JPH0532332A - Sheet feed device - Google Patents

Abstract

PURPOSE:To eliminate the need of a back fence in manual sheet feed by returning an overlapped sheet only for cassette sheet feed in the system wherein cassette and manual sheet feeds are made in the same sheet feed passage. CONSTITUTION:When a cassette is set in a common sheet feed passage, an electromagnetic clutch 104 is turned on, upon sheet feed, and each roller is caused to rotate in a sheet feed direction, thereby feeding sheets from the cassette. Thereafter, the electromagnetic clutch 104 is turned off, and a feed roller 101 and a separation roller 122 are reversed by the predetermined number of rotations. In addition, a pickup roller 115 retreats due to the operation of a solenoid, and an overlapped sheet is thereby prevented from returning to the cassette. When a manual sheet feed table is set, a sheet is similarly fed therefrom. In this case, the pickup roller 115 is locked with the solenoid and a unidirectional clutch 114, and pressed to the sheet, thereby preventing the sheet from returning to the table.

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 for cassette feeding and manual feeding in the same feeding path in a copying machine or the like.

[0002]

2. Description of the Related Art As a paper feeding device of this type, a friction separating roller system having a feed roller rotating in the paper feeding direction and a separate roller paired with the feed roller and driven in reverse through a torque limiter is known. It is well known.
In this system, for example, the sheets accumulated and stored in the cassette are sequentially sent from the top to the nip part of the feed roller and the separate roller by the pull feed roller. It is configured to feed one sheet at a time.

In such a friction separation roller system, since the multi-fed paper is separated at the nip portion between the feed roller and the separate roller, the sheet left after separation is held in the nip portion. Sometimes. If the same paper feed is subsequently performed in this case, the remaining paper is also fed and no trouble occurs. By the way, when the cassette is pulled out by changing the paper size, the paper sandwiched in the nip portion remains as it is, and there is a problem that so-called residual paper occurs. For this reason, if the cassette is reattached without noticing the remaining paper, the paper is not only broken but also causes paper jam. Further, in the case of a mechanism in which cassette feeding and manual feeding are performed in the same feeding path, if the above-mentioned remaining paper is generated, even if an attempt is made to feed paper of different size and paper type by manual feeding, There was a problem that the paper was fed first and miscopy occurred.

Therefore, as a method of solving the problem of the residual paper of the friction separation roller system described above, the paper sandwiched in the nip portion of the feed roller and the separate roller by temporarily reversing the feed roller after the paper feeding. It has been proposed that the paper be returned to the paper storage unit.

[0005]

However, in the above-mentioned conventional method of removing the residual paper by reversing the feed roller, when the paper is returned, the accumulated paper in the accommodating section is pushed in the direction opposite to the paper feeding direction. There is a risk of deviation from the proper position and a delay in the paper feed timing, causing a paper feed failure. Therefore, it is necessary to provide a back fence at the rear part of the accommodating portion. Here, in a storage unit that stores a large amount of paper at one time, such as a cassette or a tray, there is not much operational trouble even if there is a back fence. However, when inserting paper directly into the paper feed port using a table, such as manual paper feeding, if the table has a back fence, it will take time and effort to insert the paper, and the back fence position must be set again to match the paper. The need also arises. For this reason, there is a problem that the merit of manual sheet feeding, which does not require the replacement of cassettes and the like, can be performed quickly, is impaired.

The present invention has been made in view of this point, and in a system in which cassette feeding and manual feeding are performed in the same feeding path, the double feeding is returned only when cassette feeding and manual feeding is performed. The purpose is to eliminate the need for a back fence for paper feeding.

[0007]

In order to achieve the above object, the present invention allows a cassette and a manual feed table to be selectively fed to a feeding path having a pair of feed roller, separate roller and pickup roller. In a sheet feeding device to be set, a shaft having the feed roller is connected to a drive side through an electromagnetic clutch that is turned on and off depending on whether or not a sheet is fed, and a shaft having the pickup roller is attached to the shaft of the feed roller. The separate roller is connected to the driving side through a torque limiter at all times, and the shaft of the feed roller is provided with a restricting means for returning the double-fed paper after the completion of feeding to stop the rotation. A solenoid that presses against the paper only when manually feeding paper, and a one-way clutch that locks the pickup roller at this time There is provided a sheet feeding apparatus.

Further, the regulating means is constructed to regulate the shaft of the feed roller by rotating the shaft of the feed roller by an amount necessary for returning the double-fed sheet when the electromagnetic clutch is turned off after the completion of the sheet feeding. desirable.

Further, it is desirable that the regulating device is constructed so that the shaft of the feed roller is locked immediately after the completion of the manual sheet feeding so that the double-fed sheet does not return.

[0010]

According to the above construction, when the cassette is set in the feeding path having one set of feed roller, separate roller and pickup roller, the electromagnetic clutch is turned on when feeding.
N, each roller rotates in the paper feeding direction, the paper in the cassette is fed, then the electromagnetic clutch is turned off, the feed roller and the separate roller are reversed by a predetermined amount, and the pickup roller is retracted by turning on the solenoid. The multi-fed paper is returned to the cassette. Also, when the manual feed table is set, the paper is fed in the same manner. In this case, the solenoid is turned off and the one-way clutch is engaged, so that the pickup roller is locked and pressed against the paper, so that the paper is fed to the manual feed table. Is prevented from returning.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. Referring to FIG. 1, the drive system of the friction separating / feeding apparatus will be described. The drive system has a gear 100 that rotates in a counterclockwise direction indicated by an arrow. The gear 100 is a gear 103 of a feed roller shaft 102 having a feed roller 101. Mesh with. An electromagnetic clutch 104 is provided between the gear 103 and the feed roller shaft 102.
By turning ON 04, the feed roller 101 is rotated in the clockwise direction indicated by the arrow, that is, in the sheet feeding direction A of the sheet. A shaft rotation restricting arm 106 is attached to the feed roller shaft 102 via a one-way clutch 105 that is integrally coupled during reverse rotation thereof.
The left and right rotational displacements are restricted by 08.

A gear 110 is mounted on the feed roller shaft 102 via a one-way clutch 109 which becomes free during reverse rotation of the feed roller shaft 102. The gear 110 is the idler gear 1.
11 via the gear 112 of the pickup roller shaft 113
Meshes with. A pickup roller 115 is mounted on the pickup roller shaft 113 via a one-way clutch 114 that is integrally coupled in the rotation direction, and when the electromagnetic clutch 104 is turned on, the feed roller 101 is attached.
At the same time, the pickup roller 115 also rotates in the sheet feeding direction A indicated by the arrow.

As shown in FIG. 2, the pickup roller 1
15 is held by a solenoid 200 via a spring 201. Then, when the solenoid 200 is turned on, the pickup roller 115 is lifted and separated from the sheet, and when the solenoid 200 is turned off, the pickup roller 115 is lowered and comes into elastic contact with the sheet.

On the other hand, the gear 117 meshes with the gear 117 of the torque limiter drive shaft 116 so as to rotate in the counterclockwise direction of the arrow, and the gear 118 of this drive shaft 116 meshes with the drive side gear 119 of the torque limiter 120. There is. Then, the separate roller 122 is fixed to the driven shaft 121 of the torque limiter 120, whereby the gear 10
At the time of 0 rotation, a constant torque is applied to the separate roller 122 in the direction opposite to the sheet feeding direction indicated by the broken arrow regardless of whether the electromagnetic clutch 104 is ON or OFF.

6 and 7, the paper feeding unit in which the cassette and the manual feed table are mounted will be described. 6
Reference numeral 00 denotes a sheet feeding unit. Inside the sheet feeding unit 600, the feed roller 101, the separate roller 122, and the pickup roller 115 are provided, and the cassette 610 is inserted immediately below this feeding path. Further, a manual feed table 620 is arranged immediately above the cassette of the paper feeding unit 600, and paper can be fed through the same feeding path.

The cassette 610 has a rising arm 611 inside.
It has a bottom plate 612 provided with, a back fence 613, and the like, and a large amount of sheets S are accumulated and stored. When the cassette 610 is attached to the sheet feeding unit 600 and is in the cassette sheet feeding mode, the raising arm 611 is rotated by the arm shaft 601 to raise the tip of the sheet S together with the bottom plate 612 as shown in FIG. The upper surface of the sheet S contacts the pickup roller 115. Then, when the upper surface of the sheet S and the pickup roller 115 reach the sheet feeding position, the sensor (not shown) stops the raising, and thereafter, the raising arm 611 is lowered every time the sheet S is fed and the position of the pickup roller 115 is lowered. Rotates so that the height of the upper surface of the paper S is kept constant.

The manual feed table 620 has an auxiliary plate 62 at its tip.
1 and is rotatably mounted by the shaft 602 of the supporting member 622 between the upper closed position in FIG. 6 and the substantially horizontal lower paper feeding position in FIG. When the manual feed table 620 is opened, the manual feed paper feed mode is switched by a changeover switch (not shown), the solenoid 200 is turned on and the pickup roller 115 is lifted, and the arm shaft 601 is rotated in the opposite direction to the above, and the cassette 610 is loaded. The raising arm 611, the bottom plate 612, and the sheet S are lowered. As a result, the auxiliary plate 621 of the manual feed table 620 is guided by the unit side plate rail and enters the sheet feeding position without colliding with the pickup roller 115 or the like. And the manual table 6
When the paper G is inserted by 20, the solenoid 200 is turned off by the paper detection sensor 202 in FIG. 2 to bring the pickup roller 115 into pressure contact with the paper G.

Next, the operation of this embodiment will be described. First, the case of cassette sheet feeding will be described. By rotating the manual feed table 620 upward and closing it, the cassette sheet feed mode is set. Then, the upper surface of the paper S inside the cassette 610 rises, and the solenoid 200 is turned off.
It comes into pressure contact with the pick-up roller 115 that descends, and both are set at the paper feed position so that paper can be fed.

Then, when the start button is turned on, the electromagnetic clutch 104 is turned on and the gear 100 is rotationally driven, and the feed roller shaft 102 or the like causes the feed roller 1 to rotate.
01 rotates in the feeding direction A, and at the same time, the gears 110, 11
1, 112, the pickup roller shaft 113, etc. also rotate the pickup roller 115 in the sheet feeding direction A, and the upper portion of the sheet S in the cassette 610 is sent out. At this time, when the paper S enters the feed roller 101 in a double-feed state of two or more sheets as shown in FIG. 2, the separate roller 122 applies torque to the opposite paper feed direction by the torque limiter 120. Due to the friction separating action of the roller 101 and the separate roller 122, the feeding of the second and subsequent sheets S is blocked, and thus the sheets S are separated one by one and stably fed. On the other hand, the multi-fed sheet S ′ that has been separated and left in this case is sandwiched and held in the nip portion between the feed roller 101 and the separate roller 122.

After the above paper feeding, the electromagnetic clutch 104 is turned off while the gear 100 is driven. Therefore, the feed roller shaft 102, the feed roller 101, and the pickup roller 115 are stopped and become free, but the separate roller drive shaft 116 is driven. Therefore, the separate roller 122 is unloaded and rotates in the opposite sheet feeding direction B, and accordingly, the feed roller 101 and the feed roller shaft 102 are rotated by the one-way clutch 109 to the gear 110.
It separates from and is rotated counterclockwise. At this time,
The solenoid 200 is turned on as shown in FIG. 3 and the pickup roller 115 is lifted, whereby the multi-feed sheet S ′ nipped between the feed roller 101 and the separate roller 122 is returned to the cassette 610 side, and the remaining sheet remains. Is prevented.

On the other hand, the arm 1 of the feed roller shaft 102
The paper 06 is rotated along with the paper feed and is in contact with one of the shaft rotation restricting members 108 as shown in FIG. When the feed roller shaft 102 rotates in the reverse direction, the one-way clutch 10
5, the arm 106 is integrally coupled and rotated as shown in FIG. 3, and comes into contact with the other shaft rotation restricting member 107 to restrict the rotation of the feed roller shaft 102. Therefore, a load is applied to the separate roller 122, and thus the torque limiter 120 operates to stop the rotation of the separate roller 122, and thus one cycle of cassette sheet feeding is completed.

Next, the case of manual sheet feeding will be described. In this case, when the manual feed table 620 is rotated downward and opened, the mode is switched to the manual feed mode, the auxiliary plate 621 enters the paper feed position as shown in FIG. The descending pick-up roller 115 comes into pressure contact with it, so that the sheet can be fed. Therefore,
When the start button is turned on, the electromagnetic clutch 104 turns off.
N, and the gear 100 is rotationally driven, the feed roller 101 and the pickup roller 115 are rotated as described above, and torque is applied to the separate roller 122. Then, in this manual feeding, in the case of a plurality of sheets G, all of them enter the feed roller 101 in a double feeding state, and are separated and fed one by one by the separate roller 122. After the paper feed, the electromagnetic clutch 104 is turned off, the feed roller shaft 102 and the arm 106 are similarly rotated by the rotation of the separate roller 122 in the opposite paper feed direction, and the rotation is restricted by the shaft rotation restricting member 107. and,
The rotation of the separate roller 122 also stops.

By the way, in this case, the pickup roller 115 is kept in pressure contact with the paper G as shown in FIG. For this reason, the return force F of the sheet G nipped between the separate roller 122 and the feed roller 101 by the reverse rotation causes the pickup roller 115 to rotate in the reverse direction. G is prevented from returning to the manual feed table 620. Therefore, in this case, as shown in FIG. 5, the sheet G bends upward and is pushed back from the feed roller 101 side, but is blocked by the pickup roller 115, and the remaining sheet when the sheet feeding is stopped is similarly prevented. It

The operation states of the electromagnetic clutch 104 and the solenoid 200 in the case of the above-mentioned cassette sheet feeding and manual sheet feeding are summarized as shown in Table 1 below.

[0025]

[Table 1]

Another embodiment of the present invention will be described with reference to FIG. In this embodiment, one shaft rotation regulating member 1
The solenoid 8 is movably supported and is turned on only in the manual feeding mode via the spring 801.
00. Therefore, in the manual paper feed mode, one of the shaft rotation restricting members 10 is controlled by the solenoid 800.
8 moves in the direction C of the other shaft rotation restricting member 107,
The arm 106 is brought into contact with the other shaft rotation restricting member 107 from the beginning. For this reason, the separate roller 12
Even if the sheet 2 tries to rotate in the direction opposite to the sheet feeding direction, the feed roller 101 is locked and does not rotate, and thus the sheet G is not returned.

[0027]

As described above, according to the present invention,
In a paper feeding device that performs cassette feeding and manual feeding in the same feeding path, the feed roller and the separate roller are reversed in the paper returning direction after feeding when cassette feeding,
Remaining paper can be reliably prevented. Further, during manual paper feeding, rotation of the feed roller and the separate roller in the paper returning direction is stopped, or the pickup roller is pressed against the paper, so that the paper is not returned. This eliminates the need for a back fence, prevents defective paper feeding, and allows manual copy feeding work to be performed efficiently.

[Brief description of drawings]

FIG. 1 is a perspective view showing a drive system of a sheet feeding device according to the present invention.

FIG. 2 is a side view showing a cassette sheet feeding state of the sheet feeding device according to the present invention.

FIG. 3 is a side view showing a state of the paper feeding device according to the present invention after feeding a cassette.

FIG. 4 is a side view showing a manual sheet feeding state of the sheet feeding device according to the present invention.

FIG. 5 is a side view showing a state after manual feeding of the paper feeding device according to the present invention.

FIG. 6 is a cross-sectional view showing a sheet feeding unit for cassette sheet feeding in the sheet feeding device according to the present invention.

FIG. 7 is a cross-sectional view showing a paper feeding unit for manual paper feeding in the paper feeding device according to the present invention.

FIG. 8 is a side view showing another embodiment of the paper feeding device according to the present invention.

[Explanation of symbols]

100 Drive side gear 101
Feed roller 102 Feed roller shaft 104
Electromagnetic clutch 114 One-way clutch 115
Pickup roller 120 Torque limiter 122
Separate roller 105 One-way clutch 106
Shaft rotation regulating arm 107 108 Shaft rotation regulating member 200
solenoid

Claims (3)

[Claims] 1. A paper feeding apparatus in which a cassette and a manual feed table are selectively set to be able to feed paper in a feeding path having a pair of feed roller, separate roller, and pickup roller, and a shaft having the feed roller is provided. It is connected to the drive side through an electromagnetic clutch that turns on and off according to the presence / absence of sheet feeding, the shaft having the pickup roller is connected to the shaft of the feed roller so as to be interlocked, and the separate roller is connected via a torque limiter. A solenoid that is always connected to the drive side, has a regulating means for stopping the rotation of the feed roller shaft by returning the multi-fed paper after the completion of feeding, and presses the pickup roller against the paper only when the paper is manually fed. A paper feeding device, characterized in that a one-way clutch for locking the pickup roller is provided. 2. The regulating means is configured to regulate the shaft of the feed roller by rotating the shaft of the feed roller by an amount necessary for returning the double-fed sheet when the electromagnetic clutch is turned off after the completion of sheet feeding. The sheet feeder according to claim 1, wherein the sheet feeder is a sheet feeder. 3. The feeding device according to claim 1, wherein the regulating device is configured to lock the shaft of the feed roller immediately after the completion of the manual paper feeding so that the double-feeding paper does not return. Paper equipment.