JPH1095547A - Paper sheet feeding and separating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper sheet feeding and separating device capable of suppressing generation of jamming or mis-feed by controlling the nip quantity with excellent accuracy by a simple mechanism and a control method. SOLUTION: This paper sheet feeding and separating device is provided with an upper separation roller 5 and a lower separation roller 6 arranged opposite to the upper separation roller 5, and separates a plurality of paper sheets 7 entering between the upper separation roller 5 and the lower separation roller 6 and carries one by one. A support plate 9 is provided, the lower separation roller 6 is provided on the support plate 9, and a motor 1 which is a stepping motor of the type where a motor shaft is moved in the axial direction is connected to the support plate 9 through a motor shaft 2 and an L-shaped plate 4 because the support plate 9 is driven in the turning direction around a supporting point 10 on the support plate 9 which is away from the lower separation roller 6 by the prescribed distance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper separating device used for an electrophotographic copying machine, a printer, a facsimile machine, and the like.

[0002]

2. Description of the Related Art In such an apparatus, a sheet feeder having a structure as shown in FIG. 7, for example, has been generally used as a sheet feeder for separating supplied sheets one by one. . Here, FIG. 1A is a front view, and FIG. 1B is a side view. In the figure, reference numerals 5 and 6 denote upper and lower separation rollers, respectively, and function to separate one sheet at a time when a plurality of sheets 7 enter between them. Urethane rubber or the like having a large friction coefficient is used as a material of the separation roller.

More specifically, as shown in FIG. 1A, the separation roller 5 rotates in the direction in which paper is fed,
The sheet 7 sent from the lifting plate 8 is conveyed in a sheet feeding direction indicated by an arrow D. The lower separation roller 6 is attached to a support plate 9, and the support plate 9 is rotatable around a fulcrum 10. Further, the plate 13 provided on the support plate 9 is pushed in the direction of arrow E by the spring 11 attached to the side plate 12 on the apparatus main body side, whereby the lower separation roller 6 is pressed in the direction of arrow C.

As shown in FIG. 1B, a spacer 14 is provided below the separation roller 6, and when the spacer 14 comes into contact with the upper separation roller 5, the nip amount between the upper and lower separation rollers is reduced. Decided. The spacer 14 is made of ABS resin or the like, and has a very small surface friction coefficient as compared with the urethane rubber or the like. Therefore, it can be considered that the spacer 14 itself hardly affects the conveyance of the paper 7.

The lower separation roller 6 separates a plurality of sheets 7 that have entered between the upper and lower separation rollers one by one in a stationary state or in a state of rotating in the reverse direction of sheet feeding. When the separation roller lower 6 only needs to be stationary, a fixed pad may be used instead of the roller, and when it is necessary to rotate the sheet in the reverse direction, a separate driving means is added. Needless to say. Usually, when the lower separating roller 6 is used in a stationary state, it is attached to the support plate 9 via a one-way bearing so that the lower roller 6 can rotate freely only in the reverse direction of the sheet feeding. It is designed to rotate the paper in the reverse direction by a fixed amount during lifting and lowering to prevent uneven wear on the surface.

As described above, in the prior art, the nip amount between the upper and lower separation rollers is set to the fixed state as described above, and the sheet is separated.

[0007]

However, in the above-mentioned prior art, the paper 7 of the paper 7 adheres to the surface of the upper and lower separation rollers 5, 6, the surface is worn, and the environment such as temperature, humidity, etc. The state of the surface of the separation roller due to the influence of the change, the friction coefficient of the surface of the sheet 7 changes, the environmental change such as temperature and humidity, and the influence of the static electricity, etc. Due to the state change, the frictional force between the separation roller and the sheet 7 changes. As a result, for example, when the frictional force between the separation roller and the paper 7 is reduced, double feed occurs (a plurality of papers are fed at a time), and when the frictional force is increased. There is a situation where no paper feed occurs.

That is, the amount of nip between the separation rollers that determines the frictional force between the separation roller and the paper 7 is determined at the design stage, and even if the above-described state change occurs, the nip amount is adjusted accordingly. Since the amount cannot be adjusted, the frictional force changes under the influence of the state change, causing a jam (paper jam) and the above-described misfeed. An object of the present invention is to solve these disadvantages and to provide a paper feed separation device capable of controlling the nip amount with high accuracy by using a simple mechanism and a control method to suppress the occurrence of the jam and the misfeed. And

[0009]

In order to achieve the above object, according to the present invention, there is provided a first separation roller and a second separation roller arranged opposite to the first separation roller. A sheet separating device for separating and transporting a plurality of sheets that have entered between the first separation roller and the second separation roller one by one, comprising a support member; Is provided on the support member, and a driving means is provided for driving the support member in a rotational direction about a rotation axis on the support member separated by a predetermined distance from the second separation roller.

Specifically, the driving means is a stepping motor of a type in which a motor shaft moves in an axial direction, and drives the support member in conjunction with the motor shaft.

Further, the paper separating apparatus is provided with a non-paper detecting sensor for detecting that the paper is not fed, and when detecting the non-paper feeding, the second separating roller is driven by the first separating roller. The support member is driven by the drive unit in a direction away from the separation roller. Further, the paper feed / separation device is provided with a double feed detection sensor for detecting that a plurality of papers have been fed at the same time, and when the double feed is detected, the second separation roller is set to the first feed roller. The supporting member is driven by the driving means in a direction approaching the separation roller.

Further, the driving of the support member by the driving means can be performed based on a physical quantity caused by a use environment of the sheet feeding / separating apparatus.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a basic configuration of a sheet feeding / separating apparatus of the present invention, and FIG.
Is a front view, and FIG. 2B is a side view. In FIG. 1, reference numeral 1 denotes a so-called stroke type stepping motor (hereinafter referred to as a motor) in which a motor shaft moves in an axial direction, and 2 denotes the motor shaft. As shown in the drawing, the paper feed / separation device of the present invention connects the motor 1 to the support plate 9 of the conventional paper feed / separation device as shown in FIG. It is in the shape that was made.

The motor 1 is fixed to the apparatus main body side by a bracket 3, and when the motor 1 is driven, the motor shaft 2
Moves in the direction of arrow A, and rotates the support plate 9 around the fulcrum 10 via the L-shaped plate 4.
Direction, and the distance between the upper and lower separation rollers changes. By controlling this, the nip amount between the separation rollers is adjusted. Note that the sheet feeding operation itself is the same as the content described with reference to FIG.

FIG. 2 is a diagram schematically showing a state in which a control circuit is connected to the motor 1. In the figure, 15 is a motor drive board, and 16 is a microcomputer board. The control of the motor 1 is performed using a one-chip microcomputer. The control pulse of the motor generated by the microcomputer on the microcomputer board 16 is divided into phases by the phase control circuit of the motor drive board 15, and the controlled excitation pulse is given to the motor 1 by the motor drive circuit, and the motor 1 is driven. You. The control pulse generated by the microcomputer is generated with one pulse as a minimum unit, and the motor moves by the generated pulse.

Hereinafter, in this embodiment, the motor 1 is
This shows a control value when only the pulse is controlled. However, it is a reference value when the type of the motor and other configurations are limited. Here, the pulling force refers to a force measured when a sheet sandwiched between the separation rollers is pulled at a constant speed in a sheet feeding direction by a spring scale or the like. The force can also be controlled. At this time, the motor is stopped, and the separation roller,
The frictional force between the sheets and the holding force of the motor are the pulling resistance. The force for separating the paper can be determined based on the magnitude of the pulling force.

Motor axis movement amount: 0.025 mm / 1 pulse (Control resolution: 0.025 mm / stroke 1.5 mm
= 1/60) Pulling force: 4.33 g / 1 pulse (Control resolution: 4.33 g / Control width 260 g = 1/6)
0)

As can be seen from the above results, the use of this apparatus makes it possible to control the pulling force, that is, the separating force of the paper, with considerably high precision. FIG. 3 shows a state in which a detection sensor used for control is attached. In the figure, reference numeral 17 denotes a non-feeding detection sensor, which mainly uses a photosensor such as a reflection type photoreflector or a type in which a transmission type photointerrupter is combined with an actuator. Reference numeral 18 denotes a double feed detection sensor, which is mainly of a type that detects the double feed of the paper 7 by moving up and down a shaft with a roller at the tip when the paper 7 passes.

It should be noted that the double feed detecting sensor 18 can also serve as the non-feed detecting sensor 17. Further, the support plate 33 shown in FIG.
Is mounted at one end thereof so as to be rotatable around the axis of the separation roller 5, and the other end of the support plate 33 is
Is attached.

FIG. 4 and FIG. 5 are flowcharts for controlling the nip amount between the separation rollers. FIG. 4 shows a control operation when no paper is fed. In step P5 of FIG.
A normal paper feed operation is performed, and the paper feed roller 19 and the upper separation roller 5 rotate at a constant peripheral speed equal to each other, and feed out the paper 7 in the paper feed direction. The lower separation roller 6 stops or rotates in the reverse direction of the sheet feeding, and separates the extra fed sheet.

In parallel with the sheet feeding operation in step 5 described above,
In step P10, the paper 7 sent to the transport path 20 is detected by the no-feed detection sensor 17, and it is determined whether or not the paper is in the no-feed state by checking the paper-feeding time interval. Transition. In step P15, the motor 1 is driven in real time one pulse at a time to execute the sheet feeding operation in step P5 and the non-feeding determination in step P10 while reducing the nip amount. repeat.

FIG. 5 shows a control operation at the time of double feeding.
In step S5 of FIG. 11, a normal sheet feeding operation is performed in the same manner as in step P5, and a
, The double feed detection sensor 18 determines whether or not a plurality of sheets have been fed simultaneously, that is, whether or not it is in a double feed state, and if it is a double feed, the process proceeds to step S15. In step S15, the paper feed roller 19 is rotated in the reverse direction of the paper feed, and the paper 7 is returned to the state before the paper feed, thereby setting the paper initial state. Further, the process proceeds to step S20, in which the motor 1 is driven to increase the nip amount by a predetermined value, and the process returns to step S5 to execute the sheet feeding operation again, and repeat the try and error until a normal sheet feeding state is achieved. .

Table 1 shows the measurement results of the pulling force measured in the sheet separating apparatus according to the present invention. The measurement result of the pulling force in the sheet feeding and separating apparatus according to the prior art is 170.0.
g, and the position is shown in Table 1 as STANDARD. In the table, STEP is the number of control pulses, TENTION is the pulling force, and RATIO
Is (TENTION-STANDARD) / STAND
ARD (%) is shown.

[0024]

[Table 1]

As can be seen from the table, in the sheet feeding / separating apparatus of the present invention, the pulling force is -100% to + 100% of the standard value.
It can be changed in the range of about 53%, and a wide range and flexible response are possible. Note that the above data is only an example, and is a case where the movable range of the motor 1 is limited.
It is of course possible to change the above values by changing the structure and the like of the paper feed separation device. In addition, by using a sensor for detecting environmental changes such as temperature and humidity, that is, a disturbance, it is possible to set an optimum nip amount for the environment. For example, when the humidity is low, the surface of the separation roller is dried and the frictional force with the paper is reduced. Therefore, the nip amount of the separation roller may be increased to increase the frictional force with the paper.

FIG. 6 is a diagram showing an overall mechanism configuration of the sheet feeding / separating apparatus of the present invention. In the figure, a mechanism for controlling the nip amount is shown as a unit 30. Also,
Reference numeral 21 denotes a paper feed motor serving as a driving source when the paper 7 is conveyed.
The rotation is transmitted to the pulley and gear 24 by the belt 22 and further transmitted to the shaft 27 or 27 ′ from the gear 25 via the clutch 26.

The shaft 27 rotates the coaxial separation roller 5, and feed rollers 1 through a group of pulleys and belts 28.
Rotate 9 On the other hand, the shaft 27 'is structured to rotate the lower separation roller 6 via the gear group 29. Further, by detecting the bar 32 provided on the support plate 9 by the sensor 31, the home position when the motor 1 is driven, that is, the reference position of the 0 pulse is determined.

[0028]

As described above, according to the present invention, the first
, And a second separation roller arranged opposite to the first separation roller, and the first separation roller and the second separation roller
A sheet separating device that separates and conveys a plurality of sheets that have entered between the separation rollers one by one, including a support member, and providing the second separation roller on the support member; A driving means is provided for driving the support member in the rotational direction about a rotation axis on the support member that is separated from the second separation roller by a predetermined distance.

Specifically, the driving means is a stepping motor of a type in which a motor shaft moves in an axial direction, and drives the support member in conjunction with the motor shaft. According to this configuration, the nip amount between the separation rollers can be controlled with high accuracy by a simple mechanism, and it is possible to prevent a feeding failure such as double feeding or no feeding.

Further, the paper separating device is provided with a non-paper feeding detecting sensor for detecting that the paper is not fed, and when the paper non-feeding is detected, the second separating roller is moved to the first separating roller. The support member is driven by the drive unit in a direction away from the separation roller. Further, the paper feed / separation device is provided with a double feed detection sensor for detecting that a plurality of papers have been fed at the same time, and when the double feed is detected, the second separation roller is set to the first feed roller. The supporting member is driven by the driving means in a direction approaching the separation roller. According to this configuration, it is possible to set an optimum nip amount between the separation rollers.

The driving of the support member by the driving means can be performed based on a physical quantity caused by a use environment of the sheet separating device. According to this configuration, it is possible to set an optimum nip amount between the separation rollers in the use environment.

[Brief description of the drawings]

FIG. 1 is a diagram showing a basic configuration of a paper feed / separation device of the present invention.

FIG. 2 is a diagram schematically showing a state in which a control circuit is connected to a motor.

FIG. 3 is a diagram showing a state where a detection sensor used for control is attached.

FIG. 4 is a flowchart illustrating a control operation when no paper is fed.

FIG. 5 is a flowchart showing a control operation at the time of double feeding.

FIG. 6 is a diagram showing an overall mechanism configuration of the sheet feeding / separating apparatus of the present invention.

FIG. 7 is a diagram showing a basic configuration of a conventional paper feed / separation device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 motor 2 motor shaft 3 bracket 4 L-shaped plate 5 upper separating roller 6 lower separating roller 7 paper 8 elevating plate 9 support plate 10 fulcrum 15 motor drive board 16 microcomputer board 17 non-feed detection sensor 18 double feed detection sensor 20 transport path

Claims (5)

[Claims] A first separation roller and a second separation roller disposed opposite to the first separation roller, wherein a first separation roller and a second separation roller are disposed between the first separation roller and the second separation roller. In a paper feed separation device that separates and transports a plurality of invading sheets one by one, the paper separation device includes a support member, the second separation roller is provided on the support member, and the second separation roller is A sheet separating apparatus comprising: a driving unit that drives the support member in a rotational direction about a rotation axis on the support member that is separated by a predetermined distance. 2. The feeding device according to claim 1, wherein the driving means is a stepping motor of a type in which a motor shaft moves in an axial direction, and drives the support member in conjunction with the motor shaft. Paper separation device. 3. The paper feeding / separating device further includes a paper-free detecting sensor that detects that paper has not been fed, and when the paper-feeding is detected, the second separation roller causes the first separating roller to rotate. The paper feed separation device according to claim 1, wherein the support member is driven by the driving unit in a direction away from the separation roller. 4. A multi-feed detection sensor for detecting that a plurality of papers have been fed at the same time, wherein the multi-feed detection sensor detects that the multi-feed has occurred. First
The paper feed separation device according to any one of claims 1 to 3, wherein the support member is driven by the driving means in a direction approaching the separation roller. 5. The feeding device according to claim 1, wherein the driving of the supporting member by the driving unit is performed based on a physical quantity caused by a use environment of the sheet separating device. Paper separation device.