JPH04235832A - Sheet material carrying device - Google Patents

Abstract

PURPOSE:To send out the last sheet without breaking it in a carrying device by energizing the loaded sheet material against the carrying reference plane to carry it in an adequate position. CONSTITUTION:A pushing member 31, which functions to push a loaded sheet material P against a carrying reference plane 1a, is equipped with a pressing portion 31b, which presses the fixed number of sheets counted from the top of the sheet material P and, by setting the pressing force so as to prevent the last sheet from buckling, the sheet material can be sent out from an adequate position to the last.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet material stacking device used in an image forming apparatus such as a copying machine.

0002

[Prior Art] When automatically feeding sheet materials, a cassette loaded and stored with sheet materials of a predetermined size is installed in a copying machine, and the sheets are fed one by one using a feeding means such as a feeding roller in the copying machine. There is something to do. In the paper feed cassette used for this product, the internal dimensions in the width direction of the sheet stacking section that stores the sheet materials are determined by taking into account variations in dimensions when cutting the sheet materials, expansion when absorbing moisture, etc. A margin of about 1 to 2 mm is provided for each size.

[0003] In this case, it is conceivable that due to improper setting during stacking, the side edges of the sheet materials may be fed without reliably hitting the conveyance reference surface of the paper feed cassette. As shown in 8, a side pressing member 3 having a spring property is attached to the non-reference side to keep the side end Pa of the stacked sheet materials P pressed against the conveyance reference surface 1a at all times. By means of the side pressing member 3, the sheet material P loaded on the cassette middle plate 4 of the cassette 1 is always fed in an appropriate state with the registration in the width direction.

0004

[Problems to be Solved by the Invention] However, in the conventional example described above, in order to always abut the sheet materials P loaded in the paper feed cassette 1 against the conveyance reference surface 1a regardless of the amount of the sheet materials loaded, it is necessary to use the side pressing member. The spring force in Step 3 requires a minimum force sufficient to pull together the fully loaded sheet materials, but with this spring force setting, the loaded sheet materials P are sequentially fed from the top and approach the last sheet. When this happens, the sheet material P with a small loading amount is subjected to more spring pressure than necessary, and the sheet material P may buckle and become creased.

On the other hand, if the spring force of the size pressing member 3 is set so as not to buckle the last paper, the spring force will not be sufficient when fully loaded, and the sheet material P will remain deviated in widthwise registration. In some cases, the item was sent away.

The present invention has been made in view of the above problems, and its object is to provide a sheet material loading device that can supply sheet materials at appropriate positions regardless of the amount of sheet materials loaded. Our goal is to provide the following.

[0007]

[Means for Solving the Problems] A first aspect of the present invention is to provide a presser member for pressing the side edges of stacked sheet materials to urge them against a conveyance reference surface, and a fixed number of sheets from the top of the sheet materials to be pressed. It is configured so that it can be pressed.

[0008] The second invention includes a presser member for pressing the side edges of the stacked sheet materials and urging them against the conveyance reference surface.
The holding member is movable in the stacking direction of the sheet materials, and is provided with a pressing portion that presses a fixed number of sheets, and an abutment member that abuts the uppermost surface of the stacked sheet materials.

[0009]

[Operation] According to the first invention, the side of the uppermost sheet material that is fed by pressing only a certain amount of the sheet material from the uppermost portion of the stacked sheet materials against the conveyance reference surface. It is possible to abut the end portion against the conveyance reference surface, and also to properly abut the last paper against the conveyance reference surface without buckling the sheet material.

According to the second invention, by bringing the contact member into contact with the top of the stacked sheet materials, even if the position of the top of the sheet materials changes, the presser can follow the change. Since the member moves, the pressing member can always press a fixed number of sheet materials.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1 to 3 show a first embodiment of the present invention. It should be noted that the same members as in the prior art will be described with the same reference numerals.

In the paper feed cassette 1, a side presser member 31 having spring properties is attached to the non-reference side of the sheet stacking section which has a larger margin in the width direction than the sheet material P to be used.

The side pressing member 31 includes a plate-shaped portion 31a having elasticity to generate a biasing force, and a contact portion provided at an end of the plate-shaped portion 31a and abutting against a side edge of the sheet material P. 31b, and a relief portion 31c that does not come into contact with the sheet material P,
Tapered portion 31d connecting contact portion 31b and relief portion 31c
This side pressing member 31 is biased in the direction a in FIGS. 1 and 2. If the sheet material P is improperly set and the side end Pa of the sheet material P is set away from the conveyance reference surface 1a, a force is exerted by the side presser member 31 to push it back toward the conveyance reference surface 1a.

By the way, the side pressing member 31 at this time
As shown in FIG. 4, the spring force must be set to a force f1 or less that does not buckle the paper even when pushing the last sheet of paper.

[0015] Accordingly, the amount of loaded sheet materials P that can be reliably pressed is limited to n1 sheets or less, as seen from FIG.

However, on the other hand, the uppermost surface of the sheet material P loaded in the paper feed cassette 1 is exposed to a push-up spring 5 provided between the cassette middle plate 4 and the paper feed cassette, and a separation claw 6 that regulates the push-up force. Due to both of these factors, the height is maintained at a nearly constant level regardless of the load capacity. Therefore, the contact portion 3 of the side presser member 31 is adjusted so that the pressing force f1 is applied within the range of paper thickness b from the top surface of the stacked sheet materials P to the n1th sheet.
By setting the dimensions of 1b, it is possible to feed the sheet material P in a state where it is always properly abutted against the conveyance reference surface 1a, regardless of the loading amount, even if there are variations in the size of the sheet material P or poor setting. Become.

Note that each time the uppermost sheet material is fed, the sheet materials from the n1th sheet to the bottom sheet are successively pushed up by the push-up spring 5 through the cassette middle plate 4 and abut against the side presser member 31. However, the sheet material P is smoothly pushed up along the tapered surface 31d of the side presser member 31 without getting caught on the way.

(Other embodiments) A second embodiment is shown in FIGS. 5 and 6.

As mentioned above, by applying pressure to as few sheet materials P as possible close to the top of the stacked sheet materials P with the side presser, even when only the last sheet of the stacked sheets is left, it is buckled with a small pressure. The sheet material P can be reliably brought to the conveyance reference surface 1a side without any problems. Therefore, the second embodiment is designed to ensure that only a small number of sheets can be pressed from the topmost sheet, and the sheet material P
It has a side presser member 32 that comes into contact with the upper surface of the uppermost sheet and serves as a reference in the height direction when the sheets are stacked.

[0020] The side pressing member 32 includes an abutting portion 32a,
Relief portion 32b, tapered portion 32c, and upper reference portion 32d
It has a degree of freedom in the X direction and the Y direction with the support shaft 7 as the center. It is biased by a spring 8 provided on the cassette body 1.

According to this configuration, after loading the sheet materials, the upper reference portion 32b of the side presser member 32 is moved to the uppermost sheet Pc.
Put it on top. The side pressing member 32 has a back surface 32b urged by the spring 8 to press the sheet against the reference surface side 1a. The height at which the sheet material P is pressed is determined by the upper reference portion 32.
The height I of the pressing surface can be determined from a to one part, and a certain number of sheet materials P can be pressed accurately.

Furthermore, in the side presser member 32 having this configuration, even if the position of the top of the sheet material P is not maintained constant, it moves according to the top position and always maintains the I dimension from the top of the sheet material. can be pressed. Therefore, in addition to separation claw type cassettes, the present invention can also be applied to cassettes in which the top position of the sheet material changes depending on the paper feeding.

In the above embodiments, the urging means is shown as a plate spring, but the urging means is not limited to this, and it goes without saying that various pressing means such as a coil spring can be applied.

Furthermore, the structure of the side pressing members 31 and 32 is not limited to the above embodiment, and the sheet material P is held on the reference surface 1.
Various forms can be applied as long as the structure can be pressed toward the a side.

Furthermore, it goes without saying that the present invention is also applicable to a so-called universal cassette, which can handle sheet materials P of various sizes in one paper feed cassette by changing the position of the side guide. do not have.

By the way, the paper feed cassette may be provided with a member that comes into contact with the side surface of the stacked sheets and assists in separating the sheets. For example, by applying something like Velcro tape or Velcro tape (both are trade names) to the sides of the stacked sheets, an effect is created to separate the sheets, but in the present invention, these auxiliary members are Sheet contact portions 31b, 32a of presser members 31, 32 and tapered surfaces 31d, 32 that continuously connect downward from the contact surfaces
It can be pasted on c.

In the above embodiment, the present invention is applied to the paper feed cassette, but in addition to the paper feed cassette, the sheet materials stacked on the tray are moved up and down by other devices, such as driving means such as a motor. It can be applied to a so-called deck type sheet material loading device that moves.

[0028]

[Effects of the Invention] As explained above, according to the present invention, regardless of the amount of sheet material loaded, it is possible to always make the side surface of the topmost sheet material abut against the transport reference surface of the cassette in an appropriate state. Therefore, the fed sheet material can be conveyed while minimizing registration deviation in the side direction, and has the effect that appropriate image quality can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a first embodiment of the present invention;

FIG. 2 is an enlarged perspective view of the main parts of the first embodiment of the present invention;

FIG. 3 is a perspective view of the first embodiment of the present invention;

[Fig. 4] A diagram showing the relationship between the loading amount of sheet material and the contact force of sheet material,

FIG. 5 is a plan view of main parts of a second embodiment of the present invention;

[Figure 6]
An enlarged perspective view of main parts of a second embodiment of the present invention,

FIG. 7 is a plan view of a paper feed cassette showing an example of a conventional sheet material loading device;

8 is a sectional view taken along line AA in FIG. 7. FIG.

[Explanation of symbols]

1 Paper feed cassette (sheet material stacking device) 1a Conveyance reference planes 31, 32 Side press members (press members) 31b, 3
2a Pressing parts 31d, 32c Taper part 32d Upper reference part (abutting member)

Claims (4)

[Claims] Claim 1: A sheet material loading device comprising a presser member that presses side edges of stacked sheet materials to urge them toward a conveyance reference surface, wherein the presser member is moved from the top of the stacked sheet materials. A sheet material loading device characterized by being configured to press a fixed number of sheets. 2. The sheet material stacking device according to claim 1, wherein the pressing force of the pressing member is set to a value that does not cause buckling of the last sheet material stacked when the sheet material is pressed. 3. The sheet material loading device according to claim 1, further comprising a tapered portion provided below the pressing portion of the holding member that presses the sheet material. 4. A sheet material stacking device including a presser member that presses side edges of stacked sheet materials to urge them toward a conveyance reference surface, wherein the presser member is provided so as to be movable in the sheet material stacking direction. A sheet material loading device characterized in that the holding member is provided with a pressing portion that presses a fixed number of sheet materials, and an abutting member that abuts the uppermost surface of the stacked sheet materials.