JP6944826B2 - Sheet transfer device and image reader - Google Patents

Description

The present invention relates to, for example, a sheet transfer device incorporated in a document scanner, a facsimile, a printer, a copying machine, etc., and an image reading device including the sheet transfer device.

As a conventional seat transfer device, for example, a medium supply device including a feed roller and a braking means that applies pressure to the feed roller to act on a medium that has entered between the feed rollers and a predetermined transport load. Is known (see Patent Document 1).

Japanese Unexamined Patent Publication No. 2014-181109

In the medium transfer device of Patent Document 1 described above, the media are handled one after another by the nip portion formed between the feeding roller and the braking means, but the media are not handled well and two or more media are overlapped. In some cases, double feeding may occur in which the paper medium is fed in a slanted state, or skewing may occur in which the medium is fed in a state of being tilted in an oblique direction, and when a paper medium is fed as a medium, the above nip The part becomes the source of paper dust.

The present invention provides a sheet transfer device and an image reading device that can more reliably realize double feed detection and skew detection.

In the present invention, there are a separate feeding unit that separates and feeds sheets one by one, a transport unit that transports the sheets separated by the separate feeding unit along a transport path, and the separate feeding unit. The separate feeding unit is provided with a sheet detecting unit that is arranged on the downstream side in the sheet feeding direction and detects the sheet, and the separated feeding unit is provided with first and second roller units at intervals on the rotation axis. And a separating portion that is contacted with a part of the feeding portion to form a nip portion with the feeding roller, and the sheet detecting portion detects the double feeding of the sheet. It has a feed detection sensor and a movement detection sensor that detects the movement of the sheet, and the double feed detection sensor and the movement detection sensor are described in the separate feed unit including a gap between the first and second roller units. in the downstream region of the front from the portion other than the nip portion reaches the a region extending in the sheet feeding direction downstream side and the conveying unit, have a test known area of the sheet, the detection region of the movement detection sensor, the It is a region different from the detection region of the double feed detection sensor, and the double feed detection sensor detects a sheet in a first downstream region extending downstream in the sheet feeding direction by the width of the gap between the first and second roller portions. The movement detection sensor has a region, and the movement detection sensor has a sheet detection region in a second downstream region extending downstream in the sheet feeding direction with a width of a portion of the feeding portion where the separating portion is not contacted. It is a feature.

According to the present invention, it is possible to realize a sheet transfer device and an image reading device that can more reliably execute double feed detection and skew detection.

Schematic cross-sectional view (conveyed state) of the document feeding device according to the first embodiment. Schematic cross-sectional view (standby state) of the document feeding device according to the first embodiment. The structural drawing of the drive transmission of the document feeding apparatus which concerns on 1st Embodiment. The enlarged view of the main part of the feeding part of the document feeding apparatus which concerns on 1st Embodiment. The schematic diagram of the feeding transport part of the document feeding apparatus which concerns on 1st Embodiment. The block diagram of the control unit which concerns on 1st Embodiment. The flowchart which shows the operation of the document feeding apparatus which concerns on 1st Embodiment. The perspective view of the feeding part which concerns on 1st Embodiment. The cross-sectional view of the feeding part which concerns on 1st Embodiment. Cross-sectional view of the other feeding section. The cross-sectional view of the feeding part which concerns on 1st Embodiment. Another cross-sectional view of the feeding section according to the first embodiment. Another cross-sectional view of the feeding section according to the first embodiment. Sectional drawing of the conventional feeding part. The cross-sectional view of the feeding part which concerns on 1st Embodiment. A front view of the feeding unit according to the first embodiment (a view seen from the mounting table in the feeding direction). A front view of the feeding unit according to the first embodiment (a view seen from the mounting table in the feeding direction). A front view of the feeding unit according to the first embodiment (a view seen from the mounting table in the feeding direction). A front view of the feeding unit according to the first embodiment (a view seen from the mounting table in the feeding direction). The cross-sectional view of the feeding part which concerns on 1st Embodiment. The cross-sectional view of the feeding part which concerns on 2nd Embodiment. A front view of the feeding unit according to the second embodiment (a view seen from the mounting table in the feeding direction). The perspective view of the feeding part which concerns on 3rd Embodiment. FIG. 3 is a cross-sectional view of a feeding unit according to a third embodiment. The schematic diagram of the feed | feed transport part which concerns on 4th Embodiment. The schematic diagram of the other feeding and transporting part which concerns on 4th Embodiment. The structural drawing of the drive transmission of the document feeding apparatus which concerns on 5th Embodiment. The structural drawing of the drive transmission of the document feeding apparatus which concerns on another embodiment. The structural drawing of the drive transmission of the document feeding apparatus which concerns on another embodiment. The perspective view which shows the schematic structure of the feeding roller which concerns on other embodiment. The structural drawing of the drive transmission of the document feeding apparatus which concerns on another embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(First Embodiment)
The first embodiment will be described with reference to FIGS. 1 to 20. FIG. 1 is a schematic view of a document feeding device A according to an embodiment of the present invention.

<Device configuration>
The document feeding device A is a device having a document transport system such as an image reading device (scanner or the like) for reading an image of a document, a printing device (printer or the like) for printing on a document, or a multifunction device combining these. In this embodiment, it will be described as an example applied to an image reader.

In the document feeding device A of the present embodiment, one or a plurality of documents S loaded on a mounting table 1 (loading unit) provided at the upper end on the back side of the device main body A1 are placed in the device one by one. This device is a device that conveys an image along a path RT inclined with respect to a horizontal plane (installation surface of the device main body A1), reads the image, and discharges the image to a discharge tray 2 provided at the lower end on the front side of the device main body A. The document S to be read is, for example, a sheet of OA paper, a check, a check, a business card, a card, or the like, and may be a thick sheet or a thin sheet. Examples of cards include insurance cards, driver's licenses, credit cards and the like.

<Supply section>
As shown in FIG. 1, a first transport unit 10 is provided as a feed mechanism for feeding the document S along the path RT of the apparatus main body A1. In the case of the present embodiment, the first transport unit 10 includes a feed roller 110 and a separation roller 12 arranged to face the feed roller 110, and the document S arranged on the loading surface side on the mounting table 1 is provided. They are sequentially conveyed one by one in the feeding direction D1.

Note that FIG. 1 shows a transport state, while FIG. 2 shows a standby state. FIG. 3 shows an enlarged view of the drive transmission structure of the entire device, FIG. 4 shows an enlarged view of a main part of the feeding unit, and FIG. 5 shows an enlarged view of a main part of the feeding / transporting unit. In the present embodiment, the feeding direction D1 is provided so as to be inclined at a predetermined angle with respect to the mounting surface of the document feeding device A, and is fed by the weight of the document S mounted on the mounting table 1. The manuscript S is supplied to the feeding mechanism.

On the upper end side of the apparatus main body A1, a roller mounting portion a1 which is a concave portion for mounting the feeding roller 110 so as to come into contact with the document S on the mounting surface side of the mounting table 1 is provided. .. In the present embodiment, a cover member a3 that covers the periphery of the feeding roller 110 mounted in the roller mounting portion a1 is provided at the end of the roller mounting portion a1 so as to be openable and closable. Then, in the state where the cover member a3 is in the open state, the feeding roller 110 is detachable from the roller mounting portion a1.

Further, as shown in FIG. 4, in the feeding roller 110, for example, two feeding roller portions (first roller portion and second roller portion) 11 formed of a rubber material or the like are individually attached to the wheel portion 111. The wheel portion 111 is mounted and is individually supported by the feed roller shaft (rotary shaft) 11b via the one-way clutch 11a. That is, the one-way clutch 11a of the present embodiment is a first one-way clutch portion and a second one-way clutch portion that are individually provided for a plurality of feeding roller portions 11 separately provided on the left and right sides and are independent of each other.

Further, as shown in FIG. 4, the feeding roller shaft 11b included in the feeding roller 110 has shaft end portions on both sides held by bearing portions a2 provided in the roller mounting portion a1, and a cover member is further provided above the bearing portion a2. By closing a3, a bearing structure of the feed roller shaft 11b is formed between the cover member a3 and the bearing portion a2 of the roller mounting portion a1, and between the bearing portion a2 in the roller mounting portion a1 and the cover member a3. Both ends of the feed roller shaft 11b are rotatably held. That is, by opening and closing the cover member a3, the feeding roller 110 can be easily attached and detached.

Further, the feeding roller shaft 11b of the feeding roller 110 is provided with a feeding gear portion 112 in a gap in the axial direction of each feeding roller portion 11. The feed gear unit 112 is gear-connected to the drive gear unit 101 that transmits the driving force of the motor 3 (drive motor) installed in the apparatus main body A1. The feed gear portion 112 has a structure in which the upper portion on the separation roller 12 side is covered by the cover member a3 when the cover member a3 is closed. As a result, the cover member a3 can protect the paper dust from adhering to the feed gear portion 112.

The feed gear portion 112 protected by the cover member a3 is provided with a gear diameter smaller than the diameter of each feed roller portion 11. Therefore, the drive gear portion 101 partially overlaps with each feed roller portion 11 in the axial direction of the feed roller shaft 11b, and the gear connection portion with the feed gear portion 112 is in the axial direction of each feed roller. It is provided so as to overlap the portion 11. As a result, the outer diameter of the feeding gear portion 112 can be set small, the accommodation capacity of the feeding roller 110 can be improved, and physical interference with the cover member a3 can be prevented.

Further, the drive gear portion 101 connected to such a feed gear portion 112 is provided on one end side of the drive gear shaft 102, and a clutch composed of an electromagnetic clutch or the like is provided on the other end side of the drive gear shaft 102. A unit 103 is provided. Further, the clutch portion 103 is connected between the drive transmission mechanism (gear train) X to which the driving force is transmitted from the motor 3 by the pulley and the drive gear shaft 102. That is, the drive gear shaft 102 and the drive transmission mechanism X are drive-connected by the clutch portion 103 of the drive gear shaft 102. Further, the drive transmission mechanism X of the separation roller 12 is connected to the drive transmission mechanism X to the feed roller 110. That is, the motor 3 serves as a drive source for the separation roller 12 and the feed roller 110.

Here, when the clutch portion 103 provided on the drive gear shaft 102 is OFF, the reverse drive of the motor 3 (drive for returning the document to the mounting table 1 side) is not transmitted to the drive gear shaft 102, and the clutch portion 103 When is ON, it is a switching means for transmitting only the forward rotation drive of the motor 3 (drive in the direction of separating and feeding the document) to the drive gear shaft 102.

When the clutch portion 103 is turned off, drive transmission is performed only to the separation roller 12, and at this time, the feeding roller 110 is driven to rotate by the separation roller 12. As a result, when the double feed detection sensor 40, which will be described later, detects that the document has been double-fed, the feeding operation is temporarily stopped and the motor 3 is driven to return the double-fed document to the mounting table 1. Can be done properly. If such a double feed retry function is not installed, the clutch portion 103 may not be provided.

As described above, in the present embodiment, when the driving force is transmitted from the drive gear unit 101 to the feed gear unit 112 by driving the motor 3, the feed roller shaft 11b is moved in the feed direction together with the feed gear unit 112. Rotate in the direction of the solid arrow D2 in FIG. At this time, the one-way clutch 11a meshes with the feeding roller shaft 11b, so that the feeding roller portion 11 rotates together with the wheel portion 111 in the feeding direction.

Here, the transport speed of the feed roller 110 is set to a speed slower than the transport speed of the transport roller 21, which will be described later. Therefore, when the fed document S reaches the transport roller 21 and the transport speed of the document S increases, the one-way clutch 11a and the feed roller shaft 11b are disengaged, and the feed roller 110 is brought to the transport document S. It rotates and rotates faster than the speed at which it rotates due to drive transmission from the motor 3.

That is, the transport document S that has reached the transport roller 21 receives the transport force from the transport roller 21 in which the speed difference between the feed roller 110 and the feed roller 110 is set large, so that the transport document S is brought into contact with the feed roller 110 and the feed roller 110. It will be pulled out from between the separated roller 12 and the separated roller 12.

At this time, in the present embodiment, as described above, since the one-way clutch 11a is individually provided for the left and right feeding roller portions 11, the conveyed document S reaching the conveying roller 21 is skewed. Even if the one-way clutch 11a is pulled out from between the feeding roller 110 and the separation roller 12, the skew chain of the subsequent document S is suppressed by the operation of the individual independent one-way clutch 11a (hereinafter, “the effect of suppressing the skew chain”). ..

Here, in the feed roller 110 of the present embodiment, as described above, the feed gear section 112 is arranged in the gap between the feed roller sections 11 in the axial direction of the feed roller shaft 11b, so that the feed roller 110 is fed. The driving force of the motor 3 is stably transmitted to the roller 110.

That is, the feeding roller 110 receives an urging force from the separation roller 12, and the drive transmission to the feeding roller shaft 11b is performed between the feeding roller portions 11 against this urging force. Therefore, the drive transmission is performed in a well-balanced manner at substantially even positions in the left and right feeding roller portions 11.

Further, the feed roller 110 of the present embodiment is configured such that the separation roller 12 is in contact with each roller end on the feed gear portion 112 side of each feed roller portion 11.

That is, the separation roller 12 is evenly urged by a spring or the like against each feed roller portion 11 of the feed roller 110, but in the configuration of the present embodiment, the feed gear of each feed roller portion 11 The gear connection between the feed gear portion 112 and the drive gear portion 101 is further stabilized by the configuration in which pressure contact is made with each roller end portion on the portion 112 side. As a result, power transmission to the feeding roller 110 can be performed more stably, and a good balance between the left and right sides of the contact pressure with the separating roller 12 can be maintained.

In the present embodiment, as described above, the separation rollers 12 are contacted at each roller end on the feed gear portion 112 side (opposite side of each other) of the feed roller portions 11. , The roller end on the side opposite to the feed gear portion 112 side may be in contact with the separation roller 12, or the central portion of each feed roller portion 11 in the axial direction is in contact with the separation roller 12. You may. In any case, it is preferable that the separation roller 12 is evenly pressed on the left and right sides of each feeding roller portion 11.

In this way, the feeding roller portion 11 of the present embodiment receives the urging force of the separation roller 12 and is brought into contact with the separation roller 12 in a well-balanced manner on the left and right sides. That is, the posture of the feeding roller 110 with respect to the separating roller 12 is stable. Therefore, since the left and right nip forces are evenly applied to the document S, skewing of the document S can be prevented and stable feeding operation can be performed for various types of documents. .. Further, even if the preceding document S is skewed, the individual operation of the one-way clutch 11a described above can be stably executed with respect to the succeeding document S, so that the effect of suppressing the skew chain can be further enhanced.

Further, in the present embodiment, the feed gear portion 112 is provided with a cylindrical portion for holding the feed roller shaft 11b, and the tubular portion 112a projects on both sides of the feed roller shaft 11b in the axial direction and extends. Has been done. As a result, the wheel portion 111 or the one-way clutch 11a holding each feeding roller portion 11 and the end portions (first and second contact portions) of the cylindrical portions 112a come into contact with each other, so that each feeding roller portion 11 The interval between the two can be kept constant. However, the tubular portion 112a of the feed gear portion 112 and the wheel portion 111 or the one-way clutch 11a do not have to be in constant contact with each other, and the wheel portion 111 can move slightly in the axial direction with respect to the feed roller shaft 11b. The wheel portion 111 may be configured so as to be able to come into contact with the feed gear portion 112 when the wheel portion 111 is moved to the feed gear portion 112 side together with the one-way clutch 11a. In any case, the cylindrical portion 112a of the feed gear portion 112 can keep the distance between the feed roller portions 11 constant.

That is, the feeding gear section 112 of the present embodiment serves to regulate the interval between the feeding roller sections 11. Although it has been described here that the wheel portion 111 and the end portion of each cylindrical portion 112a of the feed gear portion 112 are in contact with each other, the same effect can be obtained even if the wheel portion 111 is brought into contact with the side surface portion of the one-way clutch 11a. Be done.

Further, by substantially covering the one-way clutch 11a with each cylindrical portion 112a of the feed gear portion 112 as in the present embodiment, it is possible to prevent paper dust and the like from entering the gap of the one-way clutch 11a. The effect can also be expected.

The feeding roller 110 and the separation roller 12 described later are each one unit, and are removable units from the device. Therefore, maintenance is easy, and the unit of the feeding roller 110 can be replaced when the roller surface is worn.

<Separation part>
The separation roller 12 arranged to face the feed roller 110 described above is a roller for separating the documents S one by one, and is in pressure contact with the feed roller 110 at a constant pressure. In order to secure this pressure contact state, the separation roller 12 is supported by the separation swing member 121 as shown in FIG. The separation swing member 121 is rotatably supported around the shaft portion 121a, and an urging force is applied by a compression spring 122 so that the separation roller 12 is in pressure contact with the feeding roller 110.

As shown in FIG. 1, the separation roller 12 is rotationally driven in the direction of the solid arrow D3 by transmitting a driving force from the motor 3 via the torque limiter 12a. Since the transmission of the driving force of the separation roller 12 is regulated by the torque limiter 12a, the separation roller 12 rotates in the direction (in the direction of the broken arrow D4) around the feeding roller 110 when it is in contact with the feeding roller 110. As a result, as shown in FIG. 6, when a plurality of documents S are conveyed to the nip portion (pressure contact portion) N between the feeding roller 110 and the separation roller 12, two or more documents S are left. The document S is dammed so that it is not transported downstream.

Such a portion where the feeding roller 110 and the separating roller 12 are brought into contact with each other and exert a separating action on the document, that is, a portion for handling the document functions at least as a separation feeding section. The "feeding section" is formed by the left and right feeding roller sections 11 and the separation roller 12, for example, when the feeding roller 110 is composed of two feeding roller sections 11 as in the present embodiment. It has a meaning as a separate feeding unit including a portion (gap) sandwiched between the nip portions N, that is, between the feeding roller portions 11. Therefore, the downstream region of the separate feeding unit in the feeding direction includes a region extending downstream from the gap of each feeding roller unit 11.

Although the structure using the separation roller 12 has been described in the present embodiment, the structure is not necessarily limited to the roller form, and a load is applied to the document S in the direction opposite to the feeding direction, for example, a separation pad or the like. The same applies to the case where the above is used, and any form of the separating member may be used.

<Original detection structure of the feeder>
As shown in FIG. 1, a document detection sensor 90 is provided upstream of the feeding roller 110 in order to detect the presence or absence of the document S on the mounting table 1. The document detection sensor 90 is a lever-type sensor provided so as to hang down from the upper side to the lower side in the vertical direction by its own weight. As another example, optical sensors such as the medium detection sensors 50 and 60 described later may be used.

Here, in the present embodiment, the document detection sensor 90 is a sensor that detects the presence or absence of a document immediately before the nip portion formed by the separation roller 12 and the feed roller portion 11 in the feed direction. Therefore, the document detection sensor 90 is preferably arranged between the left and right feeding roller portions 11 which are located near the nip portion, and in that case, the document detection sensor 90 feeds with the cover member a3 sandwiched between them. It will be provided at a portion of the roller 110 facing the feed gear portion 112.

For example, when setting the outer diameter of the feed gear unit 112 in transmitting the driving force, it is preferable to prevent physical interference with the document detection sensor 90 (and the cover member a3), but the document detection In some cases, it may be desired to move the document detection position closer to the nip in order to improve accuracy.

Therefore, in order to achieve both of them, the feeding roller section overlaps the feeding roller section 11 and the feeding gear section 112 in the axial direction of the feeding roller section 11. It is preferable to extend each of the 11 and the feed gear portion 112 in a fang shape.

Even in this case, it is preferable that the cover member a3 is interposed between the document detection sensor 90 and the feed gear portion 112. In that case, the central portion of the cover member a3 protrudes toward the separation roller 12 in order to prevent interference with the feed gear portion 112, and both sides of the central portion feed in order to prevent interference with the document detection sensor 90. It is preferable that the shape protrudes toward the roller shaft 11b.

As a result, the cover member a3 covers the periphery of the feeding roller 110 including the feeding gear portion 112 to prevent paper dust and the like from adhering to the driving system, and the driving portion of the feeding roller 110 and the driving portion of the feeding roller 110. On the surface of the cover member a3, the document detection portion that detects the presence or absence of the document by the document detection sensor 90 can be structurally separated from the document detection portion.

It is preferable that the fang-shaped tip portions of the document detection sensor 90 are connected to each other in order to secure the rigidity of the document detection sensor 90, and in that case, the connection portion is connected to the feed gear portion 112. It is preferable to form the shape so as to bypass the downstream side in the feeding direction. As a result, while ensuring the rigidity of the document detection sensor 90, the document detection position can be brought closer to the nip portion, and the degree of freedom in designing the feed gear portion 112 can be further increased.

By adopting the lever-type document detection sensor 90 as in the present embodiment, a space for providing the feed gear portion 112 in the feed roller 110 is secured, and in addition to highly accurate document detection, left and right contact is even. Good separate feeding can be performed under pressure.

<Pick arm / Original stopper>
As shown in FIG. 1, the document feeding device A includes a pick roller 131 that presses the document S against the feeding roller 110 on the upstream side of the nip portion (press contact portion) where the feeding roller 110 and the separation roller 12 are in contact with each other, and a pick roller. A pick arm 13 that pivotally supports 131 is provided. The pick roller 131 presses the document S against the feeding roller 110 to increase the transporting force of the document S and assists in feeding the document S.

The pick arm 13 has a shaft portion 13a of the pick arm 13 rotatably supported by the device A, and is urged by a spring (not shown) in a direction of pressing the pick roller 131 against the feeding roller 110. The pick arm 13 will be described later in a pressure contact position where the pick roller 131 shown in FIG. 1 presses the document S against the feeding roller 110 and a retracting position where the pick roller 131 shown in FIG. 2 is retracted from the feeding roller 110. It can be moved by the driving force of the motor 4.

As another configuration for assisting the feeding of the feeding roller 110, there is also a configuration in which another feeding roller is provided upstream of the feeding roller 110, but in the configuration of FIG. 1 above, the device can be downsized or the device can be installed. Cost reduction can be realized.

The document feeding device A includes a document stopper 14 as shown in FIG. The document stopper 14 has a role of damming the loaded document bundle by projecting its tip toward the transport path side in the state of FIG.

The document stopper 14 has an opening position in which a shaft portion 14a of the document stopper 14 is rotatably supported by the device A to open a transport path so that the document S shown in FIG. 1 can be fed, and a feeding position shown in FIG. It can be moved to the closing position where the transport path is closed so that the bundle of documents does not enter the nip. FIG. 2 shows a standby state of the document feeding device A, and in this state, the tip of the document bundle can be abutted against the document stopper 14 to set the document bundle on the mounting table 1.

The motor 4 is connected via a pulley P and a belt 4a on one end side of a transport roller shaft 21a that holds the transport roller 21 and a transport roller shaft 31a that holds the transport roller 31.

That is, the motor 4 is a drive source for driving the transport rollers 21 and 31, and is provided as a motor different from the motor 3 for driving the feed rollers described above. As a result, if the motors 3 and 4 are individually controlled, highly accurate feed / transport control can be realized by separately controlling the feed / feed drive and the transport drive.

The pick arm 13 and the document stopper 14 are driven by a motor 4 that drives the above-described transport rollers 21 and 31 via a drive transmission mechanism Y (see FIG. 3). When the motor 4 drives a predetermined number of pulses in the forward direction, the pick arm 13 moves to the pressure contact position, the document stopper 14 moves to the opening position, and the motor 4 drives the predetermined number of pulses in the opposite direction, whereby the pick arm 13 Moves to the retracted position and the document stopper 14 moves to the closed position. Here, the positive direction is a direction in which the transport rollers 21 and 31 described later are rotated so as to transport the document S in the feed direction D1 in FIG.

<Transport structure>
As shown in FIG. 1, the second transport unit 20 as a transport mechanism on the downstream side of the first transport unit 10 in the feed direction includes a transport roller 21 and a driven roller 22 that follows the transport roller 21. 1 The document S transported from the transport unit 10 is transported to the downstream side thereof. The driving force is transmitted from the motor 4 to the transfer roller 21, and the transfer roller 21 is rotationally driven in the direction of the solid line arrow in the figure. The driven roller 22 is pressed against the transport roller 21 at a constant pressure and is brought around to the transport roller 21.

The third transport unit 30 located downstream of the second transport unit 20 in the feeding direction includes a transport roller 31 and a driven roller 32 driven by the transport roller 31, and is transported from the second transport unit 20. The original document S that has arrived is conveyed to the discharge tray 2. That is, the third transport unit 30 functions as a discharge mechanism. The driving force is transmitted from the motor 4 to the transfer roller 31, and the transfer roller 31 is rotationally driven in the direction of the solid line arrow in the figure. The driven roller 32 is pressed against the transport roller 31 at a constant pressure and is brought to the transport roller 31.

<Double feed detection>
As shown in FIGS. 1 and 2, in the double feed detection sensor 40 arranged between the first transport unit 10 and the second transport unit 20, the documents S such as paper are brought into close contact with each other due to static electricity or the like, and the first This is an example of a detection sensor (a sensor that detects the behavior and state of the document S) for detecting when the paper has passed through the transport unit 10 (that is, in the case of a double feed state in which the paper is transported in an overlapping manner).

Various types of double feed detection sensors 40 can be used, but in the case of the present embodiment, they are ultrasonic sensors, which include an ultrasonic wave transmitting unit 41 and an ultrasonic wave receiving unit 42, and a manuscript S such as paper. The double feed is detected on the principle that the amount of attenuation of the ultrasonic waves passing through the document S is different between the case where the ultrasonic waves are double-fed and the case where the ultrasonic waves are conveyed one by one.

In such a double feed detection sensor 40, a double feed detection region 40a is formed at a portion sandwiched between the ultrasonic wave transmitting unit 41 and the ultrasonic wave receiving unit 42 (see FIG. 5). Since sonic vibration is generated in this double feed detection region 40a, even if paper dust is mixed there, it is conceivable that the paper dust is scattered to other parts by the sonic vibration to prevent the paper dust from remaining. As a result, the amount of ultrasonic wave attenuation fluctuates, and the accuracy of double feed detection may deteriorate.

In the present embodiment, as shown in FIG. 5, a downstream portion extending downstream of the document feeding direction (specifically, a portion composed of the feeding roller 110 and the separating roller 12) of the document. _{Of the area Z, the downstream area Z 2} excluding the downstream area _{(paper dust area Z 1} ) extending downstream in the document feeding direction from the nip portion between the feeding roller 110 and the separation roller 12 is targeted. It is preferable to provide the double feed detection region 40a. The double feed detection region 40a is _{preferably provided in the downstream region Z 2} as described above, but a part or all of the double feed detection region 40a may be arranged so as to be included in the _{paper dust region Z 1.}

For example, in the present embodiment, the ultrasonic wave transmitting section 41 and the receiving section 42 move up and down toward the _{downstream region Z 2} extending downstream from the gap between the feeding roller sections 11 of the feeding roller 110 in the document feeding direction. The double feed detection region 40a is set by arranging them so as to face each other so as to sandwich the route (transport path) RT. As a result, the double feed detection region 40a is _{set at a position outside the paper dust region Z 1,} so that the influence of paper dust can be reduced and the accuracy of double feed detection can be improved.

Further, in the present embodiment, the double feed detection sensor 40 shows a structure provided at a substantially intermediate point between the feed roller 110 and the transport roller 21 in the document feed / transport direction in FIG. 5, for example. It is preferable that the feeding roller 110 and the separating roller 12 are arranged close to the pressure-contacted nip portion N. That is, it is preferable that the double feed detection sensor 40 is provided on the upstream side of the intermediate point between the feed roller 110 and the transport roller 21. As a result, the double feed detection can be performed earlier, and the closer to the gap between the feed roller portions 11, the smaller the influence of the paper dust, which contributes to the improvement of the accuracy of the double feed detection.

<Movement detection unit>
Although not shown, the movement detection sensor 45 includes, for example, a light source that irradiates light toward a transport path, and an imaging unit that receives light emitted from the light source and reflected from a document to take an image (photograph). The movement detection sensor 45 of the present embodiment is, for example, a sensor completed in one package, in which light is emitted from a light source to a document in one detection area, and the reflected light from the document is received by an imaging unit. This is a tracking type sensor that acquires the obtained image at a predetermined sampling cycle, tracks the movement of feature points included in the image, and detects the movement amount or movement direction of the document based on the result.

That is, the movement detection sensor 45 of the present embodiment is a tracking sensor that tracks the movement or change of feature points in a sheet image of a document taken in one detection area, and is mainly a document in a transport path. It is used as a sensor to detect diagonal movement (skew). Then, as shown in FIG. 5, the movement detection region 45a of such a movement detection sensor 45 is relatively smaller than, for example, the double feed detection region 40a of the double feed detection sensor 40, for example, from a 1 mm square region. In this case, it is more susceptible to paper dust than the double feed detection sensor 40. In the present embodiment, the movement detection sensor 45 and the double feed detection sensor 40 form a sheet detection unit, but sensors other than these may be additionally arranged at the same positions.

Therefore, in the present embodiment, the above-mentioned movement detection sensor 45 extends to the transport surface of the path RT on the side where the feed roller 110 is provided, on the downstream side in the feed direction of the document from the separate feed section of the document. It is provided corresponding to the _{downstream region Z 2} of the downstream region Z excluding the paper dust region Z _1. As a result, the movement detection region is _{set at a position outside the paper dust region Z 1,} so that the influence of paper dust can be reduced and the accuracy of movement detection can be improved.

Further, in the present embodiment, as shown in FIG. 5, the movement detection sensor is provided on the upstream side of the path RT of the double feed detection sensor 40 in relation to the double feed detection sensor 40. This is because even if paper dust is mixed in the double feed detection region 40a of the double feed detection sensor 40 and the paper dust is scattered to the outside by ultrasonic vibration, the movement detection sensor 45 is upstream of the double feed detection sensor 40. By arranging it on the side, it is possible to prevent the influence on the movement detection sensor 45 in advance.

Further, in the present embodiment, the one-way clutch portion 11a is provided in each feeding roller portion 11 to suppress the oblique chain, and the drive transmission to the feeding roller 110 is provided in the gap of each feeding roller portion 11. Since it is performed by the feed gear unit 112, it is possible to suppress the occurrence of skewing. However, for example, when a plurality of originals are bound on one side of a corner of the original by staples, the bound portion becomes the center of rotation of the original and the original is skewed, and the separate feeding operation is continued as it is. If this happens, the original may be damaged. Therefore, such skewing of the bound document can be detected by the movement detection sensor 45, and the drive of the separation feeding unit can be temporarily stopped at an early stage based on the detection result.

<Resist sensor>
The medium detection sensor 50 arranged on the downstream side in the feeding direction from the double feed detection sensor 40 described above is on the upstream side of the second transport unit 20 and on the upstream side arranged on the downstream side of the first transport unit 10. This is an example as a detection sensor (sensor for detecting the behavior and state of the document S), and the position of the document S transported by the first transport unit 10, specifically, the edge of the document S at the detection position of the medium detection sensor 50. Detects whether the part has reached or passed. In the present embodiment, as shown in FIGS. 1, 2, and 5, the medium detection sensor 50 is further on the second transport unit 20 side with respect to the double feed detection sensor 40 and the movement detection sensor 45 described above. in is provided in the same downstream region Z _2.

Various media detection sensors 50 can be used, but in the case of the present embodiment, the medium detection sensor 50 is an optical sensor, includes a light emitting unit 51 and a light receiving unit 52 thereof, and has a light receiving intensity upon arrival or passage of the document S. The document S is detected on the principle that the (light receiving amount) changes.

In the case of the present embodiment, when the tip of the document S is detected by the medium detection sensor 50, the above-mentioned medium detection is performed so that the document S has reached a position where double feed can be detected by the double feed detection sensor 40. The sensor 50 is provided on the downstream side of the double feed detection sensor 40 in the vicinity of the sensor 50. The medium detection sensor 50 is not limited to the above optical sensor, and for example, a sensor (image sensor or the like) capable of detecting the end of the document S may be used, or a lever-type sensor protruding from the path RT. It may be.

A medium detection sensor 60 different from the medium detection sensor 50 is arranged on the upstream side of the image reading unit 70. This is an example of a detection sensor on the downstream side arranged on the downstream side of the second transport unit 20, and detects the position of the document S transported by the second transport unit 20.

Various media detection sensors 60 can be used, but in the case of the present embodiment, the medium detection sensor 60 is an optical sensor similar to the medium detection sensor 50, includes a light emitting unit 61 and a light receiving unit 62, and reaches the document S. Alternatively, the document S is detected on the principle that the light receiving intensity (light receiving amount) changes depending on the passage.

<Arrangement of CIS>
The image reading unit 70 located on the downstream side of the medium detection sensor 60 is, for example, optically scanned, converted into an electric signal, and read as image data, and has a light source such as an LED, an image sensor, and a lens array inside. Etc. are provided. In the case of the present embodiment, one image reading unit 70 is arranged on each side of the path RT, and is composed of a contact image sensor (CIS) that reads the front and back surfaces of the document S.

<Explanation of block diagram>
The control unit 80 will be described with reference to FIG. FIG. 6 is a block diagram of the control unit 80 of the document feeding device A.

The control unit 80 includes a CPU 81, a storage unit 82, an operation unit 83, a communication unit 84, and an interface unit 85. The CPU 81 controls the entire document feeding device A by executing the program stored in the storage unit 82. The storage unit 82 is composed of, for example, a RAM, a ROM, or the like. The operation unit 83 is composed of, for example, a switch, a touch panel, or the like, and receives an operation from an operator.

The communication unit 84 is an interface for performing information communication with an external device. When a PC (personal computer) is assumed as the external device, the communication unit 84 may include, for example, a USB interface or a SCSI interface. Further, in addition to such a wired communication interface, the communication unit 84 may be used as a wireless communication interface, and may include both wired communication and wireless communication interfaces.

The interface unit 85 is an I / O interface that inputs / outputs data to / from the actuator 86 and the sensor 87. The actuator 86 includes a motor 3, a motor 4, and the like. The sensor 87 includes a double feed detection sensor 40, a movement detection sensor 45, medium detection sensors 50 and 60, an image reading unit 70, a document detection sensor 90, and the like.

<Drive by receiving start instruction from PC>
The basic operation of the document feeding device A will be described. When the control unit 80 receives, for example, an image reading start instruction from an external personal computer to which the document feeding device A is connected, the control unit 80 starts driving the first to third transport units 10 to 30. The manuscripts S loaded on the mounting table 1 are conveyed one by one from the manuscript S located at the bottom thereof. The image reading start instruction may be executed by pressing the start button provided on the document feeding device A.

<Start reading according to the output of the resist sensor>
The control unit 80 starts reading the image of the document S transported by the second transport unit 20 by the image reading units 70 and 70 at the timing based on the detection result of the medium detection sensor 60, and first reads the scanned image. It is memorized and sent to an external personal computer in sequence. The document S from which the image has been read is discharged to the discharge tray 2 by the third transport unit 30, and the image scanning process of the document S is completed.

<Operation flow of feeding / transporting>
Next, the operation flow of feeding / transporting will be described with reference to FIG. 7.

In step S1, the control unit 80 receives, for example, an image reading start instruction from an external personal computer to which the document feeding device A is connected.

In step S2, the control unit 80 determines the presence or absence of the document S on the mounting table 1 by the document detection sensor 90.

In step S3, when the control unit 80 determines that the document S does not exist by the document detection sensor 90, a cautionary note indicating that the document S does not exist is displayed on an external personal computer or the like, and the process ends without feeding or transporting.

In step S4, when the control unit 80 determines that the document S is on the mounting table 1 by the document detection sensor 90, the control unit 80 drives the motor 4 in the forward direction. At this time, the pick arm 13 is moved to the pressure contact position, and the document stopper 14 is moved to the opening position.

In step S5, the control unit 80 drives the motor 3 to rotate the feeding roller 110 in the direction (forward direction) of feeding the document S to feed the document S.

In step S6, it is detected that the tip of the conveyed document S has passed through the medium detection sensor 50, and then in step S7, it is detected that the tip of the conveyed document S has passed through the medium detection sensor 60.

At this time, since the tip of the conveyed document S has passed through the medium detection sensor 60, the conveyed document S has reached the second conveying section 20, so that even if the first conveying section 10 is stopped, the conveyed document S remains. Since the motor 3 is transported by the second transport unit 20, the control unit 80 stops the motor 3 in step S8.

On the other hand, the image reading of the document S is started after a predetermined time of reaching the image reading unit 70 has elapsed from the time when the tip of the document S reaches the medium detection sensor 60.

In step S9, it is detected that the rear end of the conveyed document S has passed through the medium detection sensor 60. After a predetermined time has elapsed from this time, the image scanning of the original S is completed. As a result, a series of scanning operations for one document S is completed.

In step S10, the control unit 80 determines the presence or absence of the document S on the mounting table 1 by the document detection sensor 90. If it is determined that the document S is present, the process proceeds to step S5, and the document S is conveyed and the image is read.

If the document detection sensor 90 determines in step S10 that there is no document S on the mounting table 1, the control unit 80 stops the motor 4 in step S11. At this time, the motor 4 is stopped after a lapse of a predetermined time so that the document that has passed through the medium detection sensor 60 is discharged by the third transport unit 30. If the motor 4 does not drive the third transport unit, the motor 4 may be stopped immediately.

After that, in step S12, the control unit 80 drives the motor 4 in the opposite direction by a predetermined number of pulses and then stops. At this time, the pick arm 13 is moved to the retracted position and the document stopper 14 is moved to the closed position to stop. This completes the feeding / transporting operation.

Based on the above operation flow, transport control for feeding the next document S is performed using the medium detection sensor 60 as a trigger. As a result, a predetermined space is provided at the reading position of the image reading unit 70, so that the document S can be stably conveyed continuously.

<Separation rocking member>
As shown in FIG. 8, the separation swing member 121 is provided on the side portion of the separation roller 12, and is swingably supported by the rib portion 121b provided with a surface that abuts on the document S and the rib portion 121b. It has a limiting member 1211 and a spring 1212 that urges the limiting member 1211. The limiting member 1211 is an example of a movable member, and enters the space between the separation roller 12 and the tip end side of the document as described later.

As shown in FIG. 8 which is a side view of the separation rocking member 121, the rib portion 121b has a surface 121c which is substantially the same surface as the outer surface on the upstream side in the feeding direction with respect to the rotation center of the separation roller 12. When a heavy document bundle such as a stack of documents with a large number of loaded sheets is fed, the tip of the document bundle abuts on the surface 121c, so that the upper document S in the loaded document bundle is pressed by the separation roller 12 and the separation roller 12 is pressed. It prevents the surface on the upstream side of 12 from being crushed, limits the number of document bundles that can enter the feeding nip, and reduces feeding defects.

The limiting member 1211 is provided so as to protrude toward the transport path from the projecting portion 121d, which is the protruding tip of the rib portion 121b toward the transport path side, and also project from the rib portion 121b to the upstream side in the feeding direction. The limiting member 1211 is rotatable about the shaft portion 1211a, is urged by the spring 1212 in the direction of projecting into the transport path (direction of arrow D5 in the figure), and the rotation stopping portion 1211b abuts on the rib portion 121b.

The limiting member 1211 is urged by a spring 1212 so as to retract (rotate in the direction opposite to the arrow D5) when a heavy document bundle is set and not to retract when a light document bundle is set. .. A light document bundle is a document such as a bundle of slips, which is particularly thin and has a small document size.

For example, in the present embodiment, in the document feeding device A having a maximum load of 60 sheets, the transport path is 40 degrees with respect to the installation surface of the document feeding device A, and in this case, the basis weight is 80 g. When 60 sheets of A4 size OA paper are set at / m ² , the limiting member 1211 is pushed by the document bundle and retracted, and when 60 sheets of A6 size slips are set at a ^{basis weight of 40 g / m 2, the limiting member 1211} The load of the spring 1212 is set so that the paper is not retracted even if it is pushed by the document bundle.

In this way, the urging force of the spring 1212 that urges the limiting member 1211 can be set to the specifications of the document feeding device A and to what extent the document bundle is retracted, and is not necessarily unique. It is not decided by.

By providing such a limiting member 1211, it is possible to prevent a feeding jam (paper jam) of thin paper in particular. When the limiting member 1211 is not provided, as shown in FIG. 9, when feeding a thin document bundle such as a slip, a part of the document bundle enters the feeding nip and is between the feeding nip and the tip of the document bundle. Space K may be created in.

At this time, while the document S1 is being fed, the document S2 to be fed next in the space K is hung and receives a force in the feeding direction (positive direction), and also receives a force in the negative direction from the separation roller 12. The tip of the document S2 may be bent, and the tip of the document S2 may be turned over or jammed.

On the other hand, in the present embodiment, by providing the above-mentioned limiting member 1211, as shown in FIG. 10, the amount of the document bundle entering the feeding nip is limited for the thin document bundle such as a slip. The space K between the feeding nip and the tip of the document bundle can be reduced to suppress the deflection of the document S2 in the space K, and the tip of the document S2 can be turned over or jam can be suppressed.

Since the limiting member 1211 retracts from the heavy document bundle, the contact area between the document S and the feeding roller 110 does not change and the conveying force does not decrease, so that the document S does not fail to feed. Further, since the thick manuscript S such as a credit card also receives the conveying force of the feeding roller 110 and the manuscript S pushes the limiting member 1211 to retract the manuscript S, non-feeding of the manuscript S does not occur.

Since the limiting member 1211 is provided so that the document S is in sliding contact with the separation roller 12 on both the left and right sides of the separation feeding portion, not a little paper dust is generated even in the sliding contact portion. There is a risk. In the present embodiment, as described above, the double feed detection sensor 40 and the movement detection sensor 45 are _{provided in the downstream region Z 2} extending downstream from the gap of each feed roller portion 11, so that the sensors 40 and 45 are provided. , The influence of paper dust generated by sliding contact of the limiting member 1211 can be effectively avoided.

Further, as shown in FIG. 8, a document detection sensor 90 for detecting the arrival of the document S is provided at a position between the plurality of feeding rollers 110. The document detection sensor 90 is pivotally supported by the detection sensor shaft 90a and hangs by its own weight. In order to make it possible to retract the detection sensor shaft 90a around the detection sensor shaft 90a regardless of the type of the document S that arrives, it is configured to be as light as possible and to have almost no resistance due to friction or the like against the rotational movement.

A feeding roller guide 17 is provided on the upstream side of the document detection sensor 90. The feeding roller guide 17 is pivotally supported by a guide shaft 17a provided on the upstream side of the feeding roller 110, and extends toward the downstream side in the feeding direction.

The feeding roller guide 17 is arranged in a direction orthogonal to the feeding direction (thickness direction of the conveyed document) so that the tip of the feeding roller guide 17 moves from the feeding roller 110 side to the separation roller 12 side by the guide urging means 17b shown in FIG. When the document S is urged and does not exist on the mounting table 1, the tip of the document S protrudes from the outer periphery of the feeding roller 110 when viewed from the axial direction (direction shown in FIG. 13) of the feeding roller 110. It is positioned by an abutting portion (not shown) in a state of being urged to the position.

When a plurality of documents S are placed on the mounting table 1 by the feeding roller guide 17, the feeding roller guide 17 is moved to the feeding roller 110 side against the urging means as shown in FIG. Be urged. Further, when the number of manuscripts S is small, particularly when only one thin paper manuscript S is placed on the mounting table 1, or when the number of manuscripts S to be placed is small, as shown in FIG. The original is urged toward the separation roller 12 by the roller guide 17.

Then, while the tip of the document S is in sliding contact with the feeding roller guide 17, the document S is prevented from coming into contact with the feeding roller 110. With this configuration, when the document S is set on the mounting table 1, it is possible to prevent the document S from being caught by the feeding roller 110 and being unable to be set at a predetermined setting position when the document S is small.

In this embodiment, as shown in FIG. 8, the tip of the separation roller 12 side (downstream side in the feeding direction) of the feeding roller guide 17 is located between both sides of the feeding roller 110 and the feeding roller 110. Since the feeding roller guide 17 is provided so as to be arranged, the tip of the document S may come into contact with the feeding roller 110 when the bundle of documents on the mounting table 1 becomes small. It can be surely prevented.

Further, the feed roller guide 17 can locally lift the document S to make the document S stiff. According to the feeding roller guide 17 in the present embodiment, the plurality of feeding roller guides 17 are urged in the direction of lifting the document S on the upstream side of the feeding roller 110, and are fed in a state of being stiffened. The document S can be inserted into the nip between the roller 110 and the separation roller 12.

In addition, since the amount of the original S that the limiting member 1211 abuts and rushes into the nip can be limited for the original S that is still weak, it is effective to turn over the tip of the original S and cause a paper jam. Can be suppressed. Here, in the present embodiment, the turning of the tip of the document includes a state in which the document is fed with wrinkles as a result of turning.

In this embodiment, the cover member a3 shown in FIG. 4 is provided so as to cover the feeding roller 110 and the feeding roller guide 17. The guide shaft 17a and the guide urging means 17b of the feeding roller guide 17 are attached to the side of the cover member a3 of the feeding roller 110 opposite to the surface on which the document slides (lower side in FIG. 7), and the cover. The member a3 and the feeding roller guide 17 form an integrated unit.

By removing the cover member a3 of the feeding roller 110, the shaft and bearings of the feeding roller 110 are exposed, and the feeding roller 110 can be attached to and detached from the document feeding device A. The cover member a3 of the feeding roller 110 is provided with a concave storage portion at a position where the tip of the document stopper 14 is stored.

In the present embodiment, since the limiting member 1211 is supported by the separation swing member 121, deterioration of the feeding performance can be suppressed even when the feeding roller 110 and the separating roller 12 are worn.

In the configuration in which the limiting member 1211 is supported on the fixed component 15 that does not swing instead of the separating swinging member 121 as shown in FIG. 14A, the separating roller 12 is supplied when the feeding roller 110 and the separating roller 12 are worn. Since it is pressed against the feed roller 110 side, the pitch m between the axes of the feed roller 110 and the separation roller 12 is shortened as shown in FIG. 14B, and the gap n'between the limiting member 1211 and the feed roller 110 is the gap n. Since the space K in FIG. 11 becomes large at the time of feeding, the effect of reducing the turning of the tip of the document and the paper jam becomes small.

However, if the limiting member 1211 is supported on the swinging separation swing member 121 as shown in FIG. 15A, when the feeding roller 110 and the separation roller 12 are worn, FIG. 15B Even if the inter-axis pitch m of the feeding roller 110 and the separating roller 12 is shortened as described above, the gap n'' between the limiting member 1211 and the feeding roller 110 is smaller than the gap n by the amount of wear of the separating roller 12.

Therefore, since the space K in FIG. 11 does not become large as shown in FIG. 14 (b) at the time of feeding, the problem of feeding such as jam can be suppressed. Actually, the amount of wear of the separation roller 12 is smaller than the amount of wear of the feeding roller 110, and the gap n ″ is not too narrow to prevent feeding.

As shown in FIG. 16, the rib portion 121b and the limiting member 1211 in the present embodiment are arranged on the opposite side of the friction member 11c of the feeding roller 110. The friction member 11c is made of a material such as rubber and is formed on the outer periphery of the roller of the feeding roller 110 so that the document S can be easily gripped.

The feeding roller 110 has two friction members 11c, and rib portions 121b and limiting members 1211 are arranged on both sides of the two separating rollers 12. By making the rib portion 121b and the limiting member 1211 face the friction member 11c, the document S is sandwiched between the rib portion 121b and the limiting member 1211 and the friction member 11c, and the frictional force of the friction member 11c increases. The carrying force is increased and the non-feeding of the document S is prevented.

In other words, the feeding roller 110 is provided with the narrow separation roller 12, and the feeding roller 110 is provided with the limiting member 1211 using the space of the portion where the separation roller 12 is not arranged. By doing so, the limiting member 1211 can be arranged while securing the required width of the separation roller 12 with respect to the width of the feeding roller 110. In particular, as in the present embodiment, the transport path is in the vertical direction. It is effective for miniaturization of a standing relatively small document feeder.

The arrangement of the rib portion 121b and the limiting member 1211 is not limited to this. As shown in FIG. 17, the rib portion 121b and the limiting member 1211 may be arranged between the two separation rollers 12.

Even if the document S is arranged in this way, the document S is sandwiched between the rib portion 121b and the limiting member 1211 and the friction member 11c, and the frictional force of the friction member 11c increases, so that the document S is conveyed. The force is increased and the non-feeding of the document S can be preferably prevented.

Further, as shown in FIGS. 18 and 19, the rib portion 121b and the limiting member 1211 may be arranged at a position not facing the friction member 11c, that is, a position shifted in the thrust direction of the feeding roller 110.

The rib portion 121b and the limiting member 1211 are arranged between the two friction members 11c in FIG. 18, and are arranged on both sides of the two friction members 11c in FIG. When arranged in this way, since it does not face the feeding roller 110, the action of sandwiching the document S between the limiting member 1211 and the friction member 11c is reduced, but the document S is substantially sandwiched and the frictional force can be improved, which limits the effect. The action of pressing the light document bundle by the member 1211 without retracting can be exerted, and the feeding performance can be improved.

FIG. 20 is a cross-sectional view for explaining the arrangement of the rib portion 121b and the limiting member 1211. As shown in FIG. 20B, the rib portion 121b and the limiting member 1211 are arranged on the opposite side of the friction member 11c and near the feeding nip.

As a result, the distance exposed to the transport path of the outer diameter of the feeding roller 110 (from the point a upstream of the outer diameter of the roller to the opposite point b of the protrusion 121d) becomes longer, and the area of the feeding roller 110 with which the document bundle comes into contact. Can be increased to increase the carrying capacity.

Specifically, by arranging the rib portion 121b and the limiting member 1211 on both sides of the separation roller as shown in FIG. 16, it can be arranged on the opposite side of the friction member 11c and near the feeding nip, and the conveying force is strong. can do.

More specifically, as shown in FIG. 20B, the surface 1211e formed on the feed roller 110 side of the limiting member 1211 is the outer peripheral surface of the separation roller 12 and its thrust direction (direction orthogonal to the feed direction). ) Are overlapped and arranged so as to form the same outer surface. By doing so, it is possible to suppress floating or the like by the limiting member 1211 with respect to the document S to be fed, and it is possible to improve the transport performance.

However, the arrangement of the limiting member 1211 is not limited to the above configuration, and in a device or the like in which a heavy document bundle is not conveyed and the feeding force may be small, friction is shown as shown in FIG. 20 (a). The distance exposed to the transport path in the outer diameter of the member 11c (from the point a upstream of the outer diameter of the roller to the opposite point b of the protrusion 121d) may be shortened.

As shown in FIG. 9, the limiting member 1211 has an abutting surface 1211c and an inclined surface 1211d to which the document bundle abuts. The abutting surface 1211c is substantially perpendicular to the feeding direction, and the inclined surface 1211d is a surface inclined in the feeding direction on the feeding roller 110 side of the abutting surface 1211c.

Then, by making the abutting surface 1211c substantially perpendicular to the feeding direction, the upper layer portion of the document bundle is prevented from entering the feeding nip, and the inclined surface 1211d is placed on the feeding roller 110 side of the abutting surface 1211c. By making the surface inclined in the feeding direction, the lower layer portion of the document bundle can easily enter the feeding nip.

Further, in the present embodiment, as shown in FIG. 8, a one-way clutch 11a is provided between the feed roller shaft 11b for rotationally driving the feed roller 110 and each feed roller 110.

That is, when the document S fed by the feeding roller 110 is provided on the downstream side thereof and is about to be pulled out by the transport roller 21 having a peripheral speed faster than that of the feeding roller 110, the feeding roller 110 causes the document S to be pulled out. It is configured so that it can rotate in the direction of rotation.

In that case, as a way of contact between the drive gear (not shown) for transmitting the driving force to the feed gear unit 112 and the feed gear unit 112, the drive gear makes the feed gear unit 112 come into contact with the rotation regulating means described later. The contact state in the driving state will be maintained.

In the case where there is no rotation regulating means, if the document S comes out of the feeding roller 110 in this state, the separating roller 12 that press-contacts the feeding roller 110 may try to push the feeding roller 110 back to the upstream side. .. At this time, the feed roller 110 and the feed gear 112 rotate in the negative direction by the amount of backlash existing between the feed gear portion 112 and the drive gear, and then the document placed on the mounting table 1 is mounted. The tip of S may be returned.

If the tip of the document S is returned in the negative direction, the feeding performance is deteriorated. In order to prevent this, in the present embodiment, for example, as a rotation regulating means, the feeding roller shaft is used. It is preferable to provide an urging means (for example, a compression spring or the like) for determining the position of each feeding roller portion 11 in the axial direction of 11b.

Such an urging means may be provided between the wheel portion 111 and the bearing 110a of the feeding roller shaft 11b, but the feeding gear portion 112 may be provided between the feeding roller portions 11 as in the present embodiment. If it is provided in, it is preferable to provide it between the feeding gear portion 112 and each feeding roller portion 11.

As a result, each of the feeding roller portions 11 is urged toward both ends (bearing 110a side) of the feeding roller shaft 11b in the axial direction of the feeding roller shaft 11b, and the feeding gear portion 112 is urged to the feeding roller shaft. It can be placed in the center of 11b.

Therefore, the drive transmission position from the drive gear shaft 102 is the central portion of the feed roller 110, that is, the central portion in the longitudinal direction of the feed roller shaft 11b, and the load balance of the left and right feed roller portions 11 is stabilized and the feed is supplied. The feed performance can be improved. One of the bearings 110a is substantially U-shaped and is fixed to the apparatus main body A1 so as not to rotate.

With this configuration, it is possible to prevent the document S from being returned in the negative direction, and the feed gear portion 112 is returned by the amount of backlash between the feed gear portion 112 and the drive gear shaft 102, so that the gears collide with each other. It is possible to prevent the generation of tapping sound due to this.

When the urging means is provided in the present embodiment, as described above, it is possible to prevent the generation of tapping sound due to the contact between the gears. When a sound detecting means such as a sensor (microphone) capable of detecting sound is provided in the vicinity of the feed roller 110, a remarkable effect can be obtained in a document feeding device A or the like that detects a jam (paper jam) in the document S. Can improve the accuracy of jam (paper jam) detection.

(Second Embodiment)
The device configuration of the second embodiment is substantially the same as the device configuration of the first embodiment, and the difference is that the limiting member 1211 and the feeding roller 110 are pressed against each other.

As shown in FIG. 21, the limiting member 1211 is pressed against the outer diameter of the feeding roller 110. The limiting member 1211 is rotatable about the shaft portion 1211a, is urged by the spring 1212 in the direction of projecting into the transport path (in the direction of arrow D5 in the figure), and before the rotation stopping portion 1211b abuts on the rib portion 121b. It hits the feeding roller 110.

The contact point between the limiting member 1211 and the feeding roller 110 is upstream of the feeding nip. The limiting member 1211 limits the amount of the document bundle that enters the feeding nip, reduces the space between the feeding nip and the tip of the document bundle, suppresses the deflection of the document S in that space, and causes the tip of the document S to turn over or jam. Can be prevented.

Compared with the first embodiment, in the second embodiment, since there is no gap between the limiting member 1211 and the feeding roller 110, the number of paper bundles entering the feeding nip can be further reduced, and the tip of the document S is turned over or jammed. Can be prevented.

FIG. 22 shows the configuration of the feeding roller 110. The feeding roller 110 has a cylindrical portion 11d having a diameter substantially the same as the outer diameter of the friction member 11c. The cylindrical portion 11d may be a low friction material such as a resin having a lower coefficient of friction than rubber, and rotates integrally with the friction member 11c.

The limiting member 1211 abuts on the cylindrical portion 11d, and when the feeding roller 110 rotates, it slides on the outer diameter of the cylindrical portion 11d. When the tip of the limiting member 1211 is brought into contact with the friction member 11c, the limiting member 1211 is moved by the friction of the friction member 11c due to the rotation of the feeding roller 110, and the feeding performance can be stabilized. It cannot be done, and abnormal noise is likely to occur.

Therefore, for example, it is necessary to provide a structure for reducing friction at the contact position of the limiting member 1211 with the friction member 11c. In the present embodiment, in order to more preferably cause the limiting member 1211 to act on the document S, the limiting member 1211 is configured to come into contact with the cylindrical portion 11d of the low friction material instead of the friction member 11c.

By doing so, the structure of the limiting member 1211 is a cylindrical portion that is a part of the feeding means while having a structure that exerts a suitable action on the document bundle and the document S as described in each of the above embodiments. By abutting against 11d and pressing it against the 11d, it is possible to improve the effect of reducing the tip turning and jam occurrence of the document S.

In the devices of the first and second embodiments, the limiting member 1211 as an example of the movable member is rotatably supported by the separation swing member 121, but the present invention is not limited to this. The movable member may be slidably or swingably supported by the separate swing member 121 so that the limiting member 1211 can be displaced in the thickness direction of the document bundle.

(Third Embodiment)
In the devices of the first and second embodiments, the limiting member 1211 is provided on the separation rocking member 121, but as shown in FIGS. 23 and 24, the elastic member 1213 is provided instead of the limiting member 1211. Even if there is, it has the same effect.

In FIGS. 23 and 24, the elastic member 1213 is an elastically deformable material such as a thin plate or rubber, and is fixed to the separation swing member 121, and one end of the elastic member 1213 is a feeding roller similar to the limiting member 1211. It protrudes to the 110 side.

According to this configuration, similarly to the limiting member 1211 described in the first and second embodiments, the amount of the document bundle that enters the feeding nip for a specific document bundle is limited, and the feeding nip and the document are limited. The space K between the tips of the bundles can be made smaller to suppress the deflection of the document S2 in the space K, and the tip of the document S2 can be turned over and the occurrence of jam can be suppressed.

In the present invention, by arranging the separation roller 12 and the movable member so as to face each other within the width in which the feeding roller 110 is provided (the width in the direction orthogonal to the feeding direction), the feeding roller 110 and the feeding roller 110 are arranged. The action of sandwiching the document with the movable member can be improved, and at the same time, the size can be reduced.

The separation roller 12 can be configured to be smaller in the width direction than the feed roller 110, and a movable member and a separation swing can be utilized by utilizing a portion within the width in which the feed roller 110 is provided where the separation roller 12 is not provided. The member 121 can be arranged.

Here, the range within the width in which the feeding rollers 110 are provided is a region sandwiched between the outer ends of the rollers arranged on the outermost side when a plurality of feeding rollers 110 are provided. .. By arranging both the separation roller 12 and the movable member (and the separation swing member 121) in the space facing the region, the region outside the width in which the feeding roller 110 is provided and the space facing the feed roller 110 are provided. It can be used as a space for arranging other structures.

As described in the above embodiment, the present invention can be suitably used for a device provided with a transport path (feeding direction D1) at a predetermined angle with respect to the mounting surface of the document feeding device A. As an example of the document feeding device A, a scanner used on the desk side is required to be miniaturized, but on the other hand, there is a need to improve the feeding speed. On the other hand, by using the present invention, damage to the original can be reduced and the original can be fed.

In each of the above embodiments, the documents are supplied to the feeding mechanism by the weight of the documents loaded on the mounting table 1 by using the transport path inclined at a predetermined angle with respect to the mounting surface. , The feeding roller 110 is arranged on the lower side of the transport path, and the documents are sequentially fed from the bottom (lowest) of the document bundle loaded on the mounting table 1.

That is, it is possible to feed the original without providing a pick roller or the like for feeding the original, and in the present invention, the second and subsequent originals are brought to the separate feeding mechanism generated in that case. It can be suitably applied to the jam (paper jam) at the tip of the document caused by the entry.

(Third Embodiment)
In the device of the first embodiment, the structure in which the movement detection sensor 45 is provided on the upstream side of the double feed detection sensor 40 in the feeding direction, and the movement detection sensor 45 and the double feed detection sensor 40 are arranged in a row will be described. However, in the present embodiment, as shown in FIGS. 25 (a) and 25 (b), the movement detection sensor 45 is provided in another region.

For example, as shown in FIG. 25 (a), on both sides of the feeding roller shaft 11b of the feeding roller 110 in the axial direction, the parts where the feeding roller portion 11 and the separation roller 12 are not in contact with each other, that is, the nip portion. The movement detection sensor 45 may be provided on one side of _{the downstream region Z 2} on the downstream side in the feeding direction from the portion other than N. As a result, the double feed detection sensor 40 can be arranged close to the nip portion N side, and double feed detection can be detected at an early stage. In this case, the _{movement detection sensors 45 may be provided not only on one side of the downstream region Z 2} but also on the other side, that is, _{on both sides of the downstream region Z 1} so that the movement of the document is tracked and detected on the left and right sides.

Further, as shown in FIG. 25 (b), the nip portion N of the feed roller portion 11 and the separation roller 12 of the feed roller 110A is arranged in the central portion of the feed roller portion 11, and both sides thereof are the feed rollers. When the separate feeding unit is a portion where the pressure 11 and the separation roller 12 are not contacted with each other, a large space for arranging the double feed detection sensor 40 can be provided in the gap between the feeding roller units 11. In this case, as shown in the drawing, a movement detection sensor 45 may be provided on one side of the feeding roller shaft 11 of the feeding roller 110A in the axial direction, as in FIG. 25A. Even in this case _{, the movement detection sensors 45 may be provided not only on one side of the downstream region Z 2} but also on the other side, that is, _{on both sides of the downstream region Z 1} so that the movement of the document is tracked and detected on the left and right sides.

The present invention is, of course, not limited to this, and as shown in FIG. 26, when a portion that does not contact the separation roller 12 is provided on the gap side of each feeding roller portion 11, the gap between the feeding rollers 11 is provided. Can be expanded. Therefore, since the downstream region Z2 on the downstream side can be formed wide from the gap of each feed roller 11, the double feed detection sensor 40 and the movement detection sensor 45 are supplied to the downstream region Z2 as shown in FIG. It may be juxtaposed in the width direction orthogonal to the feeding direction.

Further, when the double feed detection sensor 40 and the movement detection sensor 45 as shown in FIG. 26 are installed, both outer sides of each feed roller portion 11 in the feed roller 110A in the axial direction of the feed roller shaft 11b. The separation roller 12 may be brought into contact with the end of the roller.

(Fourth Embodiment)
In the present embodiment, as shown in FIG. 27, the movement detection sensor 45 may be arranged so as to face the gap between the feeding roller portions 11 of the feeding rollers 110. In this case, since the movement (skew) of the original can be detected immediately after the nip portion N formed by the feeding roller portion 11 and the separation roller 12 and in a place where the influence of paper dust is small, the bound original is separated. In the event of an abnormality such as skewing in feeding, the separate feeding operation can be immediately suspended. Further, if the skew detection described above can be performed before reaching the double feed detection sensor 40, control may be performed to turn off the detection of the double feed detection sensor 40.

In this embodiment, the cover member a3 that covers the feeding roller 110 is arranged. In this case, a window portion (not shown) is provided so as to penetrate the cover member a3, and when the cover member a3 is closed, the window portion of the cover member a3 faces the movement detection sensor 45 on the device main body side. As a result, the movement detection sensor 45 is arranged in the gap between the feeding roller portions 11, and the movement of the document whose posture is relatively stable at the left and right nip portions can be tracked and detected by the movement detection sensor 45 through the window portion. .. In addition, the detection area of the movement detection sensor 45 is less affected by paper dust and enables highly accurate tracking detection, and can also track the movement of the document immediately after the nip portion to prevent feeding abnormalities and the like. Since it can be detected immediately, for example, before the damage to the original occurs, it is possible to take appropriate measures after that, such as pausing the separate feeding operation and error handling.

(Fifth Embodiment)
In each of the above-described embodiments, the configuration in which the feeding gear section 112 is provided between the two feeding roller sections 11 included in the feeding roller 110 has been described. However, in the present embodiment, FIG. 28 shows. As shown, a feeding gear portion 112 that transmits drive to the feeding roller 110 is provided on one end side of the rotating shaft of the feeding roller 110, and the other end of the rotating shaft is rotatably held by a bearing. The feeding roller 110 may be adopted.

For the separate feeding unit composed of the feeding roller 110 and the separating roller 12 as in the present embodiment, the double feeding detection sensor 40 and the movement detection sensor 45 are mounted on paper as in each of the above-described embodiments. The powder region Z ₁ may be removed _{and placed in the downstream region Z 2,} and the same effect can be obtained.

Although this embodiment is a structural example in which one drive motor M drives the feed and transport, the feed and transport may be driven separately by the two motors as in the above-described embodiment.

Further, the feeding roller 110 of the present embodiment may have a configuration in which each feeding roller 11 is individually provided with a one-way clutch portion 11a as in the above-described embodiment, or the feeding roller shaft 11b of each feeding roller 11 may be provided. A feeding roller provided with one one-way clutch portion may be applied to the vehicle.

The present invention is not limited to the embodiments described above, and various modifications can be made without departing from the gist of the present invention.

(Other embodiments)
Although the present invention has been described in detail based on each embodiment, the present invention is not limited to each of the above-described embodiments.

For example, in each of the above-described embodiments, a document transfer device using two motors 3 and 4 has been illustrated, but the present invention is of course not limited to this, and for example, as shown in FIG. 25, a document is driven by one motor. The drive system of the transport device may be controlled.

In the case of a document transport device as shown in FIG. 29, the driving force of a single motor M located on one side in the width direction of the device orthogonal to the document transport direction is transported so as to straddle the transport path. The transfer roller shaft 21a of the roller 21 is used to transmit the device to the drive transmission mechanism X on the other side in the width direction across the transfer path.

As a result, the driving force of a single motor M can be transmitted to the feed roller 110 and the separation roller 12, and the number of parts can be reduced as compared with the configuration using a plurality of motors, resulting in miniaturization or miniaturization. It is possible to realize a document transfer device suitable for cost reduction and weight reduction.

Further, in each of the above-described embodiments, each feeding roller portion 11 has a larger axial width with respect to the separating roller 12, and the separating roller is brought into contact with a part of the feeding roller portion. However, the present invention is, of course, not limited to this, and for example, a separate feeding unit may be provided in which the separating rollers are brought into contact with the entire width of each feeding roller unit in the rotation axis direction of the feeding unit. Even in this case, by arranging the double feed detection sensor and the movement detection sensor in series in the downstream region extending downstream from the gap of each feed roller portion, the influence of paper dust is reduced and the detection accuracy of each is improved. can do.

Further, in each of the above-described embodiments, a structural example in which the feeding roller portion 11 is detachably provided with respect to the wheel portion 111 has been described, but the present invention is of course not limited to this, and for example, the one-way clutch 11a. May be left on the feed roller shaft 11b and removed including the other wheel portions 111.

Alternatively, as shown in FIG. 30, the wheel portion 111 is divided into two in the radial direction, the inner wheel portion (first core portion) 111a is fitted into the one-way clutch portion 11a, and the outer wheel portion (second core portion) 111b is fitted. May be detachably provided with respect to the outer periphery of the inner wheel portion 111a together with the outer wheel portion 111b. In this case, the feeding roller portion 11 and the outer wheel portion 111b are replacement parts.

Further, in each of the above-described embodiments, a structure in which drive transmission to the separation roller 12 is performed from one end side of the axis of the separation roller 12 has been illustrated and described, but the present invention is, of course, not limited to this. For example, the structure of the separation roller as shown in FIG. 31 may be used.

As shown in FIG. 31, when a configuration in which the rollers are divided into two on the left and right in the axial direction is applied as the configuration of the separation rollers 12, a gear portion 12a for drive transmission is provided for the shaft portion 12b between the rollers. As with the feeding roller 110, an improved separation roller 12 to which a drive transmission structure having no left-right balance difference between the rollers may be applied.

For the gear portion 12a of such a separation roller 12, the motor 3 is driven through the gear portions G1 and G2 for power transmission on the other end side of the rotating shaft Ga whose one end is connected to the drive transmission mechanism X. Power is transmitted. Then, both end portions 12c of the shaft portion 12b of the separation roller 12 are rotatably held by bearings (not shown).

With such an improved separation roller 12, the backlash on the left and right sides of each of the feeding roller 110 and the separation roller 12 can be reduced, so that not only the separation feeding performance is further improved, but also the feeding roller 110 is used. If the individual one-way clutch portions 11a are provided in the above, the effect of suppressing the skew chain can be further enhanced.

Further, as described in the above-described embodiment, the separation roller 12 is swingably attached to the separation swing member 121. When the gear portion for driving transmission to the separation roller 12 is on one end side in the axial direction of the separation roller 12, the gear portion becomes a load on the side where the gear portion is provided, which makes it difficult to swing. The other end side tends to swing.

As a result, there is a difference in the left and right swinging motions, and an unbalanced load is generated on the rotation shaft of the separation roller 12. On the other hand, by providing a gear part between each roller, the difference between the left and right swinging motions is reduced, and the pressing force against the feeding roller becomes equal, so that the document is skewed during feeding. It can be suppressed.

When the improved separation roller 12 as described above is adopted, an individual one-way clutch portion 11a is attached to the feeding roller 110 in each of the above-described embodiments, that is, the wheel portion 111 provided with each feeding roller portion 11. It is not necessary to adopt the feeding roller 110 which is not provided and further provides the feeding gear section 112 between the feeding roller sections 11, or the wheel section 111 where each feeding roller section 11 is provided is individually provided. A feeding roller may be adopted in which the one-way clutch portion 11a is provided and the feeding gear portion 112 is not provided between the feeding rollers 110.

Further, when the improved separation roller 12 as described above is adopted, the one-way clutch is not provided in each feeding roller section of the feeding roller, and the feeding gear section between the feeding roller sections of the feeding roller is used. A one-way clutch may be provided in the drive gear portion for drive transmission.

Even in this case, since the drive transmission to the feeding rollers is performed between the feeding roller sections, even if the feeding rollers are urged, the feeding rollers can perform separate feeding with an even left and right stress balance. realizable. Further, when the one-way clutch is provided in the drive gear portion in this way, the wheel portions of the feed rollers can be connected to each other to keep the distance between the feed rollers constant.

(Appendix 1)
In the above-described embodiment, as a structural example for solving the problems of suppressing the skew chain and stabilizing the separate feeding, each feeding roller portion of the feeding roller is individually used to suppress the skew chain. Although the structure in which the one-way clutch portion of the above is provided and the drive transmission is performed in the gap of at least one of each feed roller portion or each separation roller portion in order to stabilize the separate feed, the present invention has been described. For example, a structure that solves a problem only by stabilizing separate feeding while ensuring the detection accuracy of a document placed on a mounting table is also widely targeted.

That is, the present invention is provided between the rotating shaft, the first and second roller portions provided with a gap in the axial direction of the rotating shaft, and the first and second roller portions provided with a gap in the axial direction of the rotating shaft. A feeding roller or a separating roller characterized by having a gear portion through which the driving force is transmitted, or a separation feeding mechanism or a sheet transporting device equipped with these feeding rollers and the separating roller, and the sheet transporting device. It also covers a wide range of image readers and the like equipped with.

In such an aspect of the present invention, as specifically described in the above-described embodiment, drive transmission is performed in the gear portion of the gap between the first and second rollers in the axial direction of the rotating shaft in the feeding roller or the separating roller. Therefore, if such a roller structure is adopted for the separate feeding mechanism, stable separate feeding operation can be realized, and roller contact pressure for separate feeding can be achieved without interfering with the gear portion between the rollers. Highly accurate document detection can be performed near the part (nip part), and the space between the rollers can be effectively used.

(Appendix 2)
The present invention is not limited to the above-described embodiment, but also broadly covers the following aspects.
(Aspect 1)
Rotation axis and
The first and second roller portions provided with a gap in the axial direction of the rotating shaft, and
A first one-way clutch portion provided between the first roller portion and the rotating shaft,
A second one-way clutch portion provided between the second roller portion and the rotating shaft,
A feed gear portion provided between the first and second roller portions in the axial direction of the rotating shaft and to which a driving force is transmitted, and a feed gear portion.
A feeding roller characterized by being equipped with.

(Aspect 2)
A first wheel portion provided between the first roller portion and the first one-way clutch portion,
A second wheel portion provided between the second roller portion and the second one-way clutch portion,
With
The feed gear portion has a first contact portion capable of contacting the first wheel portion or the first one-way clutch portion in the axial direction of the rotation shaft, and the second wheel portion or the second one-way portion. The feed roller according to the above aspect 1, wherein a second contact portion with which the clutch portion can come into contact is provided.

(Aspect 3)
The main body of the device provided with a loading section for loading multiple sheets, and
A feeding unit that is arranged on the loading surface side of the loading unit and feeds a sheet, and a feeding unit.
A separation unit arranged to face the feeding unit and
A transport unit that transports sheets separated between the feed unit and the separation unit, and a transport unit.
With
The feeding portion is provided between a rotating shaft, first and second roller portions provided with a gap in the axial direction of the rotating shaft, and a first roller portion provided between the first roller portion and the rotating shaft. A driving force is transmitted between the one-way clutch portion, the second one-way clutch portion provided between the second roller and the rotating shaft, and the first and second roller portions in the axial direction of the rotating shaft. A sheet transporting device comprising a feeding gear portion to be provided.

(Aspect 4)
The sheet according to the third aspect, wherein the separation roller is evenly pressed against each roller end portion of the first roller portion and the second roller portion on the feed gear portion side. Transport device.

(Aspect 5)
The apparatus main body includes a bearing portion that receives both ends of the rotary shaft, a drive gear shaft having a drive gear portion connected to the feed gear portion, and a drive motor that rotationally drives the drive gear shaft. Provided,
The drive motor can switch between a forward rotation drive for separately feeding the seat and a reverse rotation drive for returning the seat to the loading portion side.
The seat transfer device according to the fourth aspect, wherein the drive gear shaft is provided with a clutch portion that transmits only the forward rotation drive of the drive motor to the feeding portion.

(Aspect 6)
Equipped with a document detection sensor that detects the presence or absence of a document
The item according to any one of the above aspects 3 to 5, wherein the document detection sensor is extended from the separation roller side so as to enter the gap between the first roller portion and the second roller portion. Sheet transfer device.

(Aspect 7)
The feeding section is provided between a first wheel section provided between the first roller section and the first one-way clutch section, and a second wheel section provided between the second roller section and the second one-way clutch section. Has a wheel part and
In the feed gear portion, the first contact portion with which the first wheel portion or the first one-way clutch portion abuts in the axial direction of the rotation shaft and the second wheel portion or the second one-way clutch portion are in contact with each other. The sheet transport device according to any one of the above aspects 3 to 6, further comprising a second contact portion in contact with the sheet.

(Aspect 8)
The first roller portion is detachably provided with respect to the first wheel portion.
The sheet transfer device according to the seventh aspect, wherein the second roller portion is detachably provided with respect to the second wheel portion.

(Aspect 9)
The first roller portion is fixed to the outer periphery of the first wheel portion, and the first wheel portion is detachably provided with respect to the first core portion provided on the outer circumference of the first one-way clutch portion.
The second roller portion is fixed to the outer periphery of the second wheel portion, and the first wheel portion is detachably provided with respect to the second core portion provided on the outer circumference of the second one-way clutch portion. The sheet transport device according to aspect 7 above.

(Aspect 10)
The feeding gear portion is provided with an outer diameter smaller than the diameter of the first and second roller portions.
Any one of the above aspects 3 to 9, wherein the gear connection portion between the feed gear portion and the drive gear portion overlaps the first and second roller portions in the axial direction of the rotation shaft. The sheet transfer device according to the section.

(Aspect 11)
The sheet transporting device according to any one of the above aspects 3 to 10, wherein the feeding gear portion is provided at a central portion in the longitudinal direction of the rotating shaft.

(Aspect 12)
An image reading device comprising the sheet transporting device according to any one of the above aspects 3 to 11.

(Appendix 3)
The present invention broadly covers not only the relative arrangement of the double feed detection sensor and the movement detection sensor described above, but also the arrangement of the movement detection sensor with respect to the separate feeding unit.

For example, in the above-described embodiment, the feeding roller portion and the separation roller are in contact with each other in the downstream region (gap region) extending from the gap of each feeding roller portion to the downstream side in the feeding direction in the axial direction of the feeding roller shaft. There are dust areas on both sides extending from the pressed left and right nip parts. In this case, the gap region is a region that is less affected by the paper dust than the paper dust region. Therefore, by installing the movement detection sensor corresponding to the gap region (particularly the upstream region of the gap region), it is possible to detect the movement of the document with high accuracy in a place where the influence of paper dust is small.

When the movement detection sensor is arranged as described above, the ultrasonic type double feed detection sensor may be installed in the paper dust area. This is because the double feed detection sensor is less susceptible to the influence of paper dust than the optical movement detection sensor. Such an arrangement of each sensor is also widely targeted as another aspect of the present invention.

A Document feeder S Document 1 Mounting stand 2 Discharge tray 3, 4 Motor 10 First transport section 11 Feed roller 11a One-way clutch 11b Feed roller shaft 11c Friction member 11d Cylindrical section 12 Separation roller 12a Torque limiter 13 Pick arm 14 Document stopper 20 2nd transport unit 21 Transport roller 22 Driven roller 30 3rd transport unit 31 Transport roller 32 Driven roller 40 Double feed detection sensor 50, 60 Media detection sensor 70 Image reading unit 80 Control unit 84 Communication unit 90 Document detection sensor 115 Compression spring 121 Separation swing member 1211 Limiting member 1212 Spring 1213 Elastic member

Claims (6)

A separate feeding unit that separates and feeds sheets one by one,
A transport unit that transports the sheets separated by the separate feed unit along the transport path, and a transport unit.
A sheet detection unit, which is arranged on the downstream side of the separate feeding unit in the sheet feeding direction and detects a sheet, is provided.
The separate feeding section includes a feeding section in which the first and second roller sections are provided at intervals on the rotating shaft, and the feeding section in which pressure is applied to at least a part of the feeding section. It has a separation part that forms a nip part between them,
The sheet detection unit has a double feed detection sensor that detects double feed of the sheet and a movement detection sensor that detects the movement of the seat.
The double feed detection sensor and the movement detection sensor are regions extending downstream from a portion other than the nip portion in the separate feed portion including a gap between the first and second roller portions. and in the downstream region before reaching the conveyor section, we have a test known area of the sheet,
The detection area of the movement detection sensor is a region different from the detection area of the double feed detection sensor.
The double feed detection sensor has a sheet detection region in a first downstream region extending downstream in the sheet feeding direction by the width of the gap between the first and second roller portions.
The movement detection sensor has a sheet transporting region having a sheet detection region in a second downstream region extending downstream in the sheet feeding direction with a width of a portion of the feeding portion where the separating portion is not contacted. Device. The sheet transport device according to claim 1 , wherein the movement detection sensor is arranged closer to the separate feeding unit than the installation position of the double feed detection sensor. The double feed detection sensor is an ultrasonic sensor.
The movement detection sensor is a sensor that detects the movement of the sheet based on the movement amount or the movement direction of the feature points included in the sheet image obtained by photographing the sheet passing through the transport path. The sheet transfer device according to claim 1 or 2. The feeding portion includes a first one-way clutch portion provided between the first roller portion and the rotating shaft, and a second one-way clutch portion provided between the second roller portion and the rotating shaft. The sheet transport device according to any one of claims 1 to 3 , wherein the sheet transport device has. Any of claims 1 to 4 , wherein the feeding portion has a feeding gear portion provided between the first and second roller portions in the axial direction of the rotating shaft and to which a driving force is transmitted. The sheet transport device according to item 1. The sheet transport device according to any one of claims 1 to 5 is provided, and an image reading sensor for reading an image of the sheet to be transported is provided in the transport path of the sheet transport device. Image reader.

Images