Patent Application
20090200732
This application is based on Japanese Patent Application No. 2008-031519 filed on Feb. 13, 2008 in Japanese Patent Office, the entire content of which is hereby incorporated by reference.
The present invention relates to improvements in the sheet discharge sections of sheet finishing apparatuses and image forming apparatuses.
Image forming apparatuses such as electro-photography apparatuses are of the desktop type and the floor type.
Relatively large size image forming apparatuses such as high speed image forming apparatuses are of the floor type.
Further, sheet finishing apparatuses that are coupled to the output side of image forming apparatuses are mostly of the floor type.
Further, while there are floor type image forming apparatuses and sheet finishing apparatuses that have a plurality of sheet discharging sections, very often the apparatus configuration is such that the lower sheet discharging section among the plurality of sheet discharging sections are provided at a low position near the floor.
An image forming apparatus disclosed in Unexamined Japanese Patent Application Publication No. 2007-45620 has a first and a second sheet conveying sections that convey the discharged sheets, and a sheet finishing apparatus has been proposed in which the visual confirmation of the discharged sheets and the ease of taking them out have been improved by having a configuration of the downstream side second conveying section in which the sheet conveying surface is inclined upwards in the direction towards the downstream side.
In the Unexamined Japanese Patent Application Publication No. 2007-45620, although the sheet discharged from the sheet finishing apparatus is moved upwards by the second sheet conveying section, this is not sufficient from the point of view of universal design.
In other words, the following basic principles have been laid down in universal design:
a. Anybody can use and can obtain (equitability)
b. Anybody can use in a flexible manner (flexibility)
c. The method of use is simple (simplicity)
d. The necessary information is conveyed to the person using (perceptivity)
e. There is no severe consequence even if a mistake is made (safety)
f. Appropriate space is present when using (acquisition of space)
The proposal in Unexamined Japanese Patent Application Publication No. 2007-45620 is not satisfying these basic principles.
In particular, the basic principle of impartiality (a) is not being satisfied.
One aspect of the present invention is a sheet discharging apparatus including: a sheet discharging section that discharges sheets at a position lower than a height H0 of 381 mm from a floor surface; and a sheet stacking section, which stacks the sheets discharged from the sheet discharging section, including a sheet raising section which raises the sheets discharged from the sheet discharging section so that a position of a top part of the sheet is higher than the height H0.
While the present invention is described here based on a preferred embodiment shown in the drawings, the present invention shall not be limited to this preferred embodiment.
<Image Forming Apparatus>
The image forming apparatus main unit A shown in the figure is provided with an image reading section 1, an image processing section 2, an image writing section 3, an image forming section 4, sheet feeding cassettes 5, a sheet feeding section 6, a fixing apparatus 7, a sheet discharging section 8, and an automatic double side copying sheet feeding section (ADU) 9.
At the top part of the image forming section main unit A is placed an automatic document feeding apparatus DF. A sheet finishing apparatus FS is coupled to the image forming apparatus main unit A on the side of the left side sheet discharging section 8 shown in the figure.
A document placed on the document table of the automatic document feeding apparatus DF is conveyed in the direction of the arrow and the images on one side or both sides of the document are read out by the optical system of the image reading section 1, and is read out by the CCD image sensor 1A.
The analog signal obtained by photoelectric conversion by the CCD image sensor 1A is subjected to analog signal processing, A/D conversion, shading correction, image compression processing, etc., in the image processing section 2, after which it is sent to the image writing section 3.
During image formation, output light is emitted from the semiconductor laser of the image writing section 3, and an electrostatic latent image is formed by radiating the photoreceptor drum 4A of the image forming section 4. In the image forming section 4, the processings of charging, exposure, developing, transfer, separation, and cleaning are carried out. The recording sheet S1 conveyed from the sheet feeding cassettes 5 by the sheet conveying section 6 is made to come into close contact with the photoreceptor drum 4A on which the electrostatic latent image has been converted into a toner image by the developing operation, and the toner image is transferred by a transfer section 4B. The recording sheet S1 carrying the toner image is fixed by a fixing apparatus 7, and is sent to the sheet finishing apparatus FS from the sheet discharging section 8. In the case of double side copying, the recording sheet S1 with image formation completed on one of its sides is sent by the conveying path selection plate 8A to the automatic double side copying sheet feeding section 9, image formation is made again on the rear side by the image forming section 4, and after fixing, the recording sheet S1 is discharged from the sheet discharging section 8.
Next, the sheet finishing apparatus according to a preferred embodiment of the present invention is described using
The sheet finishing apparatus FS is provided with a sheet entering section 20, insertion sheet feeding sections 30a and 30b, and a plurality of finishing processing sections. Finishing processing sections can be a perforating section 40, a folding section 50, a stacking section 60, stitching sections 71 and 72, and a sheet discharging section 80.
Insertion sheets S2 are stacked in the insertion sheet feeding section 30a, and other insertion sheets S3 are stacked in the insertion sheet feeding section 30b.
The insertion sheets S2 and S3 are the sheets for the cover or the insert sheets that are inserted among the recording sheets S1 discharged from the image forming apparatus main unit A, and it is possible to carry out perforating operation or folding operation for these similar to the recording sheets S1.
The insertion sheets S2 and S3 fed from the insertion sheet feeding sections 30a and 30b are conveyed to the sheet entering section 20 after passing through a conveying path (without a reference symbol) that is entered from below.
The hole punching section 40 is placed in the sheet entering section 20.
Further, in the following explanations, the recording sheets S, the insertion sheets S2, and the insertion sheets S3 are collectively termed sheets S.
The folding section 50 is provided on the conveying path H1 that branches downward from the sheet entering section 20.
The stacking section 60 is placed on the downstream side of the conveying path H2 that branches upward from the sheet entering section 20, and is provided with the conveying paths H3, H4, and H5.
The stacking section 60 causes the subsequent sheets S wait in the conveying path H3 and the conveying paths H4 and H5 in order to acquire time to carry out stitching operation of leading sheets S in the stitching section 71 placed on the downstream side.
The conveying path positioned on the downstream side of the conveying path H2 branches into a conveying path that bends in a dual manner into the inside conveying path H4 and the outside conveying paths H3 and H5.
A conveying roller 21 is provided at the discharging outlet of the conveying path H4 that forms the inside curved conveying path that branches from the conveying path H2, when the first sheet that is to be stitched is conveyed to it, it accepts the leading edge of the sheet in the condition in which it has stopped rotating, and waits in the condition in which it is butting against the conveying roller 21.
As has been described above, while the sheet S that is conveyed via the conveying path H2 waits in the condition in which its leading edge is butting against the conveying roller 21, the succeeding sheets S proceed to the conveying path H3 from the conveying path H2, and arrives at the conveying roller 21.
From the conveying roller 21, two sheets are conveyed together to the accumulation section 70 in the condition in which the first sheet S and the succeeding sheet S are overlapped each other.
The conveying path H3 continues to the conveying path H2 on the downstream side of the conveying path H2, and the conveying path H5 continues to the conveying path H3.
The conveying path H3 branches into the conveying path H5 and the conveying path H6.
Next, the conveying path H6 forms the sheet discharging path that discharges the sheets S to the fixed sheet discharging tray 81.
The fixed sheet discharging tray 81 is placed at a position projecting to the outside of the sheet finishing apparatus FS on the downstream side of the conveying path H6 that branches from the stacking section 60 at the conveying roller 24 on the conveying path H3.
As was explained above, the fixed sheet discharging tray 81 accumulates the sheets S that conveyed via the conveying paths H2, H3, and H6 and are discharged.
The sheet discharging section 80 has a discharging roller 22 and an aligning mechanism, and discharges the sheets S on to a rising and falling sheet discharging tray 82. Although the aligning mechanism has not been shown in the figure, it is configured as a well-known mechanism in which reciprocating movement is made at right angles to the conveying and discharging direction in the horizontal direction thereby aligning the sheets.
The sheet discharging roller 22 is a pair of rollers which are separated from each other when the sheets are not being discharged, but contact each other at the time of discharging thereby gripping the sheets S and conveying it and discharging on to the rising and falling sheet discharging tray 82.
The sheet S conveyed by the conveying roller 21 passes between the separated pair of rollers 22 in the leftward direction, and when the trailing edge is separated from the conveying roller 21, it falls on the accumulation section 70, slides down the inclined accumulation section 70 and comes to a stop at the accumulation section by being stopped by a stopper (not shown in the figure).
When the set number of sheets S is stacked on the accumulation section 70, the stitching section 71 operates thereby stitching together the sheets S.
The stitched sheets S are pushed up by said stopper and move in the upper left direction of the accumulation section 70.
At this time, the pair of rollers constituting the sheet discharging roller 22 come into contact with each other thereby gripping the sheet S, conveying it, and discharging it on to the rising and falling sheet discharging tray 82.
In the folding mode, the sheet S is conveyed downward from the sheet entering section 20 over the conveying path H1, and in the folding section 50, the sheet is subjected to center folding or triple folding, and is then discharged on to the bottom sheet discharging section 83.
In the center stitching mode, the sheet S is conveyed downward along the conveying path H1 from the sheet entering section 20, center stitched in the stitching section 72, and is discharged to the lower sheet discharging section 83 after being center folded in the folding section 50.
The following four paths are available as the discharging paths of the sheets S.
1) Sheet entering section 20→Conveying path H2→conveying path H3→conveying path H6→fixed sheet discharging tray 81
2) Sheet entering section 20→Conveying path H2→conveying paths H3, H4, H5→accumulation section 70→sheet discharging section 80→rising and falling sheet discharging tray 81
3) Sheet entering section 20→conveying path H2→conveying path H4→sheet discharging section 80→rising and falling sheet discharging tray 82
4) Sheet entering section 20→conveying path H1→folding section 50→lower sheet discharging section 83
Paths 1), 2), and 4) are as has been described above.
Path 3) is selected when a large number of image formations are to be made without carrying out stitching and folding operations.
The sheet S is discharged to the rising and falling sheet discharging tray 82 without any finishing operation, and the rising and falling sheet discharging tray 82 moves downward as shown by the dot-and-dash lines in the figure so that the topmost surface of the discharged sheet S is always at a constant height.
Therefore, it is possible to accumulate several thousands of sheets on the rising and falling sheet discharging tray 82.
The conveying path H1 in
In the conveying path H1, a restricting member 51C has been provided that restricts the position of the sheet S in the upstream side of the folding section 50. The restricting member 51C is one that restricts the bottom edge of the sheet S to a prescribed position and can be displaced according to the size of the sheet S.
The folding section 50 has a folding plate 52, a fold up roller (hereinafter referred to as the up roller) 53, a fold down roller (hereinafter referred to as the down roller) 54, a folding roller 55, a conveying path selection member 57 functioning as the selection guiding section, a guiding member 58 functioning as the guiding section, a leading edge stopping member 581, etc., and carries out double folding or triple folding operation on the sheet S.
The up roller 53 and the down roller 54 both which constitute together a first pair of rollers that bend the sheet S by conveying and insert it between the down roller 54 and the folding roller 55.
The down roller 54 and the folding roller 55 which together constitute a second pair of rollers carry out the folding operation of the sheet S by nipping it and conveying it.
In addition, the up roller 53 and the down roller 54 carry out the folding operation during double folding, and carry out the first folding in a triple folding operation.
The down roller 54 is used commonly for conveying the sheet and the folding operation.
The up roller 53 and the down roller 54 are supported by a left and right pair of pressing means that form an almost symmetrical shape. One of the pressing means supports the up roller 53 in a rotatable manner, and is made of a supporting plate 532 that can swing around a supporting shaft 531, and a spring 533 that is connected to one end of this supporting plate 532 and biases the up roller 53 towards the gripping position. The other pressing means is made of a supporting plate 542 that can swing around a supporting shaft 541, and a spring 543 that is connected to one end of this supporting plate 542 and biases the down roller 54 towards the gripping position. The up roller 53 and the down roller 54 rotate being driven by a folding roller drive motor (not shown in the figure). The outer peripheral surfaces of the up roller 53 and the down roller 54 are formed of a material with a high friction coefficient.
The conveying path selection member 57 functioning as the selection guiding section is driven by a solenoid SD, is capable of swinging, and during the triple folding operation, gets set to the position indicated by continuous lines and guides the sheet S to the conveying path formed by the guiding member 58.
The conveying path selection member 57 is set to the position indicated by dotted lines during double folding, that is, during center folding or center stitching and center folding, and guides the sheet S to the discharging outlet E1.
The numeral 58 denotes a guiding member that functions as a guiding means that guides the sheet S between the conveying means and the leading edge stopping member 581, and forms a conveying path so that the middle part of the sheet S bends downward.
<Folding Operation>
The folding operation by the folding section 50 having the above construction is described here.
1) Triple Folding
During triple folding, the conveying path selection member 57 guides the sheet S to the conveying path formed by the guiding member 58.
The sheet S is conveyed through the conveying path H1 and stops when its leading edge buts against the restricting member 51C.
When the set number of sheets S has been restricted by the restricting member 51C and has been accumulated, the folding plate 52 is driven by the driving means (not shown in the figure) and moves in the direction of the arrow mark W1, and the folding line of the sheet S is inserted between the up roller 53 and the down roller 54.
At the same time as the movement of the folding plate 52, the up roller 53, the down roller 54, and the folding roller 55 rotate in the respective arrow mark directions, and the sheet S is conveyed while being folded.
When the sheet S is nipped between the up roller 53 and the down roller 54, the folding plate 52 recedes by moving in a direction opposite to that of the arrow mark W1.
The sheet S that is folded by the up roller 53 and the down roller 54 is conveyed with its folding line forward, and the folding line butts against the leading edge stopping member 581.
Even after the folding line has butted against the leading edge stopping member 581, the up roller 53, the down roller 54, and the folding roller 55 continue to rotate.
Due to the continued rotation of the up roller 53 and the down roller 54, the sheet S becomes curved between the nipping section between the up roller 53 and the down roller 54 and the leading edge stopping member 581.
As is shown in the figure, the guiding member 58 is formed with a shape that bends downward the sheet S that has passed the up roller 53 and the down roller 54.
Therefore, the sheet S gets bent downward.
The bent sheet S proceeds to the nipping section between the down roller 54 and the folding roller 55, and a second folding line is formed by the down roller 54 and the folding roller 55.
Because of the continued rotation of the down roller 54 and the folding roller 55, the sheet S that has been folded at two locations, that is, the triple folded sheet S is conveyed downward along the guiding member 56A, and is discharged to the lower sheet discharging section 83 from the discharging outlet E2.
2) Center Folding
During center folding (double folding), as described above, the sheet that has been folded by the folding plate 52, the up roller 53, and the down roller 54 is discharged from the upper discharging outlet E1 of the upper guiding member 56B to the lower sheet discharging section 83 by the conveying path selection member 57 set at the dotted line position.
Further, during the center stitching and center folding operation, the restricting member 51C stops the sheet S so that the center line along the conveying direction of the sheet S becomes the position of stitching by the stitching section 72.
Further, when the stitching operation by the stitching section 72 is completed, the restricting member 51C moves so that the center line of the sheet comes against the front edge of the folding plate 52.
<Sheet Discharging>
Next, the sheet discharging apparatus that discharges the sheet which has been center folded or which has been center stitched and center folded is described referring to
The sheet discharging apparatus has a folding section 50 functioning as a sheet discharging section that discharges the sheet S from the sheet finishing apparatus FS and a lower sheet discharging section 83 functioning as a sheet accumulating section.
The lower sheet discharging section 83 has a conveying belt 831 and a fixed supporting member 833, and is placed below the rising and falling sheet discharging tray 82 that has moved to the lowermost position.
The raising section that raises the sheet S that has been discharged from the sheet discharging section is constituted using a conveying belt 831 and rollers 832A and 832B.
The conveying belt 831 spans a pair of rollers 832A and 832B, and, as is shown in the figure, is placed inclined to the horizontal so that the downstream side in the conveying and sheet discharging direction is higher than the upstream side.
Even the supporting member 833 provided on the downstream side in the in the conveying and sheet discharging direction of the conveying belt 831 has a sheet supporting surface (upper surface) that is inclined to the horizontal so that the downstream side of the sheet supporting surface in the conveying and sheet discharging direction is higher than the upstream side.
The angle of inclination θ1 of the conveying belt 831 with respect to the horizontal is smaller than the angle of inclination θ2 with respect to the horizontal of the sheet supporting surface of the supporting member 833.
The conveying belt 831 circulates being driven by a motor M so that the part that supports the sheet moves towards the upper left direction in the figure.
During the execution of a job of forming images on sheets S and carrying out sheet finishing of folding the sheet S in the sheet finishing apparatus FS, the conveying belt 831 is stopped, the sheet S discharged from the folding section 50 is discharged to above the conveying belt 831, and the sheets S get accumulated on the conveying belt 831 in the order in which they are discharged.
As a method of driving the conveying belt 831, when a job is ended, apart from the method of driving the conveying belt 831, there is the method of driving intermittently during job execution, thereby moving the conveying belt intermittently by a prescribed distance thereby conveying the sheets S in the upper left direction.
The folding section 50 is placed below the accumulation section 70, the stitching sections 71 and 72, etc., so as to compress the volume of the sheet finishing apparatus FS, and in particular, to make small the width in the direction of sheet conveying.
Therefore, the sheet S that has been processed in the folding section 50 is discharged from the sheet finishing apparatus FS at a low position close to the bottom of the sheet finishing apparatus FS.
If the sheet S is discharged at a low position, the handling of the discharged sheets may become difficult, and the easiness of taking out the sheets S decreases.
This type of sheet finishing apparatus goes against the thinking of universal design (hereinafter referred to as UD) which requires that the apparatus be easy to use for any person.
An index in UD states that it should be possible to carry out various operations at a height from the floor of 381 mm or more.
The sheet discharging apparatus shown in the figure has been configured to satisfy this index.
Further, if the position of the lower sheet discharging tray 83 is made higher, since the rising and falling range of the rising and falling sheet discharge tray 82 placed above it becomes narrow, the storage capacity of the rising and falling sheet discharging tray 82 becomes small.
In the condition in which the sheet S is discharged from the folding section as is shown in
The conveying belt 831 and the supporting member 833 are formed so that at least the head part of the sheet S, that is, its topmost part is above the UDL line by raising the sheet S by conveying it using the conveying belt 831.
In specific terms, in addition to providing so that the conveying belt and the supporting member become higher in the downstream side of the conveying direction, the conveying belt 831 and the supporting member 833 are provided so that the angle of inclination θ2 of the sheet supporting surface of the supporting member 833 is larger than the angle of inclination θ1 of the conveying belt 831.
Because of such a configuration, it becomes possible to convey the sheet S higher than the UDL line without having to make long the distance of conveying by the conveying belt 831.
Further, by making θ1<θ2, the supporting member 833 will have the function of receiving the sheets, and a large number of sheets S are closely accumulated above the supporting member 833.
The height of the leading part of the sheets S conveyed by the conveying belt 831 and accumulated above the supporting member 833 differs depending on the size of the sheets, the type of folding operation, and the condition of folding of the sheets, etc.
The conveying belt 831 and the supporting member 833 are configured so that the top part of the sheets S is higher than the UDL line for all sizes of the sheets that are processed in an image forming apparatus, and also, for all types of folding operations that the folding section of the sheet finishing apparatus FS has.
The conveying belt 831 is stopped when a job is being executed.
Therefore, as is shown in
When the job ends, the conveying belt 831 circulates being driven by the motor M, a plurality of sheets S move to the upper left direction, and get accumulated above the conveying belt 831 and the supporting member 833 in an inclined accumulation condition above the supporting member 833 as is shown in
In other words, the conveying belt 831 is activated by the job end signal indicating that a series of image formations have ended thereby moving the sheets S to the upper left direction, and the conveying belt stops after the sheets S are conveyed to the state in which they are supported by the supporting member 833 as is shown in
Because of this kind of operation by the conveying belt 831, since the sheets S are accumulated above the supporting member 833 in the condition in which the sheets S are aligned, and also, since the leading part of the sheets S is positioned above the UDL line, it is possible for any operator to take out the sheets S easily.
The configuration and positioning of this type of conveying belt 831 and supporting member 833 are determined by carrying out sheet passing experiments which pass sheets S in the range of sheets that can be used in the sheet finishing apparatus FS.
The control section CR carries out the sheet discharging control described below based on the reception of the job start signal and the job end signal from the main control section MCR that carries out control of the entire image forming apparatus, and on the signal from the sheet sensor SE (see
Sheet discharge ON is the operation of starting based on the sheet detection signal of the sheet sensor SE.
In Step ST1, a judgment is made as to whether or not the job has ended, and if it has not ended (N in ST1), the sheet S that has been folded is discharged on to the conveying belt 831 and the operation of sheet discharge ends.
At the folding operation of every sheet S or every stack of sheets S, the steps ST1 and ST2 are repeated, and the sheets S are accumulated above the conveying belt 833 (the condition in
If the job has ended (Y in ST1) in the judgment in Step ST1, the motor M operates, the conveying belt 831 is driven, the accumulated sheets S are conveyed to the upper left part, and the conveying stops (ST3) in the condition shown in
In universal design stipulated concretely, for example, in the United States Rehabilitation Law No. 508, it has been made compulsory that the height above floor of control apparatuses is 15 inches (381 mm) or more.
The discharged sheets are discharged in various forms and orientations. Therefore, when this condition is applied to the sheet discharging section, various forms of the discharged sheets will have to be considered about how to guarantee the ease of handling of the discharged sheets.
In the present invention, the sheets are accumulated while raising the sheets so that at least the top part of the sheets is higher than a height of 381 mm from the floor for all types of sheets that are within the range that can be processed by the apparatus, considering that the discharged sheets are processed with raising the leading edges of the sheets and the height of the top part of the sheets changes depending on the size of the discharged sheets and the types of processing in the first sheet finishing apparatus.
Because of this, a sheet discharging apparatus is realized that conforms to the basic principles of universal design.
| Number | Date | Country | Kind |
|---|---|---|---|
| JP2008-031519 | Feb 2008 | JP | national |
