JP2000038227A - Sheet support device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately and surely position and align tips of sheets without depending on the number of stacked sheet, prevent the deformation of a sheet to be discharged, and dispense with an extra force at the time of sheet discharge. SOLUTION: When a sheet 51 is supplied on a support member 3 to form a stacked condition of the sheets 51, a curve which does not go upward on the sheet tip side but faces upward is given to a rear end side part of the stacked sheet by a curve formation means 2d by utilizing the weight of the stacked sheet so that a curve effective for the sheet stack can be formed irrespective of the number of sheets. A tip of the sheet stack is brought into contact with a contact member 2e to align the tips thereof accurately and surely. On the other hand, when this sheet stack is held, the curve is removed from the sheet stack by a curve removing means 6a so that the sheets stacked by aligning tips accurately and surely can be held and discharged in a horizontal condition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet supporting apparatus for supporting a sheet deposit formed by depositing recording sheets such as printing paper, and more particularly to an image forming apparatus such as a printing machine and a copying machine. The present invention relates to a seat supporting device to be used.

[0002]

2. Description of the Related Art For example, in an image forming apparatus such as a printing machine or a copying machine, a recording sheet such as printing paper is deposited (laminated) on a sheet supporting device, and a sheet of a sheet deposit formed by depositing the sheet is deposited. For example, the sheet is discharged to the image forming unit one by one by driving a sheet feeding unit such as a pickup roller (the sheet is fed) to form an image on the sheet.

[0003] At this time, if the leading end position (edge position on the sheet supply side) of the sheets deposited on the sheet supporting device is shifted, the image forming position of the discharged sheet by the image forming unit is shifted. In the sheet supporting apparatus, the position of the leading edge of the stacked sheets is determined, and the leading edge is aligned and held.

Specifically, when a sheet is deposited, a constant urging force is applied to the sheet deposit by an urging means, and the leading end of the sheet is brought into contact with a positioning means to perform positioning and align the leading ends. Adopted.

[0005] By adopting such a configuration, the sheet is always stacked and held with its leading edge aligned. For example, even if the sheet supporting device is moved for replenishing the sheet, the sheet is held by the urging means. The stacking state of the sheet is not changed by the influence.

As a sheet supporting apparatus having such an urging means, for example, Japanese Unexamined Utility Model Publication No. 1-129171, Japanese Unexamined Utility Model Publication No. 2-149637, and Japanese Unexamined Patent Publication No. 2-295822
An apparatus described in Japanese Patent Application Laid-Open Publication No. H10-209400 is known.

Japanese Utility Model Laid-Open No. 1-129171, Japanese Utility Model Laid-Open No. 2
In the apparatus described in JP-A-149637, the rear side of the stacked sheet is directed upward (diagonally upward) by a biasing means which is located at the rear side of the stacked sheet and has an inclined shape or a curved shape. By biasing (toward) and bending the tip, the tip comes into contact with the positioning means to perform positioning and align the tips.

Further, the apparatus described in Japanese Patent Application Laid-Open No. 2-295822 adopts a structure in which a sheet is urged by inclining the entire stacked sheet.

[0009]

However, Japanese Utility Model Laid-Open No. 1-129171 and Japanese Utility Model Laid-Open No. 2-149637.
In the apparatus described in Japanese Patent Application Laid-Open Publication No. H10-260, since the rear side of the sheet is curved by the urging means, the force for discharging the sheet while bending the sheet is smaller than when discharging the sheet in a horizontal state. There was a problem that extra was required.

Also, since the sheet is always in a curved state,
If this curving state continues for a long time, the curling of the sheet will occur, which causes problems such as jamming of the sheet and failure to form an image on the sheet.

Further, in the upward biasing by the biasing means having an inclined shape or a curved shape, if the number of sheets is increased and the deposition thickness is increased, the entire sheet cannot be formed with a good curvature. There is also a problem that positioning cannot be performed accurately.

In the apparatus described in Japanese Patent Application Laid-Open No. 2-295822, it becomes more difficult to bias and hold the entire sheet by inclining as the number of sheets increases and the stacking height increases. There is a problem. Further, it is necessary to design in consideration of the relationship between the inclination angle, the sheet discharge direction, and the position of the leading edge of the sheet, and thus there is a problem that the design becomes complicated.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and when forming a stacked state of sheets, the sheet is favorably curved without being influenced by the number of sheets to be stacked. While the leading edge of the sheet can be accurately and reliably positioned and aligned, the deposited sheet can be held and discharged in a horizontal state with the leading edge accurately and reliably aligned, and deformation of the discharged sheet can be prevented. And prevent unnecessary extra force when discharging the sheet.
It is another object of the present invention to provide a seat supporting device capable of eliminating a complicated design.

[0014]

SUMMARY OF THE INVENTION A sheet supporting apparatus according to the present invention comprises a supporting member for supporting a lower surface of a sheet deposit formed by depositing recording sheets, and a sheet depositing device for depositing the sheet deposit on the supporting member. An abutting member that contacts the sheet supply side edge to determine the position of the edge, and a position where the sheet is supplied on the support member to form a stacking state of the sheet and the sheet stacking state is formed. A sheet support device in which at least the support member is movable between a position where the deposited sheet deposit is held and a portion opposite to the sheet supply side of the sheet deposit deposited on the support member, A curving unit configured to support the sheet deposit from above and provide an upward curving to the sheet deposit; and a curving unit for removing the curving of the sheet deposit provided by the curving unit. When a sheet is replenished thereon to form a stacking state of the sheet, the curve forming means acts to give a curve to the sheet stack, and at least holds the sheet stack in which the sheet stacking state is formed. When you keep
It is characterized in that the curvature removing means acts to remove the curvature from the sheet deposit.

According to the sheet supporting apparatus of the present invention, when a sheet is supplied onto the supporting member to form a stacked state of the sheet, the sheet forming side of the sheet deposit is formed by the curve forming means. On the opposite side of the sheet stack, regardless of the number of sheets (even if the number of sheets increases), an upward curving is given by using the weight of the sheet stack instead of going upwards on the sheet supply side. Is formed, the edge of the sheet deposit on the sheet supply side abuts on the abutting member, and the edge is accurately positioned and aligned. In this curved state, even if an external force such as vibration acts on the support member, the sheet deposit does not collapse, so that the positioning of the edge is reliably maintained. Further, when the sheet deposit in which the sheet deposition state is formed is held, the curving is removed from the sheet deposit by the curving removing means, so that the sheet supply side edges are accurately and reliably aligned. Holding the deposited sheet pile in a horizontal position,
Discharge is enabled, deformation of the discharged sheet is prevented (there is no tendency to bend due to bending), and unnecessary force at the time of discharging the sheet is unnecessary. Further, since the configuration is such that the entire sheet is not biased and held while being inclined, a complicated design is not required.

Here, the portion of the sheet deposit that is curved by the curve forming means on the side opposite to the sheet supply side is:
More specifically, the position is closer to the opposite edge than the intermediate position between the edge on the sheet supply side and the edge on the opposite side.

Since such a curve is formed in an area less than half of the sheet area, the force required for the curve is
It is much less than when the entire sheet is curved. Further, since the buckling deformation of the sheet deposit also occurs only on the opposite edge side of the sheet deposit, even if the deposit height of the sheet deposit is high due to a large number of sheets to be deposited, Curving is effectively formed and positioning is performed.

More specifically, the uppermost sheet of the sheet deposit is a sheet discharged for recording from the supply side edge in a state where the curving is removed by the curving removing means.

As described above, since the sheet at the uppermost position of the sheet deposit is discharged after the curving is removed,
Separated and discharged better than the above positioning position.

It is preferable that the bending means is constituted by a plurality of push-up members which form a curve by pressing the sheet at the lowest position of the sheet deposit and pushing up the sheet at the lowest position. .

When such a configuration is employed, the curvature of the entire sheet deposit can be controlled with a simple configuration.
The cost can be reduced.

The push-up member is fixed to a base located below the support member, and the support member supporting the sheet deposit moves downward to press the lowermost sheet. Adopted.

When such a configuration is adopted, since the sheet deposit is curved by the downward movement of the support member, the force for producing the curve is the same as that described above. The weight of the object is utilized and this force increases in proportion to the thickness of the sheet pile. For this reason, even if the thickness of the sheet deposit is large, the curve is efficiently formed.

Further, the curving removing means may be constituted by a driving means for moving the supporting member in a direction perpendicular to the sheet surface after the curving is removed so as to cancel the pressing of the lowermost sheet by the push-up member. It is preferable to employ it.

When such a configuration is adopted, when eliminating the curvature of the sheet deposit, the pressing force acting on the sheet without generating a force parallel to the sheet surface is reduced by the curvature removing means. As a result, the state is shifted to a state in which the sheet deposit is stably held without causing a deviation in the sheet.

Further, it is preferable that the driving means also serves as a driving means for moving the sheet deposit until it reaches the position where the uppermost sheet is discharged for recording.

In the case where such a configuration is adopted, since the bending removing means and the driving means are shared, the configuration is further simplified.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a seat supporting device according to the present invention will be described below with reference to the accompanying drawings. In each of the drawings, the same elements are denoted by the same reference numerals, and redundant description will be omitted.

FIG. 1 is a schematic configuration diagram showing a stencil printing machine 50 to which the sheet supporting device 1 according to the first embodiment is applied.

As shown in FIG. 1, the stencil printing machine 50 has a plate cylinder 54a, an impression cylinder 54b, etc., and performs printing on recording sheets (printing paper in this case) 51, 52c which are conveyed. And a discharge unit 55 that stacks and holds the sheets printed by the printing unit 54 so that they can be separated and taken out.

The stencil printing machine 50 further includes a sheet support device 1 (details will be described later) of the present invention for holding the sheet 51 before printing so as to be able to be supplied to the printing unit 54, and an upper portion of the sheet support device 1. And a second sheet supporting device 52 for holding a sheet 52c of a smaller size than the sheet supporting device 1 so as to be able to be supplied to the printing unit 54, and a second sheet supporting device 52 arranged adjacent to the second sheet supporting device 52. , Sheet 5
And a third sheet support device 53 for holding the second sheet support 3b in the second sheet support device 52 so as to be replenishable.

The stencil printing machine 50 further includes a scanner section 56 for reading data to be printed, and a printing cylinder 54 based on the data read by the scanner section 56.
a stencil making section 57 for making a stencil sheet wound around the stencil a, and a stencil making section 58 for stencil sheet stencil sheet which becomes unnecessary after printing is completed
And

The second sheet support device 52 is provided with a base 52i which is detachable from the stencil printing machine 50 by sliding in the front-rear direction (direction perpendicular to the paper surface) of the stencil printing machine 50. , Fixed to the frame of the stencil printing machine 50,
Guide members 52g and 52h that support both ends (right and left ends in the drawing) of the base 52i in a direction orthogonal to the front-rear direction and guide the base 52i so as to be slidable in the front-rear direction; An A4 size sheet 52c is placed, and a swing table 52a is installed so as to be able to swing vertically about the third sheet support device 53 side (left side in the figure). A compression coil spring 52b for urging the sheet supply side (right side in the figure) upward.

The third sheet supporting device 53 is also
It is arranged on the base 52i, and is arranged adjacent to the second sheet support device 52 on the side opposite to the sheet supply side (left side in the figure). The third sheet support device 53 is
And a supply table 53a on which a sheet 53b of the same size as the sheet 52c of the sheet support device 52 is placed.
Move from the side opposite to the sheet supply side to the sheet supply side (from left to right in the figure), and
The moving member 53d, which moves and replenishes the sheet 53b to the swing table 52a by pressing the rear end of the sheet 52c, supports the sheet 52c by abutting the rear end of the sheet 52c of the second sheet supporting device 52. And a support plate 53c that is opened when all of the sheets 52c are discharged and replenished with a new sheet 53b, and that enables the sheet 53b to be moved to the second sheet support device 52.

The uppermost sheet of the sheet 52c urged upward by the compression coil spring 52b abuts above the sheet supply side of the second sheet support device 52, and discharges the uppermost sheet. A discharge roller (also referred to as a pickup roller) 52d is provided.

A pair of registration rollers 52e for adjusting the discharge timing of the uppermost sheet of the second sheet supporting device 52 discharged by the discharge roller 52d to the printing section 54 is provided downstream of the discharge roller 52d. A guide path 52f for guiding the sheet to the printing unit 54 is provided downstream of the registration roller pair 52e.

Next, a description will be given of the sheet supporting apparatus 1 which is a feature of the present embodiment. As shown in FIGS. 1 and 2, the sheet support device 1 includes a base 2 which is detachably mounted on the stencil printing machine 50 by sliding in the front-rear direction of the stencil printing machine 50. Guide members 51c, 51d fixed to a frame of the machine 50, supporting both ends 2a, 2b of the base 2 in a direction orthogonal to the front-rear direction, and slidably guiding the base 2 in the front-rear direction. Placed on top,
A mounting table (supporting member) 3 on which an A3-size sheet 51 is mounted and which is vertically movable.

As shown in FIG. 2, the mounting table 3 has a substantially rectangular flat plate shape for depositing and supporting the sheet 51.
The mounting table 3 has pins 3a and 3b on its front side (front side in the figure) and pins 3c and 3d (only 3d not shown) on its rear side (back side in the figure). It is protruding. One end of a rope 4a, 4b, 4c, 4d is connected to each of the pins 3a, 3b, 3c, 3d, and the other end of each of the ropes 4a, 4b, 4c, 4d is a pulley 5a, After passing through 5b, 5c, 5d respectively, the rope 4a,
4b is a pulley 6a, and ropes 4c and 4d are a pulley 6b.
, And each is wound up. Although not shown, the pulleys 5a to 5d are rotatably supported by the base 2.

The pulleys 6a and 6b are rotated by driving means such as a motor (not shown; curving removing means), and take up or unwind the ropes 4a to 4d evenly. The table 3 moves up and down in a horizontal state.

At this time, on the mounting table 3, the sheet stacking state forming position A (the position shown in FIG. 1) when the sheet 51 is supplied and the stacking state of the sheet 51 is formed, and this sheet stacking state is formed. The sheet holding position B (the position shown in FIG. 4) for holding the sheet deposit (the one on which the sheet 51 is deposited) and the sheet discharging position C (FIG. 5) for discharging the uppermost sheet of the sheet deposit (Positions shown in (1) and (2)) by vertical movement (details will be described later).

As shown in FIG. 2, on the opposite side (upper left side in FIG. 2) of the mounting table 3 from the sheet supply side, along the width direction (the direction perpendicular to the plane of FIG. 1). A plurality of holes 3f are opened. When the mounting table 3 is at the lowermost position of the sheet stacking state forming position A, as shown in FIGS. 2 and 3, the push-up members (curve forming means) 2d protrude from the respective holes 3f.

The push-up members 2d are connected to the base 2
As shown in FIG. 3, the leading end (upper end) of the sheet supply side (the right side in FIG. 3) is rounded so that the sheet 51 is not caught and can form a good curve.
It is shaped.

As shown in FIG. 2, cutouts 3e and 3g are formed on both sides of the mounting table 3 in the width direction, respectively, and correspond to the cutouts 3e and 3g of the base 2. The cutouts 2c and 2g are also formed at the positions indicated by). A regulating member 7a is loosely fitted in one notch pair 2c, 3e, and a regulating member 7b is loosely fitted in the other notch pair 2g, 3g. These regulating members 7a, 7b are, for example, cylinders or the like. The actuator (not shown) is configured to move in the notch along the width direction. Then, by the movement of the regulating members 7a, 7b, the side surface of the sheet 51 deposited on the mounting table 3 is moved by the regulating members 7a, 7b.
The sheet 51 is positioned in the width direction between the sheets b.

Further, the sheet supply side end surface of the mounting table 3
As shown in FIGS. 2 and 3, the contact member 2e having a flat plate shape
Is located. The abutting member 2e is protruded from the base 2, and its tip has a shape inclined toward the sheet discharge downstream side (upper right side in FIG. 3) in order to discharge the sheet 51 smoothly. I have. The height of the contact member 2e is
The setting is made in consideration of the stacking height of the sheet 51.

The contact member 2e and the push-up member 2
In the base 2 having d, both ends in the longitudinal direction (horizontal direction in FIG. 3) orthogonal to the width direction each form an angle shape, and these ends 2a and 2b are arranged as shown in FIG. , Guide member 5 fixed to the frame of stencil printing machine 50
It is slidably guided by 1c and 51d.

That is, the sheet supporting device 1 can be put in and taken out of the stencil printing machine 50, and the sheet 51 can be replenished onto the mounting table 3 with the sheet supporting device 1 pulled out. After the sheet 51 is supplied to the stencil printing machine 50, the sheet supporting apparatus 1 can be returned to the stencil printing machine 50 as it is.

Further, above the sheet supply side of the mounting table 3 of the sheet supporting apparatus 1, when the mounting table 3 rises, the uppermost sheet of the sheets 51 deposited on the mounting table 3 comes into contact with the uppermost position. Discharge roller 51a for discharging the sheet
Is provided.

A registration roller pair 51b is provided downstream of the paper discharge roller 51a to adjust the discharge timing of the uppermost sheet of the sheet support device 1 discharged by the paper discharge roller 51a to the printing section 54. A guide path 51e for guiding the sheet to the printing unit 54 is provided downstream of the registration roller pair 51b.

Next, the operation of the sheet supporting apparatus 1 thus configured will be described. First, the case of replenishing the sheet 51 will be described with reference to FIG. At this time, the mounting table 3 is located at the sheet stacking state forming position A which is the lowest position, and the push-up member 2d is in a state of protruding from the hole 3f of the mounting table 3.

In this state, the operator holds the sheet supporting device 1
Is pulled out of the stencil printing machine 50 and the sheet 51 is placed on the mounting table 3.
Replenish. At this time, since the push-up member 2d projects from the hole 3f, the lowermost sheet of the replenished sheet 51 is pressed and pushed up by the push-up member 2d,
By this action, the side opposite to the sheet supply side of the sheet deposit (hereinafter, the side opposite to the sheet supply side is simply referred to as a rear side).
Is formed upward (see FIG. 1).

With such a simple structure, a curve is formed in the sheet deposit. However, since the curve is not directed upward to the sheet supply side as in the prior art, the sheet is curved upward. Even if a large number of sheets 51 are accumulated, an effective curve is formed on the rear side of the entirety of the large number of sheets, and the sheet supply side edge (hereinafter, simply referred to as the sheet front end) of the sheet deposit is attached to the contact member 2e. The abutting ends are accurately positioned and aligned.

As the force for causing the curvature, the weight of the sheet deposit is used, and this force increases in proportion to the thickness of the sheet deposit. For this reason, even if the thickness of the sheet deposit is large, the curve is formed efficiently, and the leading end of the sheet is accurately positioned and aligned.

When the sheet supporting apparatus 1 on which the sheet 51 is formed is returned into the stencil printing machine 50, an external force such as vibration acts on the mounting table 3, but the sheet deposit is curved. Since the sheet leading end is in contact with the contact member 2e, the sheet deposit does not collapse, and the position of the leading end is reliably maintained.

When the sheet supporting device 1 is returned into the stencil printing machine 50, the above-mentioned driving means is driven to drive the pulleys 6a, 6a.
b rotates, and the ropes 4a to 4d are evenly wound. As a result, the mounting table 3 rises by a predetermined amount while maintaining the horizontal state. As the mounting table 3 rises, the curving on the rear side of the sheet deposit is gradually eliminated, and when the sheet deposit position B is reached, the driving of the driving means is stopped (see FIG. 4).

At this time, the contact of the push-up member 2d with the sheet at the lowermost position of the sheet deposit has been eliminated, and the rearward bending of the sheet deposit has been completely eliminated.

That is, in the state where the mounting table 3 is lifted by the action of the driving means also serving as the curving removing means and is located at the sheet holding position B, the curving is removed from the sheet accumulating material. It is made horizontal following the upper surface of the mounting table 3.

At this time, since the contact state of the leading end of the sheet with the contact member 2e is maintained, the sheet deposit is accurately and reliably aligned at the leading end of the sheet, and is kept horizontal without curling due to bending. Will be retained.

Further, as the mounting table 3 is raised by driving of the driving means, the curving of the sheet deposit is eliminated, and the pressing force by the push-up member 2d acting on the sheet without generating a force parallel to the sheet surface. Is reduced or eliminated, and the state is shifted to a state in which the sheet deposit is stably held without causing the sheet 51 to shift.

In the sheet holding state at the sheet holding position B, the sheet at the uppermost position of the sheet deposits is
For example, long-term holding in a horizontal state that is not yet in contact with 1a and does not have a habit due to such a curvature is enabled.

It is to be noted that the above-mentioned simple structure is used to form the stacked state of the sheet and to hold the sheet deposit, instead of the structure in which the entire sheet is biased and held by inclining the entire sheet. It has become so.

In such a state that the sheet deposit is held, in the printing stage, the above-described driving means is driven, and the mounting table 3 is raised while maintaining the horizontal state. The driving of the driving means is stopped (see FIG. 5).

In this state, the contact member 2e at the leading end of the sheet
Is maintained as it is, the sheet deposit is held in a horizontal state with the sheet leading edge being accurately and surely aligned, and the sheet at the uppermost position of the sheet deposit is given to the discharge roller 51a by a predetermined amount. It is in a state where it can be discharged at any time by contact with pressure.

As described above, the driving means for moving the sheet deposit until it reaches the position where the uppermost sheet is discharged is also used as the curving removing means, thereby simplifying the structure.

When the discharge roller 51a is driven in this state, the sheet 51 is in a horizontal state at the time of holding and discharging the above-mentioned sheet deposit.
Is discharged to the guide path 51e without deformation due to the curl due to bending.

When the sheet is discharged by the discharge roller 51a, the sheet deposit is not curved, and
The sheet 51 is discharged without requiring an extra force at the time of discharging the sheet and is well separated from other sheets.

Then, the above-mentioned driving means is driven in accordance with the number of sheets from which the sheet deposits are discharged, and
Gradually rises while maintaining a horizontal state,
The sheet at the uppermost position of the sheet stack is the discharge roller 51a.
At a predetermined pressure.

As described above, in the present embodiment, when the sheet 51 is supplied onto the mounting table 3 and the stacking state of the sheet 51 is formed, the push-up member 2d moves the sheet 51 to the rear side portion of the sheet stack. An upward curvature is provided by using the weight of the sheet pile instead of going upward in the sheet leading end side, and an effective curve can be formed in the sheet pile regardless of the number of sheets. The tip is abutted against the abutting member 2e to accurately position and align the tip, and even when external force such as vibration acts on the mounting table 3, the sheet tip is reliably positioned without collapsing the sheet deposit. It can be maintained. For this reason,
A good image can be formed on the sheet 51 without being affected by the number of sheets to be deposited.

Further, when holding the sheet deposit in which the sheet accumulation state is formed, the driving means is driven to move up the mounting table 3, whereby the curving is removed from the sheet deposit, and the leading end is accurate. It is possible to hold and discharge the sheet deposits that are securely aligned and deposited in a horizontal state, thereby preventing deformation of the discharged sheet 51 and eliminating unnecessary force during sheet discharge. It has become. Therefore, it is possible to more favorably form an image on the sheet 51 and prevent the sheet 51 from jamming, and it is possible to reduce the load.

In the present embodiment, the mounting table 3 is placed in the sheet stacking state forming position A and the sheet 51 is
The sheet 51 is replenished while the mounting table 3 is located at the sheet holding position B. When the replenishment is performed, the mounting table 3 is lowered to the sheet accumulation state forming position A, and Similarly to the above, the sheet stacking state may be formed, and then the sheet may be raised to the sheet holding position B.

As described above, even when the mounting table 3 is lowered to form a curve by the push-up member 2d on the rear side of the sheet deposit, the force for causing the curve is the weight of the sheet deposit. Since there is no difference in the use of the curve, the curvature is formed efficiently as described above.

FIGS. 6 to 9 show, by experiments, a suitable arrangement position of the push-up member 2d of the sheet support device 1 with respect to various types of sheets. FIG. 6 shows the A3 size sheet placed vertically. FIG. 7 is an explanatory view showing a preferred arrangement position with respect to the A51 and 51, and FIG. 7 is an explanatory view showing a preferred arrangement position with respect to both the A3 and B4 size sheets 51 and 90 placed vertically, and FIG. Sheet 52
FIG. 9 is an explanatory diagram showing a preferred arrangement position for the sheet A, and FIG. 9 is an explanatory diagram showing a preferred arrangement position for both the A4 and B5 size sheets 52c and 91 placed horizontally.

The term “vertical placement” as used herein means that the short edge of the sheet is placed as the sheet supply side.
It means that the sheet longitudinal edge is placed as the sheet supply side.

As described above, since the sheet supporting device 1 employs the structure of the push-up member 2d that gives an upward curve, the various sheets 51, 52c, 9
The number of deposited 0,91 sheets is as large as 500 sheets. When a conventional sheet supporting apparatus is used, the number of stacked sheets is small, and at most about 250 sheets.

The position of the push-up member 2d is desirably within a range X1 to X4 surrounded by a two-dot chain line as shown in each figure.

Here, the push-up member 2d is set in the range X
Upstream side (left side in the figure) along the discharge direction with offset from 1 to X4
, The formation of the curve is insufficient, and if it is too close to the downstream side, the sheet rear end hangs down from the push-up member 2d, the pushing force in the discharge direction does not work sufficiently, and the sheet front end The contact member 2e does not sufficiently strike. Also, if the ranges X1 to X4 are shifted and shifted too much toward both side edges, it is not possible to sufficiently form a curve.

In particular, in FIG. 7, the cross-sectional shape of the push-up members 2d is 6.4 mm × 8 mm, the push-up height with respect to the sheet is about 8 mm, and the R shape is inclined at 30 °, and these push-up members 2d are three pairs. (6 pieces), both A3 and B4 size sheets 5 placed vertically
The desired arrangement position with respect to 1, 90 is specifically shown. If the push-up member 2d is disposed at such a position, both the A3 and B4 size sheets 5 placed vertically are arranged.
Also for the sheets 1 and 90, the rear portion of the sheet (the upstream portion in the conveyance direction) gradually rises, and both of the sheets 51 and 90 can be urged toward the downstream side.

As shown in ranges X1 to X4 in FIGS. 6 to 9, the push-up member 2d is provided closer to the rear end than an intermediate position between the front end and the rear end of the sheet.
Curves will be formed at positions corresponding to 1 to X4.

That is, since the curve is formed in an area less than half of the sheet area, the force required for bending is
The number of sheets is much smaller than when the entire sheet is curved. In addition, since the buckling deformation of the sheet deposit occurs only in the rear portion of the sheet deposit, the sheet deposit is more effectively curved even when the sheet deposit height is high due to a large number of sheets to be deposited. Are formed and positioning is performed.

FIG. 10 is a perspective view showing a sheet supporting apparatus 10 according to the second embodiment. The point that the sheet support device 10 of the second embodiment is different from the sheet support device 1 of the first embodiment is that the plurality of push-up members 2d are formed by connecting the plurality of push-up members 2d in the width direction. This is the point that the thrust-up member 2h is replaced.

Further, with this change, the plurality of holes 3f of the mounting table 3 are replaced with the elongated holes 3h which form a shape communicating with the holes 3f so that the push-up member 2h can protrude from the mounting table 3. I have.

Here, the sheet supporting device 1 of the first embodiment
In this case, the contact of the push-up member 2d with the sheet can be regarded as a discontinuous point. However, in the sheet supporting apparatus 10 of the second embodiment, the contact of the sheet with the push-up member 2h is a continuous point, that is, a line. In addition to the effect of the embodiment, the load on the sheet abutting on the push-up member 2h can be reduced, and the push-up member 2h
h can stabilize the pushing action.

FIG. 11 is a perspective view showing a sheet supporting device 20 according to the third embodiment, and FIG.
Is a front view showing the base 2j together with the rocking plate 3i.

The difference between the seat support device 20 of the third embodiment and the seat support device 1 of the first embodiment is that the base 2j
The structure is such that the push-up member 2i provided on the mounting table 3b gives a curvature to the rear portion of the sheet deposit via the swinging plate 3i provided on the mounting table 3m.

That is, a substantially T-shaped opening 3j is formed at the rear side of the mounting table 3m, and a swinging plate 3i slightly smaller than the opening 3j is inserted in the opening 3j. The sheet supply side portion of the rocking plate 3i is fixed to the mounting table 3m and is rotatably supported by the shaft 3k extending in the width direction, whereby the rear side portion of the rocking plate 3i is provided. However, it can swing vertically about the shaft 3k.

The push-up member 2i is provided below the rear side portion of the swing plate 3i, and the push-up member 2i is moved by the vertical movement of the mounting table 3m.
Acting on i, the swing plate 3i performs a predetermined swing described later.

The push-up member 2d and the swing plate 3
According to the sheet supporting apparatus 20 having the curve forming means constituted by i, when the mounting table 3m is positioned at the sheet accumulation state forming position A, as shown in FIG.
The rear side portion of the swing plate 3i abuts on i, and the swing plate 3i is inclined so that the rear side portion thereof is located upward, thereby forming an upward curve on the rear side portion of the sheet deposit. You. At this time, the contact of the swing plate 3i with the sheet is a surface. Then, by the action of the curving, the sheet tip of the sheet deposit is brought into contact with the contact member 2e, and the tip is accurately positioned and aligned.

When the stacking state of the sheets is thus formed, the mounting table 3m is raised by a predetermined amount. This mounting table 3
As the m increases, the swinging plate 3i rotates downward about the shaft 3k as a fulcrum while the rear portion contacts the push-up member 2i, thereby gradually bending the rear portion of the sheet deposit. Going to be resolved.

When the mounting table 3m reaches the sheet holding position B as shown in FIG. 14, the rocking plate 3i is brought into a horizontal state with its rear side portion abutting on the push-up member 2i. Thereby, the curvature of the rear side of the sheet deposit is completely eliminated, and the sheet deposit is held in a horizontal state.

At this time, the rear side portion of the swing plate 3i comes into contact with a stopper pin 3p protruding from the mounting table 3m.
The mounting table 3m to position the mounting table 3m at the sheet discharge position C
When the swinging plate 3i is further raised, the swinging plate 3i does not rotate further downward while maintaining the horizontal state, and the rear side portion of the sheet deposit hangs downward due to the further rising, and the positional deviation of the sheet front end is reduced. Is prevented from occurring.

As described above, in the third embodiment, the contact of the rocking plate 3i with the sheet is a surface, and therefore, compared with the discontinuous point in the first embodiment and the line in the second embodiment. The load on the sheet abutting on the swing plate 3i can be further reduced, and the push-up action can be further stabilized.

The number of the push-up members 2i may be one or more. In the case of one push-up member 2i, the push-up member 2i is preferably located substantially at the center in the width direction of the base 2j. Are preferably arranged symmetrically with respect to the center.

In the second and third embodiments, the size of the sheet and the setting direction (vertical or horizontal) are not particularly described. However, as described in the first embodiment, various sizes are set. It is needless to say that the present invention can be applied to any setting direction of the sheet, the vertical setting, and the horizontal setting.

FIG. 15 is a perspective view showing a sheet deposit curved by the sheet supporting apparatus according to the fourth embodiment. In the fourth embodiment, for example, an A3-size sheet 51 is used.

In the sheet supporting apparatus shown in FIG. 15A, a push-up member 2d (not shown) similar to that described above is provided opposite to one side 51r of the rear end of the sheet pile on which the sheet 51 is piled. The sheet deposit is pushed up by the push-up member 2d to form a curve shown by a solid line in the figure, and both end face positions (upper right, right The stopper members 41 and 42 are provided at the (lower position), and the positioning is performed by bringing the end surfaces into contact with the stopper members 41 and 42, respectively.

Further, in the sheet supporting apparatus shown in FIG.
Opposite members 1r and 51s are provided with push-up members 2d (not shown), respectively. The push-up member 2d pushes up the sheet deposit to form a curve shown by a solid line in FIG. A stopper member 42 is provided at the distal end position, and positioning is performed when the distal end contacts the stopper member 42.

In FIGS. 15 (a) and 15 (b), even if an external force acts in both the vertical and horizontal directions of the sheet deposit, the pushing-up member and the stopper member change the deposited state of the formed sheet. Therefore, almost the same effects as in the first embodiment can be obtained.

In the fourth embodiment, an example of application to a vertically placed A3 size sheet 51 is described. However, as described in the first embodiment, a sheet of another size or a horizontally placed sheet is used. Can be similarly applied.

In FIG. 15 (b), the push-up member 2 is opposed to both sides 51r and 51s of the rear end of the sheet deposit in order to form a more favorable curve in the sheet deposit.
d, and both sides 51 at the rear end of the sheet deposit.
r, 51s, the push-up member 2
A push-up member having a height lower than d may be provided.

The invention made by the inventor has been specifically described based on the embodiment. However, the invention is not limited to the above embodiment, and can be variously modified without departing from the gist of the invention. Needless to say,
For example, in the above embodiment, the sheet holding position B and the sheet discharging position C are separated, but the sheet may be held at the sheet discharging position C.

In the above embodiment, the sheet supporting devices 1, 10, and 20 are applied to the stencil printing machine 50. However, the present invention can be similarly applied to other printing machines and copiers.
The present invention is applicable to all image forming apparatuses.

[0101]

In the sheet supporting apparatus according to the present invention, when a sheet is supplied on the supporting member to form a stacked state of the sheet, the sheet forming side of the sheet is opposite to the sheet supply side of the sheet deposit by the curved forming means. The portion is given an upward curvature, not upward, by using the weight of the sheet deposit on the sheet supply side, so that an effective curve can be formed on the sheet deposit regardless of the number of sheets, and sheet feeding of the sheet deposit is performed. The side edge is brought into contact with the contact member to accurately position and align the edge, and even when an external force such as vibration acts on the support member, the sheet edge is securely positioned without collapsing the sheet deposit. Since the configuration is such that it can be maintained, it is possible to form a good image on the sheet regardless of the number of sheets to be deposited.

Further, when holding the sheet deposit in which the sheet deposit state is formed, the curl is removed from the sheet deposit by the curl removing means, and the sheet supply side edges are accurately and surely aligned to accumulate the sheet deposit. It is possible to hold and discharge the deposited sheet deposit in a horizontal state to prevent deformation of the discharged sheet (to prevent the sheet from curling due to bending), and
Since the configuration is such that no extra force is required at the time of discharging the sheet, better image formation on the sheet and prevention of jamming of the sheet can be achieved, and the load can be reduced.

Further, since the configuration is not such that the entire sheet is biased and held by being inclined, a complicated design can be eliminated and the design cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating a stencil printing machine to which a sheet supporting device according to a first embodiment is applied.

FIG. 2 is a perspective view of the sheet support device shown in FIG.

FIG. 3 is a front view of a base of the sheet support device shown in FIG. 2;

FIG. 4 is an operation explanatory view of the sheet supporting apparatus according to the first embodiment, and is an operation explanatory view showing a state where the mounting table is located at a sheet holding position.

FIG. 5 is an operation explanatory view of the sheet support device according to the first embodiment, and is an operation explanatory view showing a state where the mounting table is located at a sheet discharge position.

FIG. 6 is an explanatory diagram showing an arrangement position of a push-up member of the sheet support device according to the first embodiment, and shows a vertically placed A3.
FIG. 4 is an explanatory diagram showing a suitable arrangement position for a sheet of a size.

FIG. 7 is an explanatory diagram showing an arrangement position of a push-up member of the sheet support device according to the first embodiment, and illustrates a vertically placed A3.
FIG. 7 is an explanatory diagram showing a suitable arrangement position for both the B4 size sheet and the B4 size sheet.

FIG. 8 is an explanatory view showing an arrangement position of a push-up member of the sheet support device according to the first embodiment, and illustrates a state where A4 is placed horizontally.
FIG. 4 is an explanatory diagram showing a suitable arrangement position for a sheet of a size.

FIG. 9 is an explanatory diagram showing an arrangement position of a push-up member of the sheet support device according to the first embodiment, and shows A4 placed horizontally.
FIG. 9 is an explanatory diagram showing a preferred arrangement position for both the B5 and B5 size sheets.

FIG. 10 is a perspective view showing a sheet support device according to a second embodiment.

FIG. 11 is a perspective view showing a sheet support device according to a third embodiment.

FIG. 12 is a front view showing a base of a seat supporting device according to a third embodiment together with a swing plate.

FIG. 13 is an operation explanatory view of a main part of the sheet supporting apparatus according to the third embodiment, and is an operation explanatory view showing a state where the mounting table is located at a sheet stacking state forming position.

FIG. 14 is an operation explanatory view of a main part of the sheet supporting apparatus according to the third embodiment, and is an operation explanatory view showing a state where the mounting table is located at a sheet holding position.

FIG. 15 is a perspective view showing a sheet deposit curved by the sheet supporting apparatus according to the fourth embodiment, wherein (a) is a perspective view showing a state where one side of a rear end of the sheet deposit is pushed up, () Is a perspective view showing a state in which both rear ends of the sheet deposit are pushed up.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Seat support device, 2, 2j ... Base, 2d, 2h, 2
i: push-up member (curve forming means), 2e, 42: contact member (stopper member), 3, 3m: mounting table (support member), 3i: rocking plate (curve forming means), 50: stencil printing machine; 51, 52c, 90, 91: sheet, A: sheet accumulation state forming position, B: sheet holding position, C: sheet discharging position, X1 to X4: suitable arrangement range of the push-up member.

Claims (7)

[Claims] 1. A supporting member for supporting a lower surface of a sheet deposit formed by depositing a recording sheet, and a sheet supply side edge of the sheet deposit deposited on the supporting member is brought into contact with the supporting member. An abutting member for determining a position of an edge, and a position where the sheet is replenished on the support member to form a stacking state of the sheet and a sheet deposit in which the sheet stacking state is formed; A sheet support device in which at least the support member is movable between a position where the sheet is placed and a portion opposite to the sheet supply side of the sheet deposit deposited on the support member. And a curving unit that removes the curving of the sheet deposit provided by the curving unit. The curving unit further includes a curving unit that removes the curving of the sheet deposit provided by the curving unit. When the sheet is replenished to form the stacking state of the sheet, the curve forming means acts to impart the curve to the sheet stack, and at least the sheet stack in which the sheet stacking state is formed The sheet support device is characterized in that when the sheet is held, the curve removing means acts to remove the curve from the sheet deposit. 2. The curve of the sheet deposit provided by the curve forming means is closer to the opposite edge than from an intermediate position between the edge on the sheet supply side and the edge on the opposite side. The sheet support device according to claim 1, wherein the sheet support device is formed. 3. The sheet at the uppermost position of the sheet deposit is a sheet discharged for recording from the supply side edge in a state where the curving is removed by the curving removing means. The sheet supporting device according to claim 1. 4. The bend forming means comprises a plurality of push-up members for forming the bend by pressing a sheet at a lowermost position of the sheet deposit and pushing up the sheet at the lowermost position. The sheet support device according to claim 1. 5. The push-up member is fixed to a base located below the support member, and the support member supporting the sheet deposit moves downward to press the sheet at the lowest position. 5. The method according to claim 4, wherein
The sheet support device as described in the above. 6. The driving device for moving the supporting member in a direction perpendicular to the sheet surface after the bending is removed so as to eliminate the pressing of the lowermost sheet by the pushing-up member. The sheet support device according to claim 4, wherein the sheet support device is formed. 7. The driving means according to claim 1, wherein
7. The sheet supporting device according to claim 6, wherein the sheet supporting device also serves as a driving unit for moving the uppermost sheet until it reaches a position where the sheet is discharged for recording.