JPH10279100A - Automatic document feeder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dispense with a driving mechanism exclusively used for a paper supply member, and simplify the structure of the paper supply member, by installing a power transmitting mechanism between an endless belt and the paper supply member, and transmitting the driving force of the endless belt to a paper supply part through the power transmitting mechanism. SOLUTION: A driving roller 52 and a driven roller 53 are mounted on a holding bracket 51, and a paper supply belt 11 is wound on the outer peripheral faces of the same. A paper supply motor is connected to a driving shaft 52a of the driving roller 52 through a driving system, and the driven roller 53 is rotated through the driving roller 52 and the paper supply belt 11. An oscillating arm 56 is installed on an outside of one side face of the belt holding bracket 51, and the first arm shaft and the second arm shaft are installed, so that the driven roller is slidably inserted into the first arm shaft, and an access roller 10 is slidably inserted into the second arm shaft. An idler gear 59 is rotatably mounted between the first arm shaft and the second arm shaft, and the idler gear 59 is engaged with the gears 10a, 53a formed on the edge parts of the access roller 10 and the driven roller 53.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic document feeder provided in an image processing apparatus such as a copying machine, a facsimile machine, a printer, a scanner, and the like. The present invention relates to an automatic document feeder having separation means for separating sheets one by one and conveying the sheets to an exposure position.

[0002]

2. Description of the Related Art Recently, image processing apparatuses such as copiers, facsimile machines, printers, and scanners have been required to have higher speeds, more functions, and lower costs. Accordingly, the cost of an automatic document feeder (hereinafter, simply referred to as an ADF) provided in the image processing apparatus has been further demanded.

[0003] Such an ADF has a call roller for contacting a document bundle composed of a plurality of documents placed on a document table and feeding an upper-layer document from the document bundle.
The document bundle fed by the call roller is separated by separating means. In particular, an ADF that separates the top document from a document bundle placed on the document table
In this case, an endless paper feed belt is exclusively used as a separating unit with the intention of reducing the contamination of the original by increasing the nip portion of the separating unit.

[0004] The calling roller and the paper feed belt are driven by separate driving means. In particular, a simple timing belt is used for the calling roller.

[0005]

However, in such a conventional automatic document feeder, the feeding roller and the paper feed belt are driven by separate driving means, so that the document bundle is supplied. The mechanism for the paper and the separation becomes complicated, resulting in an increase in the cost of the ADF.
There was a problem that the work of assembling to the F body became troublesome.

Accordingly, the present invention allows the driving force to be transmitted directly from the separating means to the sheet feeding member, thereby reducing the number of parts of the sheet feeding member, simplifying the structure, and reducing the cost. It is an object of the present invention to provide an automatic document feeder that can perform assembling easily.

[0007]

According to the first aspect of the present invention,
In order to solve the above-mentioned problems, a sheet feeding member that contacts a document bundle including a plurality of documents placed on a document table and feeds a document located at an upper layer from the document bundle, and a document feeder An endless belt that circulates in the direction and a separation preventing member that slides in contact with the endless belt and moves in a direction to separate the original. Separation means for separating the document, and a power transmission mechanism provided between the endless belt and the paper feeding member, and the driving force of the endless belt is supplied to the paper feeding member via the power transmission mechanism. It is characterized by being transmitted.

In this case, a dedicated driving mechanism for driving the sheet feeding member can be dispensed with, the number of parts of the sheet feeding member can be reduced, and the configuration can be simplified. As a result, the cost of the ADF can be reduced.
Can be easily assembled. According to a second aspect of the present invention, in order to solve the above-mentioned problem, in the first aspect of the present invention, the sheet feeding member is provided so as to be able to contact and separate from the document bundle, and the endless endless belt is provided. A drive roller provided on the inner peripheral surface of the endless belt to transmit the driving force to the endless belt by bridging the endless belt, and a driven roller rotating along with the endless belt, and the power transmission mechanism includes: The paper feed member is supported so as to be swingable about the axis of the driven roller as a rotation center, so that the paper feed member can be brought into contact with and separated from the document bundle.

In this case, since the paper feed member is supported so as to be swingable about the axis of the driven roller, the distance between the driven roller and the paper feed member when the paper feed member comes into contact with or separates from the original bundle. Can always be kept constant. For this reason, as a power transmission mechanism for transmitting power from the driven roller to the sheet feeding member, it is only necessary to provide a simple component such as an idler gear between the driven roller and the sheet feeding member, thereby further reducing the cost of the ADF. In addition, the workability of assembling the endless belt and the sheet feeding member can be further improved.

According to a third aspect of the present invention, in order to solve the above problems, in the first or second aspect of the invention, the endless belt is provided on an elastic member and an inner peripheral surface of the elastic member. It is characterized by a double structure comprising a reinforcing member for reinforcing the strength of the elastic member. In this case, when the thickness of the elastic member is constant, the stiffness of the endless belt can be adjusted by adjusting the thickness of the reinforcing member. Specifically, when the thickness of the endless belt is large and its stiffness is large, the endless belt becomes wavy and the like, and the tension cannot be set to the target tension, and the endless belt is separated from the endless belt. The contact angle with the blocking member cannot be set to the desired angle, and the document separation performance is greatly reduced. Further, when the thickness of the endless belt is small and its stiffness is small, the durability of the endless belt is reduced, and the tension is reduced to deteriorate the separating performance of the document.

In the present invention, the endless belt has a double structure of an elastic member and a reinforcing member, and the thickness of the reinforcing member is adjusted, so that the stiffness of the endless belt can be adjusted to a target value. Separation performance and durability can be improved, and strength at the time of power transmission can be ensured. Furthermore, if the strength of the reinforcing member is increased, the elastic member can be made thinner, so that the cost of the endless belt itself can be reduced.

According to a fourth aspect of the present invention, in order to solve the above-mentioned problems, in the first aspect of the present invention,
The endless belt is characterized in that teeth are formed on part or all of the inner peripheral surface, and teeth that mesh with the teeth are formed on the driving roller and the driven roller that face the teeth. In this case, the endless belt can be reliably prevented from slipping with respect to the driving roller and the driven roller, and the power can be reliably transmitted from the endless belt to the sheet feeding member via the power transmission mechanism. .

[0013]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 8 are views showing an embodiment of an automatic document feeder according to the present invention. In the present embodiment, an example is shown in which the automatic document feeder of the present invention is mounted on a copying machine as an image processing apparatus, but the image processing apparatus may be a facsimile apparatus, a printer, a scanner, or the like, in addition to the copying machine. It can be applied to devices and the like.

First, the configuration will be described. 1 and 2, reference numeral 1 denotes a copying machine, and a contact glass 2 is provided on an upper surface of the copying machine 1. An ADF 3 is provided at the upper part of the copying machine 1, and the ADF 3 is connected to the copying machine 1 via a hinge (not shown) so as to open and close the contact glass 2. The ADF 3 includes a document tray 4 serving as a document table on which a document bundle P including a plurality of documents can be placed, and a document separated from the document bundle placed on the document tray 4 one by one on the contact glass 2. Separating / feeding means 5 for transporting the document toward the contact glass 2 by the separating / feeding means 5 to transport / stop the original to an exposure position on the contact glass 2; Copier 1 installed
Reading means (known exposure lamp, mirror, lens, CC
D, etc.), a loading / unloading unit 6 for unloading the original which has been read out from the contact glass 2, and a loading / unloading unit 6.
The original discharged from the exposure position of the contact glass 2 by the first discharge tray 8 protruding from the side of the copying machine 1 or the second discharge tray 9 disposed below the document tray 4
And a paper discharging means 7 for discharging paper to either one of them. The first paper discharge tray 8 may be provided so as to protrude from the side of the ADF 3.

The separating / feeding means 5 includes a calling roller (feeding member) 10, a feeding belt (endless belt) 11, a reverse roller (separation preventing member) 12, a stop claw 14, a pullout drive roller 13, and a pullout driven. It comprises a roller 13a and a registration sensor 15. These call rollers 10,
The paper feed belt 11, the reverse roller 12, and the pull-out drive roller 13 are driven by a paper feed motor 100, and are connected to the paper feed motor 100 via a drive system such as a gear mechanism. In the present embodiment, of the separating / feeding means 5, the feeding belt 11 and the reverse roller 12 constitute the separating means.

The paper feed motor 100 is driven by an output signal from a controller 101. When a paper feed start signal is input from the copying machine 1, the controller 101 drives the paper feed motor 100 to rotate in a forward / reverse direction. It is supposed to. When the paper feed motor 100 is driven to rotate forward, the call roller 1
0 rotates clockwise to feed the upper document from the document bundle P, and the paper feed belt 11 and the reverse roller 12 rotate clockwise to separate only the top document from the document bundle P. Is done. The separated document is sandwiched between a pull-out driving roller 13 that rotates counterclockwise and a pull-out driven roller 13a that rotates with the pull-out driving roller 13a, and a paper feed belt
It is pulled out from the reverse roller 11 and the reverse roller 12 and is conveyed toward the contact glass 2.

When the leading edge of the original is detected by the registration sensor 15, the controller 101
The paper feed motor 100 is driven to rotate in the reverse direction based on the output signal from. At this time, the feed roller 10 and the feed belt 11 are stopped by a drive system interposed between the feed motor 100 and the feed roller 10, the feed belt 11, the reverse roller 12, and the pull-out drive roller 13, and the pull-out drive roller 13 is continuously rotated counterclockwise and the reverse roller
By continuing the clockwise rotation of the document 12, the following document is prevented from entering the nip portion between the sheet feeding roller 12 and the reverse roller 12, and is not separated.

The reverse roller 12 is provided with a torque limiter (not shown). The torque limiter is connected to the reverse roller 12 when only one document enters the nip between the feed belt 11 and the reverse roller 12. 12
Since the load increases with an increase in the friction coefficient, the load in the forward direction (counterclockwise in FIG. 2) rotates and when two or more sheets enter, the load on the document and the reverse roller 12 decreases. It rotates in the reverse direction (clockwise in FIG. 2).

The stopper claw 14 is provided on the downstream side of the sheet feeding belt 11 in the document conveying direction. The stopper claw 14 comes into contact with the leading end of the document bundle P so that the document bundle P It is to prevent entering the side. The stopper claw 14 is driven by a swing solenoid 105, and the swing solenoid 105 is
The stopper claw 14 is turned on / off based on an output signal from the controller 10 to move the stopper claw 14 between a contact position where it comes into contact with the leading end of the document bundle P and a retract position where it retracts upward from this position.

Here, the configurations of the call roller 10 and the paper feed belt 11 will be described in detail with reference to FIGS. Paper feed belt
Numeral 11 is housed in a belt holding bracket 51. A driving roller 52 is mounted on one end of the holding bracket 51, and a driven roller 53 is mounted on the other end. The drive roller 52 and the driven roller 53 are provided on the inner peripheral surface of the feed belt 11 and bridge the feed belt 11. The feed motor 100 is connected to the drive shaft 52a of the drive roller 52 via the drive system described above, and the driving force of the feed motor 100 is transmitted to the drive roller 52 via the drive system and the drive shaft 52a. Then, the paper feed belt 11 rotates and the driven roller 53 rotates with the paper feed belt 11.

A one-way clutch may be interposed between the drive shaft 52a and the drive roller 52 in consideration of the ability to remove the jam of the original, but functionally, the drive shaft 52a and the drive roller 52
The drive shaft 52a and the drive roller 52 may be provided integrally without interposing a one-way clutch. A driven roller shaft is provided on the inner peripheral portion of the driven roller 53.
The driven roller shaft 54 is a swing arm.
It is slidably inserted into a first arm shaft 55 provided integrally with 56. Further, both ends of the driven roller shaft 54 are provided with slits 51 a provided on both side surfaces of the belt holding bracket 51.
(Only one is shown in FIG. 5), and a pair of springs 57 is provided between both ends of the driven roller shaft 54 and the end surface of the slit 51a. The spring 57 presses both ends of the driven roller shaft 54 toward the opening of the slit 51a, thereby pressing the paper feed belt 11 and applying a constant tension to the paper feed belt 11.

The oscillating arm 56 is disposed outside one side of the belt holding bracket 51 and has a first arm shaft 55 at one end and a second arm shaft 58 at the other end. The call roller 10 is slidably inserted through the second arm shaft 58. An idler gear 59 is rotatably provided between the first arm shaft 55 and the second arm shaft 58. The idler gear 59 is provided with gears 10a, 53a formed at the ends of the call roller 10 and the driven roller 53. , The driving force of the paper feed belt 11 is transmitted from the driven roller 53 to the call roller 10.

A pressing piece 56a is provided at the end of the swing arm 56.
The pressing arm 56a is brought into contact with a solenoid arm, cam, or the like (not shown) to swing the swing arm 56a counterclockwise.
For this reason, when the swing arm 56 swings about the axis of the driven roller 53 as the center of rotation, the retrieving roller 10 comes into contact with the document bundle P and is separated therefrom.

Specifically, when the call roller 10 is brought into contact with the original bundle P, the driving force is transmitted to the call roller 10 via the idler gear 59 when the driven roller 53 rotates clockwise. At this time, the swinging arm 56 swings about the axis of the driven roller 53 by the transmitted torque, so that the call roller 10 comes into contact with the document bundle P, while the call roller 10 is separated from the document bundle P. In some cases,
By bringing a solenoid arm, a cam, or the like into contact with the pressing piece 56a, the swing arm 56 swings counterclockwise about the axis of the driven roller 53 as a center of rotation, thereby separating the calling roller 10 from the original bundle P. It is made to let.

When the call roller 10 abuts against the document bundle P, the document bundle P is pressurized by the weight of the call roller 10 and the weight of the second arm shaft 58. Alternatively, the call roller 10 may be pressed by a spring or the like. In the present embodiment, the first arm shaft 55, the swing arm 56, the second arm shaft
The 58 and the idler gear 59 constitute a power transmission mechanism.

On the other hand, the feed belt 11 has a double structure as shown in FIG. That is, the paper feed belt 11 is provided with an elastic member 11 a such as rubber for transporting a document on an outer peripheral surface, and a belt 11 on the inner peripheral surface of the elastic member 11.
Is provided with a cloth member (reinforcing member) 11b made of polyester, which can reduce the thickness and has sufficient strength. The inner peripheral surface of the cloth-like member 11b is coated with an elastic member such as rubber,
Paper feed belt 11 by adjusting the frictional force against
Can be prevented from slipping with respect to the driving roller 52 and the driven roller 53, and the paper feed belt 11 can be prevented from being biased in the width direction with respect to the driving roller 52 and the driven roller 53.

Referring again to FIG. 1, a reversing path 42 composed of a pair of curved guide plates 42a and 42b is provided between the sheet feeding belt 11, the reverse roller 12, and the contact glass 2. The document separated by the reverse roller 12 is transported along the reversing path 42. On the other hand, the loading / unloading means 6 includes a transport belt 16 and the transport belt 16.
And a plurality of pressure rollers 19 provided inside the conveyor belt 16 and pressing the conveyor belt 16 against the contact glass 2. ing.

The transport belt driving roller 17 is driven by a transport belt motor 102. When the registration sensor 15 detects the leading edge of the document as described above, the motor 102 responds to a signal from the controller 101. The original is driven forward to drive the transport belt 16 via the driving roller 17 to move the original to the contact glass 2.
It is designed to be transported upward.

The controller 101 is provided with the registration sensor 1
5 detects the trailing edge of the document, counts the number of rotation pulses of the conveyance belt motor 102 from the time of detection, and stops the driving of the driving roller 17 when the rotation pulse reaches a predetermined value. Is stopped at the exposure position on the contact glass 2. Further, when the trailing edge of the original is detected by the registration sensor 15, the controller 101 drives the paper feed motor 100 again, separates the subsequent original as described above, and conveys the original toward the contact glass 2. When the pulse of the paper feed motor 100 from the time when the original is detected by the registration sensor 15 reaches a predetermined pulse, the paper feed motor 100 is stopped and the next original is put on standby.

When the document stops at the exposure position of the contact glass 2, the copying machine 1 reads and exposes the document. When the reading and the exposure are completed, a signal is input from the copying machine 1 to the controller 101. When the signal is input, the controller 101
The transport belt motor 102 is driven to rotate forward, and the transport belt 16 transports the original from the contact glass 2 to the paper discharge unit 7.

The paper discharge means 7 includes a reverse drive roller 20, a paper discharge driven roller 21, a reverse guide roller 22, a reverse driven roller 23,
It comprises a first switching claw 24, a second switching claw 25, a paper discharge drive roller 26, a paper discharge driven roller 27, a reversing sensor 28 and a reversing sensor 29, and a reversing drive roller 20, a reversing guide roller 22 and a paper discharge driving roller 26. Are driven by a paper discharge motor 103.

The first switching claw 24 is driven to be switched by a first solenoid 106, and when a single-sided original is discharged, a home position (switching claw) for communicating the contact glass 2 with the first discharge tray 8 is provided. 24 constitutes a part of the document conveyance path). When the controller 101 is in the one-sided mode in which a normal one-sided document is conveyed (the initial setting is set to the one-sided mode even when the one-sided mode is not designated by the operation unit 108 provided in the copying machine 1). The first switching claw 24 is made to stand by at the home position without driving the 106, and the paper discharge motor 103 is driven at the same time as the transport belt motor 102 is driven after the reading of the document and the exposure are completed. For this reason, the reversing drive roller 20 and the discharge driven roller
The document nipped by 21 is discharged straight to the first discharge tray 8 without turning over the front and back surfaces.

On the other hand, the controller 101 drives the first solenoid 106 to reverse the first switching claw 24 from the home position to the contact glass 2 when the double-sided mode is designated by the operation unit 108 provided in the copying machine 1. Route 30
To the communication position (as shown in FIG. 1, the upper surface of the switching claw 24 constitutes a part of the document conveyance path).
After the reading of one side of the double-sided document and the exposure are completed, the transport belt motor 102 is driven and the paper discharge motor 103 is driven at the same time. For this reason, the document is guided to the reversing path 30 sandwiched between the reversing drive roller 20 and the discharge driven roller 21, and is conveyed toward the second switching claw 25 by the reversing guide roller 22.

The second switching claw 25 is driven by a second solenoid 107, and is not driven by the second solenoid 107 when a document whose one side has been read is carried out of the contact glass 2. At the home position where the return path 31 provided between the reversing path 30 and the contact glass 2 is opened (the second switching claw as shown in FIG. 1).
The lower surface of the document 25 is configured to be a part of a document conveyance path).

For this reason, the original conveyed out of the contact glass 2 is conveyed to the reversing path 30 by the first switching claw 24 and then reversed by the second switching claw 25 to the return path 31 with the front and back surfaces reversed. Drive roller 20 and reverse driven roller
23 and returned to the contact glass 2. When the leading edge of the document is detected by the reversing sensor 28 provided on the reversing path 30, the controller 101
02 is driven in reverse to drive the transport belt 16 in reverse, and when the rotation pulse of the transport belt motor 102 from the time when the leading edge of the document is detected by the reverse sensor 28 reaches a predetermined value, the document is placed on the contact glass 2. It is determined that the sheet has been transported to the exposure position, and the transport belt motor 102 is stopped.

When the reading and exposure of the original document are completed at the exposure position, a signal is input from the copying machine 1 to the controller 101. When the signal is input, the controller 101 drives the transport belt motor 102 to rotate forward, and furthermore, , First
The driving of the solenoid 106 and the driving of the second solenoid 107 are stopped, the first switching claw 24 allows the contact glass 2 to communicate with the reversing path 30, and the second switching claw 25 causes the reversing path 31 and the second discharge tray 9 to communicate. (The upper portion of the second switching claw 25 forms a part of the document conveyance path), and the document conveyed from the contact glass 2 is conveyed while being nipped by the reversing drive roller 20 and the reversing driven roller 21. After that, the discharge drive roller 26 and the discharge driven roller 27
And is discharged onto the second discharge tray 9.

The copying machine 1 and the ADF 3 are connected via interfaces 109 and 110, and a copy start signal and a restart signal from the copying machine 1 are input to the controller 101 via the interfaces 109 and 110. It has become. Next, the operation will be described. In the present embodiment, as described above, single-sided and double-sided originals can be transported, but only single-sided original transport will be described.

First, when the original bundle P is set on the original tray 4, the leading end of the original bundle P comes into contact with the stopper claw 14 and the movement of the original bundle P toward the paper feed belt 11 is restricted. In order to transport a document in the single-sided document transport mode, a document bundle P including a plurality of single-sided documents is placed on the document tray 4 in a state where the operator does not press the selection switch of the operation unit 108, and the copying machine 1 When a start switch (not shown) is pressed, the copier 1
A paper feed start signal is input to DF3.

At this time, the drive of the swing solenoid 105 is stopped by the controller 101, and the stopper claw 14 is retracted upward from the leading end position of the document bundle P. Next, when the controller 101 drives the paper feed motor 100, the paper feed motor
The driving force of 100 is transmitted to the driving roller 52 via the driving system and the driving shaft 52a. At this time, the drive roller 52 moves the paper feed belt 11 in a clockwise direction to rotate the driven roller 53 in a clockwise direction. Since the driving force of the driven roller 53 is transmitted to the calling roller 10 via the idler gear 59, the swinging arm 56 swings about the axis of the driven roller 53 by the torque transmitted at this time. As a result, the calling roller 10 comes into contact with the document bundle P.

For this reason, the uppermost original is fed from the original bundle P by the call-up roller 10, and the uppermost original is separated by the feed belt 11 and the reverse roller 12 as described above. The separated document is sandwiched between a pull-out driving roller 13 rotating in a counterclockwise direction and a pull-out driven roller 13a rotating with the pull-out driving roller 13, pulled out from the paper feeding belt 11 and the reverse roller 12, and conveyed toward the contact glass 2. You.

Next, when the registration sensor 15 detects the leading edge of the document, the controller 101 determines whether or not there is a next document based on a detection signal from a document set sensor (not shown) provided on the document tray 4. If there is a next document, the controller 101 drives the solenoid or cam to contact the pressing arm 56a with the arm or cam of the solenoid, so that the swing arm 56 is rotated about the axis of the driven roller 53 as the rotation center. By swinging in the counterclockwise direction, the calling roller 10 is separated from the original bundle P,
100 is driven to rotate in the reverse direction, and the transport belt motor 102 is driven to rotate in the forward direction.

At this time, the feed motor 100 and the call roller 1
0, the feeding roller 10 and the feed belt 11 are stopped by the drive system interposed between the feed belt 11, the reverse roller 12, and the pull-out drive roller 13, and the pull-out drive roller
13 is continuously rotated counterclockwise and the reverse roller 12 is continuously rotated clockwise,
Subsequent documents are prevented from entering the nip portion between the feed belt 11 and the reverse roller 12 so as not to be separated.

When the registration sensor 15 detects the trailing edge of the document during this conveyance, the controller 101 counts the rotation pulses of the conveyance belt motor 102 from the time of this detection, and
When the rotation pulse reaches a predetermined value, the driving of the driving roller 17 is stopped to stop the transport belt 16, thereby stopping the original at the exposure position on the contact glass 2. When the original stops at the exposure position of the contact glass 2, the copying machine 1 reads and exposes the original. When the reading and the exposure are completed, the controller 101 is connected to the controller 101 via the interfaces 109 and 110.
Restart signal is input from the
When this signal is input, the transport belt motor 102 is driven to rotate forward, and the transport belt 16 transports the original from the contact glass 2 to the paper discharge means 7.

At this time, since the first switching claw 24 is waiting at the home position, the controller 101 drives the transport belt motor 102 after the completion of the reading of the original and the exposure, and at the same time, drives the discharge motor 103. . For this reason, the document sandwiched between the reversing drive roller 20 and the discharge driven roller 21 is discharged straight to the first discharge tray 8 without reversing the front and back surfaces.

When a feed start signal for the next original is input, the feed motor 100 is driven again, the driving of the solenoid and the driving cam is stopped, and the driven roller 53 is driven through the idle gear 59 through the idle gear 59. The swing arm 56 is swung about the axis of the driven roller 53 as the center of rotation by the transmission torque transmitted to the
Therefore, the retrieving roller 10, the paper feed roller 11, and the like are driven to separate the subsequent document as described above and convey it toward the contact glass 2 to continue the above-described processing.

As described above, in this embodiment, the sheet feeding belt 11
An idler gear 59 held by a swing arm 56 is interposed between the ringing roller 10 and the driving force of the paper feed belt 11 is transmitted to the ringing roller 10 via the idler gear 59, so that the driving roller 10 is dedicated to driving the ringing roller 10. The drive mechanism can be dispensed with, the number of parts of the call roller 10 can be reduced, and the configuration can be simplified. As a result, the cost of the ADF 3 can be reduced, and the paper feed belt 11 and the call roller 10 can be united with the idler gear 59 and easily assembled to the ADF 3.

Further, the call roller 10 is brought into contact with the original bundle P,
A paper feed belt 11 is provided on the inner peripheral surface of the paper feed belt 11 and a driving roller 52 that bridges the paper feed belt 11 and transmits a driving force to the paper feed belt 11, and a paper feed belt 11. The driven roller 53 is rotatably supported about the axis of the driven roller 52 as a center of rotation, so that the driven roller 53 can be brought into contact with and separated from the original bundle P. The distance between the driven roller 53 and the call roller 10 can be kept constant at all times when the sheet 10 comes into contact with or separates from the document bundle P. For this reason, it is only necessary to provide an idler gear 59 having a simple structure between the driven roller 53 and the paging roller 10 as a power transmission mechanism for transmitting power from the driven roller 53 to the paging roller 10, thereby reducing the cost of the ADF 3. In addition to further reduction, the workability of assembling the sheet feeding belt 11 and the call roller 10 can be further improved.

The paper feed belt 11 is provided on an elastic member 11a and an inner peripheral surface of the elastic member 11a.
In this case, the elasticity of the elastic member 11a is made constant, and the thickness of the cloth-like member 11b is adjusted to adjust the stiffness of the feed belt 11 when the elastic member 11a has a constant thickness. be able to. Specifically, the feed belt 11
If the thickness of the paper feed belt 11 is large and its stiffness is large, the paper feed belt 11 becomes wavy or the like, and the tension cannot be set to the target tension, and the contact angle between the paper feed belt 11 and the reverse roller 12 Cannot be set to the desired angle, and the separation performance of the document is greatly reduced. Further, when the thickness of the paper feeding belt 11 is small and its stiffness is small, the durability of the paper feeding belt 11 is reduced, and the tension is reduced, so that the separating performance of the document is deteriorated.

In this embodiment, the paper feed belt 11 is
By adjusting the thickness of the cloth-like member 11b by using a double structure of the cloth-like member 11a and the cloth-like member 11b, the stiffness of the paper feed belt 11 can be adjusted to a desired value, and the separation performance and durability of the document are improved. And the strength at the time of power transmission can be ensured. Furthermore, if the strength of the cloth-like member 11b is increased, the elastic member 11a can be made thinner, so that the cost of the paper feed belt 11 itself can be reduced.

In the present embodiment, the inner peripheral surface of the cloth-like member 11b constituting the paper feed belt 11 is coated with an elastic member such as rubber so that the driving roller 52 and the driven roller 52 are driven.
By adjusting the frictional force against 53, the feed belt 11 is driven
The slip is prevented from slipping on the roller 52 and the driven roller 53. However, the present invention is not limited to this, and the teeth 61 are formed on a part of the inner peripheral surface of the sheet feeding belt 11 as shown in FIG. And a driving roller 52 and a driven roller facing the teeth 61.
Teeth 62 and 63 meshing with the 61 teeth may be formed in the 53 portion. In this way, it is possible to completely prevent the paper feeding belt 11 from slipping with respect to the driving roller 52 and the driven roller 53, and to reliably feed the feeding belt 11 from the paper feeding belt 11 through the idler gear 59. Power can be transmitted to the vehicle.

Further, a part of the inner peripheral surface of the paper feeding belt 11
Instead of forming the teeth, the teeth may be formed on the entire inner peripheral surface of the feed belt 11.

[0052]

According to the first aspect of the present invention, a dedicated driving mechanism for driving the sheet feeding member can be dispensed with, the number of parts of the sheet feeding member can be reduced, and the configuration can be simplified.
As a result, the cost of the ADF can be reduced, and the endless belt and the sheet feeding member can be united with the power transmission mechanism and easily assembled to the ADF.

According to the second aspect of the present invention, the paper feed member is supported so as to be swingable about the axis of the driven roller as a center of rotation. The distance of the sheet feeding member can be always kept constant. For this reason, as a power transmission mechanism for transmitting power from the driven roller to the sheet feeding member, it is only necessary to provide a simple component such as an idler gear between the driven roller and the sheet feeding member, thereby further reducing the cost of the ADF. In addition, the workability of assembling the endless belt and the sheet feeding member can be further improved.

According to the third aspect of the invention, the endless belt has a double structure of an elastic member and a reinforcing member, and the thickness of the reinforcing member is adjusted to adjust the stiffness of the endless belt to a target one. As a result, the separation performance and durability of the document can be improved, and the strength during power transmission can be ensured. Furthermore, if the strength of the reinforcing member is increased, the elastic member can be made thinner, so that the cost of the endless belt itself can be reduced.

According to the fourth aspect of the present invention, it is possible to reliably prevent the endless belt from slipping with respect to the driving roller and the driven roller, and to feed the sheet from the endless belt via the power transmission mechanism. Power can be reliably transmitted.

[Brief description of the drawings]

FIG. 1 is a schematic view of an embodiment of an automatic document feeder according to the present invention.

FIG. 2 is a block diagram of a driving mechanism of the automatic document feeder according to the embodiment;

FIG. 3 is a schematic configuration diagram of a sheet feeding member and a separating unit according to one embodiment.

FIG. 4 is a perspective view of a separating unit, a sheet feeding member, and a power transmission mechanism of the embodiment.

FIG. 5 is a perspective view of a separating unit, a sheet feeding member, and a power transmission mechanism when the sheet feeding belt of FIG. 4 is held by a belt holding bracket.

FIG. 6 is an exploded view of a driven roller, a call roller, and a swing arm according to an embodiment.

FIG. 7 is a configuration diagram of a sheet feeding belt of one embodiment.

FIG. 8 is a diagram illustrating another mode of the sheet feeding belt, the driving roller, and the driven roller.

[Description of Signs] 3 ADF (Automatic Document Feeder) 4 Document Tray (Document Placement Table) 10 Retrieval Roller (Sheet Feeding Member) 11 Feeding Belt (Endless Belt) 11a Elastic Member 11b Cloth Member (Reinforcing Member) 12 Reverse roller (separation preventing member) 52 Drive roller 53 Follower roller 55 First arm shaft (power transmission mechanism) 56 Swing arm (power transmission mechanism) 58 Second arm shaft (power transmission mechanism) 59 Idler gear (power transmission mechanism) 61 ~ 63 teeth P Original bundle

Claims (4)

[Claims] A sheet feeding member for contacting an original bundle composed of a plurality of originals placed on an original placing table and feeding an upper-level original from the original bundle; A separation stopping member that moves in the direction of separating the original by slidingly contacting the endless belt, and separating the uppermost original from the upper-layer original fed by the paper feeding member. Means, provided with a power transmission mechanism between the endless belt and a paper feeding member, and transmitting a driving force of the endless belt to the paper feeding member via a power transmission mechanism. An automatic document feeder, characterized in that: 2. The endless belt is provided on the inner peripheral surface of the endless belt, and the endless belt is provided by bridging the endless belt. A driving roller for transmitting a driving force to the belt, and a driven roller for rotating with the endless belt, wherein the power transmission mechanism swingably supports the sheet feeding member around the axis of the driven roller as a rotation center. ,
2. The automatic document feeder according to claim 1, wherein a sheet feeding member is capable of coming into contact with and separating from said document bundle. 3. The endless belt according to claim 1, wherein the endless belt has a double structure including an elastic member and a reinforcing member provided on an inner peripheral surface of the elastic member to reinforce the strength of the elastic member. Or the automatic document feeder according to 2. 4. The endless belt has teeth formed on a part or all of an inner peripheral surface thereof, and teeth that mesh with the teeth are formed on a portion of the driving roller and a driven roller facing the teeth. 4. The automatic document feeder according to claim 1, wherein: