Patent Application
20080185766
1. Field of the Invention
The present invention relates to a sheet processing apparatus that feeds a sheet having an image formed thereon by a copying machine, a printer, a multifunction peripheral (MFP), or the like to a finisher and has a collating function.
2. Description of the Related Art
In recent years, among image forming apparatuses, there is an image forming apparatus in which a finisher is provided adjacent to an image forming apparatus main body in order to perform post-processing such as processing for sorting sheets after image formation and processing for applying staple processing to the sheets. An inserter may be arranged at a pre-stage of the finisher in order to feed sheets having images formed thereon to the finisher.
In a general inserter, since a user needs to arrange orders of sheets to be inserted in advance and insert the sheets, a burden is imposed on the user.
In JP-A-2001-270653, a collating device is described. In this example, prints are supplied from plural printing machines to plural trays on a belt conveyor, respectively, and the prints received by the trays are collected and stacked to collate the prints. However, in this example, since the plural trays and the belt conveyor are necessary, the apparatus is large in scale.
In JP-A-10-186741, an original conveying apparatus that copies plural originals by the number n and sorts the copies is described. In this example, a system for varying discharge speed at the time when a first sheet is discharged and at the time when second to nth sheets are discharged on the basis of the number of copies n is adopted.
However, since it is necessary to frequently switch discharge speed of the sheets, a structure of the apparatus is complicated.
Moreover, in JP-A-9-48531, a supplying apparatus that supplies sheets to a collating machine to bind the sheets is described. This example is a large-scale apparatus for bookbinding.
The present invention provides a sheet processing apparatus and a sheet processing method that can classify sheets into predetermined states and discharge the sheets.
Throughout this description, the embodiments and examples shown should be considered as exemplars, rather than limitations on the apparatus of the present invention.
An embodiment of the invention will be hereinafter explained in detail with reference to the drawings. In the respective figures, identical components are denoted by identical reference numerals and signs.
An original stand (not shown) is provided above a main body 11 of the image forming apparatus 10. An auto document feeder (ADF) 12 is provided to be opened and closed freely on the original stand. An operation panel 13 is provided on the main body 11. The operation panel 13 has an operation unit 14 including various keys and a display unit 15 of a touch panel type.
The main body 11 has a scanner unit 16 and a printer unit 17 in the inside thereof. Plural cassettes 18 having sheets of various sizes stored therein are provided below the main body 11. The scanner unit 16 scans an original sent by the ADF 12 or an original placed on the original stand.
The printer unit 17 includes a photoconductive drum and a laser, scans and exposes the surface of the photoconductive drum with a laser beam from the laser, and forms an electrostatic latent image on the photoconductive drum. A charging device, a developing device, a transfer device, and the like are arranged around the photoconductive drum. The electrostatic latent image on the photoconductive drum is developed by the developing device and a toner image is formed on the photoconductive drum. The toner image is transferred onto a sheet by the transfer device.
A constitution of the printer 17 is not limited to the above example. There are various systems as the constitution of the printer 17. A finisher 20 is arranged on a sheet discharge side of the image forming apparatus 10. A sheet having an image formed thereon by the image forming apparatus 10 is conveyed to the finisher 20.
The finisher 20 performs post-processing for the sheet supplied from the image forming apparatus 10 and performs, for example, sort processing and staple processing. When necessary, the finisher 20 folds the sheet in two and discharges the sheet.
The finisher 20 shown in
The sheet discharge tray 51 is a movable type and receives the sheet bundle subjected to the staple processing. The stapling mechanism 21 includes an aligning device that aligns sheets, which are conveyed to the stapling mechanism 21, in a width direction. The stapling mechanism 21 can also sort and discharge the sheets using this aligning device.
When the post-processing such as stapling is not performed, the stapling mechanism 21 directly discharges the sheets conveyed from the image forming apparatus 10 to the sheet discharge tray 51 or the fixed tray 52 without applying any processing to the sheets.
The stapling mechanism 21 of the finisher 20 will be briefly explained. Sheets supplied from the image forming apparatus 10 via the punching mechanism 31 are received by inlet rollers 22 provided near a delivery port of the finisher 20. Sheet feeding rollers 23 are provided on a downstream side of the inlet rollers 22. Sheets P received by the inlet rollers 22 are stacked on a processing tray 24 via the sheet feeding rollers 23 and the like.
The sheets stacked on the processing tray 24 are guided to a stapler 25 and subjected to staple processing. A conveyor belt 26 for conveying the sheets P subjected to the sort processing and the staple processing to the sheet discharge tray 51 is provided.
The sheets P conveyed by the conveyor belt 26 are discharged to the sheet discharge tray 51. The sheet discharge tray 51 is lifted and lowered by a driving unit (now shown) to receive the sheets P.
The sheets P may be discharged to the sheet discharge tray 51 without being subjected to the staple processing. In this case, the sheets P are discharged without being dropped to the processing tray 24. It is also possible to discharge the sheets P for which the post-processing is unnecessary to the fixed tray 52. A conveying path is provided in order to guide the sheets P to the fixed tray 52. The conveying path is not shown in the figure.
The punching mechanism 31 will be explained. The punching mechanism 31 is arranged between the image forming apparatus 10 and the stapling mechanism 21 and has a punch unit 32 and a dust box 33.
The punch unit 32 is provided with a punching blade (not shown) for applying the punching processing to the sheets P. When this punching blade lowers, punch holes are opened in the sheets P. Punch dust generated by the punching processing falls into the dust box 33.
Moreover, an inserter 40 forming an essential part of the invention is provided between the image forming apparatus 10 and the finisher 20. The inserter 40 sequentially supplies sheets having images formed thereon to the finisher 20. This inserter 40 has a collating mechanism for, when plural types of sheets are inserted therein in a stacked state, sequentially delivering the sheets to the finisher 20 in a designated order. The collating mechanism will be described later.
The inserter 40 has a sheet feeding tray 41, a sheet feeding roller 42, and a back roller 43. Moreover, the inserter 40 has conveying rollers 53 and 54 for conveying the sheets P stored in the sheet feeding tray 41 to the punching mechanism 31 of the finisher 20.
Plural rollers 55 and 56 for sheet conveyance are provided on a path extending from the image forming apparatus 10 to the inlet rollers 22 of the stapling mechanism 21. The sheets P discharged from the image forming apparatus 10 are sent to the stapling mechanism 21 via the rollers 55 and 56. The sheets conveyed by the conveying rollers 53 and 54 of the inserter 40 are sent to the stapling mechanism 21 via the rollers 56.
In
The aligning plate 44 is capable of moving in a conveying direction of the sheets P (an arrow A direction). In order to move the aligning plate 44 in the arrow A direction, a rack 46 formed integrally with the sheet feeding tray 41 and a pinion 47 that meshes with this rack 46 are provided. The aligning plate 44 is moved by rotating the pinion 47 with a motor 48. A belt mechanism and the like may be used as a moving mechanism for the aligning plate 44.
The sheet feeding roller 42 and the back roller 43 are provided orthogonal to the conveying direction of the sheets P, formed in a columnar shape, and driven to rotate by motors 71 and 72 (described later with reference to
The motors 71 and 72 that rotate the sheet feeding roller 42 and the back roller 43 and moving mechanisms for the sheet feeding roller 42 and the back roller 43 are attached to a plate 49. The sheet feeding roller 42 has a function of rotating counterclockwise in the figure to discharge the sheets P from the sheet feeding tray 41. The back roller 43 has a function of rotating clockwise in the figure to retract the sheets P in a direction opposite to the sheet feeding direction.
The inserter 40 according to the invention performs a collating operation shown in
First,
The types of the sheets mean sheets having images formed thereon on the basis of different originals, respectively, and do not mean sheet sizes and materials of the sheets.
When the sheet bundle 100 is stored in the sheet feeding tray 41, the aligning plate 44 moves the sheet bundle 100 to the shutter 45 side, aligns the sheet bundle 100, and returns to the original position. The sheet feeding roller 42 moves in a direction to the sheet bundle. The back roller 43 moves to a position apart from the sheet bundle.
In this state, the shutter 45 opens and the sheet feeding roller 42 rotates in the counterclockwise direction. Consequently, a sheet A1 at the top is discharged by the sheet feeding roller 42 and guided to the rollers 53 (see
As shown in
When the sheets A2 and A3 are retracted, as shown in
Moreover, as shown in
When the sheets B2 and B3 are retracted, as shown in
Thereafter, as shown in
In this state, the shutter 45 closes and the sheet feeding roller 42 and the back roller 43 moves in the direction away from the sheet bundle 100. The motor 48 in
The sheet feeding roller 42, the back roller 43, and the shutter 45 return to the state in
The sheet B2 is discharged and the sheet B3 is retracted and then the sheet C2 is discharged and the sheet C3 is retracted. The sheets A3, B3, and C3 remain in the sheet feeding tray 41. The aligning plate 44 is moved to the shutter 45 side to align the sheets and returned to the original position.
In this state, the sheet feeding roller 42, the back roller 43, and the shutter 45 returns to the state in
The sheets discharged in the order of A1, B1, C1 . . . A3, B3, and C3 in this way are sent to the finisher 20, subjected to punching processing by the punching mechanism 31 when necessary, further subjected to staple processing by the stapling mechanism 21, and discharged to the sheet discharge tray 51.
In the example described above, the sheet bundle 100, in which the three pieces of each of the three types of sheets are stacked, is inserted in the sheet feeding tray 41. When a user operates an operation unit 70 (described later with reference to
The inserter 40 performs, on the basis of inputted information “n types and m pieces”, discharge, retraction, and alignment of sheets once, repeats the discharge, retraction, and alignment plural times, sequentially reduces the number of sheets to be retracted by one every time the discharge, retraction, and alignment is performed once, and performs only the discharge when the number of sheets to be retracted is reduced to zero.
A structure of a control system for the inserter 40 of the invention will be explained with reference to a block diagram in
In
The control unit 60 is connected to the operation unit 70 and controls operations of the inserter 40 in response to operation from the operation unit 70. The RAM 62 is used for temporarily storing control data and used in arithmetic operation work at the time of control. Operations of the counter 63 will be described later.
The operation unit 70 includes, for example, plural keys or a display unit that also functions as a touch panel. The user operates the keys or the touch panel to input the types n and the pieces m of sheets to be inserted.
The inserter 40 has the motors 71 and 72 that drive to rotate the sheet feeding roller 42 and the back roller 43. Further, the inserter 40 has driving units 73 and 74 that control to move the sheet feeding roller 42 and the back roller 43 in directions toward and away from the sheet bundle 100, respectively. The control unit 60 controls these motors 71 and 72 and the driving units 73 and 74.
The control unit 60 controls the driving of the motor 48 to control a position of the aligning plate 44 of the inserter 40. Moreover, the control unit 60 controls opening and closing operations of the shutter 45.
The control unit 60 is connected to a finisher control unit 75 that controls the finisher 20. The finisher control unit 75 controls the stapling mechanism 21 and the like of the finisher 20. The finisher control unit 75 and the control unit 60 transmit information to each other. The inserter 40 and the finisher 20 operate in cooperation with each other.
As the control of the finisher 20 by the finisher control unit 75, there are stapling by the stapler 25, conveyance of the sheets P to the stapler 25, discharge of sheets after being stapled, and the like.
Step S1 in
Step S2 is a step of aligning the sheet bundle 100 stored in the sheet feeding tray 41 with the aligning plate 44. The next step S3 is a step of discharging one sheet at the top of the sheet feeding tray 41 with the sheet feeding roller 42. The step is equivalent to
In step S4, the control unit 60 determines whether (m−1)=0. When (m−1) is not 0, in the next step S5, the control unit 60 retracts (m−1) sheets with the back roller 43. In the case of m=3, the control unit 60 retracts two sheets. This step is equivalent to
In the next step S6, the control unit 60 increments a value of the counter 63 by 1. In step S7, the control unit 60 determines whether a value of the counter 63 is n. An initial value of the counter 63 is 0 and counted up by +1 every time the operation from steps S3 to S5 is performed. Therefore, according to the loop from step S3 to step S7, the control unit 60 repeats the operation for discharging one sheet and retracting (m−1) sheets until the value of the counter 63 reaches n. This operation is equivalent to the operation from
When the value of the counter 63 reaches n in step S7, the control unit 60 shifts to step S8. The value of the counter 63 is reset and returns to 0. In the next step S9, the control unit 60 changes the value m to m−1. When an input value is 3, m is changed to 2.
In the next step S10, the control unit 60 determines whether m=0. Unless m≠0, the control unit 60 returns to step S2 and performs the alignment processing. This operation is equivalent to
In step S3, the control unit 60 discharges one sheet at the top of the sheet feeding tray 41. In step S4, the control unit 60 determines whether (m−1)=0. When (m−1) is not 0, the control unit 60 shifts to the next step S5 and retracts (m−1) sheets with the back roller 43. Since the value m is changed to 2, in step S5, the control unit retracts one sheet.
The control unit 60 repeats the operation from steps S3 to S5 (for discharging one sheet and retracting one sheet) n times. When the value of the counter 63 reaches n in step S6, the control unit 60 shifts to step S8 through step S7. The value of the counter 63 is reset and returns to 0. In the next step S9, the control unit 60 changes the value m to m−1. In this case, the value m further decreases by 1 to 1.
In the next step S10, since m≠0, the control unit 60 returns to step S2 and performs the alignment processing again. In step S3, the control unit 60 discharges one sheet at the top of the sheet feeding tray 41.
In step S4, the control unit 60 determines whether (m−1)=0. In this case, since (m−1)=0, the step S5 is detoured and the retracting processing is not performed. In this case, the control unit 60 returns to step S3 through the next steps S6 and S7 and repeats discharge of one sheet n times.
When the value of the counter reaches n in step S6, the control unit 60 shifts from step S7 to step S8. The value of the counter 63 is reset and returns to 0. In the next step S9, the control unit 60 changes the value m to m−1. Therefore, the value m changed is 0. In step S10, the control unit 60 determined that m=0, shifts to step S1, and finishes the collating processing.
In this way, in the invention, when the sheet types n and the pieces m are inputted, the inserter 40 can automatically execute the collating processing.
The invention is not limited to the above explanation. Various modifications are possible without departing from the scope of claims. For example, as the finisher 20, a saddle stitcher may be provided other than the stapling mechanism 21. The saddle stitcher is an apparatus that bundles plural sheets supplied from the image forming apparatus 10 or plural sheets collated by the inserter 40 and folds the sheet bundle in two.
Although exemplary embodiments of the present invention have been shown and described, it will be apparent to those having ordinary skill in the art that a number of changes, modifications, or alterations to the invention as described herein may be made, none of which depart from the spirit of the present invention. All such changes, modifications, and alterations should therefore be seen as within the scope of the present invention.
