1. Field of the Invention
The present invention relates to a sheet processing apparatus which can selectively process a sheet received from a main body of an image forming apparatus and, more particularly, to a sheet processing apparatus having a plurality of stacks which stack sheets thereon.
2. Description of the Related Art
Some of conventional image forming apparatuses such as copying machines or printers are provided with a sheet processing apparatus which can sequentially receives sheets, each having an image formed thereon, and then, selectively subjects the sheets to a binding process. A sheet processing apparatus disclosed in, for example, Japanese Patent Application Laid-open No. 4-128096 is of a console type installed directly on a floor. At an upper portion of such a sheet processing apparatus are arranged a plurality of elevatable stack trays for assorting sheets. Inside of a body at a lower portion of the apparatus is housed a sheet processing portion having a stapling function in a vertical direction. A sheet received from a main body of the image forming apparatus is separately conveyed onto either one of upper and lower conveying paths by a switching member. The sheet conveyed above is separately stacked on the elevatable stack tray. In contrast, the sheet conveyed downward passes through a lower U-shaped path, on which the sheet is oriented upward at the tip thereof, and then, is conveyed onto an intermediate stack portion vertically housed inside the body of the apparatus. The sheets conveyed onto the intermediate stack portion are bound together after alignment. Thereafter, the bundle of sheets is pushed up at the rear end thereof by a belt member, to be then discharged to a discharge tray.
However, since the sheet processing portion including the intermediate stack portion in the conventional sheet processing apparatus disclosed in Japanese Patent Application Laid-open No. 4-128096 is configured in the vertical direction on an apparatus installation plane, the apparatus is increased in vertical size.
In order to miniaturize the vertical size of the sheet processing apparatus, it is construed that a distance between the intermediate stack portion and the stack tray disposed above the intermediate stack portion is reduced as possible. However, since the intermediate stack portion is configured in the vertical direction, as described above, the mere reduction of the distance causes the tip of the sheet to enter under the upper stack tray when the sheet is discharged from the intermediate stack portion, thereby raising an accident of jamming. In view of this, it is necessary to form a clearance between the intermediate stack portion and the upper stack tray enough to prevent the sheet from being jammed, thereby making it difficult to miniaturize the apparatus.
Furthermore, in order to miniaturize the vertical size of the sheet processing apparatus, it is construed that the intermediate stack portion is disposed in a lateral direction along the upper stack tray. However, a mere proximity between the intermediate stack portion and the upper stack tray possibly causes an accidental touch to the sheet being aligning on the intermediate stack portion or erroneous withdrawal of the sheet when a user accesses the sheet on the stack tray.
In view of the above, an object of the present invention is to provide a sheet processing apparatus in which an erroneous access to a sheet on an intermediate stack portion as a first stack portion can be reduced while the apparatus can be miniaturized.
In order to achieve the above-described object, a sheet processing apparatus according to the present invention comprises: a first stack portion which stacks thereon a conveyed sheet with one end of the sheet abutting against a first abutment reference; and a second stack portion which is disposed right above the first stack portion in a vertical direction and stacks a conveyed sheet thereon with one end of the sheet abutting against a second abutment reference, wherein the first abutment reference is disposed such that the first abutment reference project from a vertical line passed through the second abutment reference.
And in order to achieve the above-described object, a sheet processing apparatus according to the present invention comprises: a first stack portion which stacks thereon a conveyed sheet; and a second stack portion which is disposed right above the first stack portion in a vertical direction and stacks the conveyed sheet thereon, the second stack portion having such a length that an end of the sheet having a maximum length to be stacked on the first stack portion downstream in the sheet conveyance direction cannot project from a vertical line passed through an end of the second stack portion downstream in the sheet conveyance direction.
According to the present invention, the first stack portion and the second stack portion can be disposed in the proximity of each other, thus achieving the miniaturization of the apparatus. Furthermore, the sheet of a maximum length stacked on the first stack portion can be concealed from the second stack portion, as viewed from above in the vertical direction, even if the length of the second stack portion in the sheet conveyance direction cannot be made greater than necessary. Thus, it is possible to reduce an erroneous access to the sheet stacked on the first stack portion while achieving the miniaturization of the apparatus.
Further features of the present invention will become apparent from the following description of exemplary embodiments (with reference to the attached drawings).
Detailed descriptions will be illustratively given below of preferred embodiments according to the present invention in reference to the attached drawings. Incidentally, it is to be understood that the dimensions, materials and shapes of constituent parts described below in the preferred embodiments and relative arrangements therebetween should be appropriately varied according to configurations of apparatuses, to which the present invention is applied, or various conditions. As a consequence, the scope of the present invention is not limited to those in the embodiments, unless otherwise stated in particular.
First of all, a schematic configuration of an image forming apparatus provided with a sheet processing apparatus in a first embodiment will be described below in reference to
As shown in
The image forming portion 2 conveys a plurality of sheets S stacked on a sheet cassette 4 one by one in separation by means of a sheet roller 6 and separating/conveying rollers 7, and then, conveys them to an image forming process unit (i.e., a process cartridge) 9 through a conveying guide 8, as shown in
The image forming process unit 9 is adapted to form an image (i.e., a toner image) by an electrophotographic system. Specifically, a charged photosensitive drum 10 serving as an image bearing member is illuminated with light by a laser scanner 11, and then, the image is developed with a toner, so that the resultant toner image is transferred onto the sheet S.
The sheet S having the toner image transferred from the photosensitive drum 10 is conveyed to a fixing unit 12, which fixes the image by the application of heat and pressure.
The sheet S having the image fixed thereto is switchably conveyed onto a face-up conveying path 14 or a switch-back conveying path 15, which reverses the sheet upside down, by a conveying path switching member 13.
The sheet conveyed onto the switch-back conveying path 15 is conveyed by switch-back conveying rollers 16 until the rear end of the sheet passes a switching member 17. Thereafter, the sheet is conveyed in a vertically reverse state in which the rear end heretofore serves as a fore end by the effect of the reverse of the switch-back conveying rollers 16. At this time, the reversed sheet is conveyed onto a face-down conveying path 18 by the switch of the switching member 17.
The face-up conveying path 14 and the face-down conveying path 18 are converged before discharge rollers 19. Both of the sheet guided on the face-up conveying path 14 and the sheet passing the face-down conveying path 18 from the switch-back conveying path 15 are discharged from the image forming portion 2 by the discharge rollers 19.
The image reading portion 3 includes a scanner unit 21 and an automatic document feeder (hereinafter abbreviated as “an ADF”) 22, as shown in
The scanner unit 21 is provided with the movable optical carriage 27, to read the information described on the document. The scanner unit 21 reads the information described on the document while the optical carriage 27 scans the document placed on the document base plate glass 26 in a horizontal direction, and then, optoelectronically transduces the information by a CCD 28. In addition, when is read the document in the above-described ADF 22, the optical carriage 27 stationary at the document reading position 25 reads the information described on the document being conveyed, as described above.
Subsequently, the sheet processing apparatus 1 will be described below in reference to
The intermediate stack portion 34 is adapted to temporarily stack thereon the sheet from the main body A of the image forming apparatus. As shown in
The lower stack tray 35 is disposed under the intermediate stack portion 34, and serves as a third stack portion, on which the sheet falls down from the jogger 51 or 52 in the intermediate stack portion 34.
The upper stack trays 44 and 45 serve as a second stack portion, on which the sheet received from the main body A of the image forming apparatus is directly stacked. As shown in
As shown in
First, explanation will be made on the case where the sheet is conveyed onto the stapling conveying path 42 by switching the switching member 41. The intermediate stack portion 34 for temporarily stacking the sheet thereon is located downstream of an intermediate conveying roller 31. Downstream of the intermediate stack portion 34 are disposed the joggers 51 and 52 for jogging the sheet in a direction perpendicular to the sheet conveyance direction and a drive 53 for driving the joggers 51 and 52. During the sheet alignment, an upper discharge roller 32 out of a pair of discharge rollers 32 and 33 is retreated upward in such a manner as not to interfere with the alignment. When the rear end of the sheet passes the intermediate conveying roller 31, the sheet is landed on the intermediate stack portion 34, to be then moved in a width direction perpendicular to the sheet conveyance direction by the joggers 51 and 52, and thus, is aligned in the width direction. Thereafter, the end of the sheet abuts against the alignment reference wall 34a by an aligning roller 36, so that the sheet is aligned in the sheet conveyance direction. This operation is repeated every time one piece of sheet is conveyed. When the last sheet is conveyed and aligned, the bundle of sheets is stapled at the upstream end thereof by a stapler 54. Thereafter, the bundle of sheets is discharged onto the stack tray 35 by the pair of discharge rollers 32 and 33. Moreover, the sheet conveyed onto the stapling conveying path 42 is discharged as it is onto the stack tray 35 by the pair of discharge rollers 32 and 33 without any aligning in a non-stapling mode.
Referring to
Next, explanation will be made on the case where the switching member 41 is switched, and the sheet is conveyed onto the assorting conveying path 43. As shown in
Subsequently, the relationship between the intermediate stack portion 34 and the stack tray 44 disposed above the intermediate stack portion 34 will be described in reference to
As shown in
As shown in
In the meantime, the sheet already discharged on the stack tray 44 by the pair of discharge rollers 38 slides down upstream on the stack tray 44 by gravity, to thus abut against the stack reference wall 44a, as shown in
Moreover, a cutout 61 is formed at the stack tray 44 downstream in the sheet conveyance direction, to take out the stacked sheet S, as shown in
Incidentally, although the minimum length is the LTR size whereas the maximum length is the LGL size in the above description, the present invention can be applied to apparatuses for sheets having sizes other than the exemplified sizes by setting each of the values in such a manner as to satisfy the relationship represented by the above-described equation. In the example with the above-described sheet sizes, the grasp margin Y is 20 mm and the distance X is 100 mm.
Here, an angle θ1 with respect to the installation surface of the intermediate stack portion 34 is set within a range from about 15° to 40° inclusive of the joggers 51 and 52. In addition, an angle θ2 with respect to the installation surface of the stack tray 44 is set at about 30°. The relationship between these two angles is expressed by an angular difference, such that the intermediate stack portion 34 and the stack tray 44 are defined to be substantially parallel to each other within a range of 20° or less.
Although the description has been given of the relationship between the intermediate stack portion 34 and the stack tray 44 disposed above the intermediate stack portion 34 is expressed by a single step, it is not limited to this. In other words, there may be a plurality of steps.
As described above, the intermediate stack portion 34 and the stack tray 44 disposed above the intermediate stack portion 34 can be arranged in the proximity of each other by disposing the intermediate stack portion 34 and the stack tray 44 disposed right above the intermediate stack portion 34 at the installation surfaces thereof parallel to each other, thus achieving the miniaturization of the apparatus. Additionally, even if the stack tray 44 disposed above the intermediate stack portion 34 is short in the sheet conveyance direction, the sheet having the maximum length held by the intermediate stack portion 34 and the joggers 51 and 52 can be concealed from the stack tray 44 disposed above the intermediate stack portion 34, as viewed from above in the vertical direction. As a consequence, it is possible to reduce an erroneous access to the sheet on the intermediate stack portion while achieving the miniaturization of the apparatus.
Additionally, the stack tray 44 disposed above the intermediate stack portion 34 also serves as a cover for concealing the intermediate stack portion 34 inclusive of the joggers 51 and 52 disposed downward. Thus, the intermediate stack portion 34 and the stack tray 44 disposed above the intermediate stack portion 34 can be arranged more in the proximity of each other in comparison with a configuration in which a cover is independently disposed in the intermediate stack portion, and further, a cost of a cover can be reduced.
Subsequently, a description will be given below of a second embodiment in reference to
In the present preferred embodiment, as shown in
The cover member 63 stays at the downward position 63a in a natural state by its own weight. That is to say, the downward position 63a is regarded as a home position of the cover member 63 at the time of the turning-on of a power source or during stand-by for a job. The cover member 63 covers the tip of the sheet S held on the intermediate stack portion 34 and the joggers 51 and 52 at the home position. In other words, the cover member 63 blocks a hand of a user in such a manner as to prevent any touch to the sheet being processed on the intermediate stack portion 34 and the joggers 51 and 52 when the sheet is taken out of the stack tray 44, as shown in
Furthermore, since the cover member 63 is light in weight, it can be rotated by a very small force. As a consequence, when the sheet is discharged from, dropped from or stacked on the intermediate stack portion 34 and the joggers 51 and 52, the sheet to be discharged pushes the cover member 63 up to the parallel position 63b, to be thus discharged.
As described above, the rotatable cover member 63 is disposed in the cutout 61 formed in the stack tray 44 disposed above, so as to cover the tip of the sheet S held on the intermediate stack portion 34 and the joggers 51 and 52, thus preventing any touch of the hand of the user to the sheet being processed. Moreover, when the sheet on the intermediate stack portion 34 is discharged, the cover member 63 cannot interfere with the discharge since the cover member 63 can be readily rotated in a discharge direction by the sheet to be discharged.
Subsequently, a description will be given below of a third embodiment in reference to
In the present preferred embodiment, as shown in
Upon the pushing-down of the auxiliary tray 65 when the user takes out the sheet, as shown in
Since the intermediate stack portion 34 inclusive of the joggers 51 and 52 is located in the proximity of the auxiliary tray 65, the rotational angle of the auxiliary tray 65 is made small. A stack surface of the auxiliary tray 65 is formed from downstream to upstream in the sheet conveyance direction astride the rotational fulcrum 66, and further, a tray end 65c at a portion upstream of the rotational fulcrum 66 is formed upstream beyond downstream at the end of the sheet S on the tray 65, as shown in
Moreover, a reverse surface 65d of the auxiliary tray 65 is not uneven but smooth in the sheet conveyance direction in such a manner that the sheet S being processed touches on the intermediate stack portion 34 and the joggers 51 and 52. As a consequence, even in the case where the sheet is taken out of the stack tray 44 during the discharge or fall after the sheet is processed, no sheet is jammed on the intermediate stack portion 34.
As described above, the auxiliary tray 65 covers the sheet S on the intermediate stack portion 34 when the sheet is taken out of the stack tray 44 disposed above, thereby more preventing any touch on the sheet S on the intermediate stack portion 34. In addition, the end of the stacked sheet can be lifted up by rotating the auxiliary tray 65, so that the sheet taking-out property can be maintained even with the small rotating amount. Additionally, the tip of the auxiliary tray 65 can be more suppressed from projecting toward the reverse surface of the stack tray 44 in comparison with the above-described second embodiment. The stack tray 44 disposed above can be located in the proximity of the intermediate stack portion 34 inclusive of the joggers 51 and 52, thus more miniaturizing the apparatus.
Although the above-described embodiments have been configured such that the stack tray 44 disposed above the intermediate stack portion 34 has the constant length in the sheet conveyance direction, the present invention is not limited to this. For example, the stack tray 44 disposed above the intermediate stack portion 34 may be configured such that the sheet stack surface includes an extending member 44a extensile downstream in the sheet conveyance direction. In this case, the extending member can extend up to a position at which the end of the sheet stacked on the intermediate stack portion 34 downstream in the sheet conveyance direction does not project, as viewed from above in the vertical direction. In other word, an end of the sheet, downstream in the sheet conveying direction, having a maximum length to be stacked on the intermediate stack portion 34 cannot project from a vertical line passed through an end of the extending member. With this configuration, the length of the stack tray 44 disposed above can be varied according to the length of the sheet stacked on the intermediate stack portion 34. Therefore, for the user who uses only a sheet of a small size, the apparatus can be miniaturized by putting away the extending member.
Moreover, although the above-described embodiments have been configured such that the two stack trays serve as the second stack portion which is disposed above the intermediate stack portion and stacks the sheet thereon, the present invention is not limited to this. The stack may be at least one: otherwise, it may be one or three or more.
Additionally, although the image forming apparatus has been exemplified by the copying machine in the above-described embodiments, the present invention is not limited to this. For example, the image forming apparatus may be other types of image forming apparatuses such as a scanner, a printer and a facsimile, or a composite machine configured by combining them with each other. The same effects can be produced by applying the present invention to sheet processing apparatuses for use in the image forming apparatuses.
In addition, although the sheet processing apparatus detachably attached to the image forming apparatus has been illustrated in the above-described embodiments, the present invention is not limited to this. For example, the image forming apparatus may integrally include a sheet processing apparatus. The same effects can be produced by applying the present invention to the sheet processing apparatus.
While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
This application claims the benefit of Japanese Patent Applications No. 2007-015798, filed Jan. 26, 2007, No. 2008-008741, filed Jan. 18, 2008 which are hereby incorporated by reference herein in their entirety.
Number | Date | Country | Kind |
---|---|---|---|
2007-015798 | Jan 2007 | JP | national |
2008-008741 | Jan 2008 | JP | national |
This application is a continuation of U.S. patent application Ser. No. 12/017,732, filed Jan. 22, 2008, now U.S. Pat. No. 7,753,368 and allowed Mar. 9, 2010.
Number | Name | Date | Kind |
---|---|---|---|
5255902 | Coombs | Oct 1993 | A |
5443249 | Rizzolo et al. | Aug 1995 | A |
5552875 | Sagiv et al. | Sep 1996 | A |
5909871 | Takehara | Jun 1999 | A |
5931460 | Kadowaki et al. | Aug 1999 | A |
5963754 | Itoh et al. | Oct 1999 | A |
6042098 | Kubota et al. | Mar 2000 | A |
6142461 | Asao et al. | Nov 2000 | A |
6290220 | Takehara et al. | Sep 2001 | B1 |
6318718 | Ogata et al. | Nov 2001 | B1 |
6325371 | Araki et al. | Dec 2001 | B1 |
6382616 | Waragai et al. | May 2002 | B1 |
6398203 | Saito et al. | Jun 2002 | B1 |
6450492 | Coombs et al. | Sep 2002 | B1 |
6561503 | Ogata et al. | May 2003 | B1 |
6661995 | Isobe et al. | Dec 2003 | B2 |
6733007 | Sekiyama et al. | May 2004 | B2 |
6973285 | Sekiyama et al. | Dec 2005 | B2 |
6997456 | Fukatsu et al. | Feb 2006 | B2 |
7121541 | Saito et al. | Oct 2006 | B2 |
7258339 | Fukatsu et al. | Aug 2007 | B2 |
20050189690 | Kuwata et al. | Sep 2005 | A1 |
Number | Date | Country |
---|---|---|
59-228668 | Dec 1984 | JP |
4-128096 | Apr 1992 | JP |
10-194554 | Jul 1998 | JP |
2001-058756 | Mar 2001 | JP |
2005-280856 | Oct 2005 | JP |
Entry |
---|
Japanese Office Action, dated May 8, 2012, issued by the Japanese Patent Office, in Japanese Patent Application No. 2008-008741. |
Number | Date | Country | |
---|---|---|---|
20100264581 A1 | Oct 2010 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 12017732 | Jan 2008 | US |
Child | 12795043 | US |