JPH0881078A - Sheet separating device - Google Patents

Abstract

PURPOSE: To surely prevent overlapping feed by precisely positioning the position of a sheet abutting part of an auxiliary separating member at a path blocking position. CONSTITUTION: A resilient intermediate panel abutting part 2c of a subpad 2 pushes up an intermediate panel 3 so that the subpad 2 turns about a shaft 2a. A protrusion 2d serving as a stopper at one side surface of the subpad 2 abuts against the rear surface of a brim part 1c of a rib 1b of a body frame 1 so that the intermediate panel and the abutting part 2c are deformed to determine its position, and accordingly, a sheet abutting part 2b comes to a stop. In this arrangement, since the protrusion 2d is provided around the sheet abutting surface 2b, the position can be easily determined. With this arrangement, a foregonging sheet 7a transferred by a transfer roller 11 and a transfer roll 10 can pass, but a next sheet 7b abuts against the sheet abutting part 2b so that it cannot pass. Thereby, it is possible to prevent overlapping feed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding apparatus, a separating member, and a sheet separating apparatus such as a copying machine or a printer for feeding sheets one by one according to the difference in friction coefficient between the sheets.

[0002]

2. Description of the Related Art A conventional sheet separating apparatus of this type is shown in FIG.

That is, a plurality of stacked sheets 1
No. 00 of the supply roller 101 pressed against the uppermost sheet 100a, and by being pressed against the supply roller 101 to impart frictional resistance to the lower sheet, only the uppermost sheet 100a can be separately supplied. Separation member 102
And

After the uppermost sheet 100a is separated and supplied, the lower sheet 100b is the uppermost sheet 10a.
As shown in FIG. 6B, the separation assisting member 104 having the sheet abutting portion 103 against which the leading end of the lower sheet 100b is abutted so as not to be double-fed due to the sheet 0a.
And

The separation assisting member 104 includes a passage closing position A where the sheet abutting portion 103 projects into the sheet passage,
It is movable between two positions, that is, a passage opening position B that opens the sheet passage, and moves to the passage opening position B when the uppermost sheet 100a is separated and supplied, and to the passage closed position A after the separated supply. .

[0006]

However, in the above-mentioned conventional example, the pressing portion 106 located on the opposite side with the separation assisting member 104, the sheet abutting portion 103 and the rotation center 105 interposed therebetween.
Is pushed down by the middle plate 107 on which the sheets 100 are stacked to rotate the separation assisting member 104, and the raised sheet abutting portion 103 blocks the paper path to prevent double feeding of lower sheets. The sheet 100 is simply pushed down by the middle plate 107, and its position is far from the sheet abutting portion 103.
There is a problem in that it is difficult to reliably prevent the double feed because the position of the surface abutting against is difficult to obtain and the position varies.

The present invention has been made to solve the above-mentioned problems of the prior art, and its object is to accurately position the sheet abutting portion of the separation assisting member at the passage closing position. And to provide a sheet separating device that can reliably prevent double feeding.

[0008]

In order to achieve the above object, according to the present invention, a supply rotary member which is pressed against the uppermost sheet of a plurality of stacked sheets, and the supply rotary member. When the uppermost sheet is separated and supplied, the lower sheet is the uppermost sheet after the uppermost sheet is separated and supplied by being pressed against the lower sheet and imparting frictional resistance to the lower sheet. A separation assisting member having a sheet abutting portion against which a lower sheet tip is abutted so as not to be double-fed, and the separation assisting member has a passage blocking position where the sheet abutting portion protrudes into the sheet passage. A sheet separating device that can move between two positions, that is, a passage opening position for opening a sheet passage, moves to a passage opening position when separating and feeding the uppermost sheet, and moves to a passage closing position after separating and feeding. , Characterized in that a positioning mechanism for positioning the position of the sheet abutting portion in the passage closing position of the separation assistant member.

Further, the positioning mechanism is composed of a positioning portion provided in a guide portion for guiding the sheet and a positioning abutting portion engaging with the positioning portion provided in the vicinity of the sheet abutting portion of the separation assisting member. It is characterized by

Further, the positioning mechanism includes a positioning roller provided at a position outside the maximum sheet width of the rotary shaft of the supply rotary member, and a positioning abutting portion provided on the separation assisting member engaging with the positioning roller. It is composed of and.

The pressure contact between the supply rotary member and the sheet is
It is characterized in that a sheet stacking unit for stacking sheets is movable, and the sheet stacking member presses the sheet against the supply rotary member.

Further, after the uppermost sheet is separated and supplied, the sheet stacking member is moved in a direction in which the sheet is separated from the supply rotary member, and the separating member is supplied in association with the movement of the sheet stacking member. It is characterized by being separated from the rotating body.

Further, the separation assisting member is movable in conjunction with the sheet stacking member.

[0014]

According to the present invention, since the position of the sheet abutting portion is positioned by the positioning mechanism at the passage blocking position of the separation assisting member, the variation in the position of the sheet abutting portion can be suppressed.

In particular, if the positioning mechanism is performed by the positioning portion and the positioning abutting portion provided in the vicinity of the sheet guiding portion and the sheet abutting portion, the positional relationship with the sheet guiding portion is accurately determined. The positional relationship of is also accurately determined.

If the positioning mechanism is provided between the positioning roller provided outside the maximum sheet width of the rotation shaft of the supply rotary member and the separation assisting member, the positional relationship with the supply rotary member is maintained. Exactly determined.

Further, a movable sheet stacking member is provided, and in cooperation with the sheet stacking member, after separating and supplying the uppermost sheet, the sheet is separated from the supply rotating body, and the separating member also separates the supply rotating body. By doing so, the preceding sheet is not affected and the conveying force is not applied to the lower sheet. The force acting on the lower sheet is only the frictional force between the lower sheet and the uppermost sheet, and in this state, the separation assist member closes the sheet passage, so that the double feeding of sheets can be reliably prevented.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to illustrated embodiments.

1 to 3 show a sheet separating device according to a first embodiment of the present invention.

That is, on the main body frame 1 of the sheet separating apparatus, the intermediate plate 3 as a stacking member for stacking a plurality of sheets 7, the separation pad 4 as a separating member for separating a plurality of sheets, and the subordinate At the step-like sheet abutting portion 2b that prevents the sheets from being fed in double, the sub pad 2 as a separation assisting member that closes the sheet path as the sheet path is pivotally supported.

At a position facing the middle plate 3 and the separation pad 4, a paper feed roller 5 as a supply rotary member is pivotally supported by a side plate of the main body frame 1 via a paper feed roller shaft 6.
Springs 8 and 9 for applying a sheet feeding pressure and a separation pressure are held on the main body frame 1 on the back surfaces of the middle plate 3 and the separation pad 4, respectively.

On the other hand, on both sides of the separation pad 4 of the main body frame 1 and on the thrust direction thereof, guide ribs 1b as sheet guide portions for guiding the sheet 7 are provided at substantially equal intervals. Then, the convex portion 2d provided as a positioning stopper provided on the side portion of the subpad 2 abuts on the back surface 1a of the eave portion 1c of the rib 1b forming the stopper engaging portion, and the position of the sheet abutting portion 2b of the subpad 2 is positioned. Has been configured to ensure that. This convex portion 2d and rib 1b
The eaves portion 1c constitutes the positioning mechanism of the present invention.

On the downstream side of the sheet feeding roller 5 in the sheet conveying direction, a sheet conveying roller 11 for conveying the sheet 7 sent by the sheet feeding roller 5, and a sheet conveying roller 1 pressed against the sheet conveying roller 11.
0 is provided. Before feeding, the plurality of sheets 7 stacked on the middle plate 3 are opposed to the pushing force of the spring 8 by a cam to which power is transmitted by a drive unit (not shown), as shown in FIG. The upper sheet is pushed down to the position where it is separated from the paper feed roller 5.
The separation pad 4 is pushed down to a position where no back tension is applied to the sheet 7a fed by the middle plate 3, that is, a position lower than the rib 1b of the main body frame 1 which serves as a sheet guide surface.

By pushing down the elastic middle plate contact portion 2c of the sub pad 2 with the middle plate 3, the sub pad 2 rotates about the shaft 2a. And the sub pad 2
The convex portion 2d serving as a stopper on the side surface of the main body 1 abuts against the back surface 1c of the eave portion 1c of the rib 1b of the main body frame 1, and the intermediate plate abutting portion 2c is deformed to determine the position. It stops at the position shown in 1. At this time, since the convex portion 2d is provided in the vicinity of the sheet abutting surface 2b, the position is easily determined. Although the front sheet 7a conveyed by the conveying roller 11 and the conveying roller 10 can pass,
The next sheet 7b abuts against the sheet abutting portion 2b and cannot pass through.

At the time of paper feeding, first of all, a large number of sheets 7 stacked on the intermediate plate 3 are rotated by a cam which is transmitted with power by a drive unit (not shown) as shown in FIG. Becomes free and is pushed up by the middle plate pressing spring 8.

The middle plate 3 is stopped at a position where a large number of sheets 7 on the middle plate 3 hit the paper feed roller 5. At this time, the separation pad 4 and the sub pad 2 are also free. The separation pad 4 is pushed up by the pad pressing spring 9 and stops at the position where it hits the paper feed roller 5. The sub pad 2 stops at a position lower than the rib 1b of the main body frame 1 due to its own weight.

On the other hand, the driving force is transmitted to the sheet feeding roller 5 by a driving unit (not shown), the sheet feeding roller 5 starts to rotate in the sheet feeding direction (clockwise direction in the figure), and the uppermost one sheet 7a of the multi-sheets 7 is fed out. . At this time, the coefficient of friction between the sheet feeding roller 5 and the sheet 7a is higher than the coefficient of friction between the uppermost sheet 7a and the lower next sheet 7b, and the separation pad 4 and the next sheet 7b.
Has a high coefficient of friction, so 1 from the top of the multiple sheets 7
It is delivered one by one.

When the leading end of the sheet 7a reaches the transport roller 11 and the transport roller 10, it is transported by the transport roller pair 10, 11 and the paper feed roller 5. At this time, the conveying roller pairs 10 and 11 and the paper feeding roller 5 are set to have substantially the same conveying speed.

When the paper feed roller 5 rotates once, the intermediate plate 3 is pushed down by a cam (not shown), and the separation pad 4 is pushed down to a position lower than the rib 1b of the main body frame 1 as shown in FIG. The sheet abutting portion 2b reaches the passage closing position to block the paper path and prevent the next sheet 7b from passing.

The paper feed roller 5 includes the separation pad 4 and the middle plate 3.
Since it is not pressed against the front sheet 7a,
And is conveyed only by the conveying roller 10.

In the above embodiment, the convex portion 2d as a positioning stopper is provided in the vicinity of the seat abutting portion 2b of the sub pad 2, and the guiding rib 1b of the main body frame 1 is provided.
The convex portion 2d is adapted to engage with the eaves portion 1c which is a concave portion, but the concave portion is provided on the subpad 2 as a positioning stopper, and the guiding rib 1b has a convex portion which engages with the concave portion. Of course, it is good. [Embodiment 2] In the first embodiment, the sub-pad 2 is positioned only on the body frame 1 side, but if it is outside the maximum width of the sheet to be fed (for example, 210 mm or more at A4), As shown in FIGS. 4 to 5, the paper feed roller shaft 6
Then, by abutting the sheet abutting portion 2b of the subpad 2 on the roller 12 through the positioning roller 12,
It is possible to improve the positional accuracy of the paper feed roller 5 and the sub pad 2.

In FIGS. 4 and 5, the same components as those in the above embodiment are designated by the same reference numerals and the description thereof will be omitted.
In the second embodiment, as in the first embodiment, a plurality of sheets are stacked on the intermediate plate 3, and the intermediate plate 3 pushed down by a cam (not shown) is moved by a drive system (not shown). The cam is driven to rotate the rotating shaft 3a as shown in FIG.
The center plate 3 rotates around the center and presses the paper feed roller 5 and the sheet 7 against each other. The sheets 7 are fed one by one by the sheet feeding roller 5 which rotates in the clockwise direction, pass over the separation pad 4, and the leading end of the sheet 7a reaches the conveyance roller 11 and the conveyance roller 10.

When the paper feed roller 5 rotates once, the intermediate plate 3 is pushed down by a cam (not shown), and the separation pad 4 is also pushed down in conjunction with it. On the other hand, the sub pad 2
It is pushed up by the middle plate 3 and hits the roller 12 on the paper feed roller shaft 6 to determine the position. At this time, since the rollers 12 are provided outside the maximum sheet width, the rollers 12 do not become a load for the conveyance roller 11 and the conveyance rollers 10 to convey the front sheet 7a.

As shown in FIG. 5, the front sheet 7a is conveyed by the conveying roller 11 and the conveying roller 10, and the sub pad 2 is positioned by the roller 12 on the sheet feeding roller shaft 6, so that the same sheet feeding roller shaft 6 is used. The positional accuracy with the upper paper feed roller 5 is easy to obtain. The next sheet 7b does not hit the sheet abutting surface 2b of the sub pad 2 and is not overlapped with the front sheet 7a and fed.

[0035]

As described above, according to the present invention,
By providing a positioning mechanism on the separation assisting member that prevents double feeding, it is possible to obtain position accuracy at the passage blocking position with a simple configuration and to reliably prevent double feeding in which the preceding sheet and the next sheet are overlapped and fed. There is an effect that can be done.

[Brief description of drawings]

FIG. 1 is a main cross-sectional view showing a standby state of a sheet separating device embodying the present invention.

FIG. 2 is a main cross-sectional view showing a sheet feeding state of a sheet separating apparatus embodying the present invention.

FIG. 3 is a plan view showing a standby state of the sheet separating apparatus embodying the present invention.

FIG. 4 is a plan view showing a standby state of the sheet separating apparatus according to another embodiment of the present invention.

FIG. 5 is a main cross-sectional view showing a standby state of a sheet separating apparatus according to another embodiment of the present invention.

FIG. 6 is a diagram showing a standby state and a sheet feeding state of a conventional sheet separating apparatus.

[Explanation of symbols]

 1 Main Frame 1a Frame Positioning Stopper 2 Sub Pad (Separation Auxiliary Member) 2a Sub Pad Rotation Center 2b Sub Pad Seat Abutting Part 2c Sub Pad Middle Plate Contact Part 2d Sub Pad Positioning Stopper 3 Middle Plate 3a Middle Plate Rotation Center 4 Separation Pad 4a Separation Pad Rotation Center 5 Paper Feed Roller (Rotating Body for Supply) 6 Paper Feed Roller Shaft 7 Sheet 7a Previous Sheet 7b Next Sheet 8 Middle Leaf Spring 9 Separation Pad Spring 10 Transport Roller 11 Transport Roller 12 (For Sub Pad Abutment) Coro

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Seiichiro Kadhira 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (6)

[Claims] 1. A supply rotary member which is pressed against the uppermost sheet of a plurality of stacked sheets, and a top rotary member which is pressed against the supply rotary member and imparts frictional resistance to a lower sheet. Separation member that allows only sheets to be separated and fed, and after the uppermost sheet is separated and fed, the lower sheet end is abutted so that the lower sheet is stuck to the uppermost sheet and is not double fed. A separation assisting member having a portion, wherein the separation assisting member is movable between two positions of a passage closing position in which the sheet abutting portion projects into the sheet passage and a passage opening position in which the sheet passage is opened, In a sheet separating device that moves to the passage opening position when separating and supplying the uppermost sheet, and moves to the passage closing position after separating and supplying, the sheet abutment of the separation assisting member at the passage closing position. Sheet separating apparatus characterized in that a positioning mechanism for positioning the position. 2. The positioning mechanism comprises a positioning stopper provided in the vicinity of the sheet abutting portion of the separation assisting member, and a stopper engaging portion provided in the sheet guide portion with which the positioning stopper engages. The sheet separating apparatus according to claim 1, wherein the sheet separating apparatus is configured. 3. The positioning mechanism includes a positioning roller provided at a position outside a maximum sheet width of a rotation shaft of a supply rotary member, and a positioning abutting portion provided on a separation assisting member engaging with the positioning roller. The sheet separating apparatus according to claim 1 or 2, comprising: 4. The pressure contact between the supply rotary member and the sheet is made such that a sheet stacking member for stacking the sheet is movable and the sheet is pressed against the supply rotary member by the sheet stacking member. The sheet separating device according to 2 or 3. 5. The sheet stacking member is configured to be moved in a direction in which the sheet separates from the supply rotator after the topmost sheet is separated and supplied, and the separation member is supplied in association with the movement of the sheet stacking member. The sheet separating device according to claim 4, wherein the sheet separating device is separated from the rotating body. 6. The sheet separating apparatus according to claim 5, wherein the separation assisting member is movable in conjunction with the sheet stacking member.