but the shape which covers a part, in the envelope P, the part covered with the flap 23 becomes thicker than another part. That is, the envelope P is formed in a bag shape by folding the sheet, and further, since the flap 23 is folded at the end portion, a portion having a thickness of two sheets and a portion having a thickness of three sheets. There is.

  Therefore, when the envelopes P are stacked in the same direction, the height H1 on the side with the flap 23 becomes higher than the height H2 on the side without the flap 23. As the number of envelopes P to be stacked increases, the difference between the heights H1 and H2 of the bundles of envelopes P increases, and the uppermost envelope P1 is greatly inclined in the width direction. Then, when the envelope is stacked on the paper deck 101 with the folded portion on the side where the flap 23 is located in the sheet feeding direction, the uppermost envelope P1 is inclined in the width direction. Only one end in the width direction of the feeding roller 1 contacts the upper surface of the uppermost envelope. When the one end of the feeding roller 1 comes into contact with the uppermost envelope P1, the feeding roller 1 cannot evenly contact the upper surface of the envelope. In this case, since the feeding force of the feeding roller 1 is not uniformly transmitted to the envelope P1, feeding failure due to slip and skewing due to one-sided contact occur.

  Therefore, when the envelope P is stored, the auxiliary side guides 50 and 51 are attached to the side regulating members 10 and 11, and the attachment 40 which is auxiliary sheet stacking means for horizontally holding the uppermost sheet stacked on the lifter tray 8 is provided. Is attached to the upper surface of the lifter tray 8. As shown in FIG. 5, the attachment 40 is a swing member that is a swing member that is supported on the upper surface of the base member 15 and swings in the vertical direction along the width direction via the swing shaft 18. Plates 16 and 17 are provided. When the attachment 40 is attached to the lifter tray 8, the lower end (lower surface) of the envelope P stacked on the attachment 40 is positioned higher than the upper surface of the lifter tray 8 by the height of the attachment 40. When the attachment 40 is attached, the fact that the lower surface of the sheet bundle such as the envelope P is above the upper surface of the lifter tray 8 is called raising.

  Here, the two swing plates 16 and 17 are independent of each other so that the uppermost envelope P is parallel when there is a difference in the stacking height of the envelopes P due to the difference in thickness at both ends in the width direction. Can swing in the direction of the arrow. Further, the upper surface of the base member 15 is inclined so that the downstream side in the sheet feeding direction becomes higher. As described later, when the envelope is fed by the feeding roller 1, the envelope P is sent obliquely upward. It is.

  6A and 6B are side views showing the state of the paper deck 101 when stacking sheets of normal size. FIG. 6A shows a state before the sheets P are stacked, and FIG. A state in which the sheets P are stacked is shown. FIG. 7 is a view of the paper deck 101 viewed from the sheet feeding direction when sheets are stacked. FIG. 7A shows a state in which the side regulating members 10 and 11 are in a position to regulate the side edge position of the maximum size sheet. The side regulating members 10 and 11 at this time are indicated by arrows 90. It is an interval.

  FIG. 7B shows a state in which the side regulating members 10 and 11 are moved in the width direction in order to store a normal size sheet. The side regulating members 10 and 11 at this time are stored. The interval is indicated by an arrow 91 corresponding to the size of the sheet to be printed. When the sheet is fed, the sheet P is placed on the upper surface of the lifter tray 8, the rear end of the sheet P is pressed by the rear end regulating member 30, and the side end position of the sheet is regulated by the side regulating members 10 and 11. Then, the sheet is fed by the feeding roller 1.

  In the present embodiment, the lifter tray 8 is provided with a notch 8a so that the side regulating members 10, 11 can be moved in the width direction according to the sheet size, as shown in FIG. It has been. The lifter tray 8 is formed with a long hole 8b extending in the sheet feeding direction so that the trailing edge regulating member 30 can slide. FIG. 8A shows a state in which the side regulating members 10 and 11 are in a position for regulating the side end position of the maximum size sheet. FIG. 8B shows a state in which the side regulating members 10 and 11 are in a position for regulating the side end position of a narrow sheet among the sheets capable of regulating the side end position by the side regulating members 10 and 11. Is shown.

  Here, in the lifter tray 8, when the cutout amount in the width direction of the cutout portion 8a is increased, the strength is reduced and the side edge portion of the sheet hangs down from the cutout portion 8a, and the sheet is cut out when the sheet is fed. 8a may cause a feeding failure. Therefore, in the present embodiment, as shown in FIG. 8, the lifter tray 8 has a stacking surface for supporting sheets together with the lifter tray 8, and the auxiliary trays 80 and 81 for supporting the side edges of the sheets are arranged in the width direction. Is slidably provided. The auxiliary trays 80 and 81 are slid in conjunction with the side regulating members 10 and 11.

  FIG. 8A shows a state in which the auxiliary trays 80 and 81 are pulled out, and by pulling out the auxiliary trays 80 and 81 in this way, the side end portions of the sheets of the normal size and the maximum size are displayed. Can be supported. FIG. 8B shows a state where the side regulating members 10 and 11 are set at a position where the interval in the width direction is the narrowest. At this time, the auxiliary trays 80 and 81 are attached to the side regulating members 10 and 11. Interlocked and stored in the lower surface of the lifter tray 8.

  By the way, as described above, the size of the notch portion of the notch portion 8a that can be formed in the lifter tray 8 is limited in terms of strength and the like, and when the size of the notch portion 8a is thus limited, The amount of movement of the side regulating members 10, 11 in the width direction is limited. For this reason, when a small size sheet such as an envelope is stacked on the lifter tray 8, the side end position of the sheet is regulated using the side regulating members 10, 11 due to the restriction of the movement amount of the side regulating members 10, 11. I can't.

  Therefore, in the present embodiment, when storing a small-sized sheet such as the envelope P, for example, the attachment 40, the back side auxiliary side guide 50, and the front side auxiliary side guide 51 are attached as shown in FIG. When the attachment 40 is set, a projection (not shown) provided on the back surface of the attachment 40 is fitted into a positioning hole (not shown) on the upper surface of the lifter tray 8. When the auxiliary side guides 50 and 51 are set, a projection (not shown) provided on the auxiliary side guides 50 and 51 is fitted in a positioning hole (not shown) provided on the side regulating members 10 and 11. Attach it with a magnet.

  FIG. 9A is a view showing a state when the attachment 40 and the auxiliary side guides 50 and 51 are attached. At this time, the lifter tray 8 is in a lowered state. In FIG. 9A, an arrow 92 indicates the distance in the width direction of the auxiliary side guides 50 and 51 when attached to the side regulating members 10 and 11, and this distance is the length in the width direction of the envelope. Is almost equal.

  FIG. 9B is a diagram illustrating a state when the sheet is fed and the lifter tray 8 is raised to the upper limit position. Here, when the auxiliary side guides 50 and 51 are attached to the side regulating members 10 and 11, the auxiliary slide guides 52 and 53 are located in a region through which the lifter tray 8 passes. For this reason, when the lifter tray 8 rises, the lifter tray 8 contacts the auxiliary slide guides 52 and 53 protruding downward.

  However, as described above, the auxiliary slide guides 52 and 53 are provided on the side guide main bodies 50a and 51a so as to be slidable in the vertical direction, so that the lifter tray 8 rises while pushing up the auxiliary slide guides 52 and 53. Thereafter, when the uppermost sheet of the sheet bundle supported by the attachment 40 abuts on the feeding roller 1 to push up the feeding roller 1 and the position sensor S1 detects the raised feeding roller 1, the lifter tray 8 is raised. Stop.

  Note that when the sheets are sequentially fed and the height of the sheet bundle is lowered, the feeding roller 1 is lowered, and when this is detected by a signal from the position sensor S1, the control unit 400 moves the lifter tray 8 to the feeding roller 1. Is raised until the position sensor S1 detects it. At this time, the lifter tray 8 rises while pressing the auxiliary slide guides 52 and 53, and the auxiliary slide guides 52 and 53 slide into the side guide main bodies 50a and 51a.

  As described above, the side guide main bodies 50a and 51a are fixed to the side regulating members 10 and 11 with magnets. This is because the side guide bodies 50a and 51a can be easily attached, and the side guide bodies 50a and 51a can be easily detached when the mechanism for raising the lifter tray 8 is electrically runaway. . That is, when the lifter tray 8 does not stop based on the detection of the position sensor S1, the magnet is removed even if the lifter tray 8 collides with the side guide bodies 50a and 51a, and the side guide bodies 50a and 51a are not damaged.

  FIG. 10 is a control block diagram of the paper deck 101 according to the present embodiment. As shown in FIG. 10, the above-described position sensor S <b> 1, a sheet presence / absence detection sensor S <b> 2 that detects the presence / absence of a sheet on the lifter tray 8, and an elevating mechanism 401 that moves the lifter tray 8 up and down are connected to the control unit 400. .

  Next, the operation of the paper deck 101 during sheet feeding will be described. First, a sheet feeding operation when a small-sized sheet is set on the paper deck 101 instead of an envelope will be described. FIG. 11A is a view showing a state in which the attachment 40 is set on the lifter tray 8. Thereafter, when the sheets P are stacked, the sheet P tends to move downstream in the sheet feeding direction due to the inclination of the base member 15 described above, but is slidable along the sheet feeding direction indicated by the arrow 20. Movement is regulated by the end regulating member 30. In FIG. 11, reference numeral 14 denotes a front wall portion that is provided on the downstream side in the sheet feeding direction of the storage 7 and restricts the movement of the sheet P stored in the storage 7 to the downstream side in the sheet feeding direction.

  When the sheet bundle is set and the storage case 7 is closed, the elevating mechanism 401 is driven. Then, as the sheet stacking amount decreases due to the sheet feeding, the lifter tray 8 rises as shown in FIG. 11B, the auxiliary slide guide 52 is pushed up by the lifter tray 8, and the inside of the side guide body 50a. Get in. Although not shown, the auxiliary slide guide 53 is similarly pushed up by the lifter tray 8 and enters the side guide main body 51a. FIG. 11 (c) shows a state where the lifter tray 8 is further raised, and is raised to the upper limit position and stopped. When there is no more sheet on the lifter tray (on the sheet stacking portion), the flag of the sheet presence / absence detection sensor S2 enters the hole 16a formed in the swing plate 16 on the downstream side of the attachment 40, and the absence of sheet is detected. The lift of the lifter tray 8 is stopped.

  Next, the operation of the lifter tray 8 when an envelope is set on the paper deck 101 will be described. FIG. 12A is a diagram showing a state in which the envelopes P are stacked with the attachment 40 set on the lifter tray 8. Here, when the envelope P is loaded, the envelope P tends to move downstream in the sheet feeding direction due to the inclination of the base member 15 described above, but the movement of the envelope P is restricted by the trailing edge regulating member 30. .

  When the bundle of envelopes P is set, the swinging plates 16 and 17 can swing along the width direction, so the side where the stacking height is high in the width direction, that is, the side where the envelope flaps are located, As a fulcrum, the side with lower loading height goes up. That is, when the envelopes P having different thicknesses in the width direction are stacked, the end on which the thicker end of the sheet is placed on the other end in the width direction of the swing plates 16 and 17 is the other end. It swings so as to be lower than the part. That is, it swings in the direction in which the uppermost surface of the loaded envelope P becomes horizontal.

  Further, when the swing plates 16 and 17 are swung so that the lifter tray 8 is lifted and the feeding roller 1 comes into contact with the uppermost envelope P, the uppermost envelope P1 of the stack of envelopes to be stacked becomes substantially horizontal. Become. That is, as in the present embodiment, the swinging plates 16 and 17 can be freely tilted according to the weight of the bundle of envelopes P, so that the uppermost envelope P1 of the bundle of envelopes P can be removed. It can be brought into contact with the feeding roller 1 in a substantially horizontal state. And by making the uppermost envelope P1 substantially horizontal, the envelope P1 can be sent out without causing the feed roller 1 to come into contact with the uppermost envelope P1 evenly and slip evenly. .

  FIG. 12B shows a state where the lifter tray 8 is raised and stopped at the upper limit position for detecting the absence of a sheet based on the output of the sheet presence / absence detection sensor S2. Here, the upper limit position of the lifter tray 8 is a position where the auxiliary slide guides 52 and 53 are inserted into the side guide main bodies 50a and 51a at the maximum. This upper limit position is set so that when the lifter tray 8 reaches the upper limit position, the last envelope P1 of the bundle of envelopes stacked is fed. And in order to set an upper limit position in such a position, in this Embodiment, the length of the height direction of the side guide main bodies 50a and 51a and the height of the attachment 40 are made substantially the same.

  That is, it is necessary to prevent the lower ends of the side guide bodies 50a and 51a from colliding when the lifter tray 8 is raised. For this reason, the lifter tray 8 is stopped when the absence of a sheet is detected based on the detection of the sheet presence / absence detection sensor S2, but the side guide bodies 50a and 51a are prevented from colliding with the lifter tray 8 until this stop. When the attachment 40 is mounted, the position at which the lifter tray 8 stops based on the absence of the sheet is positioned below the raised distance from the case where the attachment 40 is not mounted. Therefore, the side guide bodies 50a and 51a are moved to the side regulating members 10 and 11 in a state where the side guide main bodies 50a and 51a are lowered to a position below the stop position of the lifter tray 8 when there is no seat when not attached to the attachment 40. Can be attached.

  When the last envelope on the lifter tray 8 is sent out, the flag of the sheet presence / absence detection sensor S2 enters the hole 16a formed on the surface of the swing plate 16 on the downstream side of the attachment 40 as shown in FIG. Accordingly, a signal indicating that there is no envelope on the lifter tray 8 is input from the sheet presence / absence detection sensor S2, and the control unit 400 detects that there is no envelope on the lifter tray 8, and stops the rise at the upper limit position of the lifter tray 8. .

  Thus, in the present embodiment, the upward movement of the lifter tray 8 from the upper limit position can be restricted by stopping the lift control of the lifter tray 8 based on the signal from the sheet presence / absence detection sensor S2. it can. Thereby, damage to the lifter tray 8 and the side guide bodies 50a and 51a due to the lift of the lifter tray 8 can be prevented.

  Here, when the auxiliary side guides 50 and 51 are attached to the side regulating members 10 and 11 as in the present embodiment, the lift of the lifter tray 8 rises as shown in FIG. 9B. Limited by.

  As described above, when the auxiliary side guides 50 and 51 are attached, the lift amount of the lifter tray 8 is reduced by the length of the side guide main bodies 50a and 51a in the height direction. However, even when the lift amount of the lifter tray 8 decreases, all the envelopes loaded on the lifter tray 8 can be fed.

  When the attachment 40 is set, the number of envelopes P that can be stacked is reduced by the height of the attachment 40. Here, as described above, when a plurality of envelopes P are stacked by the flap as described above, the upper surface height of the uppermost envelope P1 becomes uneven. The upper surface of the uppermost envelope P1 can be made uniform by the swing plates 16 and 17 up to a certain number of stacked sheets. However, if the number of stacked sheets increases, the swing of the swing plates 16 and 17 alone is the maximum. The upper surface height of the upper envelope P1 cannot be kept uniform.

  For this reason, in order to keep the upper surface height of the uppermost envelope P1 uniform, it is necessary to limit the number of sheets that can be stacked. Therefore, by setting the attachment 40 as in the present embodiment, the number of sheets that can be stacked is limited, but the upper surface height of the uppermost envelope P1 can be made constant. That is, when stacking envelopes, by using the attachment 40, it is possible to stack by an amount that can maintain the upper surface height of the uppermost envelope P1 more uniformly.

  FIG. 13A shows a state in which the envelope bundle PA having a non-uniform height is stacked on the lifter tray 8. At this time, the swing plate 16 provided in the attachment 40 swings, and the uppermost envelope P1 becomes horizontal. However, for example, in an envelope, there is an envelope bundle having a non-uniform height, that is, a uniform height depending on how the envelope flaps are folded.

  Therefore, when it is desired to load a bundle of envelopes that are not uneven and have a narrow width, as shown in FIG. The swing of the plate 16 is restricted, and the upper surfaces of the swing plates 16 and 17 are kept horizontal. The fixing plate 54 can be fitted and fixed to the attachment 40, and can be easily removed when not in use.

  As described above, in the present embodiment, the auxiliary side guides 50 and 51 are attached to the side regulating members 10 and 11 and attached to the upper surface of the lifter tray 8 when regulating the side end position of the small-sized sheet bundle. 40 is attached. By attaching the auxiliary side guides 50 and 51, even a small-sized sheet can be stably fed without being skewed by the auxiliary side guides 50 and 51. Moreover, since the sheet bundle is raised by attaching the attachment 40, the auxiliary side guides 50 and 51 can be supported at a position where the side end can be regulated, so that the sheet can be fed stably. .

  Heretofore, the case where the auxiliary side guides are respectively attached to the pair of side regulating members has been described. However, the present invention is not limited thereto, and the auxiliary side guide is attached to at least one of the pair of side regulating members. Also good. Further, the case where the auxiliary side guide is fixed to the side regulating member using a magnet has been described so far, but the present invention is not limited to this, and other fixing means may be used.

  DESCRIPTION OF SYMBOLS 1 ... Feeding roller, 7 ... Storage, 8 ... Lifter tray, 10, 11 ... Side regulating member, 15 ... Base member, 16, 17 ... Swing plate, 30 ... Rear end regulating member, 40 ... Attachment, 50, 51 Auxiliary side guide 50a, 51a Side guide body 52, 53 Auxiliary slide guide 101 Paper deck 102 Sheet feeding device 201 Full color laser beam printer 201A Printer body 201B Image forming unit , 400 ... control unit, 401 ... lifting mechanism, P ... sheet (envelope), PA ... sheet bundle (envelope bundle), S1 ... position sensor, S2 ... sheet presence / absence detection sensor

Claims (8)

A pair of sheet stackers that can be moved up and down on which the sheet bundle is stacked, and at least one of the sheet bundles stacked on the sheet stacking section that is capable of moving in the width direction at least one of the side end positions that are orthogonal to the sheet feeding direction. A sheet storage portion having the side edge regulating means,
A sheet feeding unit provided above the sheet stacking unit and configured to contact and feed the uppermost sheet of the sheet bundle stacked on the raised sheet stacking unit;
An auxiliary sheet stacking unit that is detachably attached to the upper surface of the sheet stacking unit and stacks a sheet having a shorter length in the width direction than a sheet capable of regulating the side end position by the pair of side end regulating units;
When the auxiliary sheet stacking unit is mounted on the sheet stacking unit, the auxiliary sheet stacking unit is detachably mounted on an inner wall surface facing at least one sheet bundle of the pair of side end regulating units, and is stacked on the auxiliary sheet stacking unit. Auxiliary side end regulating means for regulating the side end position of the sheet bundle,
The auxiliary side end regulating means is supported by the auxiliary side end regulating member attached to the side end regulating means and the auxiliary side end regulating member so as to be movable in the vertical direction, and protrudes downward from the auxiliary side end regulating member. And a lower auxiliary side end regulating member.   When the auxiliary side end restricting means is attached to the side end restricting means, the lower auxiliary side end restricting member is located in an area through which the sheet stacking portion passes and rises. The sheet feeding apparatus according to claim 1, wherein the sheet feeding apparatus moves upward as the height of the sheet increases.   3. The sheet feeding according to claim 1, wherein the auxiliary side end regulating unit has a length in a sheet feeding direction capable of regulating a whole side end of a sheet having a short length in the width direction. Feeding device. Elevating means for elevating and lowering the sheet stacking unit;
Detection means for outputting a signal corresponding to the presence or absence of a sheet on the sheet stacking unit;
4. The sheet according to claim 1, further comprising: a control unit that controls the lifting unit to stop the lifting of the sheet stacking unit based on a signal from the detection unit. Feeding device.   5. The sheet feeding device according to claim 1, wherein the auxiliary sheet stacking unit includes a swinging member swingable in a vertical direction along a width direction in which the sheet bundle is stacked. Feeding device.   When sheets having different thicknesses in the width direction are stacked, the swinging member has an end on which the thicker end of the sheet is placed among both ends in the width direction of the swinging member. 6. The sheet feeding device according to claim 5, wherein the sheet feeding device swings so as to be lower than the end portion.   The auxiliary sheet stacking means includes the swing member and a base member that supports the swing member, and two swing members are attached to the base member along the sheet feeding direction. The sheet feeding apparatus according to claim 5 or 6, wherein the sheet feeding apparatus is characterized in that: An image forming unit for forming an image on a sheet;
An image forming apparatus comprising: the sheet feeding apparatus according to claim 1, which feeds a sheet to the image forming unit.

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