JP7549514B2 - Sheet conveying device and image reading device - Google Patents

Description

The present invention relates to a sheet transport device that transports a sheet and an image reading device equipped with the same.

As shown in FIG. 24, a conventional document transport device is known in which a document S is fed by a feed roller 1011, the document S is transported by a transport roller 1021, and an image of the document S is read by a reading sensor 1070. This document transport device is described as a conventional example in Patent Document 1. The feed roller 1011 and the transport roller 1021 are driven by a feed motor 1003 and a transport motor 1004, respectively. A medium detection sensor 1060 is disposed downstream of the transport roller 1021 and upstream of the reading sensor 1070 in the sheet transport direction. In order to reliably read the document S from the leading edge to the trailing edge by the reading sensor 1070, the document S needs to be transported with a predetermined interval (hereinafter referred to as the paper interval).

Specifically, the document transport device feeds the document S by rotating the feed roller 1011 while keeping the transport roller 1021 constantly rotating, and stops driving the feed roller 1011 when the leading edge of the document S passes the media detection sensor 1060. Then, when the trailing edge of the document transported by the transport roller 1021 passes the media detection sensor 1060, the feed roller 1011 is driven again, and the next document is fed by the feed roller 1011.

Patent Document 1 also proposes an image reading device that has a normal mode in which the feed roller repeatedly rotates and stops to transport the document, and a thick paper mode in which the feed roller continues to rotate at a low speed to transport the document. In the thick paper mode, the feed roller rotates at a slower speed than the second and third transport units that are located downstream of the feed roller in the sheet transport direction.

JP 2017-95228 A

However, in the conventional example described above with reference to FIG. 24, when a thick document is transported, the transport of the document may stop when the leading edge of the document catches the media detection sensor 1060. This is because the feed roller 1011 stops when the leading edge of the document catches the media detection sensor 1060, reducing the force for transporting the thick document, causing the transport roller 1021 to slip relative to the document, or the transport motor 1004 to lose synchronization.

In addition, in the image reading device of Patent Document 1, in the thick paper mode, the paper feed roller continues to rotate at all times, causing the paper feed motor to heat up, making it impossible to obtain the motor characteristics specified in the specifications, and shortening the life of the paper feed motor.

The present invention aims to provide a sheet transport device that can suppress the temperature rise of the drive source and can transport sheets stably, and an image reading device equipped with the same.

The present invention is characterized in that the sheet conveying device includes a loading section on which sheets are loaded, a feeding rotor that feeds the sheets loaded on the loading section, a separation rotor that forms a separation nip together with the feeding rotor and separates the sheets one by one at the separation nip, a discharge rotor pair that is disposed downstream of the separation nip in the sheet conveying direction and has a discharge nip that discharges the sheets fed by the feeding rotor, a drive source that can drive the feeding rotor, and a conveying mode in which, when a booklet-like sheet having a binding margin is conveyed in an open state, the feeding rotor is driven to feed the sheets loaded on the loading section, and when the binding margin of the sheet passes through the discharge nip of the discharge rotor pair and the sheet is sandwiched by the discharge nip, the drive from the drive source to the feeding rotor is cut off.

The present invention also provides a sheet transport device that includes a loading section on which sheets are loaded, a feeding rotor that feeds the sheets loaded on the loading section, a separation rotor that forms a separation nip together with the feeding rotor and separates the sheets one by one at the separation nip, a discharge rotor pair that is disposed downstream of the separation nip in the sheet transport direction and has a discharge nip that discharges the sheets fed by the feeding rotor, and a drive source that can drive the feeding rotor. When a booklet-like sheet having a binding margin is transported in an open state, the feeding rotor is driven to feed the sheets loaded on the loading section, and the drive from the drive source to the feeding rotor is cut off when the rear end of the sheet passes through the separation nip and the sheet is sandwiched by the discharge nip.

The present invention also provides a sheet conveying device, which includes a loading section on which sheets are loaded, a feeding rotor that feeds the sheets loaded on the loading section, a separation rotor that forms a separation nip together with the feeding rotor and separates the sheets one by one at the separation nip, a pair of discharge rotors that are disposed downstream of the separation nip in the sheet conveying direction and have a discharge nip that discharges the sheets fed by the feeding rotor, a drive source that can drive the feeding rotor, and a conveying mode in which, when conveying a sheet having a first portion having a first thickness and a second portion having a second thickness thicker than the first thickness at different positions in the sheet conveying direction, the feeding rotor is driven to feed the sheet loaded on the loading section, and the drive from the drive source to the feeding rotor is cut off when the second portion of the sheet passes through the discharge nip of the pair of discharge rotors and the sheet is sandwiched by the discharge nip.

This invention makes it possible to suppress the temperature rise of the drive source and transport the sheet stably.

1 is an overall schematic view showing an image reading apparatus according to a first embodiment. FIG. 2 is a cross-sectional view showing the image reading device with the upper unit closed. FIG. 2 is a cross-sectional view showing the image reading device with the upper unit opened. FIG. 4 is a cross-sectional view showing a separation mechanism of the image reading device. FIG. 11 is a cross-sectional view showing the separation mechanism when the holder is transported. FIG. 4 is a cross-sectional view showing a document detection structure of the paper feed section. FIG. 4 is a cross-sectional view showing a document detection structure of the paper feed section. FIG. 4 is a perspective view showing a document detection structure of the paper feed section. FIG. FIG. FIG. 4 is a flowchart showing paper feed and transport control. FIG. FIG. FIG. FIG. 13 is a perspective view showing how a passport is placed in the holder. 10 is a flowchart showing paper feed and transport control according to the second embodiment. FIG. 11 is an overall schematic view showing an image reading apparatus according to a third embodiment. FIG. 2 is a cross-sectional view showing a paper feed drive system of the image reading apparatus. FIG. 2 is a cross-sectional view showing a transport drive system of the image reading apparatus. FIG. 5 is a cross-sectional view showing the conveyance drive system of the image reading apparatus when the drive unit is rotated in the reverse direction. FIG. 4 is a flowchart showing a paper feeding operation of the image reading apparatus. FIG. 1 is a cross-sectional view showing a conventional document transport device.

First Embodiment
The first embodiment will be described with reference to Figures 1 to 16. Figure 1 is a schematic diagram of an image reading device A according to the first embodiment.

[Apparatus configuration]
The image reading device A is a device that transports one or more documents S loaded on a loading platform 1 as a loading section one by one into the device along a transport path RT, reads the images of the documents, and discharges them onto a discharge tray 2. The documents S to be read are, for example, sheets such as office paper, checks, banknotes, business cards, cards, etc., and may be thick or thin sheets. Examples of cards include insurance cards, driver's licenses, and credit cards. The documents S also include booklets such as passports with built-in IC chips.

When a booklet is the target, the holder 100 described below can be used. By placing a booklet in an open state in the holder 100 and placing it on the mounting table 1, the booklet is transported together with the holder 100, and the image on the booklet can be read.

[Upper unit]
Fig. 2 is a schematic cross-sectional view of the image reading device A according to the first embodiment. The image reading device A is composed of an upper unit 103 and a lower unit 104, and the upper unit 103 is attached to the lower unit 104 so as to be rotatable about a main body hinge 105. Fig. 3 shows a state in which the upper unit 103 has been rotated to release the transport path RT in Fig. 1. In this state, a user can clear jammed documents, clean rollers, etc.

[First conveying section]
As shown in FIG. 1, a first transport section 10 is provided to feed the document S along the transport path RT. The first transport section 10 includes a feed roller 11 as a feed rotor, and a separation roller 12 as a separation rotor arranged opposite the feed roller 11. The separation roller 12 forms a separation nip N1 together with the feed roller 11, and transports the document S on the placement table 1 one by one in the sheet transport direction D1 at the separation nip N1. A driving force is transmitted from the drive section 3 to the feed roller 11 via the transmission section 5, and the feed roller 11 is driven to rotate in the direction of the arrow in the figure (the forward direction for transporting the document S along the transport path RT). The drive section 3 as a drive source is, for example, a motor capable of driving the feed roller 11. The transmission section 5 is, for example, an electromagnetic clutch, and connects and disconnects the driving force from the drive section 3 to the feed roller 11.

[Drive unit]
In this embodiment, for example, the transmission unit 5 connecting the drive unit 3 and the paper feed roller 11 is in a state where the driving force is normally transmitted (hereinafter, ON), and is in a state where the driving force is cut off (hereinafter, OFF) when the document S is fed backward during a multi-feed retry, which will be described later. When the transmission of the driving force is cut off by the transmission unit 5, the paper feed roller 11 is in a freely rotatable state. Note that such a transmission unit 5 does not need to be provided when the paper feed roller 11 is driven in only one direction.

[Separation mechanism]
The separation roller 12, which is disposed opposite the paper feed roller 11, is a roller for separating the documents S one by one, and is in contact with the paper feed roller 11 with a constant pressure. As shown in Fig. 4, the separation roller 12 is rotatably supported by a separation float 121, which is rotatably supported around a shaft portion 121a. A compression spring 122 applies a biasing force to the separation float 121 so that the separation roller 12 is in contact with the paper feed roller 11 with pressure, and the separation roller 12 is maintained in contact with the paper feed roller 11 with pressure.

As shown in FIG. 1, the separation roller 12 receives a driving force from the drive unit 3 via the torque limiter 12a, and is driven to rotate in the direction of the solid arrow (the opposite direction to the forward direction of the paper feed roller 11). Because the transmission of the driving force to the separation roller 12 is restricted by the torque limiter 12a, when the separation roller 12 is in contact with the paper feed roller 11, it rotates in the direction of the paper feed roller 11 (the direction of the dashed arrow). As a result, when multiple documents S are transported to the pressure contact area between the paper feed roller 11 and the separation roller 12, two or more documents S are blocked so that they are not transported downstream, leaving only one.

In this embodiment, the separation mechanism is made up of the separation roller 12 and the paper feed roller 11, but such a separation mechanism is not necessarily required, and any feed mechanism that sequentially feeds the originals S one sheet at a time to the transport path RT will suffice. In addition, when a separation mechanism is provided, instead of a configuration such as the separation roller 12, a separation pad that applies friction to the originals S may be pressed against the paper feed roller 11 to provide a similar separation function.

[Thickness detection sensor]
In this configuration, the thickness of the original S is detected using a thickness detection sensor 123 as a thickness detection unit that detects the thickness of the original S. As shown in Fig. 4, a flag portion 121b is provided on the separation float 121, and the thickness detection sensor 123 for the original S is provided in the vicinity of the flag portion 121b. In this embodiment, a photointerrupter is used as the original thickness detection sensor. As another example, an encoder may be used instead of the photointerrupter.

The separation float 121 swings around the shaft 121a in the direction away from the feed roller 11 in response to the thickness of the fed document S. When a document S of a certain thickness or more is fed, the flag 121b enters the thickness detection sensor 123, detecting that the displacement is greater than a certain amount, and determining that the document is a passport. Figure 5 shows the state when the holder 100 described later is fed. When the holder 100 enters the pressure contact portion between the feed roller 11 and the separation roller 12, the separation roller 12 rotates around the shaft 121a and rises up in response to the thickness of the holder 100, and the flag 121b enters the thickness detection sensor 123. As a result, the thickness detection sensor 123 detects a displacement greater than a certain amount, determining that the document is a passport, and switching to conveyance in passport mode. If the displacement of the thickness detection sensor 123 is less than a certain amount as a result of the detection of thick paper by the thickness detection sensor 123, switching to conveyance in normal mode.

In this embodiment, the thickness of the fed document S is detected and the transport control is switched, but it is also possible to provide two transport control means without detecting the thickness of the document S, and have the user select one of the transport control means depending on the thickness of the document S before feeding. These two transport control means are the normal mode and the passport mode. Documents S transported in the normal mode are, for example, office paper, magazines, checks, paper bills, business cards, etc.

[Passport length detection]
The dimensions of a passport vary depending on the country of manufacture. In this configuration, the IC chip in the passport is read and collated with a pre-registered database based on the information on the country of manufacture to identify the dimensions of the passport. As shown in FIG. 1, a short-range wireless reader unit 130 is disposed on the mounting base 1 as an acquisition unit capable of acquiring nationality information from the IC chip. A control unit 80 (described later) acquires the length of the passport by reading the nationality information from the IC chip of the passport with the short-range wireless reader unit 130. The database storing information related to passports may be provided inside the image reading device or on an external server.

In this embodiment, the length of the passport is detected using the short-range wireless reader unit 130 to switch the timing of stopping the drive unit 3, but this is not limited to the above. For example, instead of detecting the length of the document S, a selection item for the country of manufacture of the passport may be provided in the driver settings, and the user may select the country of manufacture of the passport to be transported before feeding. In addition, the length of the passport in the sheet transport direction D1 may be obtained from the user's operation on the operation unit 83 described below. It may also be preset according to the country of shipment of the product.

[Document detection structure of paper feed section]
In order to detect the presence or absence of the document S on the placement table 1, a document detection sensor 90 is provided upstream of the paper feed roller 11. The document detection sensor 90 is a lever-type sensor. As another example, an optical sensor such as the medium detection sensors 50 and 60 described below may be used.

Figure 6 shows a state where there is no document S on the placement table 1, and Figure 7 shows a state where there is a document S on the placement table 1. The lever portion 90a of the document detection sensor 90 is supported by the upper unit 103 so as to be rotatable around the shaft portion 90b. As shown in Figure 7, when the document S is set in the paper feed tray so that the leading edge of the document S abuts against the claw portion 15a of the document stopper 15, the leading edge of the document pushes the lever portion 90a, and the presence of the document S is detected.

A roller cover 13 that covers the feed roller 11 is provided around the feed roller 11. A guide 14 is provided on the roller cover 13 to guide the document S so that the tip of the document S does not get caught on the feed roller 11 when the document S is set in the feed tray. The guide 14 is supported rotatably around the shaft 14a and is biased by a spring (not shown) in a direction that lifts the document S away from the feed roller 11, with the tip 14b abutting against the receiving portion 13a of the roller cover 13 to stop the rotation. The position of the guide 14 can be precisely maintained by positioning the tip 14b, which is far from the shaft 14a, with the receiving portion 13a.

As shown in FIG. 8, the guide 14 has three arms 14c, which are located in the middle and on both sides of the two feed rollers 11. By providing an arm 14c in the middle of the two feed rollers 11, when setting a document S that is weak, such as thin paper, the document S is prevented from bending and hitting the feed rollers.

As shown in FIG. 8, the document stopper 15 has three claws 15a and is supported rotatably around a shaft 15b. The document stopper 15 is driven by a drive mechanism (not shown) and moves to open the transport path when the document S is transported, allowing the document S to be transported.

The leading edge of the document S set as shown in FIG. 7 strikes against the claw portion 15a of the document stopper 15. To prevent the claw portion 15a of the document stopper 15 from bending due to the force of the document S striking it, the roller cover 13 is provided with a rib-shaped portion 13b as shown in FIG. 9. The rib-shaped portion 13b supports the downstream side of the leading edge 15c of the claw portion 15a, thereby preventing the claw portion 15a from bending.

As shown in Figures 9 and 10, the tip 90c of the lever portion 90a of the document detection sensor 90 is positioned downstream in the transport direction from the line connecting the center of the feed roller 11 and the center of the separation roller 12. As a result, when the upper unit 103 is closed from the open state (as shown in Figure 3) after clearing a jam, etc., if a document S is in the transport path, the tip 90c of the document detection sensor 90 moves downstream while contacting the document S. This prevents the tip 90c from breaking through the document S.

[Second conveying section]
1, the second transport section 20, which is located downstream of the first transport section 10 in the transport direction, includes a drive roller 21 and a driven roller 22 driven by the drive roller 21, and is capable of transporting the document S transported from the first transport section 10 downstream. A driving force is transmitted to the drive roller 21 from a drive section 4 such as a motor, and the drive roller 21 is driven to rotate in the direction of the arrow in the figure. The driven roller 22 is in contact with the drive roller 21 with a constant pressure, and rotates together with the drive roller 21. The driven roller 22 may be configured to be biased against the drive roller 21 by a biasing unit (not shown) such as a spring.

[Third conveying section]
The third conveying section 30, which is a pair of discharge rotors downstream of the second conveying section 20 in the sheet conveying direction D1, includes a drive roller 31 and a driven roller 32 driven by the drive roller 31. The drive roller 31 and the driven roller 32 form a discharge nip N2, which discharges the document S conveyed from the second conveying section 20 to the discharge tray 2. In other words, the third conveying section 30 functions as a discharge mechanism. A driving force is transmitted from a drive unit 4 such as a motor to the drive roller 31, and the drive roller 32 is rotated in the direction of the arrow in the figure. The driven roller 32 is pressed against the drive roller 31 with a constant pressure and rotates with the drive roller 31. The driven roller 32 may be configured to be biased against the drive roller 31 by a biasing unit (not shown) such as a spring.

[Double feed detection]
The multi-feed detection sensor 40 is an example of a detection sensor (a sensor that detects the behavior or state of the document) for detecting when the document S such as paper is stuck to each other due to static electricity or the like and passes through the first transport section 10 (i.e., when the document S is transported overlapping). The multi-feed detection sensor 40 is disposed between the first transport section 10 and the second transport section 20 in the transport direction. Various types of multi-feed detection sensor 40 can be used, but in this embodiment, it is an ultrasonic sensor and includes an ultrasonic transmitter 41 and a receiver 42. The attenuation of the ultrasonic wave transmitted from the transmitter 41 and passing through the document S differs depending on whether the document S such as paper is transported overlapping or transported one by one, and the multi-feed detection sensor 40 detects multi-feed based on this principle.

[Media detection sensor]
The medium detection sensor 50 arranged downstream in the transport direction from the double feed detection sensor 40 is an example of an upstream detection sensor (a sensor that detects the behavior or state of the document) arranged upstream from the second transport unit 20 and downstream from the first transport unit 10. The medium detection sensor 50 detects the position of the document S transported by the first transport unit 10, more specifically, whether or not the end of the document S has reached or passed the detection position of the medium detection sensor 50. Various types of medium detection sensor 50 can be used, but in this embodiment, it is an optical sensor that includes a light emitting unit 51 and a light receiving unit 52, and detects the document S on the principle that the intensity of received light (amount of received light) changes when the document S reaches or passes through.

In this embodiment, the media detection sensor 50 is provided downstream of and near the multi-feed detection sensor 40 so that when the leading edge of the document S is detected by the media detection sensor 50, the document S has reached a position where the multi-feed detection sensor 40 can detect the multi-feed. Note that the media detection sensor 50 is not limited to the optical sensor described above, and may be, for example, a sensor (such as an image sensor) that can detect the edge of the document S, or a lever-type sensor that protrudes into the transport path RT.

A media detection sensor 60, separate from the media detection sensor 50, is disposed upstream of the image reading unit 70. The media detection sensor 60 is an example of a downstream detection sensor disposed downstream of the second transport unit 20, and detects the position of the document S transported by the second transport unit 20. Various types of media detection sensor 60 can be used, but in this embodiment, like the media detection sensor 50, it is an optical sensor, and includes a light-emitting unit 61 and a light-receiving unit 62. The media detection sensor 60 as a detection unit detects the position of the document S based on the principle that the received light intensity (received light amount) changes when the document S arrives or passes by.

[Image reading unit]
The image reading unit 70 as a reading section located downstream of the medium detection sensor 60, for example, optically scans, converts into an electrical signal, and reads as image data, and is equipped with a light source such as an LED, an image sensor, a lens array, etc. In this embodiment, a contact image sensor is used for the image reading unit 70, and one is arranged on each side of the transport path RT to read the front and back sides of the document S. However, a configuration in which one is arranged on only one side of the transport path RT to read only one side of the document S may also be used. Also, in this embodiment, the image reading units 70 are structured to be arranged opposite each other on both sides of the transport path RT, but they may also be arranged, for example, spaced apart in a direction along the transport path RT.

Also, at least one of the two image reading units 70 may be supported so as to be swingable in the thickness direction of the original S. For example, one image reading unit 70 is fixed to the lower unit 104, and the other image reading unit is supported in the upper unit 103 so as to be swingable in a direction perpendicular to the transport surface, and is biased by a spring or the like to abut against the opposing image reading unit 70. With this configuration, when the original S passes, the image reading unit 70 on the upper unit 103 side floats according to the thickness of the original S, making it possible to read images from thin to thick paper.

[Control unit]
Next, the control unit 80 in this embodiment will be described. Fig. 11 is a block diagram showing the control unit 80. As shown in Fig. 11, the control unit 80 has 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 image reading device A by executing a program stored in the storage unit 82. The storage unit 82 is composed of, for example, a RAM, a ROM, etc. The operation unit 83 is composed of, for example, a switch, a touch panel, etc., and accepts operations from the user.

The communication unit 84 is an interface that communicates information with an external device. If the external device is a PC (personal computer), the communication unit 84 can be, for example, a USB interface or a SCSI interface. In addition to such a wired communication interface, the communication unit 84 may be a wireless communication interface, or may have both wired and wireless communication interfaces.

The interface unit 85 is an I/O interface that inputs and outputs data to and from the actuator 86 and the sensor 87. The actuator 86 includes the drive units 3 and 4, and a document stopper, drive roller, cam member, etc., which are members that are driven via a timing belt and gears described below. The sensor 87 includes the double feed detection sensor 40, the media detection sensors 50 and 60, the image reading unit 70, the document detection sensor 90, and the thickness detection sensor 123, etc.

[Driven by receiving a start instruction from a PC]
Next, a description will be given of the basic operation of the image reading device A. When the control unit 80 receives an instruction to start image reading from, for example, an external personal computer to which the image reading device A is connected, it starts driving the first conveying unit 10 to the third conveying unit 30. The documents S loaded on the placement table 1 are conveyed one by one starting from the document S located at the bottom.

[Multi-feed control]
During the transport, the document S is judged by the multi-feed detection sensor 40 whether or not there is a multi-feed, and if it is judged that there is no multi-feed, the transport continues. If it is judged that there is a multi-feed, a multi-feed retry is performed, the transport is stopped, or the intake of the subsequent document S by the first transport unit 10 is stopped, and the document S in the multi-feed state may be discharged as it is. The multi-feed retry is a function to reverse the document detected as a multi-feed and then feed it again. When a multi-feed is detected, if the transmission unit 5 is turned OFF, the feed roller 11 becomes freely rotatable, and rotates with the rotation of the separation roller 12, allowing the document S to be reversed.

[Start reading according to the output of the media detection sensor]
The control unit 80 starts reading the image of the document S conveyed by the second conveying unit 20 by the image reading unit 70 at a timing based on the detection result of the medium detection sensor 60, temporarily stores the read image, and sequentially transmits it to the external computer. The document S from which the image has been read is discharged to the discharge tray 2 by the third conveying unit 30, and the image reading process of the document S is completed.

[Paper feed and transport control]
Here, in the image reading device A of this embodiment, the image is read by the image reading unit 70 arranged between the second conveying section 20 and the third conveying section 30, so the second conveying section 20 and the third conveying section 30 convey the document S at a constant speed. If the conveying speed of the first conveying section 10 is set to a speed faster than the speeds of the second conveying section 20 and the third conveying section 30, the document S will bend when it is nipped by both the first conveying section 10 and the second conveying section 20. For this reason, the conveying speed of the first conveying section 10 may be set to be equal to or lower than the speeds of the second conveying section 20 and the third conveying section 30. In this embodiment, the conveying speed of the first conveying section 10 is set to be equal to the conveying speeds of the second conveying section 20 and the third conveying section 30.

Next, the operation flow of the paper feed/transport control of image reading device A will be described with reference to FIG. 12. When paper feed/transport control is started, control unit 80 receives an instruction to start image reading, for example, from an external personal computer to which image reading device A is connected (step S11). Next, control unit 80 determines whether or not there is a document S on placement table 1 according to the detection result of document detection sensor 90 (step S12).

If it is determined that there is no document S on the placement table 1 (step S12: No), the control unit 80 displays a message or the like to that effect on the external personal computer or the display panel of the operation unit 83 (step S13), and ends the paper feed and transport control. If it is determined that there is a document S on the placement table 1 (step S12: Yes), the control unit 80 determines whether the document S on the placement table 1 is a passport with an IC chip or not, depending on the detection result of the short-range wireless reader unit 130 (step S14). If it is determined that the document on the placement table 1 is not a passport with an IC chip (step S14: No), the process proceeds to step S16.

If the document S on the placement table 1 is determined to be a passport with an IC chip (step S14: Yes), the control unit 80 acquires nationality information from the IC chip of the passport and drives the drive unit 4 (steps S15, S16). Furthermore, the control unit 80 turns on the transmission unit 5 and drives the drive unit 3 (steps S17, S18). Then, the document S is fed by the feed roller 11 and the separation roller 12 driven by the driving force from the drive unit 3, and the leading edge of the document S passes the media detection sensor 50 (step S19). The sheet conveying speed in the separation nip N1 at this time is defined as conveying speed V1. In this embodiment, the conveying speeds of the second conveying unit 20 and the third conveying unit 30 are also set to the sheet conveying speed V1 in the separation nip N1.

Next, the control unit 80 judges whether the thickness of the document S is equal to or greater than a predetermined thickness according to the detection result of the thickness detection sensor 123 (step S20). If the thickness of the document S is less than the predetermined thickness (step S20: No), the control unit 80 controls the transport of the image reading device A in the normal mode. That is, steps S11 to S24 correspond to the transport control in the normal mode. If the thickness of the document S is equal to or greater than the predetermined thickness (step S20: Yes), the control unit 80 controls the transport of the image reading device A in the passport mode. That is, steps S11 to S18 and S25 to S28 correspond to the transport control in the passport mode. The normal mode is a transport mode suitable for transporting a document S such as a plain paper, and the passport mode is a transport mode suitable for transporting a document S such as a booklet-shaped passport having a binding margin Sa (see FIG. 16) in an open state. Note that if it is detected in step S14 that the document S is a passport with an IC card, the determination in step S20 may be skipped and the process may proceed to step S25.

In normal mode (steps S11 to S24), when the leading edge of the document S passes the media detection sensor 60 (step S21), the control unit 80 stops the drive unit 3 (step S22). As a result, the document S is transported by the second transport unit 20 and the third transport unit 30, and the first transport unit 10, which is composed of the feed roller 11 and the separation roller 12, rotates in response to the document S. At this time, a predetermined time after the media detection sensor 60 detects the leading edge of the document S, the image reading unit 70 starts reading the image.

When the rear end of the document S passes the media detection sensor 60 (step S23), the image reading by the image reading unit 70 ends after a predetermined time, and the control unit 80 determines whether or not the document S is present on the placement table 1 based on the detection result of the document detection sensor 90 (step S24). If it is determined that the document S is present on the placement table 1 (step S24: Yes), the process returns to step S18. If it is determined that the document S is not present on the placement table 1 (step S24: No), the process proceeds to step S29.

On the other hand, in the passport mode (steps S11 to S18, S25 to S28), when the leading edge of the document S passes the media detection sensor 60 (step S25), the control unit 80 drives the drive unit 3 for a predetermined number of pulses and then stops the drive unit 3 (step S26). In other words, the control unit 80 determines the timing to stop the drive unit 3 based on the media detection sensor 60 detecting the leading edge of the sheet (for example, the leading edge SL of the holder 100 (see FIG. 16)). This predetermined number of pulses is the number of drive pulses of the drive unit 3 required to transport the document S until the binding margin portion Sa (see FIG. 16) of the passport, which is the document S, passes the discharge nip N2 of the third transport unit 30. In other words, based on the sheet transport speed of the third transport unit 30, the drive from the drive unit 3 to the feed roller 11 is cut off a predetermined time after the media detection sensor 60 detects the leading edge of the sheet fed by the feed roller 11. As in normal mode, image reading by the image reading unit 70 begins a predetermined time after the media detection sensor 60 detects the leading edge of the document S.

In this embodiment, as shown in FIG. 16, a booklet-like passport may be placed in the holder 100 for transport. When transporting a booklet-like passport in the holder 100, the binding margin of the passport also bears the greatest transport load. Since the size of passport booklets differs from country to country, the distance from the tip of the holder 100 to the binding margin of the passport also differs from country to country. The length of the holder 100 in the transport direction and the width relative to the transport direction are preset to a predetermined length according to the type of passport, etc., to be stored.

For example, consider the case of transporting a Japanese passport. In the case of a Japanese passport, the distance from the tip of the holder 100 to the binding margin Sa (see FIG. 16) of the passport is 88 mm, and the distance from the medium detection sensor 60 to the discharge nip N2 of the third transport unit 30 in the image reading device A of this embodiment is set to 41.8 mm. Therefore, the control unit 80 stops the drive unit 3 after transporting the holder 100 129.8 mm after the tip of the holder 100 passes the medium detection sensor 60, that is, when the binding margin Sa passes the discharge nip N2 and the holder 100 is sandwiched by the discharge nip N2. This cuts off the drive from the drive unit 3 to the paper feed roller 11. The distance by which the holder 100 is transported from the detection of the tip of the holder 100 by the medium detection sensor 60 to the stopping of the drive unit 3, that is, the timing to stop the drive unit 3, is determined from the nationality information of the passport acquired using the short-range wireless reader unit 130. If the leading edge SL of the holder 100 has a portion that does not contain the document S, such as a glue margin, it is preferable to transport the holder 100 by an additional transport amount equal to the length in the transport direction before stopping the drive unit 3. Also, for example, if the medium detection sensor 60 is an optical sensor and the holder 100 is transparent, the holder 100 will not be detected by the medium detection sensor 60, but the medium detection sensor 60 will still detect the leading edge of the document S. Therefore, by transporting the holder 100 by the aforementioned transport amount, the binding margin Sa of the passport can be made to reach the discharge nip N2.

Then, when the rear end of the document S (for example, the rear end ST of the holder 100 (see FIG. 16)) passes the media detection sensor 60 (step S27), the image reading by the image reading unit 70 ends after a predetermined time, and the control unit 80 judges whether the document S is on the placement table 1 based on the detection result of the document detection sensor 90 (step S28). If it is judged that the document S is on the placement table 1 (step S28: Yes), the process returns to step S18. That is, the control unit 80 transmits the drive from the drive unit 3 to the paper feed roller 11 based on the detection of the rear end of the document S by the media detection sensor 60. If it is judged that the document S is not on the placement table 1 (step S28: No), the process proceeds to step S29. Note that if it is judged that the document S is on the placement table 1 in step S28, the process may be configured to return to step S14.

In step S29, the control unit 80 stops the drive unit 3 and turns off the transmission unit 5 (step S29). Next, the control unit 80 stops the drive unit 4 (step S30) and ends the paper feed and transport control. However, the cardboard mode of the above-mentioned Patent Document 1 has a problem in that transport errors such as double feeding are more likely to occur than in the normal mode.

The transport error will be described with reference to Fig. 13 to Fig. 15. In ideal document transport, as shown in Fig. 13, when the nth document d _n is being fed, the leading edge of the next document, document d _n+1 , stops at point P, which is approximately the center of the roller nip between the feed roller 11 and the separation roller 12. However, when a stack of documents in which the adhesion between the papers is strong is fed, as shown in Fig. 14, when document d _n is being fed, the leading edge of document d _n+1 stops at a point downstream of point P. This is because document d _n+1 is in close contact with document d _n and is dragged into the paper by document d _n (hereinafter, referred to as dragging). When feeding of document d _n+1 is started from this dragging position, the paper interval becomes shorter, and if it becomes smaller than the specified paper interval, a paper jam error is generated and transport is stopped. When transport is performed in the thick paper mode of Patent Document 1, when feeding of document d _n+1 begins from this lead-in position, the leading edge of document d _n+1 overlaps with the trailing edge of document d _n , as shown in Figure 15. If this overlapping portion of the documents passes through the overlapping detection sensor 40, a overlapping error occurs.

However, in the normal mode, the feed roller 11, which has been stopped after the trailing edge of the document has passed the medium detection sensor 60, is rotated to feed the next document. Therefore, the feeding of document d n+ ₁ does not start in the state where the trailing edge of document d _n and the leading edge of document d _n+1 overlap as described above, and since there is a sufficient gap between the documents, there are fewer double feed errors and paper jam errors than in the thick paper mode. Also, in the normal mode, when the trailing edge of document d _n passes point P, the distortion of the rubber of the separation roller 12 and the force charged to the torque limiter of the separation roller 12 are released, and the document stack from document d _n+1 onwards is returned in the upstream direction by this force. At this time, any documents that have been dragged in are also returned. As a result, there are fewer paper jam errors and double feed errors than in the thick paper mode.

On the other hand, in the passport mode of this embodiment, the rotation of the feed roller 11 stops when the rear end of the document d _n passes the point P, and when the rear end of the document d _n passes the medium detection sensor 60, the feed roller 11 rotates to feed the next document. As in the normal mode described above, feeding of document d _n+1 does not start in a state where the rear end of document d _n and the front end of document d _n+1 overlap, and a sufficient gap is provided between the documents, so there are fewer double feed errors and paper jam errors compared to the thick paper mode of Patent Document 1. As a result, the passport can be transported stably and continuously.

The holder 100 is used to prevent the booklets from being turned over or folded when they are transported, and the booklets are placed in the holder 100 in an open state as shown in FIG. 16. Thick documents such as passports in the holder 100 can be transported stably because the feed roller 11 continues to drive even if the leading edge of the document catches the media detection sensor 60, so the transport force does not decrease.

In this embodiment, the control unit 80 detects the thickness of the fed document, and if it determines that it is less than a predetermined thickness, it transports the document in normal mode, and if it determines that it is equal to or greater than the predetermined thickness, it transports the document in passport mode as the transport mode. In passport mode, for example, when the binding margin portion Sa of the open passport contained in the holder 100 passes through the discharge nip N2 and the holder 100 is clamped by the discharge nip N2, the drive unit 3 is stopped and the drive to the feed roller 11 is cut off.

Therefore, until the binding margin Sa, which is particularly thick and causes a large transport load, passes through the discharge nip N2, the paper feed roller 11 is driven by the drive unit 3, and the paper feed roller 11 assists the second transport unit 20 and the third transport unit 30 in transporting the holder 100. As a result, slippage between the second transport unit 20 and the third transport unit 30 and the holder 100, and loss of synchronism of the drive unit 4 are suppressed, and transport problems such as jamming of the holder 100 can be reduced.

Furthermore, when the rear end ST of the holder 100 passes the media detection sensor 60, the driving of the drive unit 3 is resumed and the subsequent document (e.g., another holder) is fed. In this way, in the passport mode, the drive unit 3 does not continue to be driven, but there is a timing at which the drive unit 3 stops, which suppresses the temperature rise of the drive unit 3, ensures that the specified motor characteristics are obtained, and extends the life of the drive unit 3. Therefore, it is possible to provide a sheet conveying device and image reading device A that suppresses the temperature rise of the drive unit 3 and enables stable sheet conveyance.

The sheet conveying device is composed of the parts of the image reading device A excluding the image reading unit 70. In other words, the image reading device A has a sheet conveying device and an image reading unit 70 that reads the sheet conveyed by the sheet conveying device.

In addition, in this embodiment, the case where a passport having a binding margin Sa stored in the holder 100 is transported has been described as an example, but the present invention is not limited to this. For example, consider the case where a sheet having a first portion (e.g., a portion other than the binding margin Sa) having a first thickness and a second portion (e.g., the binding margin Sa) having a second thickness thicker than the first thickness is transported at different positions in the sheet transport direction D1.

In this case, a transport mode may be executed in which the sheet is fed by driving the feed roller 11, and the drive unit 3 is stopped when the second portion of the sheet passes through the discharge nip N2 and is clamped by the discharge nip N2. In this way, the transport mode of the present invention may be applied not only to the case of transporting an open passport contained in the holder 100, but also, for example, when transporting an open passport in booklet form that is not contained in the holder 100. The transport mode of the present invention may also be applied when transporting an open booklet other than a passport, or an envelope having a folded and overlapping lid portion as the second portion.

In addition, when the thickness of the fed document is detected and it is determined that it is equal to or greater than a predetermined thickness, the document is transported in passport mode as the transport mode. However, the present invention is not limited to this, and the flow from step S25 onwards in FIG. 12 may be configured to be executed based on whether passport mode, thick paper mode, etc. is selected. In this case, if passport mode, thick paper mode, etc. is not selected, the control from step S21 onwards may be executed. The selection of passport mode or thick paper mode may be selected and input by the user from an operation unit provided in image reading device A or an external computer, or the control unit 80 or the like may determine whether to automatically execute the selection based on certain conditions (the determination of the thickness of document S in step S20 in FIG. 12 is one example).

Second Embodiment
Next, a second embodiment of the present invention will be described, which differs from the first embodiment only in the timing of stopping the driving unit 3 in the passport mode. Therefore, the same configuration as the first embodiment will not be illustrated or described, or will be described with the same reference numerals in the drawings.

Figure 17 is a flowchart showing paper feed and transport control according to the second embodiment. Compared to Figure 12 described above, Figure 17 only replaces step S26 in Figure 12 with step S40. Therefore, the following will mainly explain step S40 in Figure 17.

In passport mode (steps S11 to S18, S25, S40, S27, S28), when the leading edge of the document passes the media detection sensor 60 (step S25), the control unit 80 drives the drive unit 3 a predetermined number of pulses and then stops the drive unit 3 (step S40). This predetermined number of pulses is the timing when the trailing edge ST (see FIG. 16) of the document holder 100 passes through the separation nip N1 of the first transport unit 10.

When the trailing edge of the document passes the media detection sensor 60 (step S27), the control unit 80 determines whether or not there is a document on the placement table 1 based on the detection result of the document detection sensor 90 (step S28). If it is determined that there is a document on the placement table 1 (step S28: Yes), the process returns to step S18. If it is determined that there is no document on the placement table 1 (step S28: No), the process proceeds to step S29.

In this embodiment, the control unit 80 detects the thickness of the fed document, and if it determines that it is less than a predetermined thickness, it transports the document in normal mode, and if it determines that it is equal to or greater than the predetermined thickness, it transports the document in passport mode as the transport mode. In passport mode, when the rear end ST of the holder 100 passes through the separation nip N1 and the holder 100 is clamped by the discharge nip N2, the drive unit 3 is stopped and the drive to the feed roller 11 is cut off.

Therefore, until the separation nip N1 passes the rear end ST of the holder 100, which is particularly thick and has a large transport load, the paper feed roller 11 is driven by the drive unit 3, and the paper feed roller 11 assists the second transport unit 20 and the third transport unit 30 in transporting the holder 100. This suppresses slippage between the second transport unit 20 and the third transport unit 30 and the holder 100, and loss of synchronism of the drive unit 4, reducing transport problems such as jamming of the holder 100.

Furthermore, when the rear end ST of the holder 100 passes the media detection sensor 60, the driving of the drive unit 3 is resumed and the subsequent document (e.g., another holder) is fed. In this way, in the passport mode, the drive unit 3 does not continue to be driven, but there is a timing at which the drive unit 3 stops, which suppresses the temperature rise of the drive unit 3, ensures that the specified motor characteristics are obtained, and extends the life of the drive unit 3. Therefore, it is possible to provide a sheet conveying device and image reading device A that suppresses the temperature rise of the drive unit 3 and enables stable sheet conveyance.

Third Embodiment
A third embodiment of the present invention will be described below. This embodiment has the same configuration as the first embodiment, and only the differences will be described below.

In the first embodiment, the invention was described as being aimed at obtaining sufficient transport force when transporting thick booklet-like documents such as passports, and transporting the document stably without stretching or blurring the image. In contrast, the present embodiment is an invention for a situation in which, in a document loading state in which the leading edge of the document placed on the loading platform 1 abuts against the document stopper 15, the document stopper 15 cannot be removed from the transport path due to the weight of the document loaded on the loading platform 1.

Conventionally, in sheet feeding devices that feed sheets one by one from a loading platform, a stopper such as document stopper 15 is provided to stop the sheet stack so that the sheet stack is not pushed further back than the loading platform and set. In such sheet feeding devices, the stopper is designed to retract as soon as the sheet feeding operation starts, but there are cases where the stopper does not retract and feeding operation becomes impossible, particularly when the sheet stack is pushed in too hard or the edge of the sheet stack is rough.

For this reason, a technology has been proposed that, if the paper feed operation is not possible, stops the rotation of the paper feed roller 11 in the paper feed section or rotates it at a slower speed, thereby reducing the load on the stopper and allowing the sheet feed operation to continue.

However, although the load on the stopper is reduced by stopping the rotation of the paper feed roller 11 or rotating it at a slow speed, depending on the type and condition of the sheet, the load may not be reduced sufficiently, and paper feeding problems may occur because the stopper does not retract.

In contrast, in this embodiment,
A conveying path formed between an upper unit and a lower unit disposed opposite each other;
a sheet feed roller that feeds a sheet at a portion that is partially exposed to the conveyance path from an upper surface of the lower unit;
a stopper that stops the sheet stack from entering the conveying path by abutting a leading end of the sheet stack when the stopper is in a closed state moved in a direction intersecting with an exposed surface of the sheet feed roller;
a drive unit that drives at least the paper feed roller and the stopper;
a detection means for detecting that a sheet has passed the paper feed roller;
A sheet feeding device having a control means for executing a retry control for stopping the sheet feeding and starting the sheet feeding again when a time from when the sheet feeding roller starts feeding the sheet to when the sheet is detected by the detection means exceeds a predetermined time,
The control means
a retry count measuring means for measuring the number of retries performed in the retry control;
The retry control method is characterized in that the time for stopping paper feeding under the retry control is changed based on the number of retries measured by the retry number measuring means.

With this configuration, by controlling the time that the feed roller stops rotating, the stopper, which is biased in the retracting direction by a spring, can be made to move more easily in the retracting direction. As a result, the load on the stopper can be sufficiently reduced, making it possible to provide a sheet feeding device that reduces the number of times that paper feed failures occur and eliminates the need for unnecessary jam processing.

The image reading device A3 according to this embodiment will be described in detail below. As shown in FIG. 18, the first transport section 10 is composed of an upper unit 103 constituting the upper transport path and a lower unit 104 constituting the lower transport path, which are arranged opposite each other. A transport path RT for the original S is formed in the space (gap) between the upper unit 103 and the lower unit 104. The transport path RT is inclined from the upper right to the lower left in the figure.

The upper unit 103 has a separation roller 12 arranged opposite the paper feed roller 11, a document stopper 15, and a pickup roller 8 and a pickup arm 9, which are exemplified as a pickup unit. The lower unit 104 has a loading platform 1 and a paper feed roller 11.

The document stopper 15 has the function of opening and closing the passage of the first transport section 10, and when closed, it stops the leading edge of the document S placed on the placement table 1 just before it enters the pressing surface (separation nip N1) of the feed roller 11 and separation roller 12. The pickup roller 8 is rotatably supported at the leading end of the pickup arm 9 and is supported so as to be able to retract into and out of the document S. The pickup roller 8 presses the document S, which has been released from the restraint by the document stopper 15, from the top layer toward the feed roller 11.

As shown in FIG. 19, the lower unit 104 is provided with a drive unit 3 such as a motor. The drive unit 3 drives and rotates the paper feed roller 11 in the sheet transport direction D1 via the timing belt 6 and gear 14d. At the same time, the drive unit 3 drives and rotates the separation roller 12 via the timing belt 6 and gear train 15f to 15j. Here, the direction in which the paper feed roller 11 is driven and rotated in the sheet transport direction D1 is called forward rotation, and the opposite direction is called reverse rotation.

Figure 20 shows a cross section different from that of Figure 19. As shown in Figure 20, the lower unit 104 is further provided with a drive unit 4 such as a motor. The drive unit 4 drives and rotates the drive rollers 21 and 31 in the sheet conveying direction D1 via a timing belt 16 and gears 17a and 17b. Here, the direction in which the drive unit 4 is driven and rotated in the sheet conveying direction D1 is called forward rotation, and the opposite direction is called reverse rotation. At the same time, power is transmitted to the pickup drive unit 106 via gears 17a and 18. As shown in Figure 21, the pickup drive unit 106 includes a gear 19 that meshes with the gear 18, a one-way clutch 23, a shaft 24 extending from the one-way clutch 23, and a cam member 25 attached to the end of the shaft 24.

As shown in FIG. 22, when the drive section 4 is rotated in the reverse direction and the gear 19 of the pickup drive unit 106 rotates in the direction of the arrow w1 via the gear 18, the one-way clutch 23 is locked and rotates the cam member 25 via the shaft 24. Then, the document stopper 15 and the pickup arm 9 move in the opposite directions to the arrows w2 and w3 due to the action of the cam member 25. Then, the document stopper 15 closes the transport path RT (closed state), and the pickup arm 9 retracts from the paper feed roller 11 (retracted state).

On the other hand, when the drive section 4 is rotated forward and the gear 19 of the pickup drive unit 106 rotates in the direction opposite to the arrow w1 via the gear 18, the one-way clutch 23 is unlocked and power is not transmitted from the shaft 24 to the cam member 25. As a result, the document stopper 15 and the pickup arm 9 move in the directions of the arrows w2 and w3, respectively, due to the biasing forces of the springs 26 and 27. Then, as shown in FIG. 20, the document stopper 15 opens the passage of the first transport section 10 (open state), and the pickup arm 9 is pressed against the paper feed roller 11 (pressed state).

In this embodiment, the actuator 86 in FIG. 11 also includes the pickup arm 9 and the like in addition to the above.

[Operation flow of the paper feed mechanism]
Next, the paper feeding operation of the image reading device A3 according to this embodiment will be described with reference to FIGS.

Figure 23 is a flowchart showing the paper feeding operation of the image reading device A3 according to this embodiment. In the standby state before feeding of the original S shown in Figure 19, the original stopper 15 closes the transport path RT (closed state), and the pickup arm 9 is held in a state retracted from the paper feed roller 11. The user sets the original S on the placement table 1 so that the leading edge of the original S abuts against the original stopper 15.

Now, referring to FIG. 23, the paper feeding operation from the state shown in FIG. 19 will be described. In step S101, a request to start the paper feeding operation is detected from the operation unit 83 or the communication unit 84. In step S102, the control unit 80 detects the presence or absence of the original S loaded on the placement table 1 based on the output of the original detection sensor 90.

If the document S is not detected by the document detection sensor 90, in step S103 the control unit 80 causes the display unit 94 of the display panel 93 to display a message informing the user that the document S is not placed. This notifies the user of a paper feed error, and ends the process without performing a paper feed operation. If the document S is detected by the document detection sensor 90, in step S105 the control unit 80 detects that an arbitrary number of times has been set in the retry setting counter.

If the control unit 80 detects in step S105 that no arbitrary number has been set in the retry setting counter or that the counter is set to 0, it performs the feeding operation without retry feeding in steps S201 to S206. That is, in step S201, the feed roller 11 is rotated to start feeding the original S. When the original stopper 15 opens the passage of the first transport unit 10 (open state), in step S202, the media detection sensor 50, which is located downstream in the sheet transport direction from the original detection sensor 90, detects the leading edge of the original S. Then, in step S203, the rotation of the feed roller 11 is stopped, and in step S204, it is determined that the feeding operation has ended normally. On the other hand, if the document stopper 15 does not change from a closed state (closed state) to an open state (open state) in which the transport path RT is closed, in step S202, the document detection sensor 90 does not detect the leading edge of the document S, and in step S205, when the delay jam detection timer ends, in step S206, the control unit 80 causes the display unit 94 of the display panel 93 to display a message informing the user of the paper feed error, and ends the paper feed operation.

If it is detected in step S105 that an arbitrary number has been set in the retry setting counter, the number of paper feed executions n is set to 0 in step S106.

The retry setting counter is a counter that stores a preset value for the number of times to perform a retry operation. The retry setting counter can be set to two times or any value greater than this, taking into account the condition of the document S.

In step S107, the control unit 80 starts the paper feed operation. At this time, the control unit 80 rotates the drive unit 3 in the normal direction to rotate the paper feed roller 11, or at the same time, starts the process of rotating the drive unit 4 in the normal direction to rotate the drive rollers 21 and 31. Note that when the drive unit 3 is driven, the leading edge of the document S hits the document stopper 15, correcting the reverse handling state of the documents on the placement table 1 and making it easier to feed the bottom document first.

In step S108, a timer is started to detect a delay jam. When the forward rotation process of the drive units 3 and 4 starts in step S107, the feed roller 11 rotates in step S109 and the original S is fed. As shown in FIG. 20, the original stopper 15 opens the path of the first transport unit 10 (open state). At this time, if the original S is pushed in strongly or if the edge surface of the original S is rough, the original stopper 15 may be unable to open the transport path due to forces such as friction caused by the original S and may remain in a state where the transport path RT is closed (closed state).

When the document stopper 15 opens the passage of the first transport section 10 (open state), in step S110, the media detection sensor 50, which is located downstream in the sheet transport direction from the document detection sensor 90, detects the leading edge of the document S. Then, in step S111, the rotation of the paper feed roller 11 is stopped, and in step S112, it is determined that the paper feed operation has ended normally.

If the document stopper 15 does not change from a closed state (closed state) to an open state (open state) in which the transport path RT is closed, the leading edge of the document S is not detected by the document detection sensor 90 in step S110, and the delay jam detection timer ends in step S113. Detection of the document S in step S110 is continued until the delay detection timer ends in step S113. When the delay jam detection timer ends in step S113, the number of times paper feeding is performed n is incremented in step S114, and the number of times paper feeding is performed is counted.

In step S115, the retry setting counter is compared with the number of times the paper feed is performed. If the result of step S115 is that the number of times the paper feed is performed n is equal to or less than the value of the retry setting counter, in step S118, the paper feed stop time is set based on the number of times the paper feed is performed.

The paper feed stop time is the time during which the paper feed operation is temporarily stopped before restarting the paper feed operation if the paper feed operation does not end normally. During the paper feed stop time, the control unit 80 stops the drive unit 3 and stops the forward rotation of the paper feed roller 11.

In step S119, paper feeding is stopped for the time set in step S118. When the document stopper 15 does not move from the state in which the transport path RT is closed (closed state), if the paper feed roller 11 rotates forward, the document S will attempt to proceed in the sheet transport direction D1, placing a load on the document stopper 15. As a result, it becomes difficult for the document stopper 15 to move to a state in which the transport path RT is open (open state). When the forward rotation of the paper feed roller 11 is stopped, the load on the document stopper 15 is reduced, making it easier to move the transport path RT to an open state (open state). At this point, the document stopper 15 is no longer biased toward the closed state by the drive unit 4, so it is in a state in which it is easy to move to the open state.

The paper feed stop time in step S119 is set to be longer the more times paper feed is performed. By making the paper feed stop time longer, the time it takes for the document stopper 15 to retract can be set longer, which prevents the delay jam detection timer from ending while the document stopper 15 is retracting, preventing it from being determined that a delay jam has occurred.

After step S119, the paper feed operation performed from step S107 to step S114 is performed again. The paper feed operation from step S107 to step S114 is repeated, and when the condition of the paper feed execution count counter≦retry setting counter is no longer satisfied in step S115, the control unit 80 determines that a delay jam has occurred. Then, in step S116, the control unit 80 causes the display unit 94 of the display panel 93 to display a message informing the user of the paper feed error, and ends the paper feed operation.

In step S119, the load on the document stopper 15 is reduced by stopping the forward rotation of the paper feed roller 11, but the forward rotation of the paper feed roller 11 may be reversed. By reversing the paper feed roller 11, the load on the document stopper 15 can be reduced in a short time, so that the transport path RT can be opened (open state) in a shorter time than if the paper feed roller 11 were stopped.

As described above, according to this embodiment, the number of times paper feeding is performed is counted, and the more the number of times paper feeding is performed, the longer the paper feeding stop time becomes, so the probability of successfully retracting the document stopper 15 increases with repetition. Compared to the conventional method, the number of times paper feeding failures occur is reduced, eliminating the need for unnecessary jam handling and improving usability.

In the third embodiment, the drive units 3 and 4 are used, but a single drive unit may be used. In that case, the movement of the drive unit, the feed roller 11, and the document stopper 15 are linked.

<Other embodiments>
In the first embodiment, the drive unit 3 is stopped at the timing when the binding margin portion Sa passes through the discharge nip N2, but this is not limited to this. For example, if the holder 100 is sandwiched by the discharge nip N2, the drive unit 3 may be stopped a predetermined time after the binding margin portion Sa passes through the discharge nip N2.

In the second embodiment, the drive unit 3 is stopped when the rear end ST of the holder 100 passes through the separation nip N1, but this is not limited to the above. For example, if the holder 100 is clamped by the discharge nip N2, the drive unit 3 may be stopped a predetermined time after the rear end ST passes through the separation nip N1.

In addition, in all of the above-mentioned configurations, the document is fed by the feed roller 11, but this is not limited to the above. For example, a pickup roller may be disposed upstream of the feed roller 11 in the sheet transport direction D1, and the sheet may be fed by the pickup roller. In addition, one or both of the feed roller 11 and the separation roller 12 are not limited to rollers, and may be other rotating bodies such as belts.

In addition, in any of the above-described embodiments, the sheet conveying speed in the second conveying section 20 and the third conveying section 30 is set to the same conveying speed V1 as the sheet conveying speed in the separation nip N1, but is not limited to this. For example, the sheet conveying speed in the second conveying section 20 and the third conveying section 30 may be set to a conveying speed faster than the conveying speed V1.

In the first and second embodiments, the drive from the drive unit 3 to the paper feed roller 11 is cut off by stopping the drive unit 3, but this is not limited to the above. For example, while the drive unit 3 is driven, the drive to the paper feed roller 11 may be cut off by a transmission unit 5 consisting of an electromagnetic clutch or the like. Also, instead of the two motors of the drive unit 3 and the drive unit 4, the first conveying unit 10, the second conveying unit 20, and the third conveying unit 30 may be driven by one motor.

In addition, although the above embodiments have been described using an image reading device, the present invention is not limited to this. For example, the present invention can also be applied to an inkjet or electrophotographic image forming device, or a feed deck or optional feeder connected to an image forming device.

In addition, in all of the above-described embodiments, the timing of driving or stopping the drive unit 3 is controlled based on the timing when the leading or trailing edge of the document passes the media detection sensor 60, but this is not limiting. For example, the timing of driving or stopping the drive unit 3 may be controlled based on an image reading start instruction (feed start instruction) from an external computer, rather than based on the detection result of the media detection sensor 60.

The present invention can also be realized by supplying a program that realizes one or more of the functions of the above-mentioned embodiments to a system or device via a network or storage medium, and having one or more processors in the computer of the system or device read and execute the program. It can also be realized by a circuit (e.g., an ASIC) that realizes one or more functions.

1: Loading section (loading table) / 3: Driving source (driving section) / 11: Feeding rotor (feed roller) / 12: Separation rotor (separation roller) / 30: Discharge rotor pair (third conveying section) / 60: Detection section (media detection sensor) / 70: Reading section (reading unit) / 83: Operation section / 100: Holder / 123: Thickness detection section (thickness detection sensor) / 130: Acquisition section (short-range wireless reader unit) / A: Image reading device / D1: Sheet conveying direction / N1: Separation nip / N2: Discharge nip / Sa: Binding margin section / V1: Conveying speed

Claims (14)

a loading section on which sheets are loaded;
a feeding rotor that feeds the sheets stacked in the stacking section;
a separation rotor that forms a separation nip together with the feeding rotor and separates the sheets one by one at the separation nip;
a pair of discharge rotors disposed downstream of the separation nip in a sheet conveying direction and having a discharge nip for discharging the sheet fed by the feed rotor;
A drive source capable of driving the feeding rotor;
a conveying mode in which, when conveying a booklet-like sheet having a binding margin in an open state, the sheet stacked on the stacking section is fed by driving the feeding rotating body, and the driving force from the driving source to the feeding rotating body is cut off in a state in which the binding margin of the sheet passes through the discharge nip of the pair of discharge rotating bodies and the sheet is sandwiched by the discharge nip;
A sheet conveying device comprising: a loading section on which sheets are loaded;
a feeding rotor that feeds the sheets stacked in the stacking section;
a separation rotor that forms a separation nip together with the feeding rotor and separates the sheets one by one at the separation nip;
a pair of discharge rotors disposed downstream of the separation nip in a sheet conveying direction and having a discharge nip for discharging the sheet fed by the feed rotor;
a drive source capable of driving the feeding rotor,
a conveying mode in which, when conveying a booklet-like sheet having a binding margin in an open state, the sheet stacked on the stacking section is fed by driving the feeding rotating body, and the driving force from the driving source to the feeding rotating body is cut off in a state in which the trailing end of the sheet passes through the separation nip and the sheet is sandwiched by the discharge nip;
A sheet conveying device comprising: A detection unit that detects the sheet fed by the feeding rotary body is further provided,
determining a timing to cut off the driving force from the driving source to the feeding rotator based on the detection of the leading edge of the sheet by the detection unit in the conveying mode;
3. The sheet conveying device according to claim 1, wherein the sheet conveying device is a sheet conveying device. in the conveying mode, the driving source cuts off the driving force to the feeding rotating body after a predetermined time has elapsed since the detection unit detected the leading edge of the sheet fed by the feeding rotating body based on the sheet conveying speed of the pair of discharge rotating bodies;
4. The sheet transport device according to claim 3. in the conveying mode, a driving force is transmitted from the driving source to the feeding rotator based on the detection of the trailing end of the sheet by the detection unit;
5. The sheet transport device according to claim 3, wherein the sheet transport device is a sheet conveying device. In the conveying mode, the pair of discharge rotors conveys the sheet at the same speed as the conveying speed of the sheet in the separation nip.
6. The sheet transport device according to claim 1, wherein the sheet transport device is a sheet conveying device. In the transport mode, a booklet-shaped passport containing an IC chip and accommodated in a holder can be transported.
7. The sheet transport device according to claim 1, wherein the sheet transport device is a sheet conveying device. An acquisition unit capable of acquiring nationality information from the IC chip of the passport,
In the conveying mode, a length of the passport in the sheet conveying direction is obtained from the nationality information obtained by the obtaining unit, and a timing for cutting off the drive from the drive source to the feeding rotator is determined.
8. The sheet transport device according to claim 7. Further comprising an operation unit for receiving an operation from a user,
in the conveying mode, a length of the passport in the sheet conveying direction is obtained from a user's operation on the operation unit, and a timing for cutting off the drive from the drive source to the feeding rotator is determined.
8. The sheet transport device according to claim 7. Further, a thickness detection unit is provided for detecting the thickness of the sheet being conveyed,
When the thickness of the sheet detected by the thickness detection unit is equal to or greater than a predetermined thickness, the conveying mode is executed.
10. The sheet transport device according to claim 1, wherein the sheet transport device is a sheet conveying device. a loading section on which sheets are loaded;
a feeding rotor that feeds the sheets stacked in the stacking section;
a separation rotor that forms a separation nip together with the feeding rotor and separates the sheets one by one at the separation nip;
a pair of discharge rotors disposed downstream of the separation nip in a sheet conveying direction and having a discharge nip for discharging the sheet fed by the feed rotor;
A drive source capable of driving the feeding rotor;
a conveying mode in which, when conveying a sheet having a first portion having a first thickness and a second portion having a second thickness thicker than the first thickness at different positions in the sheet conveying direction, the sheet stacked on the stacking section is fed by driving the feeding rotor, and the drive from the drive source to the feeding rotor is cut off when the second portion of the sheet passes through the discharge nip of the pair of discharge rotors and the sheet is sandwiched by the discharge nip;
A sheet conveying device comprising: the drive source is a first drive source,
The apparatus further includes a second drive source capable of driving the pair of discharge rotors,
In the transport mode, the first driving source is stopped, whereby the driving of the feeding rotator from the first driving source is cut off.
12. The sheet transport device according to claim 1, wherein the sheet transport device is a sheet conveying device. the drive source is capable of driving the feeding rotor and the pair of discharging rotors,
a clutch capable of disconnecting the drive source from the feed rotor in the transport mode,
12. The sheet transport device according to claim 1, wherein the sheet transport device is a sheet conveying device. A sheet conveying device according to any one of claims 1 to 13 ,
a reading unit that reads an image of a sheet conveyed by the sheet conveying device,
1. An image reading apparatus comprising:

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