JPH0555313B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to an improvement in an automatic paper feeder for a printer, and more particularly to an automatic paper feeder in which a single motor drives a paper feed roller and a paper discharge roller.

[Prior art]

Conventionally, in an automatic paper feeder (cut sheet feeder) installed in a printer, the paper feeding operation is performed by driving the paper feed roller by the motor on the automatic paper feeder side, and the paper ejection operation is performed by driving the paper feed roller of the printer. This was done by a paper ejection roller that was driven by the rotation of the paper. However, in this case, the paper feed roller and the paper ejection roller are constantly driven, and if the paper feed roller and the paper ejection roller are not synchronized, the paper may sag or bend.
For this reason, it is necessary to synchronize the paper feed roller and the paper discharge roller, which complicates the configuration of the device and increases costs. Therefore, the present applicant has proposed an automatic paper feeding device in which the paper ejection roller is released from its operating position when paper is fed by switching the rotation direction of the drive motor that drives the paper feeding roller between forward and reverse directions. .

〔the purpose〕

The present invention is designed to enable rotational force to be transmitted to the paper feed roller during paper feeding and to prevent reverse rotational force from being transmitted to the paper feed roller during such a drive motor switching operation. This paper aims to provide an automatic paper feeding device.

〔composition〕

Therefore, the automatic paper feeder of the present invention includes a transmission path that transmits the rotational force of the drive motor in the first direction to another transport member via the central axis of the paper feed rotation member, and a transmission path that transmits the rotational force of the drive motor in the first direction to the other transport member. The first drive motor is connected to the center shaft.
a one-way clutch that allows rotation of the paper feeding rotation member in the paper feeding direction in response to a rotational force in a second direction different from the rotational force in the first direction; , a locking means that operates to prohibit rotation of the paper feeding rotation member, and a spring clutch as the one-way clutch and a spring clutch as the locking means are disposed coaxially and overlappingly, and One end of the spring clutch of the locking means is fixed to the device frame.

〔Example〕

Embodiments of the present invention will be described in detail below based on the drawings.

1 and 2 are a side sectional view and a plan view of a main part of an automatic paper feeder according to an embodiment of the present invention. As shown in the figure, the automatic paper feeder 2 is removably installed in the printer 4. The automatic paper feeder 2 includes a drive motor 6 that can rotate in two directions, forward and reverse, a paper feed roller 18 as a paper feed rotation member, and a rotational force transmission path (described later) from the motor 6 to the paper feed roller 18. A paper ejection roller 10 is provided as a conveyance member through which driving rotational force for paper ejection is received. The motor 6
is fixed to the automatic paper feeder 2, the motor shaft 12 of the motor 6 is rotatably installed through the side plate 14 (FIG. 2) of the automatic paper feeder 2, and a motor pulley 16 is attached to the end.
is fixed. Further, a paper feed roller shaft (center shaft) 20 having a pair of paper feed rollers 18 is provided on the side plates 14, 14.
is rotatably installed. The paper feed roller shaft 20
Large-diameter first paper feed pulleys 22, 22 are fixed to the outside of the side plates 14, 14, and further, small-diameter second paper feed pulleys 24, 24 are fixed to the outer side. The side plates 14, 14 of the paper feed roller shaft 20 and the first paper feed pulley 2
2 and 22, relay plates 26 and 26 are rotatably provided on the paper feed roller shaft 20. The relay plate 26,
26 and the side plates 14, 14 further include a paper ejection roller shaft 2.
8 is rotatably provided. The paper ejection roller shaft 28
There is a paper ejection pulley 30 on the outside of the relay plates 26, 26,
30 is fixedly installed. Further, a paper ejection roller 32 is fixed to the paper ejection roller shaft 28 . A first belt 34 is wound between the motor pulley 16 and the first paper feed pulley 22, and a second belt 34 is wound between the second paper feed pulley 24 and the paper ejection pulley 30 as the above-mentioned conveyance path.
6 is wound. A spring 38 is compressed between the paper ejection pulley 30 and the relay plate 26.

A first spring clutch 60 as a locking means and a second spring clutch 62 as a one-way clutch are provided between the paper feed roller 18 and the paper feed roller shaft 20.

3 is a cross-sectional view of the paper feed roller 18, FIG. 4 is a perspective view of the paper feed roller 18, and FIG. 5 is a perspective view of the second spring clutch. A rubber portion 66 for contact is fixed, and the molded portion 64 is rotatable with respect to the paper feed roller shaft 20. A first spring clutch 60 having a diameter slightly smaller than the outer diameter of the molded part 64 is provided around the molded part 64. Since the diameter of the first spring clutch 60 is slightly shorter than the outer diameter of the molded part 64, the first spring clutch 60 is installed while pressing the molded part 64 inward in the radial direction. One end of the first spring clutch 60 is engaged with a portion 68 (FIG. 4) of the automatic feeder, and the other end is free.

A notch 70 is provided at the end of the mold part 64. Further, a second spring clutch 62 is provided around the paper feed roller shaft 20 (FIG. 5), and since the diameter of the second spring clutch 62 is also slightly shorter than the outer diameter of the paper feed roller shaft 20, the second spring clutch 62 is used for paper feeding. Roller shaft 2
While pressing the paper feed roller shaft 20 inward in the radial direction,
established in One end of the second spring clutch 62 is provided with a raised portion 72, and the other end is free, and the raised portion 72 is engaged with a notch 70 in the molded portion 64. (FIG. 3) The first spring clutch 60 allows the paper feed roller 18 to rotate only in one direction, as shown in FIG. In other words, when the paper feed roller 18 attempts to rotate (reversely) in the F direction (first direction), the first spring clutch 60 closes and the first spring clutch 60
Since one end of the paper feed roller 18 is engaged with and fixed to a part of the frame of the automatic paper feeder, the paper feed roller 18 cannot rotate and is locked. However, the rotation of the paper feed roller 18 in the E direction (second direction) is controlled by the first spring clutch 60.
Since the paper feed roller 18 can be loosened and freely rotated, the paper feed roller 18 can rotate freely without being restricted.

The second spring clutch 62 transmits rotation of the paper feed roller shaft 20 in only one direction to the paper feed roller 18. That is, the paper feed roller shaft 20 rotates normally (direction C =
(second direction), the second spring clutch 62 is closed and forward rotation of the paper feed roller shaft 20 is transmitted to the paper feed roller 18. However, when the paper feed roller shaft 20 is stopped, the paper feed roller 18 rotates forward (E direction = second direction).
direction), the second spring clutch 62 will loosen and the paper feed roller shaft 20 will not rotate.
Further, when the paper feed roller shaft 20 is reversed in the D direction, the first spring clutch is closed, the second spring clutch is loosened, and the paper feed roller 18 does not rotate.

Further, in FIG. 1, 40 is a stack of paper, 42 is a paper press plate for pressing the paper stack 40 against the paper feed roller 18, 44 is a separation claw, 46 is a paper feed port, 48 is paper,
50 is a paper feed roller; 52 and 54 are first and second rollers;
The pinch roller 56 is a paper discharge port.

Next, the effect will be explained. Motor 6 is A in the diagram.
When the first belt 34 rotates in the direction, the first paper feed pulley 22 and the paper feed roller shaft 20 rotate in the forward direction, that is, in the E direction (FIG. 1), and the second spring clutch 62 is automatically tightened and the second Spring clutch 62
The rising part 72 and the notch 7 of the mold part 64
0, the mold portion 64 and the paper feed roller 18 also rotate in the normal direction, that is, in the E direction. At this time the first
The spring clutch 60 is loose and the paper feed roller 18 is not restrained by the first spring clutch 60.

When the paper feed roller 8 rotates in the direction C in the figure, the uppermost sheet of the paper bundle 40 comes off the separation claw 46, and the paper passes through the paper feed port 46 and is delivered to the printer 4 by the rotation of the paper feed roller 8. It is transferred to the contact point between the feed roller 50 and the second pinch roller 54. When the leading edge of the paper 48 comes into contact with the contact point between the paper feed roller 50 and the second pinch roller 54, the drive of the motor 6 is stopped and the paper feed roller 50 is driven by a drive source (not shown), and the paper 48 is moved between the first pinch roller 52 and the paper feed roller 52. The paper passes between the paper feed roller 50 and is transferred to the paper discharge port 56 while being printed by the printer 4.

At this time, the motor 6 is stopped, but the paper 48
The paper feed roller 18 is in contact with the rear of the paper 4.
As the feed of the paper 8 progresses, the paper feed roller 18 feeds the paper 4.
8 rotates in the E direction in the figure. At this time, the first
Since both the spring clutch 60 and the second spring clutch 62 are loosened, the paper feed roller shaft 20 does not rotate even if the paper feed roller 18 rotates. That is, the paper feed roller 18 rotates idly.

Next, when the trailing edge of the paper 48 reaches the point of contact between the paper feed roller 50 and the first pinch roller 52,
Driving of the paper feed roller 50 is stopped. At this time, the motor 6 begins to rotate in the reverse direction in the direction B in the figure. This rotation is transmitted to the paper ejection pulley 30 via the first belt 34, the first paper feed pulley 22, the second paper feed pulley 24, and the second belt 36, and the paper ejection roller 10 rotates in the H direction in the figure. . At this time, the paper discharge roller 10 comes into contact with the paper 48, and as the paper discharge roller 10 rotates in the direction H in the figure, the paper 48 is discharged from the printer 4.

While the paper 48 is being ejected, the paper feed roller shaft 20 also rotates in the opposite direction, that is, in the D direction. At this time, the first spring clutch 60 is closed, and the paper feed roller 18 becomes unable to rotate. At this time, the second spring clutch 62 is loosened, and only the paper feed roller shaft 20 rotates, and the paper feed roller 18 does not rotate. That is, the paper is not fed in the opposite direction by the paper feed roller 18.

Switching between forward and reverse rotation of the motor 6 and driving of the paper feed roller 50 are performed by a control section (not shown) that detects the position of the paper 48 with a sensor (not shown) and receives a signal from the sensor.

In this embodiment, the power from the motor is transmitted using a belt, but it goes without saying that gears or the like may also be used.

〔effect〕

As described above in detail and specifically, according to the present invention, there is provided a transmission path for transmitting the rotational force of the drive motor in the first direction to another conveyance member via the central axis of the paper feed rotation member; A one-way clutch is provided between the paper rotation member and the central shaft to permit rotation of the paper feed rotation member in the paper feed direction in response to a rotational force of the drive motor in a second direction different from the first direction. , a locking means that operates to inhibit rotation of the paper feed rotation member from rotation of the central shaft due to rotational force in the first direction, and a spring clutch as the one-way clutch and the locking means. The spring clutches of the locking means are arranged so as to coaxially overlap each other, and one end of the spring clutch of the locking means is fixed to the apparatus frame side. Therefore, when switching the drive motor, the paper feed rotation member When a rotational force is applied from the central axis in the second rotational direction, the one-way clutch operates to enable rotational force transmission during paper feeding, and also when the rotational force is applied from the central axis to the first rotational direction.
When a rotational force is applied in the direction of rotation of the sheet, the locking means is activated by the minute torque transmitted from the central shaft, which prevents the transmission of reverse rotational force during paper ejection, etc., and prevents sheets from being fed backwards at the paper feed location. is obtained, and since the arrangement of each spring clutch is coaxial,
The miniaturization of the device can be promoted.

[Brief explanation of the drawing]

1 and 2 are a side sectional view and a plan view of essential parts of an automatic paper feeding device according to an embodiment of the present invention, FIG. 3 is a sectional view of a paper feeding roller, and FIG. 4 is a sectional view of a paper feeding roller. FIG. 5 is an enlarged perspective view of the second spring clutch. In the figure, 2... automatic paper feeder, 4... printer, 6... motor, 10... paper ejection roller, 18
... Paper feed roller, 60 ... First spring clutch, 6
2...Second spring clutch, 70...Notch. It is.

Claims (1)

[Claims] 1. A transmission path for transmitting the rotational force in the first direction of the drive motor to another conveying member via the central axis of the paper feed rotation member, and a first transmission path of the drive motor between the paper feed rotation member and the center axis. a one-way clutch that allows rotation of the paper feeding rotation member in the paper feeding direction in response to a rotational force in a second direction different from the rotational force in the first direction; , a locking means that operates to prohibit rotation of the paper feeding rotation member, and a spring clutch as the one-way clutch and a spring clutch as the locking means are disposed coaxially and overlappingly, and An automatic paper feeding device characterized in that one end of a spring latch of a locking means is fixed to the device frame side.