JPH0213529A - Paper separating mechanism for automatic paper feeder - Google Patents

Abstract

PURPOSE:To feed a paper stably without requiring maintenance even after a large quantity of papers is fed over a long term by providing a turning motion means for moving the friction surface facing with a roller in the counter paper feed direction. CONSTITUTION:A paper 2 energized in the paper feed direction through the frictional force of a roller 4 is subjected to blocking force by a separation pad 5 and passed sheet by sheet. Upon droppage of separation capacity of the separation pad 5, a knob 16 is turned slightly. Since rotation of a supporting shaft 10 causes torsion of a coil spring 14 at the free end 20 side to enlarge the inner diameter of the coil spring 14 so as to weaken gripping force of the supporting shaft 10, an upper support roller 7 rotates to feed the belt type separation pad 5. Consequently, the friction surface 6a facing with the roller 4 is renewed and the separation capacity of the separation pad is recovered.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to an automatic paper feeding device attached to an information input/output device such as a printer or an image reader. The present invention relates to an improvement in an automatic paper feeder equipped with a paper separation mechanism configured to pass a paper between a pressed separation pad and separate the paper into individual sheets.

(Prior art) As shown in FIG. 5, a paper feed roller that comes into contact with the upper or lower end surface of the paper sheets 2 stacked on the paper tray 1 is rotated to feed out the paper sheets. There is a known automatic paper feeding device that separates sheets by passing between the paper feeding roller and other rollers 4 that rotate in the paper feeding direction and a separation pad 5 that is pressed against the circumferential surface of the roller by a spring 3. It is.

Separation of the paper 2 between the roller 4 and the separation pad 5 is achieved by the frictional force from the roller 4 trying to send out the paper, the frictional force from the separation pad 5 trying to prevent the paper from passing, and the rigidity of the paper. It is based on a balance between the two, and if this balance is disrupted, double feeding or paper feeding errors will occur.

(Problem to be Solved by the Invention) The roller 4 and separation pad 5 are made of rubber so that sufficient frictional force can be transmitted to the paper, and the paper does not reach between them. Sometimes, the circumferential surface of the roller 4 and the separation pad 5 rub directly against each other. In this case, the entire circumferential surface of the roller 4 comes into contact with the paper 2 and the separation pad 5, but since the contact point on the separation pad 5 side is always the same, wear of the pad 5 and adhesion of paper dust occur at this one point. The friction load applied to the paper from the pad 5 gradually decreases.
After a relatively short period of use, the paper separation ability decreases, making double feeding more likely to occur. Therefore, in an apparatus with a high operating rate, maintenance work such as cleaning or replacing the separation pad 5 is required frequently.

Therefore, an object of the present invention is to provide an automatic paper feeder that can stably feed paper without maintenance even after feeding a large amount of paper for a long period of time.

(Means for Solving the Problem) In the present invention, the separation pad 5 is made of a member having an endless friction surface 6, such as an endless bell 1-, and is opposed to the roller 4. The support member 9 of the member having the endless friction surface 6 is provided with a circumferential moving means 7 for moving the surface 6a of the friction surface facing the roller 4 in the counter-sheet feeding direction, and a rotating means 7 for preventing movement in the sheet feeding direction. A locking means 14 is provided.

The orbiting means may be equipped with a manually operated knob 16 or a lever, but the orbiting means is connected to a swinging member 27 for opening the paper path 25 of the automatic paper feeder via a one-way clutch 34. A structure in which transportation means are connected is more effective.

(Function) In the above configuration, the paper 2 urged in the paper feeding direction by the frictional force of the roller 4 tries to push the separation pad 5 in the paper feeding direction, but if it moves in this direction, the locking means 14 Since the paper is blocked by the separation pad 5, a blocking force is applied to the paper that is about to pass from the separation pad 5, and the paper 2 is separated one by one and passes.

When the separation ability of the separation pad 5 decreases, the rotation movement means 7 is operated to move the separation pad 5 in the opposite direction of paper feeding,
A new surface of the separation pad 5 can be opposed to the roller 4, thereby restoring the separation ability.

Further, when the separation ability of the separation pad 5 decreases, a double feed occurs, and when recovering from this, the paper path 25 is opened, so the member 27 that swings when the paper path 25 is opened.
By linking the orbiting means 7 via the one-way clutch 34, the friction surface 6 of the separation pad 5 can be automatically updated upon recovery from double feed.

Since the separation pad 5 has an endless friction surface 6, by updating the friction surface 6a facing the roller 4 from time to time, the wear of the friction surface 6 and the adhesion of paper powder become uniform, and the separation pad Since the life of roller 5 can be made to be about the same as that of roller 4, this is convenient for maintenance work.

(Embodiment) FIGS. 1 and 2 are views showing a first embodiment of the present invention, in which FIG. 1 is a perspective view showing a separation pad structure, and FIG. 2 is a side view of the entire device. The illustrated apparatus has a structure in which sheets 2 stacked on a sheet tray 1 are sequentially fed from the bottom, and a separation pad 5 is opposed to the sheet feeding roller 4 itself. The separation pad 5 is a rubber endless bell 1~
It is wound between upper and lower support rollers 7 and 8. The support roller 7.8 is pivotally supported by a swing frame 9, which is pivotally supported on an upper frame 11 by a support shaft 10 that is integral with the upper support roller 7. A radial groove 1 is provided in the portion of the swing frame 9 that passes through the support shaft 10.
A coil spring 14 is interposed between the inner periphery of the boss 13 and the outer periphery of the support shaft 10. The coil spring 14 is cloth-wound and has an inner diameter that fits snugly around the outer periphery of the support shaft 10, and a cotton end 15 that stands up in the radial direction at the outer end is inserted into the groove 12 of the boss. . A knob 16 is fixed to the tip of the support shaft 10 that passes through the swing frame 9 and the upper frame 11. An arm 17 extending upward is integrally formed on the swing frame 9, and the tip of the arm 17 and the upper frame 1
A tension spring 18 is stretched between the separation pad 5 and the separation pad 5.
The friction surface 6 of the roller 4 is pressed against the outer peripheral surface of the roller 4. Reference numeral 19 denotes a pair of rollers that nip the paper after it has passed through the abutting portion between the roller 4 and the separation pad 5 and send it to a printing section of a printer or a reading section of an image reader.

The friction surface 6a of the separation pad 5 facing the paper feed roller 4 has a surface 6a that faces the paper feed roller 4 in the paper feeding direction, that is, the separation pad 5.
A frictional force is applied that tries to rotate it clockwise. This frictional force tries to rotate the support roller 7 and therefore the support shaft 10 clockwise in the drawing, but the coil spring 14 fitted into the support shaft 10 causes its free end 20 side to turn to the right due to friction with the support shaft 10. The support shaft 1 is twisted around the support shaft 10 and fastened to the support shaft 10.
Prevents rotation of 0. Therefore, the separation pad 5 does not rotate, and its friction surface 6 remains stationary and applies a frictional force to the paper 2 in a direction that prevents its passage.

On the other hand, when a decrease in the separation ability of the separation pad 5 is recognized, the knob 16 is slightly rotated counterclockwise in the figure.

At this time, the counterclockwise rotation of the support shaft 10 is caused by the coil spring 1
4, the free end 20 side of the coil spring 14 is twisted in the direction in which the inner diameter is expanded and the grip on the support shaft 10 is weakened, so the upper support roller 7 rotates and separates into a belt-like shape. Rotate pad 5. Therefore, the friction surface 6a facing the roller 4 is renewed, and the separation ability of the separation pad is restored.

3 and 4 show a second embodiment of the present invention, in which the friction surface of the separation pad 5 is updated every time the paper path is opened. In the figure, 23
is a pin that pivotally connects the upper frame 11 and the lower frame 24, and the upper frame 11 can rotate upward around this pin. The support shaft 10 of the separation pad and the upper part 19a of the roller pair 19 are connected to the upper frame 1.
1, the lower one 19b and the paper feed roller 4 are pivotally supported on the lower frame 24, and the paper tray 1 is pivoted on the lower frame 24.
is installed on. Therefore, when the upper frame 11 is rotated upward, the rollers 19a and 19b of the roller pair 19 are separated, and the paper feed roller 4 and separation band 5 are also separated, and the paper path 25 is opened.

26 is a locking pin installed in the lower frame 24, 27 is a lever pivotally attached to the upper frame 11 at a fulcrum pin 28,
A recess 29 provided at the base end of this lever 27 and a locking pin 2
6 are engaged to fasten the upper frame 11 to the lower frame 24. A link 30 is pivotally attached to the intermediate portion of the lever 27, and the lower end of this link 30 and the tip of an operating arm 31 pivotally attached to the support shaft 10 are pivotally connected. The operating arm 31 is pivotally attached to the support shaft 10 using a structure similar to that of the swing frame 9 and the support shaft 10 described above. That is, 32 in FIG. 4 is a boss fixed to the operating arm 31, 33 is a groove in the radial direction of the boss 32, and 34 is 1ll.
It is a cloth-wound coil spring having a strand end 35 that fits into the outer periphery of the support shaft 10 and an inner diameter that fits around the outer periphery of the support shaft 10.

In this second embodiment, the knob 16 is not provided at the tip of the support shaft 10.

In the configuration of the second embodiment, when the separation ability of the separation pad 5 decreases and double feed occurs, the lever 27 is moved upward to recover from the double feed.
and open the upper frame 11. When the lever 27 is moved upward, the operating arm 31 connected to the link 30
rotates clockwise in the figure, but this rotation is in the direction of loosening the fitting between the coil spring 34 at the base end of the operating arm and the support shaft 10, and also moves the coil spring 14 on the swing frame side toward the support shaft 1.
0, the coil spring 34 at the base end of the operating arm and the support shaft 10 slip, and the support shaft 10 and hence the support roller 7 do not rotate.

Next, when the upper frame 11 is closed and the lever 27 is pushed downward to fasten the upper frame 11 to the lower frame 1.24, the link 3o rotates the operating arm 31 counterclockwise, and this rotation is , the coil spring 34 at the base end of the operating arm is fastened to the support shaft, and the coil spring 14 at the swing frame side is fastened to the support shaft.
Since the direction is to loosen the support shaft 10, the support shaft 10 rotates and the support roller 7 is rotated counterclockwise in the figure. This rotation updates the friction surface 6a of the separation pad 5 facing the roller 4. That is, in this second embodiment, the operator does not need to pay particular attention to updating the friction surface of the separation pad, and the updating operation is performed every time the paper path 25 is opened due to the occurrence of paper feeding trouble.

(Effects of the Invention) According to the structure of the invention described above, the surface of the separation pad that rubs against the roller and paper is constantly updated, and the frictional load and separation capacity of the separation pad are always kept constant, resulting in stable operation. Paper can be fed easily, and the number of maintenance operations such as cleaning and replacing separation bands can be greatly reduced.

[Brief explanation of the drawing]

1 and 2 are views showing a first embodiment of the present invention, in which FIG. 1 is a perspective view showing a separation pad structure, and FIG. 2 is a side view of the entire device. 3 and 4 show a second embodiment of the present invention, FIG. 3 being a side view of the entire device, and FIG. 4 being a perspective view showing the one-way clutch section. FIG. 5 is an overall side view of a conventional automatic paper feeder. In the figure, 2: Paper 4: Roller 5: Separation pad 6: Friction surface

Claims (2)

[Claims] (1) Automatic paper feed that separates and feeds paper (2) into individual sheets by passing the paper (2) between a roller (4) that rotates in the paper feeding direction and a separation pad (5) that comes into contact with the roller (4) In the paper separation mechanism of the apparatus, the separation pad (5) has an endless friction surface (6), and a circular movement means moves the surface (6a) of the friction surface facing the roller (4) in the opposite paper feeding direction. (7
) and a locking means (14) for preventing the surface (6a) from moving in the paper feeding direction. (2) The circulating means (7) is connected via a one-way clutch (34) to a swinging member (27) for opening a paper path (25) of an automatic paper feeder. The paper separation mechanism according to item 1.