JP2006008357A - Paper feeder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper feeder capable of feeding a large amount of sheets and suppressing any conveying jam of sheets. <P>SOLUTION: The paper feeder 1 comprises a plurality of paper feed units 1a-1c. Each of the paper feed units 1a-1c has a loading plate 2 to load paper sheets S as an example of the sheets to be fed to an image forming device 100, and arranged parallel to the side of the image forming device 100. The top surface of the paper sheets S stored on the loading plates 2 of the paper feed units 1a-1c is higher toward the paper feed unit 1c arranged on the upstream side in the conveying direction of the paper sheets S, and lower toward the paper feed unit 1a arranged on the downstream side. The paper sheets S are conveyed to the image forming device 100 from the paper feed unit 1c with the paper sheets S stored therein through the highest surface of the paper sheets S stored on the loading plates 2 of the paper feed units 1a, 1b arranged on the downstream side in the conveying direction of the paper sheets S. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a sheet feeding device including a plurality of sheet feeding units each having a sheet path that stores a sheet body to be supplied to a main apparatus in a storage position and conveys the sheet body from the storage position toward the main apparatus. The present invention relates to a sheet feeding device that stores a large number of sheet bodies.

  An image forming apparatus is an example of a main apparatus that receives a sheet body such as a sheet from a sheet feeding apparatus. In recent years, multifunctional image forming apparatuses and printing processing speeds have been increased. For example, an image forming apparatus having a plurality of processing modes such as a copier mode, a printer mode, and a FAX mode, and a printing processing speed of one sheet or more per second has been developed. Such a high-speed image forming apparatus requires a paper feeding device capable of supplying a large amount of paper. The necessity is remarkably exhibited in the printer mode and the FAX mode in which printing is performed even when there is no user near the image forming apparatus. In particular, in the FAX mode, a large-capacity paper feeding device as described above is indispensable. When storing a large amount of information received when the user is absent at night or the like in a memory in the image forming apparatus without printing in order to prevent running out of paper, a large-capacity memory is required and the information stored in the memory is stored later. This is because time is lost when printing.

As a means for supplying a large amount of paper to the image forming apparatus, a means for increasing the capacity of a paper feed cassette conventionally provided in the image forming apparatus and a paper feed cassette provided in the image forming apparatus are provided in the image forming apparatus. Means for arranging a large capacity sheet feeding device adjacent to each other can be considered. However, when the capacity of the paper feed cassette provided in the image forming apparatus is increased, there is a problem that the image forming apparatus becomes higher overall, and the operation unit and the display unit become higher, resulting in lower operability. Under such circumstances, development of a large-capacity paper feeding device that is disposed adjacent to the image forming apparatus apart from the paper feeding cassette provided in the image forming apparatus is underway (for example, see Patent Document 1). ).
JP-A-5-193766

  However, even with a large-capacity paper feeder as described above, the number of sheets stored cannot be increased without limit. The number of sheets stored is generally limited to 2000 to 4000 sheets. This is because the paper feeder has a lift-up mechanism that adjusts the height of the paper bundle at any time in order to sequentially feed the topmost paper. However, if the number of sheets stored is too large, the weight of the paper bundle becomes too high. This is because the up mechanism needs to have a sturdy configuration, which increases the size and cost of the apparatus, and makes it difficult to precisely adjust the paper height.

  In view of this, Japanese Patent Laid-Open No. 2004-228561 proposes a paper feeding device that includes a plurality of paper storage positions in order to increase the number of stored sheets, and each storage position is arranged in several stages in the vertical direction. The paper supplied from the paper supply device is received from a paper receiving portion that communicates with the paper conveyance path of the image forming apparatus. Since the sheet receiving unit of the image forming apparatus needs to communicate with the sheet conveyance path, the position where the sheet receiving unit is provided is limited. Therefore, in the paper feeding device described in Patent Document 1, a bent portion is formed in the conveyance path in the paper feeding device from the storage position arranged at a different height from the paper receiving portion of the image forming apparatus to the paper receiving portion. The opportunity for the conveyed paper to bend in the paper feeder increases, and the paper tends to bend unnecessarily. Unnecessary bending of the paper causes a conveyance jam and a decrease in print quality. Further, in the paper feeder disclosed in Patent Document 1, if the amount of paper stored is increased, the paper storage positions are further stacked in the vertical direction, the transport path is further complicated, and the occurrence of a transport jam is likely to occur.

  In order to solve the above-described problems, the applicant of the present invention proposes a paper feeding device including a plurality of paper feeding units configured to be arranged in parallel with the main device. As a result, the opportunity to bend the conveyed paper is reduced compared to the prior art, and it is possible to suppress the occurrence of a conveyance jam due to unnecessary bending of the paper. However, even in such a sheet feeding device, it is necessary to take measures for suppressing the jam of the sheet conveyed between the sheet feeding units arranged in parallel.

  An object of the present invention is to provide a sheet feeding device capable of supplying a large amount of sheet bodies and suppressing sheet jams.

  The paper feeding device of the present invention is configured as follows in order to solve the above-described problems.

  (1) A plurality of sheet feeding units that convey the sheet body stored in the storage position in the transport direction from the storage position toward the main apparatus are arranged in parallel in the transport direction, and each of the paper feed units is stored. The uppermost surface of the sheet body stored in the position is arranged such that the sheet feeding unit arranged on the upstream side in the conveyance direction is higher and the sheet feeding unit arranged on the downstream side in the conveyance direction is lower, The main device passes the sheet body stored in the storage position of the sheet feeding unit via the uppermost surface of the sheet body stored in the storage position of the sheet feeding unit disposed further downstream in the transport direction. It is characterized by being conveyed to.

  In this configuration, the sheet feeding device includes a plurality of sheet feeding units, and each sheet feeding unit is configured to be arranged in parallel to the side of the main device. Since the paper supply units are arranged in parallel, the conveyance paths of the respective paper supply units are arranged in a substantially straight line, and the sheet body is conveyed without being bent in the conveyance direction. In addition, the uppermost surface of the sheet body stored in the storage position of each sheet feeding unit is higher in the sheet feeding unit disposed on the upstream side in the sheet conveyance direction, and is disposed on the downstream side in the sheet conveyance direction. Since the sheet unit is arranged so as to be lower, the sheet body projects from the upstream sheet feeding unit to the downstream sheet feeding unit via the uppermost surface of the sheet body stored in the storage position. It is transported smoothly without any problems.

  (2) Each of the paper feeding units has a discharge portion that is open to the outside on the downstream side in the transport direction, and another paper feed that is open to the outside on the upstream side in the transport direction and is adjacent to the upstream side in the transport direction. And a receiving portion that can communicate with the discharging portion provided in the unit.

  In this configuration, each paper feed unit includes a discharge unit and a reception unit. The discharging unit and the receiving unit are opened to the outside on each of the downstream side and the upstream side in the transport direction. The receiving unit can communicate with a discharge unit provided in another sheet feeding unit adjacent to the upstream side in the conveyance direction of the sheet body, and from the receiving unit to another sheet feeding unit located on the upstream side in the conveyance direction. The sheet body conveyed via the uppermost surface of the stored sheet body is received.

  (3) The receiving unit may be disposed at the same height as a discharge unit of another sheet feeding unit adjacent to the upstream side in the transport direction.

  In this configuration, since the receiving unit is disposed at the same height as the discharge unit of the other sheet feeding unit adjacent to the upstream side in the sheet conveyance direction, the conveyance paths of the sheet feeding units adjacent to each other are easy. In addition, the sheet body is conveyed from the upstream sheet feeding unit to the downstream sheet feeding unit without being bent.

  (4) Each of the sheet feeding units includes the receiving unit at a position higher than the discharge unit.

  In this configuration, the discharge portion from which the sheet body stored in the storage position is discharged is disposed at substantially the same height as the upper surface of the uppermost sheet body among the sheet bodies stored in the storage position, and is received. The part is provided at a position higher than the discharge part. Therefore, the sheet body received from the receiving unit is conveyed onto the upper surface of the uppermost sheet body without being struck by the sheet body stored in the storage position.

  (5) Each of the sheet feeding units is connected to the discharge unit or the receiving unit, the receiving unit of another sheet feeding unit adjacent to the downstream side in the transport direction, or another adjacent to the upstream side in the transport direction. It further comprises a guide member for connecting the discharge unit of the paper feed unit.

  In this configuration, each paper feed unit includes a guide member in the discharge unit or the reception unit. When the guide member is provided in the discharge unit, the guide member connects the receiving unit of another sheet feeding unit adjacent to the downstream side in the transport direction, and the sheet member discharged from the discharge unit is connected to the sheet member. The paper is guided to another paper feeding unit adjacent to the downstream side in the transport direction. Further, when the guide member is provided in the receiving unit, the guide member connects the discharge unit of another paper feed unit adjacent to the upstream side in the transport direction and is adjacent to the upstream side in the transport direction of the sheet member. The sheet body discharged from the discharge unit of the sheet feeding unit is guided into the receiving unit.

  (6) The distal end portion of the guide member on the downstream side in the transport direction is above the upper surface of the uppermost sheet member stored in the storage position of another paper feed unit adjacent to the downstream side in the transport direction. In addition, the sheet member is disposed on the downstream side from the upstream end of the sheet member stored in the storage position of another sheet feeding unit adjacent to the downstream side in the transport direction.

  In this configuration, the downstream end portion of the guide member is disposed above the upper surface of the uppermost sheet member accommodated in another paper feed unit adjacent to the downstream side, and thus has passed through the guide member. The sheet member is conveyed above the uppermost sheet member stored in the storage position of another sheet feeding unit adjacent to the downstream side. In addition, the downstream end of the guide member is disposed downstream of the upstream end of the sheet body stored in the storage position of another paper feed unit adjacent to the downstream side, so that it passes through the guide member. The sheet body thus conveyed is reliably conveyed to the sheet body stored in the storage position of another paper feed unit adjacent on the downstream side.

  (7) Each of the sheet feeding units is disposed on the downstream side of the pickup member, the pickup member supplying the uppermost sheet member stored in the storage position to the downstream side of the conveyance direction, and the pickup member A conveyance member that conveys the supplied sheet body, and the distance between the conveyance member and the pickup member provided in another sheet feeding unit adjacent to the downstream side in the conveyance direction is the sheet It is shorter than the dimension of the said body in the said conveyance direction.

  In this configuration, the distance between the conveying member and the pickup member of another sheet feeding unit adjacent to the downstream side in the sheet conveying direction is shorter than the dimension in the sheet conveying direction. Therefore, the sheet body is gripped by the pickup member of another sheet feeding unit adjacent to the downstream side while being gripped by the conveying member.

  (8) A sheet member of the same size is stored in a storage position of the plurality of sheet feeding units.

  In this configuration, since a sheet body of the same size is stored in the storage position of a plurality of paper feed units, the transport member and the pickup member provided in another paper feed unit adjacent to the downstream side in the transport direction Even when the distance is unified, the sheet is gripped by the pickup member of another sheet feeding unit adjacent to the downstream side while being gripped by the transport member.

  According to the present invention, the following effects can be obtained.

  (1) The sheet body is transported without being bent in the transport direction, and the sheet body is not subjected to unnecessary bending in the transport direction, so that it is possible to suppress oblique transport and transport jam of the sheet body. In addition, since the sheet body is conveyed without sticking from the upstream sheet feeding unit to the downstream sheet feeding unit, it is possible to suppress conveyance jam between adjacent sheet feeding units. Further, since the sheet body is transported via the upper surface of the uppermost sheet body stored in the storage position, it is not necessary to provide a separate transport path as in the prior art, and the paper feeding device can be made compact. Can do.

  (2) Since the discharge unit and the receiving unit communicate with each other, the conveyance paths of a plurality of paper feed units can be continued.

  (3) Since the sheet member is conveyed from the upstream sheet feeding unit to the downstream sheet feeding unit without being bent, unnecessary sheet bending can be prevented and sheet jam can be suppressed. .

  (4) Since the sheet body received from the receiving unit is transported onto the upper surface of the uppermost sheet body without striking the sheet body stored in the storage position, it is possible to suppress a conveyance jam between adjacent sheet feeding units. can do.

  (5) Conveyance jam between adjacent paper feeding units can be further suppressed.

  (6) The sheet member that has passed through the guide member is reliably conveyed to above the uppermost sheet member without striking the sheet member stored in the storage position of another sheet feeding unit adjacent to the downstream side. Can do.

  (7) Since the sheet body is gripped by the pickup member of another sheet feeding unit adjacent to the downstream side while being gripped by the transport member, the transport force of the sheet body is not interrupted, and the transport jam is suppressed. can do.

  (8) Even when the distance between the conveyance member and the pickup member provided in another sheet feeding unit adjacent to the downstream side in the conveyance direction is unified, the conveyance force of the sheet body is not interrupted, and the conveyance jam is suppressed. Can do. Therefore, the workability of manufacturing a plurality of paper feeding units arranged in parallel can be improved.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing a schematic configuration of a sheet feeding device 1 according to an embodiment of the present invention. The paper feeding device 1 according to this embodiment includes a plurality (three in this embodiment) of paper feeding units 1a, 1b, and 1c. The plurality of sheet feeding units 1a, 1b, and 1c are arranged in parallel on the side of the image forming apparatus 100, which is an example of a main apparatus that receives a sheet. In this embodiment, the sheet feeding device 1 supplies the sheet S as an example of a sheet body to the image forming apparatus 100, but can also supply other sheet bodies such as an OHP film. Further, the same size paper S is stored in the plurality of paper feeding units 1a to 1c arranged in parallel.

  The image forming apparatus 100 forms an image on the paper S through an electrophotographic image forming process. The image forming apparatus 100 includes paper feed cassettes 102 and 103 at the bottom and a paper discharge tray 104 at the top. A paper transport path F <b> 1 is provided between the paper feed cassettes 102 and 103 and the paper discharge tray 104. A photosensitive drum 105 is disposed in the vicinity of the paper transport path F1. Around the photosensitive drum 105, a charging device 106, an optical scanning unit 107, a developing unit 108, a transfer device 109, a cleaning unit 110, and a static elimination device (not shown) are disposed. In addition, a registration roller 111 that adjusts the timing of supplying the paper S to the transfer unit between the photosensitive drum 105 and the transfer device 109 is disposed upstream of the photosensitive drum 105 in the conveyance direction of the paper S. A fixing device 112 is disposed downstream of the drum 105.

  The charging device 106 charges the outer peripheral surface of the photosensitive drum 105 to a predetermined potential. The optical scanning unit 107 forms an electrostatic latent image on the outer peripheral surface of the photosensitive drum 105 based on image data input from the outside. The developing unit 108 supplies toner onto the outer peripheral surface of the photosensitive drum 105 to visualize the electrostatic latent image, and forms a toner image. The toner image formed on the photosensitive drum 105 is transferred to the paper S by the transfer device 109, further fixed to the paper S by the fixing device 111, and discharged to the paper discharge tray 104. The toner remaining on the outer peripheral surface of the photosensitive drum 105 after the toner image is transferred to the paper S is collected by the cleaning unit 110, and the electric charge on the outer peripheral surface of the photosensitive drum 105 is removed by the static eliminator.

  Further, the image forming apparatus 100 includes a reversal conveyance path F2 for reversing the front and back of the sheet and conveying the image to the transfer unit in order to form an image on the back side of the sheet on which the image is formed on one side. Further, the image forming apparatus 100 includes a paper transport path F3 that joins the paper transport path F1 between the paper feed cassettes 102 and 103 and the transfer unit. The paper transport path F3 is provided substantially horizontally. The sheet conveyance path F3 leads to a manual feed tray 113 that is provided on a side surface of the image forming apparatus 100 and supplies a non-standard size sheet, and a sheet receiving unit 114 that receives a sheet S supplied from an external apparatus. The paper S supplied from the tray 113 or the paper receiving unit 114 is conveyed to the transfer unit. The sheet S fed from the sheet feeding units 1a to 1c is supplied from the sheet receiving unit 114 of the image forming apparatus 100 to the sheet transport path F3 and is transported to the transfer unit.

  FIG. 2 is a cross-sectional view showing a schematic configuration of the paper feeding unit 1c. The paper feeding unit 1c includes a mounting plate 2, a pickup roller 3 as a pickup member, a feed roller 4, a reverse roller 5, a conveyance roller 6 as a conveyance member, a discharge unit 7, and paper guides 8 and 9 as guide members. The receiving part 10 is provided.

  The paper S is positioned by the paper positioning plate 16 and stored in a stacked state on the placement plate 2 which is the storage position. The paper feed unit 1 c is formed on the placement plate 2 so as to be able to store a large amount of paper. The mounting plate 2 is moved up and down along the guide rails 13 and 14 by the lifting members 11 and 12, and the vertical position is detected by the detection sensor 15. The elevating members 11, 12 move the mounting plate 2 in the vertical direction so that the upper surface of the uppermost sheet S in the sheet bundle placed on the mounting plate 2 is at a predetermined position 18 in the height direction. Displace. Here, the detection sensor 15 also detects whether or not the sheet S is on the placement plate 2.

  The placement plate 2 is positioned at the lowest position when the paper S is replenished, and in this state, the paper S is replenished to an arbitrary position below the height of the paper loading capacity index 17. In addition, the loading plate 2 includes a paper feeding unit arranged on the upstream side in the conveyance direction of the paper S from the paper feeding unit 1c, and the paper S fed from the upstream paper feeding unit is being conveyed. When there is no paper S on the placement plate 2 of the paper feeding unit 1c, the placement plate 2 is not lowered to the lowest position, and the upper surface of the placement plate 2 is arranged at the height of the position 18. The

  The pickup roller 3 is formed so as to be displaceable in the vertical direction. The pickup roller 3 is lowered when a paper feed request is made, and feeds the uppermost paper S in the paper bundle placed on the placement plate 2. The feed roller 4 and the reverse roller 5 are disposed on the downstream side of the pickup roller 3 in the transport direction of the paper S so as to face each other. The feed roller 4 is rotationally driven in the same direction as the pickup roller 3. The reverse roller 5 is rotationally driven so that the circumferential surface moves in the direction opposite to the circumferential surface of the feed roller 4. The paper S fed by the pickup roller 3 is fed by the feed roller 4 and the reverse roller 5 and supplied to the transport path R one by one.

  A transport roller 6 is disposed downstream of the feed roller 4 and the reverse roller 5 in the transport direction of the paper S. On the transport path R and on the downstream side of the transport roller 6, a discharge unit 7 that opens to the outside of the paper feed unit 1c is provided. The sheet S fed by the pickup roller 3 and rolled by the feed roller 4 and the reverse roller 5 is further conveyed downstream by the conveying roller 6 and is discharged from the discharge unit 7 to the outside of the sheet feeding unit 1c.

  Paper guides 8 and 9 are disposed in the discharge unit 7. Each of the paper guides 8 and 9 is formed to be rotatable, and is displaced between a folded state along the side surface of the paper feeding unit 1c and a use state supported in the horizontal direction. When the paper guides 8 and 9 are set to the use state, the paper guides 8 and 9 connect the receiving unit 10 of the other paper feeding unit 1b adjacent to the downstream side and guide the paper S discharged from the discharge unit 7. . In addition, the paper guides 8 and 9 may be provided in the receiving unit 10 and may be connected to the discharge unit 7 of another paper feeding unit adjacent to the upstream side.

  A receiving unit 10 opened to the outside is provided on the upstream side of the conveyance path R of the paper S and on the side surface opposite to the side surface of the paper feeding unit 1c where the discharge unit 7 is provided. In FIG. 2, the discharge unit 7 and the receiving unit 10 are arranged at substantially the same height, but actually, the receiving unit 10 is provided at a position higher than the discharge unit 7 by a predetermined dimension as shown in FIG. 1. The receiving unit 10 is open to the outside of the paper feed unit 1c, and receives the paper S supplied from the outside of the paper feed unit 1c into the paper feed unit 1c. The discharge unit 7 and the receiving unit 10 are formed so that the conveyance path R can communicate with each other when the plurality of paper feed units 1a to 1c are arranged in parallel in the same direction.

  The paper feed units 1a and 1b are configured similarly to the paper feed unit 1c except for the height. The paper feeding unit 1b is formed such that the height of the receiving unit 10 of the paper feeding unit 1b is the same as the height of the discharge unit 7 of the paper feeding unit 1c. The paper feeding unit 1a is a receiving unit of the paper feeding unit 1a. The height 10 is the same as the height of the discharge portion 7 of the paper feed unit 1b. Further, the placement table 2 of each of the paper feeding units 1 a to 1 c is higher on the upper surface of the uppermost paper S among the papers S stored on the placement table 2 of the paper feeding unit 1 c far from the image forming apparatus 100. Of the sheets S stored on the mounting table 2 of the sheet feeding unit 1a close to the image forming apparatus 100, the upper surface of the uppermost sheet S is arranged to be lower. Further, the paper guides 8 and 9 of the paper feeding unit 1 a adjacent to the image forming apparatus 100 are inserted into the paper receiving unit 114 of the image forming apparatus 100.

  The sheet feeding units 1 a to 1 c configured as described above are arranged in parallel on the side of the image forming apparatus 100. The paper feed unit 1 a is formed lower than the manual feed tray 113 so that the paper S can be supplied to the paper receiving unit 114 of the image forming apparatus 100 without interfering with the manual feed tray 113 of the image forming apparatus 100. In the following description, the relationship between the paper feed unit 1b and the paper feed unit 1c will be mainly described, but the same applies to the relationship between the paper feed unit 1a and the paper feed unit 1b. The sheet S is transported in the direction (leftward in FIG. 1) from the sheet feed unit 1c farthest to the image forming apparatus 100 to the sheet feed unit 1a.

  In each of the paper feeding units 1b and 1c, the receiving unit 10 of the paper feeding unit 1b arranged on the downstream side in the transport direction of the paper S and the discharge unit 7 of the paper feeding unit 1c arranged on the upstream side face each other. Are arranged in parallel in the horizontal direction. The paper guides 8 and 9 of the paper feeding units 1b and 1c are set in use and are inserted into the receiving portions 10 of the paper feeding units 1a and 1b adjacent to the downstream side, respectively. By inserting the paper guides 8 and 9 into the receiving portions 10 of the paper feeding units 1a and 1b adjacent to the downstream side, the conveyance path R of the upstream paper feeding units 1b and 1c and the downstream paper feeding units 1a and 1a, The conveyance path R of 1b is communicated.

  FIG. 3 is a partially enlarged view of the sheet feeding device 1. The paper guides 8 and 9 of the paper feeding unit 1c are mounted on the paper feeding unit 1b when the paper feeding units 1b and 1c are arranged in parallel and inserted into the receiving portion 10 of the paper feeding unit 1b adjacent to the downstream side. The upstream end Q of the paper S placed on the placement plate 2 of the paper feeding unit 1b above the upper surface of the uppermost paper S in the paper bundle placed on the placement plate 2. It is formed so that the downstream end portion P is disposed further downstream. As a result, the sheet S conveyed from the sheet feeding unit 1c does not stick to the sheet S stored in another sheet feeding unit 1b adjacent to the downstream side, and the sheet S stored in the sheet feeding unit 1b. Is smoothly conveyed to the top surface of the.

  As shown in FIG. 1, in a state where the paper feeding units 1b and 1c are arranged in parallel, the distance L1 between the pickup roller 3 of the downstream paper feeding unit 1b and the transport roller 6 of the upstream paper feeding unit 1c. Is set to be shorter than the dimension L2 of the transported paper S in the transport direction. Specifically, for example, in the conventional paper feeding unit, the pickup roller is disposed so as to feed the paper at a position of 10 mm to 20 mm from the edge of the paper on the placing plate. In the units 1b and 1c, the pickup roller 3 is disposed so as to feed the paper S at a position of 50 mm to 60 mm from the front end portion of the paper S arranged on the placement plate 2. As a result, the sheet S is gripped by the pickup roller 3 of the sheet feeding unit 1 b and conveyed by the pickup roller 3 while being gripped by the conveying roller 6 of the sheet feeding unit 1 c and being conveyed by the conveying roller 6. Therefore, even when the paper S is transported via the plurality of paper feeding units 1b and 1c, the transport force for the paper S is not interrupted, and the transport jam is suppressed.

  The paper S supplied from the upstream paper feed unit 1c and received from the receiving unit 10 is placed on the upper surface of the uppermost paper S in the paper bundle placed on the placement plate 2 of the paper feed unit 1b. Guided and transported. That is, the upper surface of the uppermost sheet S in the sheet bundle placed on the placing plate 2 constitutes a part of the transport path R. When there is no sheet S on the placement plate 2, the sheet S being conveyed is guided and conveyed by the upper surface of the placement plate 2. In this case, the upper surface of the mounting plate 2 constitutes a part of the transport path R.

  By the driving force of the transport roller 6 of the upstream paper feed unit 1c, the paper is transported on the upper surface of the uppermost paper S in the paper stack placed on the placement plate 2 of the downstream paper feed unit 1b. The sheet S is gripped at the front end by the pickup roller 3 of the sheet feeding unit 1b that descends at a predetermined timing while being gripped by the transport roller 6 of the sheet feeding unit 1c, and is picked up by the pickup roller 3 of the sheet feeding unit 1b. Further, the sheet is conveyed and further conveyed further downstream by the conveying roller 6 of the sheet feeding unit 1b.

  As described above, in the paper feeding device 1 according to the present invention, the paper S stored in the paper feeding unit 1c is fed on the conveyance path R of the paper feeding unit 1c and on the downstream side of the paper feeding unit 1c. It is conveyed to the image forming apparatus 100 via the conveyance path R of the units 1a and 1b. That is, the conveyance path R of each of the sheet feeding units 1a and 1b in which the sheet feeding unit disposed on the upstream side exists is for conveying the sheet S stored in each sheet feeding unit 1a and 1b itself, and each sheet feeding unit. It is commonly used for conveying the paper S stored in the paper feeding units 1b and 1c arranged upstream of 1a and 1b.

  FIG. 4 is a diagram illustrating a configuration of a comparative example for the sheet feeding device 1. For convenience of explanation, the same reference numerals as those of the paper feeding device 1 are used. In the paper feeder shown in FIG. 4, the height of the uppermost paper S in the paper bundle stored in the paper supply unit 1c and the uppermost paper S in the paper bundle stored in the paper supply unit 1b. The height is set to be approximately the same. In this case, the paper guides 8 and 9 arranged in the discharge unit 7 of the paper feeding unit 1c are arranged at substantially the same height as the uppermost paper S in the paper bundle stored in the paper feeding unit 1c. The height of the paper guides 8 and 9 of the paper feeding unit 1c is substantially the same as the height of the upper surface of the uppermost paper S in the paper bundle stored in the paper feeding unit 1b. Accordingly, the downstream end P of the paper guides 8 and 9 of the paper supply unit 1c does not collide with the paper S stored in the paper supply unit 1b, so that the paper S stored in the paper supply unit 1b does not collide. It arrange | positions upstream from the edge part Q of an upstream. In the above case, as shown in FIG. 4, the sheet S conveyed from the sheet feeding unit 1 c is changed to the sheet S stored in the sheet feeding unit 1 b as the leading end of the sheet S bends downward. The paper jam occurs between the paper feed unit 1c and the paper feed unit 1b.

  According to the paper feeding device 1, the uppermost surface of the paper S stored in the paper feeding unit 1c arranged on the upstream side in the conveyance direction of the paper S is higher and is stored in the paper feeding unit 1b arranged on the downstream side. Since the uppermost surface of the sheet S is set to be lower, the sheet S conveyed from the upstream sheet feeding unit 1c does not cause the above-described sticking, and the downstream sheet feeding unit The sheet bundle stored in 1b is conveyed onto the upper surface of the uppermost sheet S, and then further downstream while being guided by the upper surface of the uppermost sheet S in the sheet bundle stored in the sheet feeding unit 1b. Smoothly transported to the side.

  Further, according to the sheet feeding device 1, the sheet S is conveyed without being bent in the conveyance direction, and the sheet S is not subjected to unnecessary bending in the conveyance direction, so that the oblique conveyance and conveyance jam of the sheet S can be suppressed. . Further, since the upper surface of the uppermost sheet S in the sheet bundle placed on the placing plate 2 forms a part of the transport path R, it is not necessary to provide a separate transport path as in the prior art. The paper device 1 can be made compact. Furthermore, since the discharge unit 7 and the receiving unit 10 communicate with each other, the transport paths R of the plurality of paper feed units 1a to 1c can be made continuous.

  Further, since the paper guides 8 and 9 are provided in the discharge unit 7, the transport path R provided in another paper feed unit adjacent to the downstream side in the transport direction of the paper S for the paper S discharged from the discharge unit 7. It is possible to guide the sheet smoothly, and it is possible to further suppress the conveyance jam between the adjacent sheet feeding units.

  Further, while being gripped by the paper S and the transport roller 6, it is gripped by the pickup roller 3 of another paper feeding unit adjacent to the downstream side, so that the transport force of the paper S is not interrupted and transport jam is suppressed. can do.

  Further, when a paper jam of the paper S to be supplied to the image forming apparatus 100 occurs, toner adheres to the transfer device 109 in the transfer unit of the image forming apparatus 100, and a transfer failure occurs in the next process. Further, unfixed toner that has not been transferred to the paper S is collected by the cleaning unit 110 disposed around the photosensitive drum 105, but the amount of toner becomes enormous and the load on the cleaning unit 110 increases. Further, the unfixed toner that has not been transferred to the paper S causes scattering inside the apparatus. As described above, when the paper S is jammed, a number of problems such as transfer failure of the image forming apparatus 100, an increase in the load of the cleaning unit 110, and scattering of toner in the apparatus are caused. The cost required for printing increases. On the other hand, according to the paper feeding device 1, the conveyance jam of the paper S can be suppressed, so that the above-described problems can be suppressed and the cost required for printing on one paper S can be reduced. Can do.

  In the above-described embodiment, the downstream end P of the paper guides 8 and 9 is the uppermost sheet in the sheet bundle placed on the placing plate 2 of the sheet feeding unit 1b adjacent to the downstream side. Although it is located above the upper surface of S and downstream of the upstream end Q of the paper S placed on the placement plate 2 of the paper feeding unit 1b, it is not limited to this.

  For example, as shown in FIG. 5, the leading end P on the downstream side of the paper guides 8 and 9 is placed at the top of the sheet bundle placed on the placement plate 2 of the paper feed unit 1b adjacent to the downstream side. The sheet S may be arranged at a predetermined dimension M above the upper surface of the sheet S and upstream from the end Q on the upstream side of the sheet S placed on the placing plate 2 of the sheet feeding unit 1b. In this case, the dimension M and the dimension N are determined based on the thickness, size, moisture content, and the like of the paper S. In many cases, the dimension M and the dimension N are substantially equal and pass through the paper guides 8 and 9. Even when the leading edge of the sheet S being conveyed is bent downward, the upper surface of the uppermost sheet S among the sheet bundles placed on the placing plate 2 of the sheet feeding unit 1b adjacent to the downstream side. Is set to be conveyed. The dimension M and the dimension N are set to any dimension between several mm and several tens mm. Note that the smaller the dimension M and the dimension N, the smaller the height difference between the sheet feeding units 1a to 1c. Therefore, as shown in FIG. 3, the downstream end P of the paper guides 8 and 9 is the uppermost of the sheet bundles placed on the placing plate 2 of the sheet feeding unit 1b adjacent to the downstream side. When the paper S is disposed above the upper surface of the paper S and on the downstream side of the upstream end Q of the paper S placed on the placement plate 2 of the paper feeding unit 1b, each of the paper feeding units 1a to 1b. Conveyance jam of the paper S can be suppressed while the height difference of 1c is minimized.

1 is a cross-sectional view illustrating a schematic configuration of a sheet feeding device according to an embodiment of the present invention. FIG. 3 is a cross-sectional view illustrating a schematic configuration of a paper feeding unit. FIG. 2 is a partially enlarged view of the sheet feeding device illustrated in FIG. 1. It is the figure which showed the structure of the comparative example. It is the elements on larger scale which show the structure of the paper feeder which concerns on other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Paper feeder 1a, 1b, 1c Paper feed unit 2 Mounting plate 3 Pickup roller 6 Conveyance roller 7 Discharge part 8,9 Paper guide 10 Receiving part 100 Image forming apparatus R Conveyance path S Paper

Claims (8)

A plurality of sheet feeding units that convey the sheet body stored in the storage position in the transport direction from the storage position toward the main device are provided in parallel with the transport direction so as to be freely arranged.
The uppermost surface of the sheet body stored in the storage position of each of the paper feed units is higher as the paper feed unit is disposed upstream in the transport direction, and is higher in the paper feed unit disposed downstream in the transport direction. Arranged to be lower,
The main device passes the sheet body stored in the storage position of the sheet feeding unit via the uppermost surface of the sheet body stored in the storage position of the sheet feeding unit disposed further downstream in the transport direction. A paper feeding device characterized in that Each of the paper feeding units includes a discharge unit that is open to the outside on the downstream side in the transport direction;
The apparatus further comprises: a receiving portion that is open to the outside on the upstream side in the transport direction and communicates with a discharge portion provided in another paper feed unit adjacent to the upstream side in the transport direction. The sheet feeding device according to 1.   The sheet feeding device according to claim 2, wherein the receiving unit is disposed at the same height as a discharge unit of another sheet feeding unit adjacent to the upstream side in the transport direction.   The sheet feeding device according to claim 3, wherein each of the sheet feeding units includes the receiving unit at a position higher than the discharge unit.   Each of the sheet feeding units includes a receiving section of another sheet feeding unit adjacent to the discharge section or the receiving section on the downstream side in the transport direction, or another sheet feeding unit adjacent to the upstream side in the transport direction. The sheet feeding device according to claim 2, further comprising a guide member that couples the discharge unit to the discharge unit.   The leading end portion of the guide member on the downstream side in the transport direction is above the upper surface of the uppermost sheet member stored in the storage position of another paper feed unit adjacent to the downstream side in the transport direction, and The sheet feeding device according to claim 5, wherein the sheet feeding unit is disposed downstream of an upstream end portion of a sheet body stored in a storing position of another sheet feeding unit adjacent to the downstream side in the transport direction. apparatus. Each of the sheet feeding units includes a pickup member that supplies the uppermost sheet body stored in the storage position to the downstream side in the transport direction;
A conveying member that is disposed on the downstream side of the pickup member and conveys a sheet body supplied by the pickup member;
The distance between the conveying member and the pickup member provided in another sheet feeding unit adjacent to the downstream side in the conveying direction is shorter than the dimension of the sheet member in the conveying direction. The paper feeding device according to any one of 1 to 6.   The sheet feeding device according to claim 7, wherein sheet bodies of the same size are stored in the storage positions of the plurality of sheet feeding units.

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