JPH05330669A - Sheet stacking device - Google Patents

Abstract

PURPOSE:To arrange the width direction end parts of sheets in the case of placing layered sheets on a sheet stacking device. CONSTITUTION:A crossed helical gear 11 fitted to the motor shaft of a motor 3 fitted to a cassette case 20 is meshed with a helical gear 9, and the helical gear 9 is meshed with a rack 13. The rack 13 is fixed to a movable sheet regulating plate 4, and the movable sheet regulating plate 4 is provided with a pressure detecting means 5. When sheets are placed on a sheet stacker plate 1 and the motor 3 is rotated, the rack 13 moves to the right, the movable sheet regulating plate 4 advances toward a fixed sheet regulating plate 7, and pressure is applied to the sheet end face by the pressure detecting means 5 and fixed sheet regulating plate 7 so as to arrange the paper face in the width direction of the sheets. The applied pressure is determined by controlling the motor 3 by a control device on the basis of a pressure signal detected by the pressure detecting means 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a width adjustment for aligning widthwise ends of a large number of sheets in an image forming apparatus such as a copying machine.

[0002]

2. Description of the Related Art Conventionally, in a sheet stacking apparatus for stacking sheets such as transfer sheets, in the case of one side reference in which the widthwise ends of the sheets are fixed positions, the sheet regulating plate on one side is used. It was loaded by hitting against. With the center of the width direction of the sheet as a fixed position through either size of the sheet, the center reference field is either
It was loaded against the sheet regulation plate. However, if the space between the two sheet regulation plates is larger than the sheet width in the sheet regulation plate at the other end where the sheets were not abutted, the sheets do not collide, or both sheet regulation plates are urged by the elastic member in the contracting direction. He was receiving a certain amount of pressure regardless of the amount of seats.

[0003]

In the prior art, the sheet position is not fixed if the distance between both sheet regulating plates is larger than the sheet width. Further, when the elastic member urges between the sheet regulating plates in the contracting direction, the pressure applied to one sheet changes depending on the amount of the sheet, so that the sheet cannot be regulated reliably. This has been a cause of impeding the improvement of the sheet feeding performance such as skewing, paper feeding failure, and catching on the nail in the case of a cassette with a nail.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide a sheet stacking apparatus capable of stacking sheets without complicated work and improving the sheet feeding performance.

[0005]

A first aspect of the present invention is a sheet stacking apparatus provided in a sheet feeding section of an image forming apparatus or the like, and is movable to regulate a width direction of a sheet placed on a sheet stacking plate. In the sheet stacking device including the sheet regulating member, a movable sheet regulating member is moved in the width direction of the sheet to press the end portion in the width direction of the sheet, and a pressure detecting unit that detects pressure applied to the sheet. And a control device for inputting a pressure signal detected by the pressure detection means and controlling the width-shifting device.

A second invention of the present invention is the first invention, characterized in that the width aligning device is provided with a control device for reducing the pressing force detected by the pressure detecting means to a predetermined pressure after the width aligning. It is the sheet stacking device described.

A third aspect of the present invention is a sheet stacking device provided in a sheet feeding portion of an image forming apparatus or the like, which includes a movable sheet regulating member for regulating the width direction of a sheet placed on a sheet placing plate. In the sheet stacking apparatus provided with the sheet regulating member, the sheet regulating member is a member that swings in the forward and reverse directions, and has a plurality of pressurizing portions that are in contact with the sheet end portion, and at least one of the pressurizing portions has a pressure detecting means. It is a characteristic sheet stacking device.

A fourth aspect of the present invention is the sheet stacking device according to any one of the first to third aspects of the invention, which operates the width-shifting device before the sheet feeding device operates.

A fifth invention of the present invention is the sheet stacking apparatus according to the fourth invention, wherein a machine to which the sheet stacking apparatus is attached drives the width-shifting device during the preparatory operation.

A sixth invention of the present invention is the sheet stacking apparatus according to the fourth invention, characterized in that when the sheet stacking apparatus is mounted on a machine to which the sheet stacking apparatus is mounted, the width aligning device is driven.

A seventh aspect of the present invention is the sheet stacking apparatus according to the fourth aspect of the invention, which drives the width-shifting device when the power of a machine equipped with the sheet stacking apparatus is turned on.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment] FIGS. 1 and 2 show a sheet stacking apparatus according to an embodiment of the present invention.

A flat sheet stacking plate 1 is supported by a plurality of coil springs 21 on the bottom of a cassette case 20 having a housing. The sheet stacking plate 1 is vertically movably positioned on a supporting member 14 provided upright on the cassette case 20. A screw gear 11 meshing with the helical gear 9 is fixed to the motor shaft of the motor 3 fixed to the cassette case 20. The helical gear 9 is rotatably supported by the cassette case 20 and meshes with a rack 13 fixed to a movable sheet regulating plate 4 provided as a movable sheet regulating member. In the above, the motor 3, the screw gear 11, the helical gear 9, and the rack 13 constitute a width-shifting device.

The movable sheet regulating plate 4 is a cassette case 20.
It is movable by engaging with a guide (not shown) in the left-right direction.
A fixed sheet regulation plate 7 is fixed to the cassette case 20 so as to face the movable sheet regulation plate 4. In the moving range of the movable sheet regulating plate 4, the sheet stacking plate 1 is notched and has a notch concave portion 1c. The movable sheet regulating plate 4 is provided with a pressure detecting means 5 having a piezoelectric element, for example, at a position in contact with the end of the sheet 2 placed on the sheet stacking plate 1. It can be considered that the pressure detecting means 5 does not displace even when a pressure is applied, and serves as a sheet regulating member that regulates the sheet end portion. The motor 3 and the pressure detection means 5 are wired to the control device 10. The control device 10 receives the signal from the pressure detection means 5 and drives the motor 3 so that the pressure detection means 5 controls the pressure applied to the end portion of the sheet 2 to a predetermined pressure, which will be described later. Controls the action of. The control device 10 is provided on a machine equipped with the sheet stacking device, and includes a motor 3, a pressure detection unit 5, and a control device 1.
The wiring between 0 is made long so that the sheet stacking device can be pulled out from the machine, or is provided between the cassette case 20 and the machine, and is connected via a connector which attaches and detaches the cassette case 20 to and from the machine. Arrange.

When the sheet stacking apparatus having such a structure is mounted on the sheet feeding section of the image forming apparatus, a sheet feeding roller such as a half-moon roller 6 can act on the sheet 2 (FIG. 3).

The operation of the above configuration will be described. Figure 1,
When the second sheet 2 is not placed, the movable sheet regulation plate 4
The distance between the pressure detecting means 5 and the fixed sheet regulating plate 7 provided in the sheet is slightly wider than the width of the sheet 2 as shown in FIG.
Therefore, there is a gap between the sheet 2, the pressure detecting means 5, and the fixed sheet regulating plate 7.

When the sheet 2 is placed on the sheet writing plate 1 as shown in FIG. 3, the sheet stacking plate 1 compresses the coil spring 21 and descends.

When the sheet 2 is placed on the sheet stacking plate 1, there is a gap between the sheet 2 and the fixed sheet regulating plate 7 and the pressure detecting means 5 as shown in FIG. When the motor 3 is energized, the screw gear 11 rotates and the helical gear 9 rotates. The helical gear 9 feeds the rack 13 to the right, the movable sheet regulating plate 4 and the pressure detecting means 5 move forward to the right, and the pressure detecting means 5 contacts the sheet 2 and displaces the sheet 2 to the right and fixes it. The sheet 2 is sandwiched between the sheet regulation plate 7 and the pressure detection means 5, and the sheet 2 is pressed and aligned so as to align the edges of the sheet and press the sheet 2 to such an extent that a loop 8 is formed (FIG. 4). Subsequently, the motor 3 rotates in the reverse direction, the movable sheet regulating plate 4 and the pressure detecting means 5 move backward,
The pressure detecting means 5 is separated from the sheet edge of the sheet 2 and the state shown in FIG. The first control method performed by the control device 10 is that the pressure at which the loop 8 of the seat 2 is generated by the pressure signal detected by the pressure detection means 5 is input to the storage device of the control device in advance, and the motor 3 becomes the pressure. Is reversely rotated and the motor 3 is rotated by a predetermined rotation angle (numerical control), or is rotated by a time limiter for a predetermined time (time control). The second control method is applicable when the size of the seat 2 is fixed, and the position of the pressure detecting means 5 shown in FIG. The motor 3 is numerically controlled so as to move the sheet regulation plate 4 forward. Also, when retreating, numerical control is performed from the position of FIG. 4 to the position of FIG. 5 (numerical control).

In the state shown in FIG. 5, the pressure applied to the sheet 2 is removed, and the edges of the sheet 2 are aligned. The motor 3 continues to rotate normally, the movable sheet regulating plate 4 and the pressure detecting means 5 move forward,
When the pressure detecting means 5 presses the sheet 2 to reach a predetermined pressure which is determined so that the sheet can be fed smoothly, the pressure signal is sent to the control device 10 to stop the motor 3 (FIG. 6).

Further, in this embodiment, the sheet stacking device is installed as a paper feed cassette in, for example, a copying machine. Since the sheet feeding roller of the copying machine is the half-moon roller 6 and the paper cassette is freely attachable / detachable, when the copy button is pressed, the control device 10 operates the width-shifting device before the half-moon roller 6 rotates. It has become. In the case of the present example, the final pressure detected by the pressure detection shown in FIG. 6 is such that the movable sheet regulating plate 4 is stopped when 20 g is detected by the A4 vertical size cassette of Japanese Industrial Standard Paper. Final pressure varies with sheet size. When the sheet feeding roller is a cylindrical roller, there are various means for feeding the sheet. For example, the cylindrical roller is usually in non-contact with the sheet 2, and there is a type in which the cylindrical roller goes down by a sheet feeding signal to feed the sheet. Also in this case, width adjustment may be performed before the rotation of the sheet feeding roller.
It is also possible to set the operation timing of the width-shifting device after feeding the set number of sheets and before discharging the sheets from the copying machine. Further, a method of providing a cassette detecting means and performing a width adjustment operation by a cassette insertion signal and a method of performing the width adjustment after the main body of the copying machine is turned on may be used. With this method, it is not necessary to perform width adjustment every time the copy button is pressed, and it is effective in terms of durability. Further, by providing a sheet absence detecting means and providing a control device for returning the movable sheet regulating plate 4 and the pressure detecting means 5 to a predetermined position (FIG. 3) where it is easy to stack the sheet when the sheet absence is detected, it is easy to stack the sheets. become. In this case, the sheet stacking device cannot be removed from the copying machine until it returns to the predetermined position. Alternatively, the electric wiring may be made flexible so that the electric system is always connected even when the sheet stacking device is pulled out. This is easily possible with known techniques.

[Second Embodiment] FIGS. 7 and 8 show an example in which movable sheet regulating plates are provided on both sides.

A pinion 22 is fixed to the motor shaft of the motor 3 fixed to the bottom of the cassette case 20, and racks 23a and 23b that move in the left-right direction are meshed on both sides across the diameter of the pinion 22. Racks 23a, 2
3b is integrally or integrally fixed to the movable sheet regulating plates 4a and 4b. The movable sheet regulating plates 4a and 4b are movably fitted to unillustrated left and right guides provided in the cassette case 20, respectively. Movable sheet regulating plates 4a and 4b are provided on the left and right protruding guide portions 1a and 1b of the sheet stacking plate 1.
The slide portions 24a and 24b installed upright are movably fitted. The power transmission device from the motor 3 to the racks 23a and 23b constitutes a sheet width-shifting device, and the movable sheet restricting plates 4a and 4b are output parts of the width-shifting device. A pressure detecting means 5 is provided on the movable sheet regulating plate 4a on one side so as to face the movable sheet regulating plate 4b on the other side. Sheet introducing portions 26a and 26b are provided above the movable sheet regulating plate 4b and the opposing surface of the pressure detecting means. The sheet stacking plate 1 has cutout recesses 1c and 1d at portions that interfere with the movable sheet regulating plates 4a and 4b and the members that move together with the movable sheet regulating plates 4a and 4b.

As shown in FIG. 9, when the sheets 2 are stacked on the sheet stacking plate 1 and the motor 3 is rotated, the pinion 22 is rotated, so that the racks 23a and 23b move the movable sheet regulating plates 4a and 4b by the same amount. Exercise in the direction you want it to.
The movable sheet regulating plates 4a and 4b and the pressure detecting means 5 advance,
The movable sheet regulation plate 4b and the pressure detection means 5 contact the end portion of the sheet 2 in the width direction. Further, the movable sheet regulating plates 4a, 4
b until the pressure reaches the first set pressure set by the control device 10 that controls the width-shifting device in accordance with the pressure detection of the pressure detection means 5, that is, until the loop 8 of the sheet occurs as shown in FIG. And then rotate the motor 3 in the reverse direction,
Movable sheet regulation plate 4 until the set second set pressure is reached
a, 4b are moved, and the width-shifting device is stopped there,
The position of the sheet 2 is regulated when the sheet 2 is flat as shown in FIG. For example, in A4 vertical standard size,
The first set pressure in the state shown in Fig. 11 is 300 g, and the second set pressure in the state shown in Fig. 11 is 20 g. Also, the sheet size is A
If it is larger than 4 vertical size, both the first and second set pressures are made higher, and if it is smaller than A4 vertical size, both the first and second set pressure are made lower. It is better to change the set pressure according to the maximum number of sheets loaded.

[Third Embodiment] FIGS. 12 to 17 show a third embodiment. As shown in FIG. 12, the rotating sheet regulating plate 12 is rotatably attached to a shaft 15 provided upright on the cassette case 20. As in the first embodiment, the motor 3, the screw gear 11,
A helical gear 9 is provided. The helical gear 9 is a gear 16 rotatably supported by a shaft provided upright on the cassette case 20.
The gear 16 meshes with the gear 17 fixed to the rotating sheet regulating plate 12. At both ends of the rotating sheet regulating plate, a pad 12a that comes into contact with the sheet 2 and a pressure detecting means 5 are provided so as to face the fixed sheet regulating plate 7, respectively. The pressure detecting means 5 is pivotally mounted so as to swing with respect to the rotating sheet regulating plate 12 and hit the end surface of the sheet 2 with the entire width.

Before stacking the sheets 2, the pad 12a facing the width of the stacked sheets 2 as shown in FIG.
And the fixed sheet regulating plate 7, and the rotating sheet regulating plate 12 so that the facing distance between the pressure detecting means 5 and the fixed sheet regulating plate 7 is large.
Is located. In FIG. 12, the sheets 2 are stacked and the motor 3 is urged to screw the gears 11, the helical gears 9, and the gears 1.
6, 17 and the rotation sheet restriction plate 12 is transmitted to the shaft 15
Is rotated clockwise around the center of the sheet to contact the pad 12a with the sheet edge of the sheet 2 and press the sheet 2 against the fixed sheet regulation plate 7 to align the edges of the sheet. This pressure is applied until the sheet loop 8 is formed as shown in FIG. The set value of the pressing force is controlled by the control device 10 that controls the motor 3,
Further, after the controller 10 pressurizes to a set value by numerical control or time-limiting means, the motor 3 is rotated in the reverse direction, and the rotating sheet regulating plate 12 is rotated about the shaft 15 counterclockwise. The pad 12a is separated from the sheet 2, and the pressure detecting means 5 at the end portion of the rotating sheet regulating plate 12 presses the sheet 2 to a predetermined pressure, and the control device 10 reversely rotates the sheet 2, The width aligning device is stopped and the sheet 2 is set (FIGS. 16 and 17). For example, in a standard size of A4 vertical size, a pressure of 20 g is applied to the sheet. If the sheet size is larger than the A4 vertical size, it is set to be higher than 20 g, and if the sheet size is small, it is set to be lower than 20 g. This method is particularly small (A5, B5, etc.)
Is effective for. Further, in the case of a cassette with a claw, the amount of the sheet hooked on the claws at both ends is uniform, which is particularly effective. In this case, needless to say, the moving amount of the movable sheet regulating plate must be set so that the claw cannot be disengaged from the sheet.

[Fourth Embodiment] FIGS. 18 and 19 show another embodiment. In this embodiment, a sheet regulating member provided on a moving sheet regulating plate or a fixed sheet regulating plate, that is, an abutting portion for contacting the sheet is provided at two places in the feeding direction of the sheet 2, and the sheet 2 is at two places in the feeding direction. The width is adjusted in. FIG. 18 shows an example of the central reference, and FIG. 19 shows an example of the one-sided reference.
In the case of the central reference, the pressure detecting means 5 is used as the sheet regulating member.
In addition to the hitting portion 4b-1 of the movable sheet restraining plate 4b facing the pressure detecting means 5, the hitting portions 4a-2 and 4b-2 face the respective sheet restraining plates 4a and 4b, and the width of the sheet 2 The width of the sheet 2 is regulated by applying the pressure detecting means 5 and the hitting portion 4a-2 to the paper end on one side in the direction and hitting the hitting portions 4b-1 and 4b-2 to the paper end on the other side. In the case of the one-sided reference shown in FIG. 19, the pressure detecting means 5 fixed to the movable sheet regulating plate 4 and the fixture portion 4-1 standing on the regulating plate 4 are opposed to the fixed sheet regulating plates 7a at two positions, respectively. 7b is provided. The width aligning device of these embodiments is the same as that of the first or second embodiment.

In these embodiments, the number of the pressure detecting means 5 is one, but the pressure detecting means 5 may be provided at a plurality of places so as to contact the sheet edge of the sheet of the member provided as the regulating member.

[0029]

According to the first aspect of the present invention, the width aligning device is provided with the pressure detecting means for detecting the pressing force at the time of the widthwise shifting of the sheet, and the pressure signal detected by the pressure detecting means is used through the control device. Since the advancing / retreating of the width adjusting device is controlled, it is possible to surely perform the width adjusting for aligning the ends in the width direction of the stacked sheets regardless of the size of the sheets.

In the second invention of the present invention, since the pressing force can be reduced after the width of the sheet is shifted in the first invention, the paper feeding operation can be made smooth.

According to a third aspect of the present invention, the sheet regulating member is a member that swings in the forward and reverse directions and is provided with a plurality of pressing portions that are in contact with the sheet member. The effect of providing the end is great, and the final pressurizing force is detected by the pressure detecting means and becomes a predetermined pressure, so that the sheet is smoothly supplied.

According to the fourth aspect of the present invention, since the width aligning device is operated before the sheet feeding device is operated, the sheet feeding is not performed while the sheets are not aligned.

According to a fifth aspect of the present invention, since the width-shifting device is driven during the preparatory operation of the machine to which the sheet stacking device is attached, for example, when a sheet feeding cassette (sheet stacking device) is attached to the image forming apparatus. In addition, even if the stacked sheets are misaligned, the sheets are aligned by the width adjustment because the width adjustment is performed during the pre-rotation of the photosensitive drum or the like in the preparatory operation for pressing the copy button to perform the first copy button. Therefore, paper feeding becomes smooth.

According to the sixth aspect of the present invention, since the width is adjusted when the sheet stacking device is mounted on the machine, the sheet width direction ends are not aligned in the sheet stacking device because they are removed from the machine. However, even if the sheet stacking apparatus functions, the widthwise ends of the sheets are aligned before the sheet stacking device functions, so that the sheets are fed smoothly.

According to the seventh aspect of the present invention, when the power of the machine to which the sheet stacking apparatus is mounted is turned on, the width of the machine is adjusted. Therefore, when the power of the machine is turned off and the sheet stacking apparatus is replaced. Even if the widthwise edges of the sheet are not aligned, the machine can be used without considering whether or not the width aligning device has operated.

[Brief description of drawings]

FIG. 1 is a plan view of an embodiment of a sheet stacking device of the present invention.

FIG. 2 is a front sectional view of FIG.

FIG. 3 is a front sectional view showing the operation of FIGS.

FIG. 4 is a front sectional view showing the operation of FIGS.

FIG. 5 is a front sectional view showing the operation of FIGS.

FIG. 6 is a front sectional view showing the operation of FIGS.

FIG. 7 is a plan view of another embodiment of the sheet stacking device of the present invention.

8 is a front sectional view of FIG. 7.

FIG. 9 is a front sectional view showing the operation of FIGS.

FIG. 10 is a front sectional view showing the operation of FIGS.

FIG. 11 is a front sectional view showing the operation of FIGS.

FIG. 12 is a plan view of still another embodiment.

13 is a front sectional view of FIG.

FIG. 14 is a plan view showing the operation of FIGS.

15 is a front sectional view of FIG.

FIG. 16 is a plan view showing the operation of FIGS.

17 is a front sectional view of FIG.

FIG. 18 is a plan view of an example in which a sheet regulating member is provided at the front and rear.

FIG. 19 is a plan view of an example in which a sheet regulating member is provided at the front and rear.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 sheet stacking plate 2 sheet 4 movable sheet regulating plate 5 pressure detecting means 7 fixed sheet regulating plate 12 rotating sheet regulating plate

Claims (7)

[Claims] 1. A sheet stacking apparatus provided in a sheet feeding unit of an image forming apparatus or the like, the sheet stacking apparatus including a movable sheet regulating member that regulates a width direction of a sheet placed on a sheet stacking plate. A moving device for moving the movable sheet regulating member in the width direction of the sheet to press the end portion in the width direction of the sheet, a pressure detecting unit for detecting the pressure applied to the sheet, and a pressure signal detected by the pressure detecting unit are input. A sheet stacking device having a control device for controlling the width adjusting device. 2. The sheet stacking apparatus according to claim 1, further comprising a control device that reduces the pressing force detected by the pressure detecting means to a predetermined pressure after the width-shifting device shifts the width. 3. A sheet stacking apparatus provided in a sheet feeding unit of an image forming apparatus or the like, the sheet stacking apparatus including a movable sheet regulating member that regulates a width direction of a sheet placed on a sheet placing plate. The sheet stacking device is a member that swings in the forward and reverse directions, has a plurality of pressurizing portions that are in contact with the sheet end portion, and has a pressure detecting means in at least one pressurizing portion. .. 4. The sheet stacking device according to claim 1, wherein the width aligning device is operated before the sheet feeding device operates. 5. The sheet stacking device according to claim 4, wherein the machine to which the sheet stacking device is attached drives the width-shifting device during the preparatory operation. 6. The sheet stacking device according to claim 4, wherein the width aligning device is driven when the sheet stacking device is mounted on a machine to which the sheet stacking device is mounted. 7. The sheet stacking device according to claim 4, wherein the width adjusting device is driven when the power of a machine equipped with the sheet stacking device is turned on.