JP2002068492A - Paper feeding device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a locating mechanism for sheet stacking tray capable of reducing the cost and enhancing the maintenance easiness and also appearance. SOLUTION: When the sheet stacking tray 1 is set in a paper feeding device, a locating member 36 positioned behind the tray 1 in its setting direction is inserted in another locating member 35 on the frame side of the paper feeding device so that the location is established; and when the tray 1 is set at the upper stage, a locating member 32 on the tray 1 side is fitted to a locating member 31 on the device side, and when the tray 1 is set at the lower stage, a locating member 34 on the tray 1 side is fitted to a locating member 33 on the device side, and thus the locations in the horizontal directions perpendicular to the setting and removing directions are established.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying machine, a printer,
The present invention relates to a sheet feeding device of an image forming apparatus such as a facsimile.

[0002]

2. Description of the Related Art In a sheet feeding device used in an image forming apparatus such as a copying machine, a printer, a facsimile or the like, a sheet stacking tray (sheet feeding cassette) for stacking and storing sheets of paper and the like and sending out the sheets from the sheet stacking tray. Feed mechanism up and down 2
There is a type in which a sheet stacking tray having the same shape can be mounted on the upper and lower tiers.

In order to position these sheet stacking trays in the sheet feeding device main body in a horizontal direction orthogonal to the direction in which the sheet stacking trays are inserted, a partition is provided between the upper and lower stages in the sheet feeding device, and The stacking tray is positioned with the positioning member provided on the partition, and the lower sheet stacking tray is positioned with the positioning member provided on the bottom plate of the sheet feeding device or a member corresponding thereto so that the same sheet stacking tray can be used. There is a configuration in which the positioning member can be attached to the lower stage, or a configuration in which positioning members are provided at the left and right ends of the opening for inserting the sheet stacking tray of the sheet feeding device.

For example, as a specific configuration of the former conventional example, as shown in FIG. 6, a partition 40 is provided between upper and lower openings of a sheet feeding device, and a positioning member 33 is provided there. Further, as a specific configuration of the latter conventional example, as shown in FIG. 7, positioning members 37 are provided on the left and right sides of the opening of the sheet stacking tray 1 mounting portion, and the right and left ends of the sheet stacking tray 1 are provided. This is for positioning.

[0005]

However, the above prior art has the following problems.

In the configuration in which the partition is provided, there is a problem that the cost for the partition is increased, and it becomes difficult to access the hand during maintenance of the paper feeding mechanism, for example, when replacing a rubber roller. In addition, in the configuration in which positioning is provided on the left and right sides of the opening, the sheet stacking tray and the sheet feeding device can be easily pryed when the device for detaching the sheet stacking tray is located away from the positioning, such as in the center. Since the distance from the positioning to the right and left ends is different, the right and left will differ due to the effects of thermal expansion, etc.
There was a risk that the appearance would be impaired.

[0007]

In order to solve the above-mentioned problems, the present invention provides a sheet stacking tray of the same shape for stacking sheets in an opening provided in a main body of a sheet feeding device so as to be mountable in two upper and lower stages. A sheet feeding device provided with sheet feeding means for feeding a sheet from each sheet stacking tray, wherein a positioning member is provided on each of an upper side and a lower side of the sheet stacking tray, and an upper side of an opening of the sheet feeding main body. And a positioning member for engaging with a positioning member of the sheet stacking tray provided on a lower side, and a sheet stacking tray mounted on the upper side of the opening includes a positioning member provided on an upper side of the sheet stacking tray and an upper portion of the opening. The sheet stacking tray is positioned by engaging with a positioning member provided on the side of the sheet stacking tray. Digit positioning member and the positioning member which is provided on the lower side of said opening engages, characterized in that positioning the sheet stacking tray.

According to the present invention, one of the positioning member on the sheet stacking tray side and the positioning member on the opening side has a projecting shape, and the other has a U-shape or a concave shape. The sheet loading tray can be positioned.

According to the present invention, a back positioning member is provided on a back side in a mounting direction of the sheet stacking tray, and a positioning member for engaging the back side positioning member is provided on a sheet feeding device main body. It is characterized by performing positioning on the back side in the direction.

The present invention is characterized in that a handle portion is provided on a drawer side of the sheet stacking tray, and the positioning member is provided on an upper side just above the handle portion.

In the present invention, the sheet feeding means feeds the sheet in a direction orthogonal to a mounting direction of the sheet stacking tray.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a schematic configuration of a laser beam printer having a paper feeder according to the present invention will be described with reference to FIG.

The printer A stores sheets S of, for example, A4 and A3 sizes, and stores the sheets S on the front side of the printer body (FIG. 1).
A sheet stacking tray 1 which is detachably mounted from a direction perpendicular to the paper surface of FIG. 1, and a direction perpendicular to the tray mounting direction (right direction in the figure) by a pick-up roller 2 from the sheet stacking tray 1 in which a selected sheet is stored. ) To feed the sheet.

Sheets fed by the pickup roller 2 are separated and fed one by one by a retard separation mechanism including a feed roller 3A rotating in the sheet feeding direction and a retard roller 3B rotating in the direction opposite to the sheet feeding direction. Is done.

The sheets which are separated and fed one by one are conveyed to a pair of registration rollers 5 by a conveyance roller 4 and synchronized with image formation by the registration rollers 5 to form image forming means 6.
Transported to

The image forming means 6 is provided with a charging means, a developing means and a cleaning means (not shown) around the photosensitive drum 7. After the charging means uniformly charges the surface of the photosensitive drum 7, a laser A latent image is formed by selective exposure by the scanner 8, and the latent image is developed into a visible image by developing with toner. Then, a transfer bias voltage is applied to the transfer roller 9 to transfer the toner image onto the conveyed sheet to form an image, and the toner remaining on the photosensitive drum 7 after the transfer is removed by a cleaning unit. These image forming means are formed into cartridges, and by replacing the process cartridge B,
The toner can be supplied, and maintenance of the photosensitive drum and the like is not required.

Sheet fixing means 10 to which the toner image has been transferred
When the toner image passes through the pair of fixing rollers, heat and pressure are applied to fix the toner image. The toner image is conveyed by the discharge rollers 11 and 12 and discharged to the discharge unit 13.

FIG. 2 is a view of the printer A as viewed obliquely from the front and above. The sheet stacking tray 1 has horizontal regulating plates 21A and 21B for regulating the position of the stored sheets in the width direction.
And a rear end regulating plate 22 for regulating the position of the rear end of the sheet. The sheet stacking tray 1 is movable in a direction indicated by an arrow in the drawing, which is orthogonal to the sheet feeding direction, and can be attached to and detached from the sheet feeding device.

A U-shaped positioning member 32 is provided on the upper side of the sheet stacking tray 1 on the front side in the drawing direction of the sheet stacking tray and directly above the handle for pulling out the sheet stacking tray 1. The lower side is provided with a U-shaped positioning member 34 as shown in FIG. Further, a protruding positioning member 36 is provided on the back side in the mounting direction of the sheet stacking tray 1 as shown in FIG.

As shown in FIG. 3, the sheet feeder is provided with protruding positioning members 31 and 33 above and below the entrance of the opening in which the sheet stacking tray 1 is mounted, and the opening is viewed from the front. As shown in the figure, a positioning member 35 having a concave shape is provided on the frame of the sheet feeding device at the back side of the opening.

With this configuration, when the sheet stacking tray 1 is mounted on the sheet feeding device, the positioning member 36 on the back side in the mounting direction of the sheet stacking tray 1 is inserted into the positioning member 35 on the frame side of the sheet feeding device. Is positioned and also
When the sheet stacking tray 1 is mounted on the upper side, the positioning member 32 on the sheet stacking tray 1 is fitted to the positioning member 31 on the sheet feeding device side, and when the sheet stacking tray 1 is mounted on the lower side, sheet feeding is performed. The positioning member 34 on the sheet stacking tray 1 is fitted to the positioning member 33 on the apparatus side, and positioning in the horizontal direction orthogonal to the mounting / removing direction is performed.

The shapes of the positioning members may be reversed. That is, for example, the positioning member 31 may have a U shape or a concave shape, and the positioning member 32 may have a projection shape.

As a result, the sheet stacking tray 1 is accurately mounted at a proper position of the sheet feeding device, so that sheet feeding defects such as sheet feeding defects and sheet separation defects can be reduced. It is possible to prevent a decrease in image forming accuracy such as displacement from the position. By adopting the configuration of the present invention, the partition 40 is provided between the upper and lower openings as in the conventional example shown in FIG. 6, and the positioning member 33 is provided there. Since there is no partition 40 at the time of maintenance such as replacement of the 3A and the retard roller 3B, there is an advantage that work from the opening can be easily performed and the cost of the partition 40 is reduced.

As in the conventional example shown in FIG. 7, a positioning member 37 is provided on the left and right sides of the opening of the sheet stacking tray 1 mounting portion to perform positioning at the left and right ends of the sheet stacking tray 1. The positioning member generates a rotational moment that causes twisting when attaching and detaching the sheet stacking tray 1 when a hand-holding portion for performing attachment / detachment operation of the sheet stacking tray is located away from the positioning, such as the center of the width of the sheet stacking tray 1. Providing 31 and 33 near the handle makes it easier to avoid, and the distance to the positioning of the left and right ends of the exterior portion of the sheet stacking tray 1 is substantially the same as the width of the sheet stacking tray 1. Positioning members 31 and 33 also tend to be out of alignment with the exterior of other paper feeders due to thermal expansion, dimensional tolerances, and the like.
Is arranged near the center of the width of the sheet stacking tray 1.

The present invention is not limited to the configuration of the above-described embodiment. For example, the positioning member may be formed by inserting a projecting member into a concave member or fitting a positioning member into a U-shaped member. However, the shape is not limited to this, and any shape may be used as long as the movement of the mounted sheet stacking tray in the left-right direction is restricted.

[0026]

As described above, according to the present invention, in a paper feeder in which two upper and lower sheet stacking trays can be mounted, an increase in cost for the positioning structure of the sheet stacking tray can be suppressed, and further, maintenance can be performed. This has the effect of improving sex and beauty.

[Brief description of the drawings]

FIG. 1 is a configuration explanatory view of a laser beam printer according to an embodiment of the present invention.

FIG. 2 is a perspective view of the laser beam printer and a sheet stacking tray shown in FIG.

FIG. 3 is a perspective view showing a state where a sheet stacking tray is removed in the laser printer shown in FIG. 2;

FIG. 4 is a front view of the laser beam printer shown in FIG.

5 is a perspective view of the sheet stacking tray shown in FIG. 1 from below.

FIG. 6 is a perspective view showing a positioning member in a conventional sheet feeding device.

FIG. 7 is a perspective view of a positioning member in another conventional sheet feeding device.

[Explanation of symbols]

 Reference Signs List A laser beam printer B process cartridge S sheet 1 sheet stacking sheet stacking tray 2 pickup roller 3A feed roller 3B retard roller 4 transport roller 5 registration roller 6 image forming means 7 photosensitive drum 8 laser scanner 9 transfer roller 10 fixing means 11, 12 Discharge roller 13 Discharge portion 21A, 21B Width regulating plate 22 Rear end regulating plate 31-37 Positioning member 40 Partition

Claims (6)

[Claims] A sheet stacking tray of the same shape for stacking sheets is provided in an opening provided in a sheet feeding device main body so as to be mountable in two upper and lower stages, and sheet feeding means for sending out a sheet from each sheet stacking tray is provided. A sheet feeding device, wherein a positioning member is provided on each of an upper side and a lower side of the sheet stacking tray, and a positioning member that engages with a positioning member of the sheet stacking tray on an upper side and a lower side of an opening of the sheet feeding main body. The sheet stacking tray provided with a member is mounted on the upper side of the opening, and the positioning member provided on the upper side of the sheet stacking tray engages with the positioning member provided on the upper side of the opening. Position, the sheet stacking tray mounted below the opening,
A sheet feeding device, wherein a positioning member provided on a lower side of the sheet stacking tray and a positioning member provided on a lower side of the opening are engaged to position the sheet stacking tray. 2. A positioning member on the side of the sheet stacking tray and a positioning member on the side of the opening have a protruding shape, and the other has a U-shape or a concave shape. The sheet feeding device according to claim 1, wherein the tray can be positioned. A positioning member provided on a back side in a mounting direction of the sheet stacking tray, and a positioning member engaged with the back side positioning member is provided on a sheet feeding device main body; The sheet feeding device according to claim 1, wherein positioning of the side is performed. 4. The sheet feeding device according to claim 1, wherein a handle portion is provided on a drawer side of the sheet stacking tray, and the positioning member is provided on an upper side just above the handle portion. 5. The sheet feeding device according to claim 1, wherein the sheet feeding unit feeds the sheet in a direction orthogonal to a mounting direction of the sheet stacking tray. 6. A sheet feeding device according to claim 1, further comprising: an image forming unit that forms an image on a sheet fed from the sheet feeding device. Image forming device.