JP3192052B2 - Sheet separation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotator for supply, 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 coefficient of friction between the sheets.

[0002]

2. Description of the Related Art As a conventional sheet separating apparatus of this type, for example, there is one as shown in FIG.

That is, a plurality of stacked sheets 1
The supply rotating body 101 that is pressed against the uppermost sheet 100a of No. 00 and the supply rotating body 101 is pressed against the lower sheet so that only the uppermost sheet 100a can be separated and supplied by applying frictional resistance to the lower sheet. Separation member 102
And

After the uppermost sheet 100a is separated and supplied, the lower sheet 100b becomes the uppermost sheet 10a.
As shown in FIG. 6B, a separation assisting member 104 having a 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 feeding.
And

[0005] The separation assisting member 104 has a passage closing position A where the sheet abutting portion 103 projects into the sheet passage.
The uppermost sheet 100a can be moved to the passage opening position B when separated and supplied, and moved to the passage closed position A after separation and supply. .

[0006]

However, in the above-described conventional example, the pressing portion 106 located on the opposite side of the separation assisting member 104, the sheet abutting portion 103 and the rotation center 105 is interposed.
Is pushed down by a middle plate 107 on which the sheets 100 are stacked, thereby rotating the separation assisting member 104, and the raised sheet abutting portion 103 blocks the paper path to prevent double feeding of the lower sheet. 104 is merely pushed down by the middle plate 107 and its position is away from the sheet abutting portion 103.
However, there is a problem that it is difficult to prevent the double feed from being caused because the position of the surface where the sheet abuts is difficult to obtain and the position varies.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art. It is an object of the present invention to accurately position the position of the sheet abutting portion of the separation assisting member at the passage closing position. It is another object of the present invention to provide a sheet separating apparatus capable of reliably preventing double feeding.

[0008]

In order to achieve the above object, according to the present invention, there is provided a supply rotating body pressed against the uppermost sheet of a plurality of stacked sheets, and the supply rotating body. A separating member that is pressed against the lower sheet and applies a frictional resistance to the lower sheet so that only the uppermost sheet can be separated and supplied, and the lower sheet is separated and supplied after the uppermost sheet is separated and supplied. A separation abutting portion having a sheet abutting portion against which the lower sheet leading end abuts so as not to be double fed. A sheet separating apparatus which is movable between two positions, a passage opening position for opening a sheet passage and a passage opening position when the uppermost sheet is separated and supplied, and moves to a passage closed position after separation and supply. , The maximum sea of the rotation axis of the supply rotary member
Positioning rollers provided at positions outside the
For positioning provided on the separation auxiliary member that engages with the positioning roller
And a positioning mechanism for positioning the sheet abutting portion at the passage closing position of the separation assisting member.

[0009] The pressure contact between the supply rotating body and the sheet is as follows.
The sheet stacking section for stacking sheets is movable, and the sheet stacking member is configured to press the sheet against the supply rotating body.

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 rotating body for feeding, and the separating member is moved in conjunction with the movement of the sheet stacking member. characterized in that to separate from the rotating body.

[0011] Further, the present invention is characterized in that the separation assisting member is movable in conjunction with the sheet stacking member.

[0012]

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

Further, a positioning mechanism, Runode provided between the positioning rollers provided outside the maximum sheet width of the rotational shaft of the supply rotary member and the separation assisting member, the positional relationship between the supply rotary member Determined exactly.

Further, a movable sheet stacking member is provided, and in conjunction with the sheet stacking member, after separating and feeding the uppermost sheet, the sheet is separated from the supply rotating body, and the separation member is also separated from the supply rotating body. By doing so, the previous sheet is not affected, and the conveying force is not applied to the lower sheet. The only force acting on the lower sheet is the frictional force with the uppermost sheet. In this state, the sheet passage is closed by the separation assisting member, so that the double feeding of the sheet can be reliably prevented.

[0015]

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

Reference Example First, a reference example will be described. 1 to 3 show a sheet separating apparatus according to a reference example .

That is, on the main body frame 1 of the sheet separating apparatus, an intermediate plate 3 as a stacking member for stacking a plurality of sheets 7, a separation pad 4 as a separating member for separating a plurality of sheets, A sub-pad 2 serving as a separation assisting member that closes a paper path serving as a sheet passage is pivotally supported by a stepped sheet abutting portion 2b that prevents double feeding of sheets.

At a position facing the middle plate 3 and the separation pad 4, a paper feed roller 5 as a supply rotating body is 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 separating pressure, respectively, are held on the main body frame 1 on the back surfaces of the intermediate plate 3 and the separating pad 4.

On the other hand, on both sides of the separation pad 4 of the main body frame 1 and in the thrust direction thereof, guide ribs 1b as sheet guide portions for guiding the sheet 7 are provided at substantially equal intervals. The projection 2d as a positioning stopper provided on the side of the subpad 2 abuts against the back surface 1a of the eaves 1c of the rib 1b constituting the stopper engaging portion, and the position of the sheet abutting portion 2b of the subpad 2 is adjusted. Is configured to be surely output. The protrusion 2d and the rib 1b
The eaves portion 1c constitutes a positioning mechanism of the reference example .

On the downstream side in the transport direction of the paper feed roller 5, a transport roller 11 for transporting the sheet 7 sent by the paper feed roller 5, and a transport roller 1 pressed against the transport roller 11.
0 is provided. Before sheet feeding, the plurality of sheets 7 stacked on the middle plate 3 are opposed to the pushing-up force of the middle plate pressing spring 8 by a cam to which power is transmitted by a drive unit (not shown), as shown in FIG. Then, the upper sheet is pushed down to a position where it is separated from the paper feed roller 5. The separation pad 4 is located at a position where the back tension is not applied to the sheet 7a fed by the middle plate 3,
That is, the rib 1b of the main body frame 1 serving as the seat guide surface
It has been pushed down to a lower position.

When the middle plate contact portion 2c having elasticity of the sub pad 2 is pushed down by the middle plate 3, the sub pad 2 rotates about the rotation center 2a. Then, the convex portion 2d serving as a stopper on the side surface of the sub pad 2 abuts against the back surface 1a of the eave portion 1c of the rib 1b of the main body frame 1, and the position is determined by the deformation of the middle plate contact portion 2c. 2b stops at the position shown in FIG. At this time, since the convex portion 2d is provided near the sheet abutting portion 2b, the position is easily determined. The front sheet 7a conveyed by the conveyance rollers 11 and the conveyance rollers 10 can pass through, but the next sheet 7b hits the sheet abutting portion 2b and cannot pass.

At the time of sheet feeding, first, as shown in FIG. 2, a large number of sheets 7 stacked on the middle plate 3 are rotated by a cam, to which power is transmitted by a drive unit (not shown). Becomes free and is pushed up by the middle plate pressing spring 8.

The middle plate 3 stops at a position where a large number of sheets 7 on the middle plate 3 abut against the 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 a pad pressing spring 9 and stops at a position where the separation pad 4 comes into contact with the sheet feeding roller 5. The subpad 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), and the sheet feeding roller 5 starts rotating in the sheet feeding direction (clockwise direction in the figure), and feeds out the uppermost one 7a of the multiple sheets 7. . At this time, the friction coefficient between the sheet feeding roller 5 and the sheet 7a is higher than the friction coefficient between the uppermost sheet 7a and the lower next sheet 7b.
Has a high coefficient of friction, the top sheet
It is paid out 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 pairs 10, 11 and the paper feed roller 5. At this time, the transport roller pairs 10, 11 and the paper feed roller 5 are set to have substantially the same transport speed.

When the paper feed roller 5 makes one rotation, 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. Reaches the passage closing position, blocks the paper path, and prevents the next sheet 7b from passing through.

The paper feed roller 5 is also provided on the separation pad 4 with the middle plate 3.
The front sheet 7a is not pressed against
And only by the transport roller 10.

In the reference example , a convex portion 2d as a positioning stopper is provided near the sheet abutting portion 2b of the subpad 2, while the guide rib 1b of the main body frame 1 is provided.
The convex portion 2d is engaged with the eave portion 1c which is a concave portion, but the sub pad 2 is provided with a concave portion as a positioning stopper, and the guide rib 1b has a convex portion engaging with the concave portion. Of course, it is good.

[Embodiment ] In the above reference example , the positioning of the sub pad 2 is performed only on the main body frame 1 side.
If the sheet is outside the maximum width of the sheet to be fed (for example, 210 mm or more for A4), the sheet abutting portion of the subpad 2 is passed through the positioning roller 12 through the sheet feeding roller shaft 6 as shown in FIGS. By abutting the roller 2b against the roller 12, the positional accuracy of the paper feed roller 5 and the subpad 2 can be improved.

4 and 5, the same components as those of the above-mentioned reference example are denoted by the same reference numerals, and description thereof will be omitted.
In the actual施例this, similarly to the reference examples, Yes and loading a plurality of sheets on intermediate plate 3, the intermediate plate 3 which is pushed down by a not-shown cam, the cam by a drive system (not shown) When driven, as shown in FIG. 2, the intermediate plate 3 rotates about the rotation center 3a, and presses the sheet feed roller 5 and the sheet 7 into contact. The sheet 7 is fed one by one by the paper feed roller 5 rotating in the clockwise direction, passes over the separation pad 4, and the leading end of the sheet 7 a is conveyed by the conveying roller 11 and the conveying roller 10.
To reach.

When the paper feed roller 5 makes one rotation, the intermediate plate 3 is pushed down by a cam (not shown), and the separation pad 4 is also pushed down in conjunction therewith. On the other hand, the sub pad 2
The roller 12 is pushed up by the middle plate 3, and abutting on the roller 12 on the paper feed roller shaft 6, the position of which is determined. At this time, since the rollers 12 are provided outside the maximum sheet width, the rollers 12 do not become a load for conveying the front sheet 7a by the conveying rollers 11 and the conveying rollers 10.

As shown in FIG. 5, the front sheet 7a is transported by the transport roller 11 and the transport roller 10, and the subpad 2 is positioned by the roller 12 on the paper feed roller shaft 6. Position accuracy with the upper paper feed roller 5 can be easily obtained. The next sheet 7b collides with the sheet abutting portion 2b of the subpad 2 and is not sent while being overlapped with the previous sheet 7a.

[0033]

As described above, according to the present invention,
The separation assisting member for preventing double feeding, the rotation axis of the supply rotary member
Positioning cogs located outside the maximum sheet width of
(B) provided on the separation assisting member engaging with the positioning roller.
By providing a positioning mechanism composed of a positioning abutting portion and a simple structure, it is possible to obtain positional accuracy at the passage closing position with a simple configuration, and to reliably prevent double feeding in which the preceding sheet and the next sheet are fed and overlapped. There is an effect that can be.

[Brief description of the drawings]

FIG. 1 is a main cross-sectional view illustrating a standby state of a sheet separating apparatus according to a reference example .

FIG. 2 is a main cross-sectional view illustrating a sheet feeding state of a sheet separating apparatus according to a reference example .

FIG. 3 is a plan view illustrating a standby state of a sheet separating apparatus according to a reference example .

It is a plan view showing a standby state of the sheet separating device of the real施例of the present invention; FIG.

5 is a main cross-sectional view showing a standby state of the sheet separating device of the real施例of the present invention.

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body frame 1a Back surface 2 Sub pad (separation auxiliary member) 2a Sub pad rotation center 2b Sub pad sheet abutting portion 2c Sub pad middle plate contact portion 2d Sub pad projection 3 Middle plate 3a Rotation center of middle plate 4 Separation pad 4a Rotation center of separation pad 5 Paper feed roller (rotating body for supply) 6 Paper feed roller shaft 7 Sheet 7a Previous sheet 7b Next sheet 8 Middle plate pressing spring 9 Pad pressing spring 10 Transport roller 11 Transport roller 12 (for sub pad contact) Roller

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Seiichiro Kadota 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (56) References JP-A-4-350033 (JP, A) JP-A Heihei 5-4732 (JP, A) JP-A-2-66533 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B65H 1/00-3/68

Claims (4)

(57) [Claims] 1. A supply rotating body pressed against an uppermost sheet of a plurality of stacked sheets, and an uppermost sheet pressed against the supply rotating body to impart frictional resistance to a lower sheet, thereby providing an uppermost sheet. A separating member that allows only the sheets to be separated and fed, and a sheet striking position in which the lower sheet leading edge is struck so that the lower sheet is not taken over by the uppermost sheet after the upper sheet is separated and fed. A separation assisting member having a portion, wherein the separation assisting member is movable between two positions: a passage closing position where the sheet abutting portion projects into the sheet passage, and a passage opening position where the sheet passage is opened. In the sheet separation device that moves to the passage open position when the topmost sheet is separated and fed, and moves to the passage closed position after separation and feeding, it is located outside the maximum sheet width of the rotating shaft of the rotating body for feeding.
The provided positioning roller and engaging with the positioning roller
Consists of a positioning abutment provided on the separation assisting member
And a positioning mechanism for positioning the position of the sheet abutting portion at the passage closing position of the separation assisting member. 2. The press-contact between a supply rotating body and a sheet is characterized in that a sheet stacking member for stacking sheets is made movable, and the sheet is pressed against the supply rotating body by the sheet stacking member. The sheet separating apparatus according to claim 1. 3. A structure in which a sheet stacking member is moved in a direction in which a sheet is separated from a supply rotating body after separation and supply of a top sheet, and the sheet stacking member is moved in conjunction with the movement of the sheet stacking member. sheet separating apparatus according to claim 2, characterized in that to separate from the rotating body. 4. The sheet separating apparatus according to claim 3, wherein the separation auxiliary member is movable in conjunction with the sheet stacking member.