JPH07330183A - Sheet separating device - Google Patents

Abstract

PURPOSE:To separate or feed the paper of different thickness under the optimum condition by securing the optimum separating condition according to the thickness of the paper only by the simple, compact and light structure. CONSTITUTION:A paper separating device is provided with a paper feeding roller 1, a friction plate 3 to be pressed against this paper feeding roller 1 by a spring 4, and a carrying table 5 to be pressed against the paper feeding roller 1 side by the spring 6, and a plurality of paper sheets 2 loaded on this carrying table 5 are separated and carried one by one. An angle adjusting mechanism consisting of a rotary shaft 3c formed on the end part of the side opposite to the side where the spring 4 of the friction plate 3 is abutted and a pivotably supported part 8 provided with an adjusting groove 8a with which this rotary shaft 3c is slidably engaged are provided, and the crossing angle of a friction part 3a of the friction plate 3 with the loading surface of the paper 2 of the carrying table 5 is adjusted by moving this rotary shaft 3c in the adjusting groove 8a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a separating mechanism for feeding cut sheets in a printing device such as a printer or a copying machine, and more particularly to a sheet separating device capable of improving the separation accuracy of both thick paper and thin paper. Regarding the device.

[0002]

2. Description of the Related Art A sheet separating device for separating and feeding single-cut sheets one by one in a printing device such as a printer or a copying machine is roughly classified into an adsorption separation system and a friction separation system. Of these, a friction member is installed in the paper path, and the friction coefficient between the paper feed roller and the paper, the mutual friction coefficient between the paper,
Also, the friction separating method for separating the sheets one by one according to the relationship between the friction coefficient between the sheet and the friction member can make the structure simple and lightweight, and has relatively few paper feeding mistakes. Widely used as a paper feed mechanism for various printing equipment.

A conventional paper separating apparatus using a friction separating method will be described with reference to the drawings. FIG. 5 is a side sectional view of an essential part showing a sheet separating apparatus adopting a conventional general friction separating method. As shown in FIG. 1, a conventional sheet separating apparatus using a friction separating method includes a sheet feeding roller 1, a sheet 2 for sheet feeding, and a friction plate including a friction member that is pressed against the sheet feeding roller 1 by a spring 4. 3, a carrying table 5 for stacking and holding the sheets 2, a spring 6 for pressing the carrying table 5 upward (toward the paper feed roller 1), and a base 7 for holding and fixing these parts. .

In the conventional sheet separating apparatus having such a structure, the sheet feeding roller 1 presses and rotates the uppermost sheet 2a of the sheet 2 to move it forward (to the left in the drawing), and at the same time, the second and subsequent sheets are fed. In this case, the friction plate 3 blocks the forward movement of the sheet, and the sheets are separated one by one and fed to a printer or the like.

In this conventional sheet separating device, the friction coefficient between the sheet 2 and the friction plate 3 is set based on the mutual friction coefficient between the sheets so that the friction plate 3 can surely prevent the second and subsequent sheets from advancing. So that the
Each part is formed so that the friction coefficient between the paper 2 and the paper feed roller 1 is larger than that.

That is, the uppermost sheet 2a of the sheet 2 sent out by the sheet feeding roller 1 is further pushed forward without being prevented from advancing by the friction plate 3, and the second and subsequent sheets are rubbed by the friction plate 3. Is blocked from moving forward. As a result, the sheets 2 are sequentially sent out one by one from the uppermost sheet 2a and fed to a device such as a printer (not shown). An example of a technique that employs this type of paper separating device is an automatic paper feeding device described in Japanese Utility Model Laid-Open No. 62-71137.

However, in the conventional sheet separating apparatus having such a structure, the sheet to be fed is
For example, when postcards and copy paper, etc., which have different thicknesses are mixed, the friction coefficient of the paper is not constant, so that the balance of the friction coefficient between the paper feed roller, the friction plate, and the paper cannot be maintained. However, there is a problem that it becomes difficult to separate and feed the paper under the best condition as described above.

Conventionally, in such a case, in order to prevent paper feeding and conveyance mistakes, the paper feeding roller and the friction plate are delicate so as to be able to deal with papers having different thicknesses, that is, friction coefficients. This was dealt with by setting the frictional force. Therefore, as a result, the coefficient of friction between the respective parts is set to an intermediate value of the coefficient of friction under the optimum separation conditions as described above, and rather, paper feeding, conveyance errors, etc. of each sheet occur. Was there.

In order to solve such a problem, in Japanese Utility Model Laid-Open No. 2-112637, a cam-shaped roller is pressed against a base to which a friction pad (plate) is fixed, and the cam-shaped roller is pressed. A friction separating mechanism of an automatic paper feeding device has been proposed in which the base is pressed by rotating the roller, and thereby the pressing force of the friction pad on the paper feeding roller can be adjusted.

According to the paper feeding apparatus described in this publication, the cam-shaped roller is rotated in accordance with the thickness of the paper to be fed to adjust the pressing force of the friction pad against the paper feed roller. It is possible to set the separation condition corresponding to, and thereby prevent the occurrence of a paper feed error or the like as in the prior art.

[0011]

However, in the friction separating mechanism disclosed in Japanese Utility Model Laid-Open No. 2-112637, the support member for supporting the friction pad must be fixed to the base, which is why It is difficult to obtain parallelism between the paper roller and the friction pad (longitudinal direction of the paper feed roller), and the frictional force between the friction pad and the paper feed roller in the longitudinal direction of the paper feed roller becomes non-uniform, causing a conveyance error. there were.

In the friction separating mechanism disclosed in Japanese Utility Model Laid-Open No. 2-112637, even when the thickness of the sheet is different, the sheet is sent out by following the conveying path at a constant angle, so that it is particularly suitable for postcards. Even in the case of thick paper, the paper is bent and conveyed as in the case of thin paper, and as a result, an excessive torque is applied to the driving means of the paper feed roller as a load and the paper is curved. Occurred.

Further, the friction separating mechanism described in this publication is
A separate structure is required, such as a cam-shaped roller, a rotating shaft that supports the cam-shaped roller, and fixing means for press-contacting these with the base, resulting in an increase in the number of parts compared to the conventional one, and an increase in the size and weight of the entire device. There was also the problem of becoming

The present invention has been proposed in order to solve the problems of each of the conventional techniques described above, and the optimum separation condition according to the thickness of the sheet can be obtained only by the simple, small and lightweight structure. It is an object of the present invention to provide a sheet separating device that secures and separates and feeds sheets of different thickness under optimal conditions.

[0015]

In order to achieve the above object, a sheet separating device of the present invention is provided with a sheet feeding roller, a friction plate pressed against the sheet feeding roller by a pressing member, and a sheet feeding roller side by a pressing member. A sheet separating device for separating and conveying a plurality of sheets stacked on the conveying table one by one, which has a conveying table that is pressed against the friction table of the friction plate and a sheet stacking surface of the conveying table. Is provided with an angle adjusting mechanism capable of adjusting the intersecting angle of, and preferably, the angle adjusting mechanism is provided on a side of the friction plate or the conveying plate where the pressing member abuts with the shaft supporting portion having the adjusting groove. And a rotary shaft which is formed at the opposite end and slides in the adjustment groove. Further, it is more preferable that a step portion is formed in the adjustment groove of the shaft support portion, and if necessary, the rotating shaft is configured to be slidably held in the adjustment groove by a ball screw. The screw is rotated by a pulse motor.

[0016]

According to the sheet separating apparatus of the present invention having the above structure, when the sheet to be fed is thick, the friction portion of the friction plate and the sheet stacking surface of the conveying table are adjusted by adjusting the angle of the friction plate or the conveying table. Increase the angle of intersection with (close to horizontal)
However, when the thickness of the sheet is thin, the angle of the friction plate or the transport base is adjusted in the same manner to reduce the intersecting angle between the friction portion of the friction plate and the sheet stacking surface of the transport base. The coefficient of friction with respect to the paper can be changed according to the thickness of the paper to be fed, so that it is possible to effectively prevent paper feeding, conveyance error, and the like.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the sheet separating apparatus of the present invention will be described below with reference to the drawings. FIG. 1 is a side sectional view of an essential part showing a first embodiment of a sheet separating device of the present invention,
(A) shows a state where thick paper is targeted, and (b) shows a state where thin paper is targeted.

As shown in the figure, in the paper separating apparatus of this embodiment, a paper feed roller 1, a paper 2 for feeding paper, and a friction portion which is pressed against the paper feed roller 1 by a spring 4 as a pressing member. A friction plate 3a having 3a, a carrier 5 for stacking and holding the sheets 2 substantially horizontally, a spring 6 as a pressing member for pressing the carrier 5 upward (toward the paper feed roller 1), and each of these. It comprises a base 7 for holding and fixing members.

The upper surface of one end of the uppermost paper 2a of the paper 2 is pressed against the outer peripheral lower surface of the paper feed roller 1 which conveys the paper 2 by the rotation and frictional force. The sheets 2 are stacked and held on the surface of the conveyance table 5, and the conveyance table 5 is elastically ejected by a spring 6 as a pressing member provided on the lower surface of the sheet 2 in the conveyance direction. It is always pressed upwards (feed roller side) with force. As a result, the paper 2 is
The uppermost paper 2a is always pressed against the lower surface of the outer circumference of the paper feed roller 1.

The friction plate 3 is composed of a friction portion 3a made of a friction member and a support portion 3b for supporting the friction portion 3a. The friction plate 3 is arranged below the paper feed roller 1 and on the paper conveyance direction side of the conveyance table 5. ing. In the friction plate 3, the friction portion 3a is in pressure contact with the lower portion of the paper feed roller 1, and the end on the paper 2 side is in contact with one end of the uppermost paper 2a of the paper 2.

A spring 4 as a pressing member fixed to a base 7 is arranged on the lower surface of the support portion 3b on the side of the sheet 2 and the plate 3 is provided by the spring 4.
Are always pressed against the paper feed roller 1 side with a constant elastic force. As a result, the friction portion 3a of the friction plate 3 is always in pressure contact with the lower portion of the paper feed roller 1.

Further, the friction plate 3 has a support portion 3
An angle adjusting mechanism is provided so that one end of b can be moved. The angle adjusting mechanism allows the carrier 5 of the friction plate 3 to move.
With respect to, that is, the friction portion 3a of the friction plate 3
It is possible to freely adjust the intersecting angle θ between the sheet and the stacking surface of the sheet 2 on the transport table 5. In this embodiment, as shown in FIG. 1, this angle adjusting mechanism is provided with shaft support portions 8 having adjustment grooves 8a fixed to the base 7 on both sides of the friction plate 3 and the inside of the adjustment grooves 8a. A sliding rotary shaft 3c is provided at the end of the support portion 3b on the paper transport direction side, that is, at the end of the friction plate 3 opposite to the side where the spring 4 abuts.
It is configured by moving the inside of a in the vertical direction (the direction of the arrow in FIG. 1).

That is, when the rotary shaft 3c moves upward, the angle θ of the friction plate 3 with respect to the carrier table 5 becomes large, and when it moves downward, it becomes small (see FIG. 1). When the rotary shaft 3c moves upward, the rotary shaft 3c is engaged with and fixed to the step portion 8b formed at the upper end of the adjustment groove 8a, so that the adjustment angle of the friction plate 3 does not shift. . Further, the rotation shaft 3c may be fixed in the adjustment groove 8a by forming a screw at the end of the rotation shaft 3c and tightening a nut on the screw portion to fix the rotation shaft 3c in the adjustment groove 8a. .

Next, the operation of the sheet separating apparatus of this embodiment having the above structure will be described. First, when the paper 2 to be fed is thick paper, the rotary shaft 3c is moved downward (see FIG.
1A), the paper 2 and the friction plate 3 are moved as shown in FIG. 1A.
Increase the angle θ of. In this way, the friction coefficient between the friction plate 3 and the paper 2 is reduced, that is, by adjusting to the conditions for separating thick paper, it is possible to effectively prevent picking mistakes and the like that tend to occur with thick paper.

When the thickness of the paper 2 to be fed is small, the rotary shaft 3c is moved upward (in the direction of arrow B in FIG. 1 (b)) to move the paper as shown in FIG. 1 (b). The angle θ between 2 and the friction plate 3 is reduced. In this way, the coefficient of friction between the friction plate 3 and the paper 2 is increased, that is, by adjusting to the separation condition of thin paper,
It is possible to prevent a paper feed error such as a double feed that tends to occur when using thin paper.

Next, a second embodiment of the paper separating device of the present invention will be described with reference to FIG. FIG. 2 is a side sectional view of a main part of the sheet separating device according to the present embodiment.
Shows a state where thick paper is targeted, and (b) shows a state where thin paper is targeted. As shown in the figure, in the present embodiment, the carrier table 5 on which the sheets are stacked is provided with an angle adjusting mechanism whose one end is movable, and the angle of the carrier table 5 with respect to the friction plate 3, that is, the carrier The intersection angle θ between the stacking surface of the paper 2 on the table 5 and the friction portion 3a of the friction plate 3 can be freely adjusted.

In the angle adjusting mechanism of this embodiment, as shown in FIG. 2, the shaft support 9 having the adjusting groove 9a is formed in the base 7.
The rotary shaft 5a which is provided in the adjusting groove 9a and slides in the adjusting groove 9a is provided at an end portion of the conveying table 5 opposite to the sheet conveying direction, that is, an end portion of the conveying table 5 opposite to the contact side of the spring 6. The rotary shaft 5a is configured to move in the vertical direction (in the direction of the arrow in FIG. 2) in the adjustment groove 9a.

That is, the rotary shaft 5a is downward (see FIG. 2).
When moved in the direction of arrow A in (a), the angle θ of the carriage 5 with respect to the friction plate 3 increases, and decreases in the direction of upward (direction of arrow B in FIG. 2B). (See FIG. 2). As a result, the same effects as in the case of the first embodiment can be obtained also in the paper separating apparatus of this embodiment.

Next, a third embodiment of the paper separating device of the present invention will be described with reference to FIG. FIG. 3 is a side view showing the angle adjusting mechanism of the sheet separating apparatus in this embodiment. As shown in the figure, in the present embodiment, at least one position of the adjustment groove 9a of the shaft support 9 in the above-described first and second embodiments (the drawing is the case of the second embodiment),
A step portion 9c with which the rotary shaft 3c is engaged is formed. In this way, by forming the step portion 9c in the adjustment groove 9a,
The angle between the friction plate 3 and the conveyance table 5 can be adjusted in at least three stages, and the angle adjustment suitable for the type of the paper 2 can be performed. Note that this step portion can be provided with an arbitrary number of steps as necessary.

Next, a fourth embodiment of the paper separating device of the present invention will be described with reference to FIG. FIG. 4 is a partial plan view showing the angle adjusting mechanism of the sheet separating apparatus in this embodiment. As shown in the figure, in the present embodiment, in the angle adjusting mechanism of the first and second embodiments described above (the drawing shows the case of the first embodiment), along the adjustment groove 8a of the shaft support portion 8. The screw 10a of the ball screw 10 is provided, and the nut 10b screwed to the screw 10a is fixedly provided at the end of the rotary shaft 3c. By rotating the screw 10a of the ball screw 10 by the pulse motor 11, The rotating shaft 3c is configured to be slidably held in the adjusting groove 8a.

In this way, the rotary shaft 3c is attached to the ball screw 1
By holding it movably by 0, the angle between the friction plate 3 and the carrier table 5 can be continuously adjusted, and the adjustment work becomes easy. Although the screw 10a is rotated by the pulse motor 11 in this embodiment, the invention is not limited to this, and it may be manually rotated by, for example, a dial. In this case, the pulse motor 11
Since the device is not provided, the device structure can be simplified and the weight can be reduced.

The paper separating apparatus of the present invention is not limited to the above embodiment, and various modifications can be made within the scope of the invention. For example, in the above embodiment,
Although the angle adjusting mechanism is provided on only one of the friction plate and the carrier, it is also possible to provide this on both. In this case, since the angle can be adjusted from either the friction plate or the carrier, the work efficiency can be improved.

[0033]

As described above, according to the paper separating apparatus of the present invention, only the simple, small and lightweight structure is provided.
Optimal separation conditions can be secured according to the paper thickness, and papers of different thickness can be separated and fed under the optimum conditions.

[Brief description of drawings]

FIG. 1 is a side sectional view of an essential part showing a first embodiment of a sheet separating device of the invention, FIG.
(B) shows a state in which thin paper is targeted.

FIG. 2 is a side sectional view of an essential part showing a second embodiment of the paper separating apparatus of the present invention, in which (a) is a state in which thick paper is targeted,
(B) shows a state in which thin paper is targeted.

FIG. 3 is a side view showing an angle adjusting mechanism in a third embodiment of the sheet separating device of the invention.

FIG. 4 is a partial plan view showing an angle adjusting mechanism in a fourth embodiment of the sheet separating device of the invention.

FIG. 5 is a perspective view showing a side cross-sectional view of a main part of a sheet separating apparatus adopting a conventional general friction separating method.

[Explanation of Codes] 1 ... Paper Feed Roller 2 ... Paper 2a ... Top Paper 3 ... Friction Plate 3a ... Friction Part 3b ... Supporting Part 3c ... Rotation Shaft 4 ... Spring 5 ... Conveyor 5a ... Rotation Shaft 6 ... Spring 7 ... base 8 ... shaft support 8a ... adjustment groove 8b ... step portion 9 ... shaft support 9a ... adjustment groove 9b ... step portion 9c ... step portion 10 ... ball screw 10a ... screw 10b ... nut 11 ... pulse motor

Claims (6)

[Claims] 1. A paper feed roller, a friction plate that is pressed against the paper feed roller by a pressing member, and a carrier table that is pressed toward the paper feed roller by the pressing member, and a plurality of sheets are stacked on the carrier table. A sheet separating device for separating and conveying the sheets of paper one by one, wherein an angle adjusting mechanism for adjusting an intersecting angle between a friction portion of the friction plate and a sheet stacking surface of the conveying table is provided. Paper separation device. 2. The rotation adjusting mechanism, wherein the angle adjusting mechanism is formed on a shaft supporting portion having an adjusting groove and an end portion of the friction plate opposite to a side where the pressing member abuts, and sliding in the adjusting groove. The sheet separating device according to claim 1, wherein the sheet separating device comprises a shaft. 3. The angle adjusting mechanism is formed at a shaft supporting portion having an adjusting groove and an end portion of the carrying base opposite to a side where the pressing member abuts, and slides in the adjusting groove. The sheet separating apparatus according to claim 1, wherein the sheet separating apparatus comprises a rotary shaft formed at an end of the transport table. 4. The sheet separating apparatus according to claim 2, wherein a step portion is formed in the adjustment groove of the shaft support portion. 5. The sheet separating apparatus according to claim 2, 3 or 4, wherein the rotating shaft is slidably held in the adjusting groove by a ball screw. 6. The sheet separating apparatus according to claim 5, wherein the ball screw is rotated by a pulse motor.