JP5718621B2 - Sheet conveying apparatus and information reading apparatus - Google Patents

Description

  The present invention relates to a sheet conveying technique applied to, for example, a copying machine, a scanner, a printer, and the like.

  2. Description of the Related Art Copiers, scanners, printers, and the like are known that include a sheet feeding mechanism that conveys a plurality of stacked sheets one by one. For example, in a scanner, a bundle of documents such as a check and a check is placed on a document table, and the image is read one by one by a sheet feeding mechanism. As such a scanner, an image reading apparatus that reads an image of a document while separating and transporting the documents one by one is known (for example, Patent Document 1).

JP 2008-270954 A

  An apparatus that continuously reads a bundle of documents is required to have a large number of documents processed per unit time, that is, high-speed conveyance and high-speed reading. For this reason, generally, as in the image reading device disclosed in Patent Document 1, a method of continuously conveying originals while separating them one by one is widely adopted. However, in such an apparatus that continuously conveys documents one by one while separating them one by one, it is difficult to control the document interval between the preceding document and the succeeding document to be short, which hinders improvement in the number of documents processed per unit time. It has become.

  Note that the above-described problem does not occur only in the document reading apparatus, and similarly occurs in, for example, a sheet conveying apparatus that conveys sheets while sequentially feeding them one by one in the sheet conveying path.

  The present invention provides a technique for improving sheet conveyance efficiency.

According to the present invention,
A feeding means for sequentially feeding sheets one by one into the sheet conveying path;
A conveying unit that is provided on the downstream side of the feeding unit and conveys the sheet fed by the feeding unit toward the downstream side;
A detecting means provided between the feeding means and the conveying means for detecting the arrival of the sheet fed from the feeding means for each sheet ;
A double feed detecting means provided between the feeding means and the conveying means for detecting double feed of sheets fed from the feeding means;
Control means for controlling the feeding means,
The control means includes
And stopping or deceleration control of the feeding operation, and restarting or re-acceleration control after executing the stop or deceleration control, the repetitive control to the preceding detection result based rather the feeding means of said detecting means Provided is a sheet conveying apparatus characterized in that a sheet interval between a sheet and a succeeding sheet is created, and the restart or reacceleration control is executed on condition that there is no double feed detection by the double feed detection means. Is done.

Moreover, according to the present invention,
A feeding means for sequentially feeding sheets one by one into the sheet conveying path;
A conveying unit that is provided on the downstream side of the feeding unit and conveys the sheet fed by the feeding unit toward the downstream side;
A detecting means provided between the feeding means and the conveying means for detecting the arrival of the sheet fed from the feeding means for each sheet ;
A double feed detecting means provided between the feeding means and the conveying means for detecting double feed of sheets fed from the feeding means;
Control means for controlling the feeding means and the conveying means,
Wherein, while the speed control to be faster than the speed feed the sheet conveying speed of said feeding means by said conveying means, feeding at based rather said feeding means on a detection result of said detecting means and control of the stop or deceleration operation, the a stop or re-start or re-acceleration control after executing the deceleration control, and repeatedly controlling said control restarts or re-acceleration, the heavy feed detection by the double feed detecting means A sheet conveying apparatus is provided that is executed on the condition that there is no sheet.

Furthermore, according to the present invention, there is provided an information reading device comprising information reading means for reading information on a sheet conveyed by the sheet conveying device .

  According to the present invention, sheet conveyance efficiency can be improved.

1 is a schematic diagram of an image reading apparatus according to an embodiment of the present invention. The flowchart of the process in connection with the conveyance control of a 1st conveyance part. The figure which shows the example of conveyance. The figure which shows the example of a conventional conveyance. (A) thru | or (C) is a figure which shows the other example of the position detection sensor of an upstream. Schematic of an image reading apparatus according to another embodiment of the present invention.

<First Embodiment>
FIG. 1 is a schematic view of an image reading apparatus A according to an embodiment of the present invention. In this embodiment, an example in which the sheet conveying apparatus of the present invention is applied to an image reading apparatus is shown. However, information to be read is not limited to an image, and can be applied to an information reading apparatus that reads various kinds of information. The sheet conveying apparatus of the present invention can also be applied to other types of apparatuses such as a printer. In the following description, the upstream side or the downstream side in the sheet conveyance path is based on the sheet conveyance direction.

<Device configuration>
The image reading apparatus A is an apparatus that conveys a plurality of sheets S stacked on the document table 1 one by one in the apparatus on a path (sheet conveyance path) RT, reads the image, and discharges the image to the discharge tray 2. is there. The sheet S as a reading document is, for example, OA paper, a check, a check, or the like.

  The first conveying unit 10 as a feeding unit that feeds the sheet to the path RT includes a feeding roller 11 and a separation roller 12 and sequentially conveys the sheets S on the document table 1 one by one. A driving force is transmitted to the feed roller 11 from the driving unit 3 such as a motor via the transmission unit 5 and is driven to rotate in the direction of the arrow. The transmission unit 5 is, for example, an electromagnetic clutch, and interrupts the driving force from the driving unit 3 to the feed roller 11.

  The transmission unit 5 is in a state where the driving force is transmitted in a normal state, and interrupts the driving force in the case of reverse feeding of the sheet S described later. When the transmission of the driving force is interrupted by the transmission unit 5, the feed roller 11 is in a freely rotatable state.

  The separation roller 12 is a roller for separating the sheets S one by one, and is in pressure contact with the feed roller 11 at a constant pressure. In order to ensure this pressure contact state, it is desirable that the separation roller 12 is provided so as to be swingable and is urged to the feed roller 11. The separation roller 12 is driven to rotate in the direction indicated by the solid line arrow when the driving force is transmitted from the driving unit 3 through the torque limiter 12a. Since the driving force transmission is restricted by the torque limiter 12a, the separation roller 12 rotates in a direction (indicated by a broken arrow) along with the feed roller 11 when contacting the feed roller 11. As a result, when a plurality of sheets S are conveyed to the pressure contact portion between the feed roller 11 and the separation roller 12, the sheet S is blocked so that two or more sheets S are not conveyed downstream except for one sheet.

  In the present embodiment, the separation roller 12 and the feed roller 11 constitute the separation mechanism. However, such a separation mechanism is not necessarily provided, and the sheet S is sequentially fed to the path RT one by one. Any mechanism may be used.

  The second conveyance unit 20 as a conveyance unit includes a driving roller 21 and a driven roller 22, and is provided on the downstream side of the first conveyance unit 10 and also conveys the sheet S conveyed from the first conveyance unit 10. Transport downstream. Driving force is transmitted to the driving roller 21 from the driving unit 4 such as a motor, and the driving roller 21 is rotationally driven in the direction of the arrow. The driven roller 22 is brought into pressure contact with the driving roller 21 at a constant pressure, and rotates with the driving roller 21.

  The third conveyance unit 30 includes a driving roller 31 and a driven roller 32, and is provided on the downstream side of the second conveyance unit 10 and conveys the sheet S conveyed from the second conveyance unit 20 to the discharge tray 2. To do. A driving force is transmitted to the driving roller 31 from the driving unit 4 such as a motor, and the driving roller 31 is rotationally driven in the arrow direction. The driven roller 32 is brought into pressure contact with the driving roller 31 at a constant pressure, and is driven by the driving roller 31.

  In the present embodiment, the second conveyance unit 20 and the third conveyance unit 30 convey the sheet S at a constant speed for reading by the image reading unit 70. By always setting the conveyance speed to be equal to or higher than the conveyance speed of the first conveyance unit 10, it is possible to reliably avoid a situation in which the subsequent sheet catches up with the preceding sheet. Therefore, in the present embodiment, the speed of the sheet S transported by the second transport unit 20 and the third transport unit 30 is controlled so as to be faster than the transport speed of the sheet S by the first transport unit 10.

  Even when the conveyance speed of the sheet S by the second conveyance unit 20 and the third conveyance unit 30 and the conveyance speed of the sheet S by the first conveyance unit 10 are set to the same condition, the feeding start timing of the subsequent sheet S is set. It is also possible to form a minimum sheet interval between the preceding sheet S and the succeeding sheet S by intermittently shifting.

  The double feed detection sensor 40 is provided between the first transport unit 10 and the second transport unit 20, and when the sheets S are in close contact with each other due to static electricity or the like and passes through the first transport unit 10 (multiple feed). This is an example of a detection sensor (means for detecting the behavior and state of the sheet) for detecting this. Various sensors can be used as the double feed detection sensor 40, but in the case of the present embodiment, an ultrasonic sensor is provided, which includes a transmission unit 41 and a reception unit 42, and the sheet S is double fed. Double feed is detected based on the principle that the attenuation amount of the ultrasonic wave passing through the sheet S is different between the case where the sheet is conveyed one by one.

  The position detection sensor 50 is an example as an upstream detection sensor (means for detecting the behavior and state of a sheet) disposed upstream of the second transport unit 20 and downstream of the first transport unit 10. The position of the sheet S conveyed by the first conveying unit 10, specifically, whether or not the end of the sheet has reached or passed through the detection position of the position detection sensor 50 is detected. Various sensors can be used as the position detection sensor 50. In the case of the present embodiment, the position detection sensor 50 is an optical sensor, and includes a light emitting unit 51 and a light receiving unit 52. The sheet S is detected on the principle that the amount of received light) changes.

  In the case of the present embodiment, the position detection sensor 50 is configured such that when the leading edge of the sheet S is detected by the position detection sensor 50, the sheet S has reached a position where the double feed detection sensor 40 can detect double feed. In the vicinity of the double feed detection sensor 40, it is provided on the downstream side thereof. The position detection sensor 50 is not limited to the above-described optical sensor, and for example, a sensor (such as an image sensor) that can detect the end of the sheet S may be used.

  The position detection sensor 60 is an example of a downstream detection sensor disposed upstream of the image reading unit 70 and downstream of the second conveyance unit 20, and the sheet S conveyed by the second conveyance unit 20. The position of is detected. Various sensors can be used as the position detection sensor 60. In the case of the present embodiment, the position detection sensor 60 is an optical sensor similar to the position detection sensor 50. Alternatively, the sheet S is detected based on the principle that the received light intensity (received light amount) changes due to passage.

  The image reading units 70 and 70 are, for example, optically scanned, converted into electrical signals and read as image data, and include a light source such as an LED, an image sensor, a lens array, and the like. In the present embodiment, one image reading unit 70 is disposed on each side of the path RT, and reads the front and back surfaces of the sheet S. However, only one side of the route RT may be arranged to read only one side of the sheet S.

  The control unit 6 is an electric circuit including a processing unit such as a CPU, a storage unit such as a ROM and a RAM, and an interface unit that interfaces the processing unit and an external device, and includes a double feed detection sensor 40 and a position detection sensor 60. , 70 and the image data read by the image reading unit 70 are acquired from these. Further, the drive units 3 and 4 and the transmission unit 5 are controlled.

<Control example>
A basic operation of the image reading apparatus A will be described. When the control unit 6 receives a document reading start instruction from, for example, an external personal computer connected to the image reading apparatus A, the control unit 6 starts driving the first to third transport units 10 to 30. A plurality of sheets S stacked on the document table 1 are conveyed one by one from the lowermost sheet S.

  In the middle of conveyance, the sheet S is determined by the double-feed detection sensor 40 to determine whether or not double-feed is present. If it is determined that there is no double-feed, the conveyance is continued. The control unit 6 starts reading an image of the sheet S conveyed by the second conveyance unit 20 by the image reading units 70 and 70 at a timing based on the detection result of the position detection sensor 60, and primarily reads the read image. Memorize and send to external PC sequentially. The sheet S on which the image has been read is discharged to the discharge tray 2 by the third transport unit 30, and the image reading process for the sheet S is completed.

  Next, specific processing related to the conveyance of the sheet S by the first conveyance unit 10 by the control unit 6 will be described with reference to FIG. FIG. 2 is a flowchart of processing related to the conveyance control of the first conveyance unit 10.

  When the control unit 6 receives a document reading start instruction from the external personal computer, the control unit 6 starts the processing of FIG. In S1, the drive unit 3 is driven to rotationally drive the feed roller 11 and the separation roller 12. The transmission unit 5 is in a driving force transmission state. As a result, the sheet S on the document table 1 is conveyed into the apparatus (path RT). In S2, it is determined whether the position detection sensor 50 on the upstream side of the route RT has detected the leading edge of the sheet S (whether the detection result has changed from non-detection to detection). If applicable, the process proceeds to S3. Wait until the sheet S is detected. Note that the connection between the image reading apparatus A and the external personal computer may be a USB connection method or a connection method via a network. In addition to the remote control of the image reading apparatus A from an external personal computer as in the present embodiment, for example, the image reading apparatus A is provided with a server function, a user interface control function, etc., and is directly operated by the image reading apparatus A. Then, the operation of the image reading apparatus A may be controlled based on the above, and the read image data may be output to a predetermined destination (such as a personal computer).

  In S3, the conveyance of the sheet by the first conveyance unit 10 is temporarily delayed so that the sheet does not reach the second conveyance unit 20 until the multi-feed determination is completed. In this embodiment, the conveyance is temporarily stopped by stopping the driving of the drive unit 3. However, the conveyance may be delayed by reducing the conveyance speed. In S4, the detection result of the double feed detection sensor 40 is acquired and it is determined whether double feed is occurring. If it is determined that double feeding has occurred, the process proceeds to S7. If it is determined that double feeding has not occurred, the process proceeds to S6. As described above, in the present embodiment, the double feed detection by the double feed detection sensor 40 is executed based on the detection result of the sheet S.

  In S6, for example, the conveyance by the first conveyance unit 10 that has been delayed in S3 is restored. That is, the feeding of the sheet S that has been paused is resumed. Note that restarting the feeding of the sheet S means that the control unit 6 restarts or restarts after executing the stop or deceleration control of the feeding operation in the first conveying unit 10 based on the detection result of the position detection sensor 50. Means acceleration control. Here, the control unit 6 restarting or reaccelerating the feeding operation means that the feeding operation is resumed at a predetermined speed from a state where the feeding operation is stopped or decelerated. In addition, when the example which delays by decelerating a conveyance speed (feeding speed) is employ | adopted, a conveyance speed (feeding speed) will be returned.

  In S7, since double feeding has occurred, processing to reversely feed the sheet S to the document table 1 is performed. Here, the drive unit 3 is driven after the transmission unit 5 blocks power transmission from the drive unit 3 to the feed roller 11. Then, the separation roller 12 rotates in the direction indicated by the solid line in FIG. 1, the feed roller 11 is brought into the state of being accompanied by the separation roller 12, and the sheet S is returned to the document table 1.

  In the present embodiment, the drive unit 3 is shared by the feed roller 11 and the separation roller 12, but may be provided separately. In this case, the transmission part 5 becomes unnecessary. Further, as a process after the process of S7 is performed for a predetermined time, as shown by a broken line, the process may return to S1 and start reading again, or the conveyance may be stopped and an error warning or the like may be performed. .

  In S8, it is determined whether an end condition is satisfied. Examples of the end condition include a case where a reading end instruction is received from an external personal computer, a case where all the sheets S on the platen 1 are read (for example, a case where the position detection sensor 50 is not in a detection state for a certain period), and the like. If the end condition is not satisfied, the process returns to S2. If the end condition is satisfied, the conveyance is stopped and one unit of processing is ended.

  In the present embodiment, the sheet S does not reach the second transport unit 20 until the double-feed determination of the sheet S is completed by the processes from S3 to S6. For this reason, when the double feed occurs and the reverse feed of S7 is performed, a situation in which the second conveying unit 20 sandwiches the sheet S is avoided, and the discharge of the double feed sheet S becomes easy. Since the control for preventing the sheet S from reaching the second transport unit 20 is to temporarily delay the transport by the first transport unit 10, the transport efficiency is improved as compared with the case of transporting at a constant low speed. Enhanced.

  Further, in controlling the first conveying unit 10, since the conveyance stop / restart control is not performed based on the detection result of the position detection sensor 60 on the downstream side, the conveyance efficiency can be improved when the sheet S is read continuously. This point will be described with reference to FIGS. First, the conventional method of FIG. 4 will be described as a comparative example. In the case of the conventional method, there is no configuration corresponding to the upstream position detection sensor 50, and the conveyance of the subsequent sheet S is started after the downstream position detection sensor 60 confirms the passage of the preceding sheet S.

  A state ST11 in FIG. 4 shows a state in which the sheet S is being conveyed from the document table 1 by the first conveying unit 10, and the leading end of the sheet S is detected by the position detection sensor 60 as shown in the state ST12. Until it is detected, the conveyance of the first conveyance unit 10 is stopped.

  As shown in state ST13, when the trailing edge of the sheet S is detected by the conveyance of the sheet S by the second and third conveyance units 20 and 30, the document table 1 is detected by the first conveyance unit 10 as shown in state ST14. Then, the conveyance of the next sheet S is started. The conveyance interval between the preceding sheet S and the subsequent sheet S is an interval d corresponding to the distance between the first conveyance unit 10 and the position detection sensor 60.

  The case of the present embodiment will be described with reference to FIG. In the example of FIG. 3, as in the flowchart of FIG. 2, the temporary delay of the conveyance by the first control unit 10 is the temporary stop of the conveyance.

  The state ST1 shows a state where the sheet S is being conveyed from the document table 1 by the first conveying unit 10, and this conveyance is continued until the position detection sensor 50 detects the leading edge of the sheet S as shown in the state ST2. If detected, the transport of the first transport unit 10 is temporarily stopped and the double feed determination is made. When the double feed determination is OK, the conveyance (feed) by the first control unit 10 is resumed and continues until the position detection sensor 50 detects the leading edge of the subsequent sheet S.

  For this reason, as shown in the state ST3, the succeeding sheet S can be transported with almost no spacing between the preceding sheet S and transport. State ST4 shows a state in which the leading edge of the succeeding sheet S is detected by the position detection sensor 50 and the conveyance operation by the first conveyance unit 10 is temporarily stopped. At this time, a conveyance interval is generated between the preceding sheet S and the succeeding sheet S. The state ST5 indicates a state in which the double sheet feeding determination for the succeeding sheet S is OK (no double sheet feeding) and the conveyance by the first control unit 10 is resumed. That is, in the states ST3 to ST4, the control unit 6 performs resumption (re-acceleration) control of the feeding operation by the first transport unit 10 based on the detection result of the position detection sensor 50, and from the first transport unit 10 Control is performed to transfer the sheet conveyance to the second conveyance unit 20.

  Note that such sheet conveyance delivery control may be performed based on the detection result of the double feed detection sensor 40 as well as the detection result of the position detection sensor 50. For example, when the multi-feed detection sensor 40 determines that there is no sheet multi-feed, the feeding of the first transport unit 10 is resumed or the sheet is transferred from the first transport unit 10 to the second transport unit 20. be able to.

  In any case, the sheet S can be continuously and efficiently conveyed downstream by controlling the sheet delivery timing. Such a sheet interval can be made with good reproducibility by repeatedly controlling the stop or deceleration of the feeding operation by the first conveying unit 10 and the subsequent reacceleration by the control unit 6.

  In the case where the sheet interval is appropriately adjusted, for example, when it is desired to ensure a sufficient sheet interval between the preceding sheet S and the succeeding sheet S, the control unit 6 performs the second conveying unit as in the present embodiment. It is desirable to control the sheet conveying speed at 20 faster than the feeding speed (conveying speed) by the first conveying unit 10. The position detection sensor 50 ensures that the end of the succeeding sheet S reaches the end reliably by completely separating the opposing ends of the two consecutive sheets by the difference in transport speed between the preceding sheet S and the succeeding sheet S. The sheet interval (for example, the minimum interval necessary for image reading, etc.) required thereafter can be detected with high accuracy and can be efficiently formed with good controllability by the resumption timing of the feeding operation by the first conveying unit 10.

  As described above, in this embodiment, the conveyance interval between the preceding sheet S and the subsequent sheet S is shorter than the interval d corresponding to the distance between the first conveyance unit 10 and the position detection sensor 60, and the sheet The conveyance efficiency can be improved.

  Further, in the present embodiment, the sheet multi-feed determination is performed in a state where the conveyance operation by the first conveyance unit 10 is temporarily stopped. For the double feed determination by the double feed detection sensor 40 such as an ultrasonic sensor, for example, a certain time (for example, about several tens of milliseconds) is preferable. On the other hand, if the sheet interval is narrowed or the conveyance speed is increased in order to increase the number of sheets processed, the detection accuracy of the sheet multi-feed determination may be lowered. For this reason, it is possible to ensure the detection accuracy of the multi-feed determination while improving the sheet transport efficiency by determining the double-feed of the sheet in a state where the feeding operation (transport operation) in the first transport unit 10 is temporarily stopped. It is also possible to make a multifeed determination in a state where the feeding operation in the first transport unit 10 is decelerated.

Second Embodiment
In the first embodiment, the position detection sensor 50 is disposed on the downstream side of the double feed detection sensor 40. However, the position may be any position between the first transport unit 10 and the second transport unit 20. . FIG. 5A shows an example in which the position detection sensor 50 is arranged upstream of the double feed detection sensor 40 as an example. In the case of this example, after the sheet S is detected by the position detection sensor 50 (the detection result is changed from non-detection to detection), after a certain amount of conveyance, the conveyance of the first conveyance unit 10 is delayed, thereby the sheet The conveyance delay can be performed after S reaches a position where the double feed detection sensor 40 can detect double feed. The determination of a certain amount of conveyance may be based on time, or when the drive unit 3 is a stepping motor, the number of drive pulses may be used as a reference.

  Moreover, in the said 1st Embodiment, although the optical sensor was illustrated as the position detection sensor 50, you may utilize another kind of sensor. FIG. 5B shows an example in which an encoder 53 is employed as a position detection sensor 50 ′ instead of the position detection sensor 50. A conveyance guide 54 is disposed facing the encoder 53, and the sheet S passes between the encoder 53 and the conveyance guide 54. The encoder 53 abuts on the sheet S and rotates by its movement, and outputs a signal proportional to the rotation amount. With this signal, it is possible to detect whether or not the sheet S has reached a position where the double feed detection sensor 40 can detect double feed.

  Further, when an ultrasonic sensor is employed as the double feed detection sensor 40, it may be used as the position detection sensor 50. FIG. 5C shows an example in which the double feed detection sensor 40 which is an ultrasonic sensor is also used as the position detection sensor 50. It is possible to detect that the sheet S has reached the position where the double feed determination can be made based on the attenuation amount of the reception signal in the ultrasonic sensor.

<Third Embodiment>
In the first embodiment, the sheet S on the document table 1 is sequentially conveyed from the lower side. However, the sheet S may be sequentially conveyed from the upper side. FIG. 6 is a schematic view of an image reading apparatus B according to another embodiment of the present invention. The same components as those of the image reading apparatus A in FIG. 1 are denoted by the same reference numerals and description thereof is omitted. Hereinafter, different components will be described. In FIG. 6, the drive units 3 and 4, the transmission unit 5, and the control unit 6 are not shown.

  In the image reading apparatus B, the first transport unit 10 includes a pickup roller 13. The pickup roller 13 is brought into contact with the sheet S stacked on the platen 1 and is driven to rotate in the direction of the arrow to guide the sheet S sequentially from the upper side to the feeding roller 11 and the separation roller 12. The pickup roller 14 is instructed by the arm unit 14 that is driven to rotate in the direction of the broken line arrow, and is normally brought into contact with the sheet S stacked on the document table 1 while the sheet S At the time of reverse feeding, the arm unit 14 is moved to a position spaced upward from the sheet S by the rotation of the arm unit 14 so that the reverse feeding of the sheet S by the separation roller 12 is not hindered.

  In the image reading apparatus B, three third conveyance units 30 are provided, and the sheet S is conveyed along a path RT curved in a semicircular shape and guided to the discharge tray 2.

  Such an image reading apparatus B can be controlled in the same manner as the image reading apparatus A. A combination of the second embodiment and this embodiment is also possible.

Claims (7)

A feeding means for sequentially feeding sheets one by one into the sheet conveying path;
A conveying unit that is provided on the downstream side of the feeding unit and conveys the sheet fed by the feeding unit toward the downstream side;
A detecting means provided between the feeding means and the conveying means for detecting the arrival of the sheet fed from the feeding means for each sheet ;
A double feed detecting means provided between the feeding means and the conveying means for detecting double feed of sheets fed from the feeding means;
Control means for controlling the feeding means,
The control means includes
And stopping or deceleration control of the feeding operation, and restarting or re-acceleration control after executing the stop or deceleration control, the repetitive control to the preceding detection result based rather the feeding means of said detecting means A sheet conveying apparatus characterized in that a sheet interval between a sheet and a succeeding sheet is created, and the restart or reacceleration control is executed on condition that there is no double feed detection by the double feed detection means . A feeding means for sequentially feeding sheets one by one into the sheet conveying path;
A conveying unit that is provided on the downstream side of the feeding unit and conveys the sheet fed by the feeding unit toward the downstream side;
A detecting means provided between the feeding means and the conveying means for detecting the arrival of the sheet fed from the feeding means for each sheet ;
A double feed detecting means provided between the feeding means and the conveying means for detecting double feed of sheets fed from the feeding means;
Control means for controlling the feeding means and the conveying means,
Wherein, while the speed control to be faster than the speed feed the sheet conveying speed of said feeding means by said conveying means, feeding at based rather said feeding means on a detection result of said detecting means and control of the stop or deceleration operation, the a stop or re-start or re-acceleration control after executing the deceleration control, and repeatedly controlling said control restarts or re-acceleration, the heavy feed detection by the double feed detecting means The sheet conveying apparatus is executed on the condition that there is no sheet.   The control unit performs re-acceleration control of the feeding operation by the feeding unit based on the detection result of the detecting unit, and performs control to perform transfer of sheet conveyance from the feeding unit to the conveying unit. The sheet conveying apparatus according to claim 1, wherein the sheet conveying apparatus is characterized. The control means temporarily stops the sheet feeding operation at the detection position of the detection means or a downstream position based on the detection result of the detection means, and resumes the feeding operation by the feeding means. sheet conveying device according to any one of claims 1 to 3, characterized. The feeding means can reversely feed the sheet,
The control means includes
Double feed sheet conveying device according to any one of claims 1 to 4, characterized in that to convey the sheet in the reverse direction to the feeding means when the. Wherein in a double feed detecting means and the detection means, the sheet conveying device according to any one of claims 1 to 5, characterized in that also serves the same ultrasonic sensor. An information reading apparatus comprising information reading means for reading information on a sheet conveyed by the sheet conveying apparatus according to claim 1 .

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