JPH0322191Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to an automatic paper feeding device such as a facsimile machine that feeds stacked transmission documents one by one starting from the lowest layer of paper.

Structure of the conventional example and its problems As shown in FIGS.
a, 1b, and two reversing rollers 3 provided on the shaft 4
a, 3b are pressed against each other at both ends of the shaft 4, and the driving force of the drive shaft 2 is transferred to the reverse rotation rollers 3a, 3 via the transmission rollers 5, 6, 7, the coil spring 8, and the friction plate 9.
It was transmitted to b. This coil spring 8 and friction plate 9
constitutes a torque limiter that transmits the reversing force when the load torque value is less than a predetermined value, and does not transmit it otherwise. In this case, since the rotational force transmitted from the paper feed rollers 1a and 1b through the document becomes small, the reversing roller 3 rotates in the direction of the arrow C and feeds only the lowest layer paper.
However, when the number of incoming transmission documents 10 is one,
The rotational force transmitted from the paper feed rollers 1a and 1b through the document increases, and the reversing roller 3 is pulled by the paper feed rollers 1a and 1b rotating in the direction of the arrow B, and rotates in the direction of the arrow C.
It was rotating in the opposite direction. However, in the conventional paper feeding device, since the reverse force was transmitted at the end, the force added to the pressing force _F1 acts at the end where the transmission rollers 5, 6, and 7 are present, and the roller 1
The contact pressure between rollers a and 3a and the contact pressure between rollers 1b and 3b are different, resulting in the disadvantage that the transmitted document 10 is fed crookedly.

Conventionally, in order to correct this drawback, the pressing force F ₁ ,
I was adjusting _F2 , but this required highly accurate adjustment work and took a long time.

Purpose of the invention The present invention was made in view of the above-mentioned drawbacks, and it is possible to feed the transmitted document straight with a simple configuration.
Moreover, it is an object of the present invention to provide an automatic paper feeding device that does not require adjusting the relative pressing force between a plurality of paper feeding rollers and a reversing roller.

Structure of the invention The automatic paper feeder of the invention has a second paper feed roller that contacts two paper feed rollers provided on a first drive shaft with its own weight.
The reversing force is transmitted at an intermediate position between two reversing rollers provided on the axis of the rotor, and a torque limiter is incorporated into the transmission system.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments will be described based on the drawings.

FIG. 3 is a plan view of an automatic paper feeder showing an embodiment of the present invention, and FIG. 4 is a sectional view taken along line XX' in FIG. In FIG. 3, 11 is a drive shaft, and 12 is a gear fixed on the drive shaft 11. Arms 13a and 13b are provided rotatably with respect to the drive shaft 11 and immovably in the longitudinal direction of the shaft 11. This arm 13a, 13
A shaft 14 is similarly provided at the other end of b. Therefore, the drive shaft 11 and the shaft 14 are always kept apart from each other. 15a and 15b are stop members fixed to the shaft 14, and 16a and 16b are reversing rollers provided on the shaft 14 to be rotatable and movable in the longitudinal direction of the shaft. 17 is a friction plate provided on the shaft 14 so as to be movable only in the longitudinal direction of the shaft; 18 is a coil spring; 19
is a gear that meshes with the gear 12 and is provided on the shaft 14 so as to be movable only in the longitudinal direction of the shaft. Therefore, the coil spring 18 stops the rollers 16a, 16b via the gear 19 and the stop member 15a, 17 through friction.
15b.

Further, in FIG. 4, 20 is a paper feed roller that rotates in the direction of arrow D, 21 is a rotating shaft of the paper feed roller 20, and 22 is a document to be transmitted that enters in the direction of arrow H. Note that the arrow G indicates the rotation direction of the drive shaft 11 and the gear 12. Although not shown, there are the same number of paper feed rollers as the reversing rollers 16a and 16b. In FIG. 4, the same members as in FIG. 3 are designated by the same reference numerals.

The operation of the automatic paper feeder according to the present invention having the above configuration will be explained below. First, on the rotating shaft 14, only the reversing rollers 16a and 16b are rotatable with respect to the rotating shaft 14, and the reversing roller 1
Since both sides of the rollers 6a and 16b are in frictional contact with other members, the reversing rollers 16a and 16b rotate in the same direction as the rotating shaft 14 when the rotational force transmitted from the paper feed roller 20 is small, and vice versa. roller 2
When the rotational force transmitted from 0 is large, the rotating shaft 14
It becomes unrelated to the rotation of . That is, by adjusting the pressing force of the coil spring 18, when the sending document 22 is not interposed between the paper feed roller 20 and the reversing rollers 16a, 16b, or when the sending document 22 is
When only one sheet of 2 is present, the reversing roller 16
Since the rotational force transmitted from the paper feed roller 20 applied to the paper feed rollers 20 a and 16b increases, the rotational force applied to the reversing rollers 16 a and 16 b
is independent of the rotation of the rotating shaft 14, and rotates in the direction opposite to the arrow E as the paper feed roller 20 rotates, and vice versa.
When there are multiple documents to be sent between the
Since the rotational force transmitted from the bottom layer decreases, the reversing rollers 16a and 16b rotate in the direction of the arrow E in accordance with the rotation of the rotating shaft 14, and feed the transmission documents 22 other than the bottom layer paper in the direction opposite to the arrow H. . Therefore, in this embodiment as well, stacked transmission documents can be fed one by one starting from the lowest layer.

By the way, the shaded areas in FIG. 5 indicate the reversing rollers 16a, 16b and the paper feed roller 20 that satisfy the above functions.
The relationship between the contact pressure and the torque limit value of the reversing rollers 16a and 16b is shown. As is clear from the figure, for example, if the contact pressure is set to a constant J, the torque limiter setting value may be set within a certain range L. According to this embodiment, the rotating shaft 1
4 is swingable with respect to the drive shaft 11, the reversing rollers 16a and 16b are rotated by their own weight to the paper feed roller 20.
is in contact with. Therefore, the contact pressure is uniformly determined. In this case, if the pressing force of the coil spring is determined in advance so that the torque limit value can be set within a predetermined range, the automatic paper feeder can be assembled without any adjustment.

Further, according to this embodiment, the transmission of the reversing force is performed using a gear at an intermediate position between the reversing rollers 16a and 16b. When this reversal force is transmitted, the arrow line
A force component also acts in the _F3 direction, but since this force acts equally on the reverse rotation rollers 16a and 16b, the original document 22 to be sent will not be fed crooked.

Furthermore, according to this embodiment, since the torque-mittance means is provided coaxially with the reversing roller, the reversing roller can be differentially moved by one torque-mittling means, so that a plurality of documents to be sent can be bent in their approach. When this happens, the feeding direction of the second and subsequent documents to be transmitted can be corrected.

Effects of the Invention As described above, according to the automatic paper feeding device of the present invention, the relative pressing force between the plurality of paper feeding rollers and the reversing roller can be uniformly determined with a simple configuration.
In addition, stacked transmission originals can be fed one by one from the lowest layer paper without adjusting the pressing force and without causing paper feed bending.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of essential parts of a conventional automatic paper feeder, Fig. 2 is a side view of the same, Fig. 3 is a schematic plan view of an automatic paper feeder according to an embodiment of the present invention, and Fig. 4 is a schematic plan view of the same. 3 is a sectional view taken along the line X-X' in FIG. 3, and FIG. 5 is a correlation diagram between the contact pressure and the torque limit value. 11... Drive shaft, 12... Gear, 13a, 13
b... Arm, 14... Rotating shaft, 15a, 15b
...stop member, 16a, 16b...reverse roller,
17...Friction plate, 18...Coil spring, 19...
Gear, 20...paper feed roller, 22...transmission original.

Claims (1)

[Scope of utility model registration request] A pair of paper feed rollers 20 are fixedly attached to a first drive shaft 21, and a rotation shaft 14 is supported by holding means 13a, 13b so as to be rotatable. a pair of reversing rollers 16 that are swingably provided around the drive shaft 11 and abut against the pair of paper feed rollers 20 by their own weight; and a first gear 12 that is fixed to the second drive shaft 11. , a second gear 19 provided at the center of the rotating shaft 14 and meshing with the first gear 12; and the second gear 19.
and torque limit means 15, 17, and 18 for regulating the transmission of the driving force from the first gear 12 to the reversing roller 16. a driving force transmission means for transmitting the driving force to the reversing roller 16;
The rotary shaft 14 is swingably supported by the second drive shaft 11, and a component of the transmission force from the first gear 12 moves each of the reversing rollers 16 to each of the paper feed rollers 2.
An automatic paper feeder characterized in that it makes contact with zero with an even contact pressure.