JP2014118273A - Sheet transport device and information reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a transport force for normally transporting an envelope and prevent unnecessary power consumption if invalidation of ultrasonic detection of multi-feed is selected.SOLUTION: If invalidation of ultrasonic detection of multi-feed is selected, a transport force for transporting a paper medium is set higher than that in a case of selecting validation of the ultrasonic detection of multi-feed. If the ultrasonic detection of multi-feed continues and it is determined that multi-feed occurs as a result of the ultrasonic detection of multi-feed despite the selection of the invalidation of ultrasonic detection of multi-feed, the transport force for transporting the paper medium is set higher than that in a case of selecting the validation of the ultrasonic detection of multi-feed.

Description

  The present invention detects a double feed in which a plurality of sheet-like members are carried while being stacked on each other in an apparatus having a function of mounting a plurality of sheet-like members and separating and conveying the sheet-like members one by one. The present invention relates to a sheet conveying device and an information reading device.

  Scanners, printers, copiers, printing machines, ATMs (Automated Teller Machines), and the like are equipped with a mechanism for separating and conveying sheet-like members one by one. However, there may be a possibility that a double feed is performed in which only one sheet-like member is conveyed while a part or the whole of two or more sheet-like members are overlapped. For this reason, the apparatus which conveys a sheet-like member needs the function to detect double feeding of a sheet-like member. As a mechanism for detecting the double feed of the sheet-like member, a double feed detection device is widely used in each field (see Patent Document 1).

  The multifeed detection device will be described with reference to FIG. FIG. 2 is a diagram showing an outline of a banknote double feed detection device described in Patent Document 1. As shown in FIG. The double feed detection device described in Patent Document 1 particularly relates to double feed detection using an ultrasonic sensor.

  The banknote 101 is a sheet-like member as a detection target. The ultrasonic transmission means 102 transmits ultrasonic waves to the banknote 101. The ultrasonic wave receiving unit 103 receives the ultrasonic wave transmitted from the ultrasonic wave transmitting unit 102. The ultrasonic wave receiving means 103 is installed so as to face the ultrasonic wave sending means 102 across the conveyance path of the banknote 101 so that the ultrasonic wave transmitted through the banknote 101 can be received.

The control unit 104 supplies a pulse signal to the ultrasonic driving unit 105 as an ultrasonic transmission signal. The ultrasonic drive means 105 amplifies the pulse signal supplied from the control means 104 and outputs it as an ultrasonic transmission pulse. Thereby, the ultrasonic wave transmission means 102 transmits an ultrasonic wave based on the ultrasonic wave transmission pulse by which the signal was amplified. Note that the pulse signal supplied by the control means 104 is, for example, a pulse signal for several cycles. This is generally called a burst wave.
The burst wave is transmitted at a frequency of once every several ms (milliseconds), for example.

  The signal amplification unit 106 amplifies the ultrasonic reception signal output from the ultrasonic reception unit 103. The signal amplification factor adjusting unit 110 adjusts the signal amplification factor of the signal amplification unit 106. Here, the signal amplification factor adjusting means 110 is, for example, a volume. Further, the adjustment of the signal amplification factor is performed, for example, for individual products before product shipment or by a product user.

  The A-D converter 107 converts the ultrasonic reception signal (analog signal) amplified by the signal amplification unit 106 into a digital signal and outputs the digital signal to the signal analysis unit 108. The signal analysis unit 108 analyzes the ultrasonic reception signal digitized by the A / D converter 107 and outputs the analysis result to the control unit 104.

  The storage unit 109 holds each setting value of the double feed detection device. As a result, the double feed detection device performs the double feed detection operation using the set value held in the storage unit 109.

  Next, the operation of the double feed detection device shown in FIG. 2 will be described. The ultrasonic wave transmitted from the ultrasonic wave transmitting means 102 hits the bill 101 and the ultrasonic wave receiving means 103 receives the transmitted wave. Thereby, the ultrasonic wave receiving means 103 outputs an ultrasonic wave reception signal that changes in accordance with the received signal intensity of the received ultrasonic wave. The signal amplifying unit 106 amplifies the ultrasonic reception signal output from the ultrasonic receiving unit 103 with an amplification factor according to the adjustment state of the signal amplification factor adjustment unit 110. The A-D converter 107 converts the ultrasonic reception signal amplified by the signal amplification unit 106 into a digital signal, and outputs the digitized ultrasonic reception signal to the signal analysis unit 108. The signal analysis means 108 analyzes the digitized ultrasonic reception signal output from the A / D converter 107. When the control unit 104 determines that double feeding is performed based on the analysis result of the signal analysis unit 108, the control unit 104 performs processing to notify the device or the user of the device that the double feeding has occurred.

  The double feed detection method shown in FIG. 2 is a method called a level determination method in which double analysis is detected by the signal analysis means 108 analyzing a change in the amplitude of the received ultrasonic reception signal. This level determination method will be further described. The ultrasonic receiving means 103 acquires the amplitude of the ultrasonic wave which conveyed the banknote 101 and permeate | transmitted the banknote 101, after setting the double feed determination threshold value beforehand. Compared with the amplitude of transmitted ultrasonic waves when the banknotes 101 are normally conveyed one by one, the amplitude of transmitted ultrasonic waves when the banknotes 101 are double-fed is a small value. This is because the amount of attenuation of ultrasonic waves increases according to the number of stacked banknotes. Therefore, by comparing the amplitude of the ultrasonic reception signal acquired by the ultrasonic receiving unit 103 and amplified by the signal amplifying unit 106 with the double feed determination threshold value in the signal analyzing unit 108, the double feed of the bill 101 is performed based on the comparison result. It becomes possible to detect.

Japanese Patent No. 3860126

  An example of conveying a check (collectively a check or bill) as a sheet-like member will be described. Normally, the check is transported as it is, but the damaged check is stored in the transport auxiliary member and transported. For example, a translucent envelope called an envelope is used as the conveyance assisting member. The number of envelopes in which checks are stored is the same as the number of checks, for example. This is because the envelope is formed by a transparent sheet on the front surface and a sheet on the back surface, and a check is inserted between the envelopes. Since the envelope storing the check is the same number of sheets as when three sheets are double-fed, the same double-feed detection level is attenuated. For this reason, the double feed detection level when the envelope is transported is smaller than the double feed detection level when only the check is transported. Therefore, also when the envelope storing the check is conveyed, the control means 104 determines that double feeding has occurred. Similarly, when a non-transparent envelope is conveyed and a reading operation is performed, the control unit 104 determines that double feeding has occurred.

  For the above reasons, when transporting an envelope containing a check, or when transporting an envelope that is not transparent, the user can detect a double feed when he / she wants to avoid stopping the reading operation due to the determination of double feed. The function needs to be disabled.

  On the other hand, as compared with the case where the check is conveyed, a larger conveying force is required when the envelope is conveyed. For example, in the case of transporting an envelope storing a check, substantially the same transport force is required to transport three checks simultaneously.

  Furthermore, when the check and the envelope are mixed, the transport force necessary for transporting the check and the transport force necessary for transporting the envelope are different, but the transport force is the same. In a period in which there is no envelope in the conveyance path and only a check exists, power is wasted.

  Note that the above-described problem is not limited to the check and envelope, but may be present in the same manner depending on the type of sheet thickness, material, and the like when other sheets are conveyed.

    In order to solve the above-described problems, a sheet conveying apparatus according to the present invention includes a conveying unit that conveys a sheet, a multi-feed detecting unit that detects multi-feeding of sheets, and valid / invalid of multi-feed detection by the multi-feed detecting unit. And a control unit that controls the conveyance force of the sheet material by the conveyance unit to a greater extent than when the multi-feed detection is disabled by the selection unit. And means.

  According to the present invention, sheet conveyance according to various types of sheets can be realized. Further, even when the envelope is conveyed as a sheet, there is no case where the conveying force is insufficient and the motor steps out and the conveying operation is stopped, or the conveying force is insufficient and the conveying speed is not lowered. Further, even if the user disables the double feed detection and forgets to enable it again, the conveyance force does not remain large, so that power is not wasted. Further, even when the sheet and the envelope are mixedly loaded, the conveyance force is not kept large during the period in which only the check exists in the conveyance path, so that power is not consumed unnecessarily.

The figure which shows schematic structure of the ultrasonic double-feed detection apparatus in the 1st Embodiment of this invention. The figure which showed the outline of the conventional ultrasonic multifeed detection apparatus. Schematic of a conveying apparatus. The flowchart in the 1st Embodiment of this invention. Explanatory drawing (check) of a conveying apparatus. Explanatory drawing (envelope) of a conveying apparatus. The flowchart in the 2nd Embodiment of this invention. The flowchart in the 3rd Embodiment of this invention. Explanatory drawing (check) of a conveying apparatus. Explanatory drawing (envelope) of a conveying apparatus. Explanatory drawing of conveyance device (mixed loading of check and envelope). Explanatory drawing of conveyance device (mixed loading of check and envelope).

[Embodiment 1]
FIG. 1 is a diagram illustrating a schematic configuration of a sheet conveying apparatus for conveying a sheet material according to the first embodiment. The sheet conveying device is used, for example, in the preceding stage of an information reading device that conveys a sheet material such as a check to a predetermined reading position and reads information recorded on the sheet material magnetically or optically. Note that this sheet conveying apparatus has a double feeding detection unit that detects double feeding of sheet materials, and can be called a double feeding detection apparatus by paying attention to this point. Such a double feed detection device is a device that detects “double feed”, which is a phenomenon in which two or more sheet-like members are conveyed by being overlapped using an ultrasonic sensor or an optical sensor.

  Here, in the present embodiment, a multifeed detection device using an ultrasonic sensor as a multifeed detection unit will be described, but the present invention is not limited to this. Check 1 is an example of a sheet-like member that is a conveyance target. In addition, in this embodiment, although the check is employ | adopted as an example of a sheet-like member, a banknote etc. may be sufficient as the sheet-like member of this invention.

  This apparatus includes a double feed detection selection unit 11 for selecting whether to enable or disable double feed detection. When the ultrasonic double feed detection is enabled, the operator operates the double feed detection selection unit 11 to select the effective ultrasonic double feed detection. The double feed detection selection unit 11 is, for example, a mechanical switch or a switch that can be selected on application software. Conversely, when invalidating the ultrasonic double feed detection, the operator operates the double feed detection selection unit 11 to select invalidity of the ultrasonic double feed detection.

  In this embodiment, when invalidation of double feed detection is selected, that is, when double feed detection is invalidated, in this embodiment, even if the operation of the ultrasonic double feed detection unit 1002 is stopped, it is stopped. It does not have to be. If double feed detection is not stopped, the detection result is not used, and even if double feed is detected, no error is generated.

  The control unit 8 supplies a pulse signal (hereinafter referred to as an ultrasonic transmission signal) to the ultrasonic driving unit 9 as a signal for transmitting an ultrasonic wave. The ultrasonic drive unit 9 amplifies the ultrasonic transmission signal supplied from the control unit 8 and outputs an ultrasonic transmission pulse. Thereby, the ultrasonic transmission part 2 transmits an ultrasonic wave based on the ultrasonic transmission pulse by which the signal was amplified. In addition, the ultrasonic transmission signal which the control part 8 supplies to the ultrasonic drive part 9 is a signal which has a pulse for several cycles over a fixed time, for example.

  The ultrasonic transmission unit 2 transmits ultrasonic waves to the check 1. The ultrasonic receiver 3 receives the ultrasonic wave transmitted by the ultrasonic transmitter 2. As shown in FIG. 1, the ultrasonic receiver 3 is installed so as to face the ultrasonic transmitter 2 across the conveyance path of the check 1 so that the ultrasonic wave that has passed through the check 1 can be received. . Thereby, the ultrasonic wave transmitted from the ultrasonic wave transmitting unit 2 passes through the check 1 and the ultrasonic wave receiving unit 3 receives the transmitted wave. The ultrasonic receiver 3 outputs an ultrasonic reception signal whose signal intensity changes according to the reception intensity of the received ultrasonic wave. The ultrasonic transmission unit 2 and the ultrasonic reception unit 3 arranged in this way constitute an ultrasonic double feed detection unit 1002.

  As described above, when the check 1 exists in the transport path, the ultrasonic wave that has passed through the check 1 is received by the ultrasonic wave reception unit 3. On the other hand, when the check 1 is not present on the conveyance path, the ultrasonic wave transmitted by the ultrasonic wave transmission unit 2 is received by the ultrasonic wave reception unit 3 as it is.

  The signal amplification unit 4 amplifies the ultrasonic reception signal output from the ultrasonic reception unit 3. If there is a check 1 that is a conveyance target between the ultrasonic transmitter 2 and the ultrasonic receiver 3, the ultrasonic wave transmitted from the ultrasonic transmitter 2 is attenuated until it reaches the ultrasonic receiver 3, It will be a weak signal. Further, the amplitude of the ultrasonic reception signal output from the ultrasonic reception unit 3 is also weak. Therefore, this is amplified by the signal amplifying unit 4 and raised to a signal amplitude capable of determining double feed detection.

  The signal amplification factor adjustment unit 5 adjusts the signal amplification factor of the signal amplification unit 4. Here, the signal amplification factor adjustment unit 5 is, for example, a volume (variable resistor). Further, the adjustment of the signal amplification factor is performed, for example, for individual products before product shipment or by a product user.

  The AD converter 6 converts the ultrasonic reception signal (analog signal) amplified by the signal amplification unit 4 into a digital signal and outputs the digital signal to the signal analysis unit 7.

  The signal analysis unit 7 analyzes the ultrasonic reception signal digitized by the A / D converter 6 and outputs the analysis result to the control unit 8. The control unit 8 controls the operation of the conveyance motor drive unit 13, the conveyance motor 14, and the conveyance roller 15 according to the analysis result, or displays a message on the display unit 12 to notify the user of double feeding. I do. As will be described later, the transport motor drive unit 13 is controlled to adjust the torque of the transport motor 14. The signal analysis unit 7 and the control unit 8 can be realized by, for example, a combination of a CPU and a computer program, or an ASIC.

  The storage unit 10 holds setting values, data, and the like that are used in double feed detection. Specifically, the storage unit 10 includes the number of pulses of the ultrasonic transmission signal, the amplitude of the ultrasonic transmission signal, the frequency of the ultrasonic transmission signal, the acquisition time of the ultrasonic reception signal, the ultrasonic double feed detection level (threshold), Hold the setting value. In addition, the control unit 8 controls each unit to perform double feed detection using those set values held in the storage unit 10.

  FIG. 3 is a schematic configuration diagram of the sheet conveying apparatus 1000. FIG. 3 shows the case of the sheet conveying apparatus installed so that the short direction of the check 1 is vertical. The sheet conveying apparatus 1000 includes, for example, a sheet feeding unit 1001 for inserting a check and an envelope, an ultrasonic multi-feed detecting unit 1002 for detecting double feeding immediately after sheet feeding, and a conveying path for conveying the check and envelope. A unit 1003 and a paper discharge unit 1004 for discharging check and envelopes. For example, an image reading unit, a magnetic ink character reading unit, or a printing unit, such as an image reading unit, a printing unit, or the like may be disposed in the conveyance path unit 1003 for reading or recording information recorded on the sheet. it can.

  FIG. 4 is a flowchart illustrating an example of a double feed detection setting and a conveyance force setting method according to the first embodiment. FIG. 5 is a schematic diagram in which the sheet conveying device is developed for easy explanation. The flow in FIG. 4 is executed by the control unit 8.

  In step S101 in FIG. 4, the control unit 8 in FIG. 1 determines the state set by the double feed detection selection unit 11. When the ultrasonic double feed detection is set to be valid (“valid setting” in S101), it is determined that the sheet material to be conveyed is a check, and the conveyance force is set to be steady (S103). For example, when the conveyance roller is driven by a stepping motor, the conveyance force is set by a known technique such as changing the setting of the current value flowing in each phase. Increasing the current value increases the torque of the transport motor. In S103, the torque control unit 8 of the conveyance motor sets a steady state as the conveyance force in the conveyance motor drive unit 13 of FIG. The transport motor 14 is driven according to the set transport force, and the transport force is transmitted to the transport roller 15.

  In FIG. 5, Check 1 is inserted in the paper feeding unit 1001, and when the paper is fed without being double fed, the ultrasonic double feeding detection unit 1002 determines that the double feeding is not performed. If the paper is fed in double feed, processing such as indicating that the check is double fed and stopping the conveyance and displaying the double feed is performed. When the double feed is not detected by the ultrasonic double feed detection unit 1002, the check 1 is discharged to the paper discharge unit 1004 via the transport path unit 1003.

  On the other hand, when the ultrasonic double feed detection is set to be invalid in S101 of FIG. 4 (“invalid setting” in S101), it is determined that the envelope is conveyed, and the conveyance force is set to be large (S102). The control unit 8 sets a large conveyance force to the conveyance motor drive unit 13 in FIG. The transport motor 14 is driven according to the set transport force, and the transport force is transmitted to the transport roller 15. The amount of current to be applied to the drive motor for increasing the conveying force to normal or large is determined in advance, for example experimentally, according to the weight of the check or the weight of the check placed in the envelope. Control can be performed according to the determination result of whether the feed detection is valid or invalid.

  FIG. 6 is a schematic diagram in which the sheet conveying apparatus is developed, and is a view when an envelope is inserted into the sheet feeding unit. An envelope 50 is inserted into the paper feeding unit 1001. The envelope 50 is discharged to the paper discharge unit 1004 via the conveyance path unit 1003.

  As described above, when the invalidity of the double feed detection is selected, the conveyance force of the paper medium is increased as compared with the case where the validity of the ultrasonic double feed detection is selected. For this reason, even when the envelope is transported, there is no case where the transport force is insufficient and the motor steps out, the transport operation is not stopped, or the transport force is insufficient and the transport speed is not lowered.

[Embodiment 2]
In the second embodiment, the double feed detection operation for the selection of valid / invalid of double feed detection is slightly different from that in the first embodiment. In the first embodiment, when double feed detection invalidation is selected by the double feed detection selection unit 11, the double feed detection itself may be stopped. However, in this embodiment (the same applies to the third embodiment), double feed detection is performed. Even if invalidity is selected (or set), the double feed detection operation is not invalidated and executed. That is, even if “invalid” is selected for the double feed detection, the double feed detection unit operates and the detection result is used for transport control. If the double feed detection is enabled, error handling such as stopping the conveyance and notifying the user of the double feed is performed when the double feed is detected. On the other hand, if invalidity of double feed detection is selected, the above-described processing is not performed even when double feed is detected. Hereinafter, the sheet conveying apparatus of the present embodiment will be described, and the configuration thereof is as shown in FIGS. 1 and 3 as in the first embodiment.

  FIG. 7 is a flowchart illustrating an example of the double feed detection setting and the conveyance force setting method according to the second embodiment. This flow is executed by the control unit 8. The sheet conveying apparatus will be described with reference to FIGS. 5 and 6 as in the first embodiment.

  In step S201 in FIG. 7, the control unit 8 determines whether the state selected by the double feed detection selection unit 11 is selected, that is, whether valid or invalid multifeed detection is selected.

  When the ultrasonic double feed detection is set to be valid (valid setting in S201), it is determined that the check is to be conveyed, and the conveyance force is set to be steady (S205). The control unit 8 sets a steady state as the conveyance force in the conveyance motor drive unit 13 of FIG. The transport motor 14 is driven according to the set transport force, and the transport force is transmitted to the transport roller 15.

  In FIG. 5, Check 1 is inserted in the paper feeding unit 1001, and when the paper is fed without being double fed, the ultrasonic double feeding detection unit 1002 determines that the double feeding is not performed. If the paper is fed in double feed, processing such as indicating that the check is double fed and stopping the conveyance and displaying the double feed is performed. When the double feed is not detected by the ultrasonic double feed detection unit 1002, the check 1 is discharged to the paper discharge unit 1004 via the transport path unit 1003.

  On the other hand, if it is determined in FIG. 7 that the ultrasonic double feed detection is set to invalid (invalid setting in S201), the process branches to S202. In the ultrasonic double feed detection unit 1002 of the present embodiment, even if the operator sets the ultrasonic double feed detection to invalid, the ultrasonic double feed detection is executed.

  In S202, the ultrasonic double feed detection unit 1002 determines the detection result. If the ultrasonic double feed detection unit 1002 detects double feed (YES in S202), it is determined that the envelope is to be conveyed as shown in FIG. 6, and the conveyance force is set to be large (S203). The control unit 8 sets a large conveyance force to the conveyance motor drive unit 13 in FIG. The transport motor 14 is driven according to the set transport force, and the transport force is transmitted to the transport roller 15. The envelope 50 is discharged to the paper discharge unit 1004 via the conveyance path unit 1003.

  On the other hand, if the ultrasonic double feed detection unit 1002 has not detected double feed (NO in S202), it is determined that the check is to be carried as shown in FIG. 5, and the carrying force is set to be steady (S204). The control unit 8 sets a steady state as the conveyance force in the conveyance motor drive unit 13 of FIG. The transport motor 14 is driven according to the set transport force, and the transport force is transmitted to the transport roller 15. The check 1 is discharged to the paper discharge unit 1004 via the transport path unit 1003.

  As described above, even if the user is set to disable double feed detection, if the double feed is not detected, the torque of the carry motor is not increased, and the sheet material is loaded with a steady carry force. Transport. For this reason, even if the user disables double feed detection for envelope processing and then forgets to re-enable it after finishing the processing, the conveyance force will not remain large, which is useless. There is no power consumption.

  In the present embodiment, an example has been described in which the conveyance force is made steady when the operator sets the ultrasonic double feed detection to be invalid, and the conveyance force is increased when the double feed is detected. The conveyance force may be increased when the feed detection is set to be invalid, and the conveyance may be made steady when the double feed is not detected.

[Embodiment 3]
The sheet conveying apparatus of the present embodiment has the configuration shown in FIGS. 1 and 3, but as described with reference to FIGS. 9, 10, 11, and 12, the conveying path is composed of two or more paper media. It is the length to enter. 9, FIG. 10, FIG. 11, and FIG. 12 are schematic views in which the conveying device is developed. FIG. 9 is a diagram when a check is inserted into the paper feeding unit. A check 1 is inserted in the paper feeding unit 1001. FIG. 10 is a view when an envelope is inserted into the paper feeding unit. An envelope 50 is inserted into the paper feeding unit 1001.

  FIG. 8 is a flowchart illustrating an example of a multifeed detection setting and a conveyance force setting method according to the third embodiment. This flow is executed by the control unit 8.

  In step S301 in FIG. 8, the control unit 8 in FIG. 1 determines the state set by the double feed detection selection unit 11.

  If the ultrasonic double feed detection is set to be valid, it is determined that the check is to be conveyed (valid setting in S301), and the conveyance force is set to be steady (S307). The control unit 8 sets a steady state as the conveyance force in the conveyance motor drive unit 13 of FIG. The transport motor 14 is driven according to the set transport force, and the transport force is transmitted to the transport roller 15.

  In FIG. 9, check 1 is inserted in the paper feed unit 1001, and if the paper is fed without being fed, the ultrasonic double feed detection unit 1002 determines that the double feed is not performed. If the paper is fed in double feed, processing such as indicating that the check is double fed and stopping the conveyance and displaying the double feed is performed. When the double feed is not detected by the ultrasonic double feed detection unit 1002, the check 1 is discharged to the paper discharge unit 1004 via the transport path unit 1003.

  Next, a case where ultrasonic double feed detection is disabled will be described. The description overlapping with the case where it is enabled will be omitted.

  In S301 of FIG. 8, when the ultrasonic double feed detection is set to invalid (invalid setting of S301), the process branches to S302. In the ultrasonic double feed detection unit 1002 of FIGS. 9, 10, 11, and 12, ultrasonic double feed detection is executed even if the operator sets the ultrasonic double feed detection to invalid.

  When the ultrasonic double feed detection unit 1002 does not detect double feed (NO in S302), it is determined that the check is to be conveyed. In this case, as shown in FIG. 11, an envelope 50 may already exist in the conveyance path.

  Therefore, if double feed is not detected, the process branches to S303 to determine the presence or absence of an envelope in the transport path 1003. When the envelope is being transported in the transport path (YES in S303), the transport force is set to be large (S304). Whether or not the envelope is being transported in the transport path can be determined based on the determination result by the ultrasonic double feed determination unit 1002, the length of the transport path, the paper feed timing, and the transport speed. For example, within a predetermined time (determined by the conveyance speed and the length of the conveyance path) where the detected sheet is in the conveyance path 1002 after the double feeding is detected by the ultrasonic multi-feed determination unit 1002, the envelope is in the conveyance path 1003. Can be determined. The control unit 8 sets a large conveyance force to the conveyance motor drive unit 13 in FIG. The transport motor 14 is driven according to the set transport force, and the transport force is transmitted to the transport roller 15. The check 1 and the envelope 50 are discharged to the paper discharge unit 1004 via the conveyance path unit 1003.

  On the other hand, as shown in FIG. 12, when it is determined that only the check 1 is present on the conveyance path 1003 (NO in S303), the conveyance force is set to be steady (S305). The control unit 8 sets a steady state as the conveyance force in the conveyance motor drive unit 13 of FIG. The transport motor 14 is driven according to the set transport force, and the transport force is transmitted to the transport roller 15. The check 1 is discharged to the paper discharge unit 1004 via the transport path unit 1003.

  If the ultrasonic double feed detection unit 1002 detects double feed (YES in S302), it is determined that the envelope is transported as shown in FIG. 9, and the transport force is larger than the steady state and can withstand the envelope transport. Set (S306). The control unit 8 sets a steady state as the conveyance force in the conveyance motor drive unit 13 of FIG. The transport motor 14 is driven according to the set transport force, and the transport force is transmitted to the transport roller 15. The check 1 is discharged to the paper discharge unit 1004 via the transport path unit 1003.

  S302 to S303 can be rewritten as follows. That is, if double feeding is detected in S302, the timer is started and the process branches to S306. The value of the timer is the predetermined time used for the determination in S303 described above. In S303, it is determined whether or not the timer has expired. If it has expired, it is determined that the check is being carried, and the process branches to S305. If it has not expired, it is determined that the envelope is being carried. The process branches to S304.

  As described above, even if the user disables the ultrasonic double feed detection and forgets to enable it again, the conveyance force does not remain large, and power is not wasted. Also, during the period in which the paper medium determined to be double-feed exists in the transfer path, the paper medium transfer force is increased compared to the case where the ultrasonic multi-feed detection is enabled, and the paper determined not to be double-feed The period during which only the medium is present in the conveyance path is set to the same conveyance force as when ultrasonic multifeed detection is enabled, so there is no envelope in the conveyance path when the check and envelope are mixed. In the period in which only the check exists, the conveyance force does not remain large, so that power is not wasted.

  In the present embodiment, an example has been described in which the conveyance force is made steady when the operator sets the ultrasonic double feed detection to be invalid, and the conveyance force is increased when the double feed is detected. The conveyance force may be increased when the feed detection is set to be invalid, and the conveyance force may be made steady when the double feed is not detected.

  In the above-described embodiment, the check and the conveyance of the envelope are mainly exemplified. However, the present invention can be applied to other sheets (for example, thin paper, thick paper, paper of different materials, etc.). . In any case, the present invention can realize good sheet conveyance according to a wide variety of sheets.

1: Check 2: Ultrasonic transmission unit 3: Ultrasonic reception unit 4: Signal amplification unit 5: Signal amplification factor adjustment unit 6: AD converter 7: Signal analysis unit 8: Control unit 9: Ultrasonic drive unit 10: Storage Unit 11: double feed detection selection unit 12: display unit 13: transport motor drive unit 14: transport motor 15: transport roller 50: envelope 1000: transport device 1001: paper feed unit 1002: ultrasonic multi-feed detection unit 1003: transport path Unit 1004: paper discharge unit

Claims (6)

Conveying means for conveying the sheet;
A double feed detecting means for detecting double feed of the sheet;
Selecting means for selecting valid or invalid of double feed detection by the double feed detection means;
When invalidity of double feed detection is selected by the selection means, control means for largely controlling the conveying force of the sheet material by the conveyance means, compared to the case where the validity of double feed detection is selected;
A sheet conveying apparatus comprising: Even when invalidity of double feed detection is selected by the selection means, double feed detection by the double feed detection means is performed,
The control means, even when invalidity of double feed detection is selected by the selection means, if double feed is not detected by the double feed detection means, the transport force of the sheet material by the transport means is The sheet conveying apparatus according to claim 1, wherein the sheet conveying device is controlled to have a conveying force equivalent to that when the selection unit selects the validity of the double feed detection.   The control means is configured such that even when the multi-feed detection is disabled by the selection means and multi-feed is detected by the multi-feed detection means, the sheet determined to be multi-feed by the multi-feed detection means. 3. The sheet conveying force by the conveying unit is controlled to a conveying force equivalent to that when the multi-feeding effective is selected by the selecting unit during a period in which no sheet exists in the conveying path. The sheet conveying apparatus according to 1.   4. The sheet conveying apparatus according to claim 1, wherein the double feed detection unit is a double feed detection unit using an ultrasonic sensor or an optical sensor. 5.   When the multi-feed detection is enabled by the selection unit and the multi-feed is detected by the multi-feed detection unit, the multi-feed detection unit further includes a notification unit that notifies the user that the multi-feed has been detected. The sheet conveying apparatus according to any one of claims 1 to 4. A sheet conveying device according to any one of claims 1 to 5,
Reading means for reading information recorded on a sheet conveyed to a predetermined reading position by the sheet conveying device;
An information reading apparatus comprising:

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