JPH08225174A - Paper feeder - Google Patents

Abstract

PURPOSE: To provide a paper feeder in which good operability is provided and a setting error can be prevented. CONSTITUTION: A paper feeder is provided with a paper feeding tray 3 on which paper is placed, a corner pawl fulcrum shaft 9 arranged on the axial line crossing perpendicularly to the paper feeding direction X of the paper feeding tray 3, and a corner pawl 11 which is supported freely oscillationally on the corner pawl fulcrum shaft 9 and presses the corner in the front part in the paper conveying direction X by means of its self-weight so as to separate the paper one by one. A sliding guide part 18 provided in the paper feeder is constructed of an engaging part 13 formed in the corner pawl 11 and an engaged part 14 formed in the paper feeding tray 3 and leads the corner pawl 11 to the normal position above the paper feeding tray 3 and to the outside of the paper width below the paper feeding tray 3.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art Paper feeders based on the corner claw separation system are
By pressing the stacked uppermost sheet by the weight of the corner claws, a corner claw blocking force is generated at the time of sheet feeding, and the sheet is separated and fed by this corner claw blocking force.

However, in this paper feeding device, when setting the paper in the paper feeding tray, the paper has to be set under the tapered portion of the corner claw, and therefore it takes a lot of time and labor to set the paper. It may damage the edges.

On the other hand, there is a sheet feeding device disclosed in Japanese Utility Model Publication No. 5-47148. This paper feeder supports the corner claws from below and sets the bottom plate that is urged upward by the spring in a depressed state when setting the paper in the paper feeding tray. It is designed to prevent the corner claws from swinging downward by preventing the corner claws from being pushed up. As a result, the gap between the tapered portion of the corner claw and the bottom plate is widened, and it becomes easier to set the paper under the tapered portion of the corner claw.

[0005]

However, in the paper feeding device disclosed in Japanese Utility Model Publication No. 5-47148, there is a corner claw at the position where the paper is set, so the paper is fed from directly above the paper feeding tray. Cannot be set. Therefore, there are problems that the operability is poor and that a set error is likely to occur.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a paper feeding device which has good operability and can prevent a setting error.

[0007]

According to the first aspect of the present invention,
A sheet feed tray for stacking sheets, a corner claw fulcrum shaft provided on an axis line orthogonal to the sheet feeding and conveying direction of the sheet feed tray, and swingably supported by the corner claw fulcrum shaft. A corner claw that separates the sheets one by one by pressing the front corner of the sheet in the sheet feeding and conveying direction by its own weight, an engaging portion formed on the corner claw, and an engaged portion formed on the sheet feeding tray. And a slide guide portion that guides the corner claws to a regular position above the paper feed tray and to the outside of the paper width below the paper feed tray.

According to a second aspect of the invention, the corner claw fulcrum shaft of the sheet feeding device according to the first aspect is provided with a screw portion for adjusting the position of the fulcrum of the corner claw.

According to a third aspect of the present invention, the corner claw fulcrum shaft of the sheet feeding device according to the first aspect is provided perpendicularly to the bottom surface of the sheet feeding tray with a play provided between the corner claw fulcrum.

[0010]

According to the first aspect of the invention, when the sheet is set in the sheet feeding tray, the sliding guide portion guides the corner claw swinging downward of the sheet feeding tray to the outside of the sheet width. Since there is no corner claw at the position to set, paper can be set from directly above the paper feed tray.

According to the second aspect of the invention, the angle of the corner claw can be adjusted by adjusting the position of the fulcrum of the corner claw with the screw portion, and the way the corner claw is applied can be changed. The corner claw blocking force can be adjusted according to the paper type, paper thickness and paper size.

According to the third aspect of the present invention, since the fulcrum of the corner claw does not shift to the outside of the paper width, the angle of the corner claw is kept constant, and the change in the amount of the corner claw is prevented. .

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described with reference to FIGS. The sheet feeding device 1 of this embodiment is applied to the copying machine 2. That is, in the paper feed tray 1 located at the lower part of the copying machine 2, the front loading type paper feed tray 3 is housed. The paper feed tray 3 is sized according to the size of the paper 4 to be fed. The paper feed tray 3 is provided with a bottom plate 6 which is supported at the rear and is urged upward by a spring 5 at the front in the paper feeding and conveying direction X so as to be rotatable by a predetermined angle. The sheets 4 of a certain size are stacked on the bottom plate 6. The trailing edge fence 7 is attached to the rear end of the sheet 4 around the sheet 4.
Is provided, and a pair of side fences 8 is provided at both left and right ends. Further, the paper feed tray 3 has corner claw fulcrum shafts 9 supported on the respective wall surfaces on the axis line orthogonal to the paper feed and conveyance direction X. A spring 10 is fitted to the corner claw fulcrum shaft 9, and a pair of corner claws 11 biased toward the sheet 4 by the spring 10 are swingably supported. And, the corner claw 11 is
It is arranged in front of the side fence 8 in the sheet feeding and conveying direction X. The corner claw 11 is formed with a tapered portion 12 in front of the uppermost sheet 4 in the sheet feeding and conveying direction X, and a guide protrusion 13 as an engaging portion is formed below the tapered portion 12. ing. A corner claw guide groove 14 into which the guide protrusion 13 is slidably fitted is formed in the paper feed tray 3. This corner claw guide groove 14
Is a vertical normal guide portion 15 formed above the sheet 4 side and a vertical normal guide portion 15 formed below the wall surface side of the paper feed tray 3 in the left-right direction of the sheet 4 and shorter than the normal guide portion 15. The outer guide portion 16 and the obliquely inclined guide portion 17 connecting the regular guide portion 15 and the outer guide portion 16 to each other.
It is formed by and. With the guide projection 13 and the corner claw guide groove 14, the corner claw 1 is made to approach the sheet 4 at the upper side and move away from the sheet 4 at the lower side.
Although the position of No. 1 is changed, the sliding guide portion 18 for guiding the corner claw 11 in this way is provided with the guide projection 1
3 and the corner claw guide groove 14.

In such a structure, the corner claw 11
Oscillates up and down on the front side in the sheet feeding and conveying direction X with the corner claw fulcrum shaft 9 as a fulcrum. And the regular guide section 15 is
The corner of the sheet 4 pushed up by the bottom plate 6 is tapered 12
The corner claws 11 are held in the proper positions so that they can be pressed. Further, the outer guide portion 16 has a sheet width L so that the taper portion 12 is located outside the position where the sheets 4 are stacked.
The corner claw 11 is held on the outer side of. Therefore, when the paper is fed, the corner claw 11 is pushed upward by placing the taper portion 12 on the paper 4, so that the guide projection 13 slides upward in the corner claw guide groove 14 and the regular guide is formed. The corner claw 11 is held in a regular position by the portion 15. Further, when the paper 4 is set in the paper feed tray 3, since the paper 4 is not under the taper portion 12, the corner claw 11 descends downward by its own weight. At this time, the guide projection 13 slides downward in the corner claw guide groove 14, and the corner claw 11 moves the sheet width L by the external guide portion 16.
Held outside of.

As described above, when the paper 4 is set in the paper feed tray 3, since the taper portion 12 is located outside the paper width L, the paper 4 can be set right above the paper feed tray 3. it can. Therefore, it is possible to obtain a paper feeding device that has good operability when setting the paper 4 and can prevent a setting error.

An embodiment of the invention described in claim 2 will be described with reference to FIGS. 5 and 6. The same parts as those described in the above-described embodiments are designated by the same reference numerals, and the description thereof will be omitted (the same applies to other embodiments below). The paper feed tray 3 is provided with a support portion 19 that supports the corner claw 11. The supporting portion 19 has holes 2
0 is formed. The corner claw fulcrum shaft 9 is inserted into the hole 20. The corner claw fulcrum shaft 9 is formed by screwing a screw 22, which is a screw portion, onto a corner claw fulcrum shaft body 21.

In such a structure, the screw 22 is screwed into the corner claw fulcrum shaft main body 21 more deeply or shallowly, so that the corner claw fulcrum shaft 9 is engaged.
The length of the corner claw 11 can be adjusted to adjust the position of the fulcrum of the corner claw 11. Therefore, as shown in FIG. 5, the fulcrum of the corner claw 11 is moved closer to the sheet 4 side, and the corner claw 1
1 can be supported in parallel to the sheet feeding / conveying direction X. Further, as shown in FIG. 6, the position of the fulcrum of the corner claw 11 can be moved away from the sheet 4 and the corner claw 11 can be tilted toward the sheet 4 side with respect to the sheet feeding / conveying direction X.

As described above, the taper angle between the taper portion 12 and the sheet 4 is adjusted by adjusting the position of the fulcrum of the corner claw 11 and inclining the corner claw 11 with respect to the sheet feeding and conveying direction X. Thus, it is possible to change how the tapered portion 12 is applied. Therefore, the corner claw blocking force can be adjusted according to the line type, the paper thickness, and the paper size of the paper 4, and the paper feeding performance for various kinds of paper is stabilized.

An embodiment of the invention described in claim 3 will be described with reference to FIGS. 7 and 8. A corner claw fulcrum shaft 9 is supported on the bottom surface of the paper feed tray 3 perpendicularly to the bottom surface. A spring 10 is fitted to the corner claw fulcrum shaft 9, and a corner claw 11 biased upward by the spring 10 is held with play.

According to this structure, the corner claw 11 is formed.
Has a fulcrum above the corner claw fulcrum shaft 9 and is swingably supported downward by its own weight. Therefore, when the paper 4 is set in the paper feed tray 3, the guide projection 13 slides downward in the corner claw guide groove 14, and the tapered portion 12 is located outside the paper width L. This allows
Paper can be set right above the paper feed tray 3. Further, since the corner claw fulcrum shaft 9 is provided perpendicularly to the bottom surface of the sheet feed tray 3, the rear end of the corner claw 11 in the sheet feeding / transporting direction X may be displaced in the left / right direction due to impact or the like after setting the sheet 4. Absent. Therefore, the corner claws 11 are kept constant in the sheet feeding / conveying direction X, the change in the amount applied due to an impact or the like is prevented, and the sheet feeding performance at the time of sheet feeding is stabilized.

[0021]

According to the first aspect of the present invention, when the paper is set in the paper feed tray, the sliding guide portion guides the corner claw swinging downward of the paper feed tray to the outside of the paper width. Since there are no corner claws at the position where the paper is set, it is possible to set the paper even directly above the paper feed tray, the operability when setting the paper is good, and it is possible to prevent setting mistakes. A paper machine can be obtained.

According to a second aspect of the invention, in addition to the effect of the first aspect of the invention, the angle of the corner claw is adjusted by adjusting the position of the fulcrum of the corner claw with a screw portion to adjust the corner claw. Since the way it is applied can be changed, the corner claw blocking force can be adjusted according to the paper type, paper thickness and paper size, and the paper feeding performance can be stabilized for a wide variety of paper. it can.

According to the invention of claim 3, in addition to the effect of the invention of claim 1, by providing a corner claw fulcrum shaft perpendicular to the bottom surface of the paper feed tray, the fulcrum of the corner claw corresponds to the paper width. Since there is no deviation to the outside, the angle of the corner claw can be kept constant, the change in the amount of the corner claw can be prevented, and the sheet feeding performance at the time of sheet feeding can be stabilized.

[Brief description of drawings]

FIG. 1 is a perspective view showing a part of a paper feed tray according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a copying machine provided with the paper feeding device.

FIG. 3 is a vertical side view showing a paper feed tray.

FIG. 4 is a plan view thereof.

FIG. 5 is a plan view showing a part of a paper feed tray according to an embodiment of the present invention.

FIG. 6 is a plan view showing another state of the paper feed tray.

FIG. 7 is a perspective view showing a part of a paper feed tray according to an embodiment of the invention as set forth in claim 3;

FIG. 8 is a side view thereof.

[Explanation of symbols]

 3 Paper Tray 4 Paper 9 Corner Claw Support Shaft 11 Corner Claw 13 Engagement Part 14 Engaged Part 18 Sliding Guide Part 22 Screw Part

Claims (3)

[Claims] 1. A paper feed tray on which sheets are stacked, a corner claw fulcrum shaft provided on an axis line orthogonal to the paper feeding and conveying direction of the paper in the paper feed tray, and swingable about the corner claw fulcrum shaft. A corner claw that is supported by the sheet and presses the front corner of the sheet in the sheet feeding / conveying direction by its own weight to separate the sheet one by one; and an engaging portion formed on the corner claw and the sheet feeding tray. And a slide guide portion that guides the corner claw to a regular position above the paper feed tray and to the outside of the paper width below the paper feed tray. Paper feeder. 2. The sheet feeding device according to claim 1, wherein the corner claw fulcrum shaft is provided with a screw portion for adjusting the position of the fulcrum of the corner claw. 3. The sheet feeding device according to claim 1, wherein the corner claw fulcrum shaft is provided perpendicularly to the bottom surface of the sheet feeding tray with a play provided between the corner claw fulcrum.