Patent Application
20240425318
Embodiments described herein relate generally to a sheet processing apparatus, a sheet processing method, and an image forming apparatus.
An sheet processing apparatus includes a processing unit that processes sheets, a tray on which the sheets can be placed, and an alignment member that performs lateral alignment of the sheets placed on the tray. If the sheets are processed in a state in which the lateral alignment is incomplete, processing quality is deteriorated. There is a demand for a sheet processing apparatus that can suppress the deterioration in the processing quality.
A sheet processing apparatus in an embodiment includes a processing unit, a tray, alignment members, and a supporting member. The processing unit processes regular size sheets. The regular size sheets can be placed on a first surface of the tray. A direction in which a line of intersection of the first surface and a horizontal plane extends is represented as a first direction. A direction parallel to the first surface and perpendicular to the first direction is represented as a second direction. The regular size sheet having a largest length in the second direction among the regular size sheets to be placed on the tray is represented as a largest regular size sheet. A position in the second direction where the regular size sheet entering the tray is placed first is represented as an initial position. The alignment members are capable of coming into contact with end portions in the first direction further in an upward direction than a center of gravity of the largest regular size sheet present in the initial position. The supporting member supports a lower end portion of the largest regular size sheet and extends from inner sides to outer sides of end portions of the largest regular size sheet in the first direction.
The sheet processing apparatus in the embodiment is explained below with reference to the drawings.
The image forming apparatus main body 100 is explained.
The image forming apparatus main body 100 forms an image on a sheet (a recording medium) using a recording agent. For example, the sheet is plain paper or label paper. A specific example of the recording agent is toner. The toner is toner used as a decolorable recording agent or toner used as a non-decolorable recording agent.
For example, the image forming apparatus main body 100 is a multifunction peripheral. As illustrated in
The display unit 15 is an image display device such as a liquid crystal display or an organic EL (Electro Luminescence) display. The display unit 15 displays various kinds of information concerning the image forming apparatus main body 100 and the sheet processing apparatus 200.
The operation unit 14 includes a plurality of buttons. The operation unit 14 receives operation of a user. The operation unit 14 outputs a signal corresponding to the operation performed by the user to the first control unit 90 of the image forming apparatus main body 100. The display unit 15 and the operation unit 14 may be configured as an integral touch panel.
The image reading unit 16 reads image information of a reading target based on brightness and darkness of light. The image reading unit 16 outputs the read image information to the printer unit 17.
The sheet storing units 18 store sheets to be used for image formation. The sheet storing units 18 supply stored sheets to the printer unit 17.
The printer unit 17 forms an image on a sheet based on the image information read by the image reading unit 16 or image information received via a communication line. The printer unit 17 includes an image forming unit, a transfer unit, and a fixing device. The image forming unit forms an electrostatic latent image on a photoconductive drum based on the image information. The image forming unit causes the toner to adhere to the electrostatic latent image and forms a visible image. The transfer unit transfers the visible image onto the sheet. The fixing device heats and pressurizes the toner and fixes the visible image on the sheet.
The paper discharge roller 19 is disposed near a paper discharge port of the image forming apparatus main body 100. The paper discharge roller 19 delivers the sheet, on which the image is formed, to the sheet processing apparatus 200.
The CPU 91 executes a program stored in the memory 92 and the auxiliary storage device 93 to thereby function as the first control unit 90. The first control unit 90 controls operations of the individual units of the image forming apparatus main body 100 and the sheet processing apparatus 200.
The auxiliary storage device 93 is configured using a storage device such as a magnetic hard disk device or a semiconductor storage device. The auxiliary storage device 93 stores information.
The communication unit 94 includes a communication interface for connecting the image forming apparatus main body 100 to an external apparatus. The communication unit 94 communicates with the external apparatus via the communication interface.
The sheet processing apparatus 200 is explained.
As illustrated in
The stapling mechanism 20 includes a standby tray 21, a processing tray 22, and a stapler 23. The stapler 23 applies stapling to the peripheral edge portions of a plurality of sheets P. The stapled sheets P are conveyed by a conveyor belt 24 and discharged to a movable tray 27.
The sheet processing apparatus 200 includes the movable tray 27 and an upper tray 26. The stapled sheets P are discharged to the movable tray 27. Unstapled sheets P are discharged to the upper tray 26.
The sheet supporting unit 31 supports the sheets P. The sheet supporting unit 31 includes saddle folding trays (trays) 32, a rising and falling device 40, and alignment members 50. The sheets P can be placed on first surfaces S of the saddle folding trays 32.
As a local coordinate system of the saddle folding mechanism 30, an X direction, a Y direction, and a Z direction of an orthogonal coordinate system are defined as follows. The X direction is the normal direction of the first surfaces S of the saddle folding trays 32. A +X direction is a direction in which the sheets P are placed on the saddle folding trays 32. The Y direction (a first direction) is a direction in which a line of intersection of the first surfaces S and the horizontal plane extends. In the Y direction, a direction approaching the centers of the saddle folding trays 32 is referred to as “inner side in the Y direction”. In the Y direction, a direction away from the centers of the saddle folding trays 32 is referred to as “outer side in the Y direction”. The Z direction (a second direction) is a direction parallel to the first surfaces S and perpendicular to the Y direction. A +Z direction is a direction from the folding unit 35 toward the stapling unit 34.
The saddle folding trays 32 is substantially plate-like. The sheets P can be placed on the first surfaces S in the +X direction of the saddle folding trays 32. The saddle folding trays 32 are present on both sides in the Z direction across the folding unit 35.
The rising and falling device 40 supports the lower end portions of the sheets P placed on the saddle folding trays 32. The rising and falling device 40 rises and falls in the Z direction and moves the sheets P to the processing unit 39.
The alignment members (lateral alignment plates) 50 align (laterally align) the positions in the Y direction of the sheets P placed on the saddle folding trays 32.
The folding unit 35 is present in the center of the saddle folding mechanism 30. The folding unit 35 folds the center in the Z direction of the sheets P and creases the sheets P. The folding unit 35 includes a blade 36, a pair of folding rollers 37, and an additional folding unit 38.
The blade 36 has a flat shape and is parallel to an XY plane. The blade 36 has a shape tapered in the +X direction. The blade 36 is movable in the X direction passing through the saddle folding trays 32. The blade 36 is capable of coming into contact with the center in the Z direction of the sheets P.
The pair of folding rollers 37 is present in the +X direction of the saddle folding trays 32. The pair of folding rollers 37 is arranged in the Z direction. The pair of folding rollers 37 is long in the Y direction. Rotation axes of the pair of folding rollers 37 are parallel to the Y direction.
The additional folding unit 38 is present in the +X direction of the pair of folding rollers 37. The additional folding unit 38 additionally folds the crease of the sheets P.
The stapling unit 34 is present in the +Z direction of the folding unit 35. The stapling unit 34 applies stapling to a predetermined position of the sheets P. For example, the predetermined position of the sheets P is the center in the Z direction of the sheets P.
As illustrated in
For example, the saddle folding mechanism 30 executes bookbinding processing for a plurality of sheets P. The rising and falling device 40 rises and falls in the Z direction in a state in which the rising and falling device 40 supports the sheets P. The rising and falling device 40 places the center in the Z direction of the sheets P in the position of the stapling unit 34. The stapling unit 34 applies stapling to the plurality of sheets P. The rising and falling device 40 moves the plurality of sheets P in the −Z direction. The rising and falling device 40 places the center in the Z direction of the sheets P in the position of the folding unit 35. The blade 36 moves in the +X direction and pushes the sheets P into between the pair of folding rollers 37. The plurality of sheets P are saddle-folded in the center in the Z direction. A crease is formed in the plurality of sheets P. The additional folding unit 38 additionally folds the crease of the plurality of sheets P. Consequently, the bookbinding for the plurality of sheets P is completed. The bound plurality of sheets P are discharged to the lower tray 28.
As illustrated in
The CPU 96 executes a program stored in the memory 97 and the auxiliary storage device 98 to thereby function as the second control unit (a control unit) 95. The second control unit 95 controls operations of the individual units of the sheet processing apparatus 200. The auxiliary storage device 98 is configured using a storage device such as a magnetic hard disk device or a semiconductor storage device. The auxiliary storage device 98 stores information.
The communication unit 99 includes a communication interface for connecting the sheet processing apparatus 200 to an external apparatus. The communication unit 99 communicates with the external apparatus via the communication interface.
The rising and falling device 40 and the alignment members 50 are explained in detail.
The supporting member 45 supports the lower end portions of the sheets P placed on the saddle folding trays 32. For example, the supporting member 45 is formed by a resin material such as POM (polyacetal resin) or ABS (acrylonitrile-butadiene-styrene copolymerized resin). As illustrated in
The sheet processing apparatus 200 applies post-processing to regular size sheets of various sizes. The regular size sheets of the various sizes are placed on the saddle folding trays 32. Among the sizes of the regular size sheets, sizes of an A series such as A4 are defined in the International Standard ISO216 that defines dimensions of paper. Sizes of a B series such as B5 are defined in the ISO216 or the Japanese Industrial Standards JIS-B series. LT is a letter size and is defined as ANSI A in American Industrial Standards Association ANSI/ASME Y14.1. LG is a legal size. Among the regular size sheets placed on the saddle folding trays 32, a regular size sheet having the largest length in the Z direction is defined as a largest regular size sheet PL.
As illustrated in
As illustrated in
The alignment members 50 align the positions in the Y direction of the sheets P placed on the saddle folding trays 32. As illustrated in
The sheet processing apparatus 200 may include a longitudinal alignment member. The longitudinal alignment member pushes, in the −Z direction, the sheets P placed on the saddle folding trays 32 and aligns (longitudinally aligns) the positions in the Z direction of the sheets P. For example, the longitudinal alignment member is a paddle or a sponger roller.
As illustrated in
A standby position of the supporting member 45 of the rising and falling device 40 at the time when a regular size sheet is conveyed to the saddle folding trays 32 is different depending on the length in the Z direction of the regular size sheet. The standby position of the supporting member 45 is a position where the upper end portion of the regular size sheet is placed in the sheet upper end portion position PT. If a plurality of regular size sheets are continuously conveyed, sheet clogging is likely to occur if the leading end portion of the following regular size sheet collides with the trailing end portion of the preceding regular size sheet. The saddle folding mechanism 30 places the upper end portion of the preceding regular size sheet in the sheet upper end portion position PT and causes the leading end portion of the following regular size sheet to collide with the surface of the preceding regular size sheet. The following regular size sheet slides down on the surface of the preceding regular size sheet and is stacked in the +X direction of the preceding regular size sheet.
As explained above, the regular size sheet entering the saddle folding trays 32 comes into contact with the supporting member 45 that is staying on standby in the standby position. The regular size sheet is placed in an initial position of the first surfaces S of the saddle folding trays 32. The initial position is a position in the Z direction where the regular size sheet entering the saddle folding trays 32 is placed first.
As illustrated in
As illustrated in
If the largest regular size sheet PL is conveyed to the saddle folding trays 32, the pair of alignment members 50 is staying on standby on the outer sides in the Y direction of a conveyance region of the largest regular size sheet PL. The largest regular size sheet PL enters between the pair of alignment members 50 and is placed in the initial position in the Z direction.
The positions in the Y direction of a plurality of largest regular size sheets PL entering the saddle folding trays 32 are sometimes different from one another. The pair of alignment members 50 moves to the inner side in the Y direction and comes into contact with the end portions in the Y direction of the largest regular size sheets PL. The pair of alignment members 50 pushes the end portions in the Y direction of the largest regular size sheets PL to the inner side. The pair of alignment members 50 aligns the positions in the Y direction of the plurality of largest regular size sheets PL (causes the positions to coincide with one another).
In the sheet processing apparatus in the comparative example, it is conceivable to extend the alignment members 50 to the vicinity of the lower end portion in the Z direction of the largest regular size sheet PL. In this case, the contact positions of the alignment members 50 with the largest regular size sheet PL come closer to the end portion 79 of the supporting member 70. The turning of the largest regular size sheet PL with the end portion 79 of the supporting member 70 as the fulcrum is suppressed. However, since the alignment members 50 increase in size, it is difficult to adjust a layout of the alignment members 50 with respect to the rising and falling device 40.
In the sheet processing apparatus 200 in the embodiment illustrated in
As explained above in detail, the sheet processing apparatus 200 in the embodiment includes the processing unit 39, the saddle folding trays 32, the alignment members 50, and the supporting member 45. The processing unit 39 processes regular size sheets. The regular size sheets can be placed on the first surfaces S of the saddle folding trays 32. A direction in which a line of intersection of the first surfaces S and the horizontal plane extends is represented as a Y direction. A direction parallel to the first surfaces S and perpendicular to the Y direction is represented as a Z direction. A regular size sheet having the largest length in the Z direction among the regular size sheets placed on the saddle folding trays 32 is represented as the largest regular size sheet PL. A position in the Z direction where a regular size sheet entering the saddle folding trays 32 is placed first is represented as an initial position. The alignment members 50 are capable of coming into contact with the end portions in the Y direction further in the upward direction than the center of gravity GL of the largest regular size sheet PL present in the initial position. The supporting member 45 supports the lower end portion of the largest regular size sheet PL and extends from the inner sides to the outer sides of the end portions of the largest regular size sheet PL in the Y direction.
The alignment members 50 push portions further in the upward direction than the center of gravity GL of the largest regular size sheet PL to the inner sides in the Y direction. The end portions of the supporting member 45 are present on the outer sides of the end portions of the largest regular size sheet PL in the Y direction. The largest regular size sheet PL does not turn with the end portions of the supporting member 45 as a fulcrum. The largest regular size sheet PL moves in the Y direction along the upper surface of the supporting member 45. The plurality of largest regular size sheets PL are aligned in the Y direction. In this state, the processing of the processing unit 39 is carried out. Deterioration in the processing quality of the sheet processing apparatus 200 is suppressed.
The alignment members 50 are present further in the upward direction than the center of gravity GL of the largest regular size sheet PL present in the initial position. The alignment members 50 can be segregated from the rising and falling device 40 present further in the downward direction than the center of gravity GL of the largest regular size sheet PL. Flexibility of a layout increases. Since the alignment members 50 are reduced in size, material cost is suppressed.
The first supporting member 41 and the second supporting member 42 are disposed to be separated in the Y direction. The first supporting member 41 extends from the inner side to the outer side of the first end portion 61 of the largest regular size sheet PL in the Y direction. The second supporting member 42 extends from the inner side to the outer side of the second end portion 62 of the largest regular size sheet PL in the Y direction. One projecting section 46 extends in the +Z direction from the first supporting member 41. One projecting section 46 extends in the +Z direction from the second supporting member 42. The first supporting member 41 and the second supporting member 42 move in the Z direction in synchronization.
In the Y direction, the end portion of the first supporting member 41 and the end portion of the second supporting member 42 are present on the outer sides of both the end portions of the largest regular size sheet PL. The alignment members 50 push the largest regular size sheet PL to the inner sides in the Y direction. The largest regular size sheet PL moves in the Y direction along the upper surfaces of the first supporting member 41 and the second supporting member 42. The plurality of largest regular size sheets PL are aligned in the Y direction. Deterioration in the processing quality of the sheet processing apparatus 200 is suppressed.
The second modification is different from the embodiment explained above in that the supporting member 45 includes a low friction member 48. Explanation of the second modification concerning the same portions as the portions in the embodiment is sometimes omitted.
The supporting member 45 includes the low friction member 48 in a contact portion with the lower end portion of the largest regular size sheet PL. The low friction member 48 is disposed on the upper surface in the +Z direction of the supporting member 45. For example, the low friction member 48 is an ultra high molecular weight polyethylene tape. A coefficient of friction of the ultra high molecular weight polyethylene tape is approximately 0.06 to 0.30. A coefficient of friction of the low friction member 48 is smaller than a coefficient of friction between a pair of regular size sheets stacked on the saddle folding trays 32. The coefficient of friction of the low friction member 48 is desirably smaller than a coefficient of friction of the supporting member 45.
The lower end portion of the largest regular size sheet PL comes into contact with the low friction member 48. The alignment members 50 push the largest regular size sheet PL to the inner sides in the Y direction. The largest regular size sheet PL moves in the Y direction along the upper surface of the low friction member 48. Since the coefficient of friction of the low friction member 48 is small, the largest regular size sheet PL smoothly moves in the Y direction. Since the largest regular size sheet PL is not caught by the low friction member 48, the largest regular size sheet PL does not turn. The plurality of largest regular size sheets PL are aligned in the Y direction. Deterioration in the processing quality of the sheet processing apparatus 200 is suppressed.
According to at least one embodiment explained above, the sheet processing apparatus 200 includes the supporting member 45 extending from the inner sides to the outer sides of the end portions of the largest regular size sheet PL in the Y direction. Consequently, it is possible to suppress deterioration in the processing quality of the sheet processing apparatus 200.
While certain embodiments have been described these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms: furthermore various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and there equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the invention.
