JPS6143256B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an automatic paper feeder for transporting and feeding paper sheets such as facsimile manuscripts and copying machine manuscripts one by one. In particular, the present invention relates to an automatic paper feeder that intermittently transports and feeds paper sheets at appropriate intervals.

[Conventional technology]

Between a feed roller that rotates continuously in one direction and a separation belt that contacts this feed roller and rotates in the opposite direction, the stacked sheets are reeled in from the direction of rotation of the feed roller. 2. Description of the Related Art An automatic sheet feeding device is known that sequentially transports and feeds sheets starting from the lowest or highest sheet.

In such a device, it is necessary to feed each transferred sheet with a sufficiently wide interval so that each sheet is completely separated as a single sheet to prevent malfunction in the subsequent process. Conventionally, as a method to maintain the distance between the sheets of paper being transferred, a second feed roller is provided immediately after the above-mentioned feed roller that continuously rotates in the same direction as this feed roller at a slightly faster speed, and this second feed roller is A method is known in which a pinch roller is provided in contact with the roller and the paper sheets are separated by a difference in rotational speed between the two feed rollers. In other words, when the trailing edge of the sheet being conveyed passes the first feed roller, the sheet is conveyed at the fast feed speed of the second feed roller, and the next sheet is newly conveyed by the first feed roller. The paper sheet is transported at the slow feed speed of this first feed roller.

Therefore, by the time the leading edge of the sheet newly transferred by the first feed roller reaches the second feed roller, the trailing edge of the sheet being transferred by the second feed roller is The sheets are transported faster by the speed difference between the two feed rollers, and the gap between the two sheets becomes wider. In order to obtain a sufficiently wide gap between sheets using this method, either increase the speed difference between the first and second feed rollers, or increase the distance between the first and second feed rollers. It is necessary to use a wide range of options or a combination of both.

[Problem that the invention seeks to solve]

However, if the speed difference between the first feed roller and the second feed roller is increased, large slippage will occur between the feed roller and the paper sheet, which has the disadvantage of accelerating the aging of the feed roller. I can't. Therefore, the distance between the first feed roller and the second feed roller must be increased to some extent, and the automatic paper feeding device becomes large, which has the disadvantage that it cannot be installed in a small-sized device. Furthermore, it has the disadvantage that it is not possible to transport short sheets of paper that are shorter than the distance between the two feed rollers.

The present invention aims to improve the above-mentioned drawbacks, and uses signals from a sensor that detects the transport status of paper sheets on the paper loading plate to control the rotation and stop of the feed roller, thereby ensuring appropriate spacing between each sheet to be transported. This system focuses on feeding, and the distance between the first and second feed rollers can be made very small, making it possible to transfer short sheets of paper and also making it possible to connect to small devices. The purpose is to provide a sufficiently small automatic paper feeder.

[Means for solving problems]

The present invention provides a method for transporting the stacked paper sheets one by one between a first feed roller that transports the stacked paper sheets one by one, and a first feed roller that is disposed adjacent to the outer peripheral surface of the first feed roller. a belt that rotates in a direction opposite to the first feed roller so as to separate the sheets one by one; a driving means that rotationally drives the belt and the first feed roller; The second feed roller is arranged a little apart from the feed roller in the transport direction, and the second feed roller is configured to sandwich a sheet of paper between the second feed roller and the second feed roller. In an automatic paper feeder equipped with a pinch roller, the driven roller contacts the endmost (lowest or highest) sheet of the stacked sheets and rotates as the sheet moves; It is characterized by comprising a sensor that detects the rotation of the driven roller, and a control means that controls the driving means based on an output signal of this sensor.

The control means rotates the drive means to feed one sheet of paper, and after a short period of time has passed since the driven roller stopped rotating, the control means rotates the driven roller and starts rotating again with the next sheet. It is preferable to include means for stopping the drive means and for giving rotation to the drive means again after a certain period of time has elapsed after stopping the drive means.

〔Example〕

The present invention will be explained based on the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention. This figure is a cross-sectional structural diagram, and the dash-dotted line in the figure shows a state in which the rotating shafts are connected. Dotted lines indicate the flow of control signals in the electrical system. The x mark represents the center of the rotation axis.

Paper sheets 2 are stacked on a paper mounting plate 1 having a flat surface. A press roller 3 is rotatably provided on the uppermost surface of the sheet 2 with its outer periphery in contact with the press roller 3. The presser roller 3 is rotatably connected via an arm 5 to a shaft 4 attached to a side plate (not shown), and is configured to press the sheet 2 downward with its own weight. Further, a driven roller 6 is rotatably attached to the lower surface of the sheet 2 with its outer periphery in contact with the lower surface. This driven roller 6 is mechanically connected to a sensor 7. This sensor 7 is the controller 2
2, and this control section 22 is connected to a switch 23.

Further, near the end surface of the paper placement plate 1, a first feed roller 8 (hereinafter referred to as "feed roller 8") is provided with an electric motor 9 serving as a driving means for the feed roller 8.
is mechanically connected to the A pulley 10 is directly connected to this feed roller 8, and a pulley 12 is mechanically connected to this pulley 10 via a belt 11. A separation roller 13 is connected to this pulley 12 . A guide roller 15 is mechanically connected to the separation roller 13 via a separation belt 14. This separation belt 1
4 is provided in contact with the outer periphery of the feed roller 8. The above feed roller 8 and separation roller 13
Guide plates 16 and 17 are provided facing each other near the. A second feed roller 19 (hereinafter referred to as "main feed roller 19") mechanically connected to an electric motor 18 is provided near the end surfaces of the guide plates 16 and 17.
A pinch roller 20 is rotatably provided on the outer periphery of the roller 20 in contact with the outer periphery. A guide plate 21 is provided near the contact point between the main feed roller 19 and the pinch roller 20.

In such a configuration, electric motors 9 and 18
starts, the feed roller 8 is rotated in the direction of arrow a in the figure, and the main feed roller 19 is rotated in the direction of arrow a'' in the figure.At this time, the pulley 1
0 also rotates integrally with the feed roller 8, and the belt 11
The pulley 12 is rotated via. This pulley 1
2 rotates the separation roller 13 integrally in the direction of arrow a' in the figure. As the separation roller 13 rotates, the separation belt 14 rotates in the direction of arrow b in the figure.

Here, the frictional force on the surface of the feed roller 8 is sufficiently larger than the frictional force on the outer circumferential surface of the separation belt 14, and the lowest sheet 2' of the sheets 2 stacked on the paper stacking plate 1 is moved by the feed roller 8. As 8 rotates, it is transferred in the direction of arrow c in the figure. On the other hand, the second sheet 2'' comes to rest at a point where the frictional force generated between it and the outer peripheral surface of the separation belt 14 and the frictional force generated between the lowest sheet 2' are balanced.At this time, The driven roller 6 rotates following the lowest sheet of paper 2', and a signal is detected by the sensor 7. This sheet of paper 2' is transported by the feed roller 8 and the main feed roller 19, and its trailing edge is rotated by the driven roller 6. After passing the roller 6, the driven roller 6 comes into contact with the second sheet 2'' from the bottom and stops rotating, so that the sensor 7 no longer detects the rotation.

Next, after a short time t ₁ has passed after the rotation of the driven roller 6 is no longer detected, the leading edge of the second sheet 2'' from the bottom reaches the contact point between the separation belt 14 and the feed roller 8. When the paper sheet 2'' reaches the destination, the conveyance of the sheet 2'' is started, the driven roller 6 also rotates, and the sensor 7
Rotation is detected again. This rotation signal is guided to the control section 22, and the electric motor 9 is controlled by the control section 22 so as to automatically stop after the minute time _t2 has elapsed.

That is, at this time, the trailing edge of the lowest paper sheet 2' that has been previously transported is also at the contact point between the separation belt 14 and the feed roller 8, but this trailing edge completely contacts this contact point. After the short time t ₂ necessary for passing has elapsed, the control unit 22 opens the switch 23 to automatically stop the electric motor 9.

When the electric motor 9 stops, the feed roller 8 stops,
The transport of the second sheet 2'' from the bottom is stopped. On the other hand, the transport of the sheet 2', which was initially at the bottom, is continued by the rotation of the main feed roller 19, and the gap between the two sheets gradually widens. After the elapse of a certain time T such that this interval does not cause malfunction in the next process, the switch 23 is closed by the control unit 22, the electric motor 9 is automatically rotated again, and the transfer of the subsequent sheet is started. Ru.

Here, in order to stop the electric motor 9 after a minute time t ₂ has elapsed since the signal from the sensor 7, for example, a delay circuit is provided in the control section 22 and the minute time t ₂ has passed since the signal from the sensor 7.
The switch 23 may be configured to be opened later.
Further, in order to rotate the electric motor 9 again after stopping it for a certain period of time T, for example, a delay circuit may be provided in the control section 22 and the switch 23 may be closed again after the elapse of the certain period of time T. As this delay circuit, a circuit using a flip-flop is known.

Each of the above operations will be explained using FIGS. 2 to 6. FIGS. 2 to 6 are operation transition diagrams of the above operations.

In FIG. 2, the paper sheets 2 stacked on the paper stacking plate 1 are moved by starting the electric motors 9 and 18.
Feed roller 8, separation belt 14, main feed roller 1
When the rotation of sheet 9 is started, sheets 2' of the lowest position are sequentially transferred in the direction of arrow c. At this time, the driven roller 6 follows the paper sheet 2' and rotates in the direction of arrow e in the figure, and the sensor 7 detects the rotation.

In FIG. 3, when the trailing edge of the sheet 2' passes the driven roller 6, the driven roller 6 contacts the bottom surface of the second sheet 2'' from the bottom.At this time, the sheet 2'' stops. Therefore, the driven roller 6 stops,
Sensor 7 does not detect rotation.

In FIG. 4, after a short time _t1 has elapsed after the driven roller 6 has stopped, the trailing edge of the sheet 2' passes through the contact point between the feed roller 8 and the separation belt 14, and the sheet 2'' The transport is started and the paper sheet 2'' is moved by the arrow c.
is transported in the direction of At this time, the driven roller 6
The paper sheet 2'' rotates in the direction of arrow e, and the sensor 7 detects the rotation again.

In FIG. 5, after the short time _t2 required for the trailing edge of the sheet 2' to completely pass through the contact point between the feed roller 8 and the separation belt 14, the electric motor 9 automatically stops. By stopping the electric motor 9, the feed roller 8 is stopped, and the transport of the sheet 2'' is stopped.

In FIG. 6, the distance between the trailing edge of the sheet 2' being transported by the main feed roller 19 and the leading edge of the sheet 2'' whose transport is stopped is such that it does not cause malfunction in the next process. After the predetermined time T has elapsed, the electric motor 9 is automatically started again, the feed roller 8 and the separation belt 14 are rotated, and the transfer of the sheet 2'' is automatically started. Thereafter, this operation is repeated until the interval between the sheets to be transferred is set so that they can be completely separated as one sheet, and the sheets are transferred without causing any malfunction in the next process.

FIG. 7 is an operation time chart. A shows the drive signal waveform of the electric motor 9, B shows the drive signal waveform of the electric motor 18, and C shows the output signal waveform of the sensor 7. The status column shows the corresponding operating time in FIGS. 2 to 6.

That is, in FIG. 2, when the lowest sheet is transferred by the feed roller 8 and the trailing edge of the sheet a' passes the driven roller 6, the output C of the sensor 7 is turned off. A short time after the output of sensor 7 is turned off
After _t1 , the feed roller 8 starts transporting the second sheet a'', so the driven roller 6 rotates and the output of the sensor 7 turns on.The output of the sensor 7 turns on. When a short time t ₂ has elapsed since then, the control section 22 opens the switch 23 to stop the electric motor 9 that drives the feed roller 8. When the electric motor 9 is stopped and a certain period of time T has elapsed, the electric motor 9 is turned on again. Rotate and restart the transfer of the second sheet a''.

FIG. 8 is a block diagram of a second embodiment of the present invention.
In the first embodiment, a single electric motor 9 is used as a drive means for rotating the feed roller 8 and the separation belt 14, but a motor common to the main feed roller 19 can also be used as the drive means. That is, in this second embodiment, a pulley 25 is fixed to the output shaft of the electric motor 18 that drives the main feed roller 19, a pulley 27 is fixed to the rotating shaft of the feed roller 8 via an electromagnetic clutch 26, A belt 28 is provided to connect the pulleys 25 and 27, and the rotating force of the electric motor 18 is transmitted to the feed roller 8, separation roller 13, and separation belt 14. Here, the electromagnetic clutch 26
The control section 22 operated by the signal from the sensor 7 transmits and cuts off the rotational force of the electric motor 18 to the roller 8, rotates the feed roller 8 and the separation belt 14,
make it stop. By controlling the electromagnetic clutch 26 in this manner, the present invention can be implemented.

FIG. 9 is a configuration diagram of a third embodiment of the present invention. In this third embodiment, the vertical positional relationship between the feed roller 8, separation roller 13, and separation belt 14 of the first embodiment is changed so that the feed roller 8 is placed on the upper surface of the paper sheet 2, and the separation belt 14 is placed on the top surface of the paper sheet 2. This is an example in which the present invention is implemented in an automatic paper feeder that sequentially transports and feeds paper sheets 2 starting from the uppermost sheet 2 ^{- 3} by bringing the sheet into contact with the lower surface of the sheet 2 .

Here, the driven roller 6 is rotatably connected via an arm 30 to a shaft 29 attached to a side plate (not shown), and by pressing the uppermost paper sheet 2 ^{- 3} with its own weight, It rotates and stops following the transfer of paper sheets ^2-3 . Hereinafter, the present invention can be implemented by detecting the operation of the driven roller 6 with the sensor 7 and rotating and stopping the electric motor 9 with the control section 22 and switch 23.

〔Effect of the invention〕

According to the present invention, the feed roller is automatically rotated and stopped in response to a signal from a sensor that detects the state of the paper sheets to be transported, and the interval between the sheets to be transported is separated into individual sheets. The interval can be set as required. Furthermore, since the paper can be separated and transported one by one, it is possible to feed the paper without malfunction in the next process. Furthermore, since the distance between the two feed rollers can be made very small, it is possible to automatically feed short sheets that could not be transferred using conventional automatic sheet feeding devices. Furthermore, the device itself can be made extremely compact, and has the advantage of being able to be installed in even small devices.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing a first embodiment of the present invention. This figure is a cross-sectional structural diagram, and the dash-dotted line in the figure shows a state in which the rotating shafts are connected. The x mark represents the center of the rotation axis. 2 to 6 are operation transition diagrams of the embodiment of FIG. 1. FIG. 7 is an operation time chart of the above embodiment. A, B, and C are signal currents at points with corresponding symbols shown in FIG. FIG. 8 is a configuration diagram showing a second embodiment of the present invention. FIG. 9 is a configuration diagram showing a third embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Paper placement plate, 2... Paper sheet, 6... Driven roller, 7... Sensor, 8... Feed roller, 9... Electric motor, 13... Separation roller, 14... Separation belt, 18... ...Electric motor, 19...Main feed roller, 2
0...Pinch roller, 22...Control unit, 23...
Switch, 26... Electromagnetic clutch, 29... Shaft,
30...Arm.

Claims (1)

[Claims] 1. Between a first feed roller 8 that transports stacked paper sheets one by one, and a first feed roller that is arranged adjacent to the outer peripheral surface of this first feed roller. a belt 14 that rotates in the opposite direction to the first feed roller so as to separate the stacked paper sheets one by one; a drive means 9 that rotationally drives this belt and the first feed roller; A second feed roller 19 is arranged at a distance from the belt and the first feed roller in the transport direction, and this second feed roller is configured to sandwich a sheet of paper between the second feed roller 19 and the second feed roller. In an automatic paper feeder equipped with a pinch roller 20 interlocking with a second feed roller, a driven roller 6 contacts the endmost sheet of the stacked sheets and rotates as the sheet moves. An automatic paper feeder comprising: a sensor 7 for detecting the rotation of the driven roller; and control means 22 and 23 for controlling the driving means based on an output signal from the sensor. 2 The control means rotates the drive means to feed one sheet of paper, and after a short time _t1 has elapsed since the driven roller stopped rotating, the control means rotates the driven roller and then starts rotating again with the next sheet. The automatic paper feeder according to claim 1, further comprising means for stopping the driving means after a time _t2 , and rotating the driving means again after a predetermined time T has elapsed after stopping the driving means. .