JPH01294133A - Sheet feeder - Google Patents

Abstract

PURPOSE:To make sheet feeding accurately performable even if the insertion of each sheet by manual operation or the like is not sufficient enough by installing a freely retractable projection in a sheet feeding member. CONSTITUTION:When a start key is pushed after a sheet S1 is inserted thereinto by manual operation or the like, a paper feeding member 1 gets rotating clockwise, and each of projections 10d, 10e comes into contact with this sheet S1. If this paper feeding member 1 is rotating in a arrow C direction, the sheet S1 is fed in an arrow D direction by dint of frictional force out of these projections 10d, 10e. When the paper feeding member 1 is further rotated, since an interval between these projections 10d, 10e and a topmost sheet S0 is narrowed, these projections 10d, 10e receive pressure from sheets S in a housing 3 via the sheet S1. However, since these projections 10d, 10e and an outer layer part 10 have elasticity each, these projections 10d, 10e are sunk in cavities 12, 13 installed at both sides of the paper feeding member 1, so that the sheet S1 receives frictional force of a friction member 10c from its whole surface and conveyed in the arrow D direction.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a sheet feeding device for feeding sheets in a copying machine, a laser beam printer, etc. The present invention relates to a sheet feeding device capable of feeding different sheets.

(Prior Art) Conventionally, there is a device of this type as shown in FIG. feed. That is, first, a paper feed member 104 for feeding the sheet lO1 is fixed to a drive shaft 103 driven by a drive means 102 such as a motor, and roller members 105 and 106 are attached to the drive shaft on both sides of the paper feed member 104. The sheet feed member 104 is rotatably attached around the drive shaft 103 and rotated by the rotation of the drive shaft 103.

Here, as shown in FIG.
A friction portion 104c having a high coefficient of friction and elasticity is provided around 4a, and the outer diameter of the roller members 105 and 106 is slightly smaller than the outer diameter of the arcuate portion 104a of the paper feeding member 104. Then, by rotating the paper feeding member 104 fixed to the drive shaft 103 in the direction of arrow A1, the frictional portion 104c is brought into contact with the uppermost sheet 101, and the sheet 101 is fed in the direction of arrow B1 by the frictional force. and send it to the conveying section 107.

In addition, when sending a sheet of a different type to the sheet 101 in the sheet storage box 100, as shown in FIG.
or another seat storage box (not shown)
The sheet separated from the sheet is automatically inserted onto the sheet 101, and the sheet 108 is fed by rotating the sheet feeding member 104 to bring the frictional portion 104C into contact with the sheet 108 as described above. It is said that

(Problem to be Solved by the Invention) However, in such a conventional example, when feeding a sheet 108 of a different type from the sheet 101 in the sheet storage box 100 by manual feeding, etc., the tip of the sheet 108 is As shown in FIG. 6(a), the roller members 105, 106
and the uppermost sheet 101 in the sheet storage box 100
Therefore, the leading end of the sheet 108 is always located upstream of the leading end of the sheet 101 in the feeding direction. Therefore, if a different type of sheet 10B is not inserted sufficiently by manual feeding or the like, the friction portion 104 of the sheet feeding member 104 may be damaged as shown in FIG. 6(b).
There have been cases where the sheet 108 slips and the sheet 108 cannot be fed even when the sheet feeding member 104 rotates, and the uppermost sheet 101 in the sheet storage box 100 is fed.

To solve this problem, as shown in FIG. 7, a paper stopper 109 is attached to the leading edge of the sheet to prevent the feeding of the sheet 101 in the sheet storage box lOO, thereby making it easier to manually feed the sheet. A method has also been devised to prevent mix-ups of feed sheets.

However, when attaching the paper stopper 109 to the sheet 101, it is necessary to take out the sheet storage box lOO each time, and this work is very complicated.
For devices equipped with a function to automatically feed paper from other storage boxes, only the operation of attaching the paper stopper 109 must be performed manually, so the original automatic paper feeding function cannot be achieved. It was extremely inconvenient.

Therefore, the present invention has been made to solve the problems of the prior art described above, and its purpose is to use a special stopper when feeding sheets other than the sheets in a predetermined sheet storage box. To provide a sheet feeding device capable of surely feeding sheets without at least causing feeding errors.

(Means for Solving the Problems) In order to achieve the above object, the present invention brings a movable sheet feeding member into pressure contact with the sheet to be fed, and moves the sheet feeding member to feed the sheet. The sheet feeding device is characterized in that the sheet feeding member is provided with a retractable protrusion that contacts the sheet and feeds out the sheet.

(Function) In the present invention having the above configuration, when feeding a sheet manually or the like, even if the position of the sheet deviates from a predetermined position to the upstream side in the feeding direction, the sheet Since the protrusion provided on the feeding member contacts the sheet and feeds it out, there is no possibility of accidentally feeding a sheet located below.

In addition, since this protrusion is provided so as to be able to appear and retract from the sheet feeding member, when the sheet feeding member and the sheet are brought into pressure contact, it may sink inward of the sheet filling member and obstruct sheet feeding. There isn't.

(Example) The present invention will be explained below based on illustrated embodiments.

FIG. 1 and FIGS. 2(a) and 2(b) show an embodiment of a sheet feeding device according to the present invention. In the same figure,
Reference numeral 1 denotes a sheet feeding member, which is a sheet feeding member, and is fixed to a drive shaft 2 connected to a drive source (not shown). This paper feeding member 1 consists of a substantially cylindrical hollow surface layer 10 and a substantially cylindrical core 11 press-fitted into the surface layer 10, and fixes this core 11 to the drive shaft 2. The core material 11 is shorter in length than the surface layer portion 10, and therefore, there are recesses 1 at both ends of the paper feeding member l.
2.13 is formed on the surface layer 10 made of an elastic member, and as shown in FIG. 1, the rotation center A of the drive shaft 2
It is composed of a circular arc portion 10a formed concentrically with respect to the circular arc portion and a connecting portion 10b formed inside the extension line of the circular arc. In this case, a friction member 10c having a coefficient of friction higher than the coefficient of friction between the sheet S and the seat 85 is attached to the surface of the arcuate portion 10a.
In c, two protrusions 10d and lOe are integrally formed at both ends of the surface of the circular arc portion 10a and at the position where the sheet is first fed out. Here, the surface layer 10 and the protrusion 10d,
Since the projection 10e has elasticity, the protrusion 10d, fo
When a force is applied to e toward the axis of rotation, as shown in Fig. 2 (b
), each protrusion 10d, toe is recessed 12°13
It is recessed to the side.

On the drive shaft 2 and on both sides of the paper feed member l, roller members 14.
15 is provided. The roller members 14, 15 have an outer diameter slightly smaller than the outer diameter of the circular arc portion 10a of the paper feeding member 1, and are used to smoothly feed the sheet material S.

Sheets S) are stacked and stored in a sheet storage box 3, and the sheet storage box 3 can be locked in a predetermined position so that the leading edge of the sheet s is located almost directly below the rotation axis A of the paper feed member 1. It becomes. This sheet S is urged upward by a spring 31 in the sheet storage box 3, so that the uppermost sheet (So) is in a predetermined position, and the uppermost sheet (S) is in a predetermined position.

Another sheet S+ can be inserted into a predetermined position into the gap between the sheet feeding member L and the sheet feeding member L by manual insertion or conveyance from another sheet storage box (not shown).

Near the sheet storage box 3 and on the downstream side of the paper feeding member 1, a friction member 4 is provided for transporting and separating the sheets S to be transported.
is provided on the paper feed guide 5, and the friction coefficient of the friction member 4 with respect to the sheet S is set to be smaller than the friction coefficient of the friction member 10c of the paper feed member 1 with respect to the sheet S, and larger than the friction coefficient between the sheets 85. It is. Note that a conveying section 6 consisting of a pair of rollers is provided on the downstream side of the sheet feeding guide 4 in the sheet conveying direction.

In the above configuration, as shown in FIG. 1, when a start key (not shown) is pressed with the sheet S1 manually inserted, etc., the paper feed member l starts rotating clockwise, and as shown in FIG. ), the projections 10d and 10e abut against the sheet S1.

Then, as the paper feeding member l rotates in the direction of arrow C, the sheet Sl is moved to the protrusions 10d and 1 as shown in FIG. 3(b).
The paper is fed in the direction of the arrow by the frictional force from 0e. When the paper feeding member l is further rotated in the same direction, each protrusion 10d
, 10e and the uppermost sheet) So, each protrusion 10d, foe receives pressure from the sheet S in the storage box 3 via the sheet s+.
Since each projection 10d, 10e and the surface layer lO have elasticity, each projection 10d, 10
The sheet (e) is depressed into the recesses 12.13 provided on both sides of the paper feeding member 1, and as a result, the sheet (st) is conveyed in the direction of the arrow by receiving a frictional force from the entire surface of the friction member 10c.

Thereafter, the sheet S+ is sandwiched between the friction members 10c and 4, but since the friction coefficient of the friction member 10c is larger than that of the friction member 4 as described above, both the friction members 10c and 4 are sandwiched between the friction members 10c and 4 via the While in pressure contact, a propulsive force acts on the sheet S+, and the sheet S1 is sent toward the conveyance section 6 via the paper feed guide 4.

After the leading end of the sheet S reaches the conveyance section 6, the conveyance section 6 is driven at a predetermined timing to send the sheet S1 to an image forming section (not shown).

As described above, in this embodiment, the sheet feeding member 1 is provided with the protrusions 10d, 10e, and the protrusions 10d, 10e are provided on the paper feeding member 1.
By making 0e freely retractable from the paper feeding member 1, the portions of the protrusions 10d and 10e are 3! It is closer to the sheet (S) St when manually fed or the like than other parts of the rubbing member 10c, and the position where the paper feed member 1 and the sheet (St) first come into contact is on the upstream side in the feeding direction compared to the conventional example. Even if the insertion is not sufficient, there is an effect that the sheet can be reliably fed without slipping between the sheet feeding member 1 and the sheet S1.

In addition, since it is possible to omit the work of removing the sheet storage box and attaching a paper stopper to prevent sheet feeding errors, it is possible to simplify the manual paper feeding operation, and to avoid the need to remove the sheet storage box and attach the paper stopper. When a sheet is automatically fed from a sheet, reliable sheet feeding can be achieved without performing the above operations, and there is also the effect that an automatic two-stage sheet feeding mechanism in the true sense can be provided.

In this embodiment, two protrusions for feeding out the sheet S+ are provided on the paper feed member l, but the present invention is not limited to this, and three or more protrusions may be provided. Furthermore, the positions where the protrusions are provided are not limited to the two ends of the paper feed member l as in the present embodiment, however, two protrusions 10d are provided at both ends of the paper feed member l as in the present embodiment.

If 10e is provided, it is symmetrical with respect to the sheet feeding direction, so there will be no misalignment when feeding out the sheet S+.Furthermore, since this part is a flexible part of the surface layer 10, the protrusion will not occur. 10d, the toe can be reliably dented.

Furthermore, the sheet feeding device according to the present invention is applicable not only to copying machines and laser beam printers, but also to all devices capable of feeding a sheet different from the sheet in the sheet storage box by one manual feeding or the like.

(Effects of the Invention) In the present invention having the above-described configuration and operation, since the sheet feeding member is provided with a protrusion that can freely appear and retract, the sheet can be fed even if the sheet is not fully inserted by manual feed or the like. This has the effect of being able to reliably perform the following steps.

In addition, since it is possible to omit the work of installing special parts to prevent sheet feeding errors, it is possible to simplify the manual feeding operation, and it is also possible to automatically feed sheets from other sheet storage boxes. There is also the advantage that when the paper is fed in a specific manner, the above-mentioned operation can be omitted and a true automatic two-stage paper feeding mechanism can be provided.

[Brief explanation of the drawing]

FIG. 1 is a schematic front view showing the structure of an embodiment of a sheet feeding device according to the present invention, FIG. 2(a) is a perspective view showing the structure of the paper feeding section of the same embodiment, and FIG. 2(b) FIG. 3(a) is a perspective view showing a state in which the protrusion is recessed in the paper feeding member of the same embodiment.
or C) is a schematic front view of the structure showing the sheet feeding operation in the same embodiment, FIGS. 4 and 5 show a conventional sheet feeding device, FIG. 4 is a perspective view, and FIG. 6(a) and 6(b) are schematic front views of the structure showing the paper feeding operation in the conventional device, and FIG. 7 is a front view of the schematic structure showing the paper feeding operation in the conventional device. FIG. Explanation of symbols 1... Paper feeding member (sheet feeding member) 10... Surface layer portion 10a... Arc portion 10c
...Friction members 10d, 10e...Protrusions 12.
13...Recesses S, So, Sl...Sheet patent applicant: Canon Co., Ltd. ；j・I Agent Patent Attorney Kazunobu Sera,, <j,
, +'; Figure 1 Figure 2 (σ) Chiku3 Figure ((7) , .

Claims (1)

[Scope of Claims] A sheet feeding device that brings a movable sheet feeding member into pressure contact with a sheet to be fed and feeds the sheet by moving the sheet feeding member, the sheet feeding member comprising: A sheet feeding device comprising a retractable protrusion that contacts the sheet and feeds out the sheet.