JP2001240272A - Medium conveying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bond issuing machine and an automatic cash dispensing machine of high operatability, capable of being continuously used without stopping the machine even in failure of components. SOLUTION: In a medium conveying path having plural sensors for checking the conveying of a medium, a failed sensor is separated when the failure of the sensor is detected, and a timing for feeding out a next medium to the conveying path is controlled to convey only a sheet of medium between two sensors in a good condition on the medium conveying path. Whereby the machine can be continuously used without stopping the same, the machine of high operatability can be realized, and the medium can be stably and surely conveyed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a certificate issuing device and an automatic teller machine (ATM) used in a financial institution.

[0002]

2. Description of the Related Art Banks, securities companies, etc.
In recent years, financial terminal devices such as TM and certificate issuing devices have been
The number of installations is increasing due to the need to reduce labor costs and improve customer service. On the other hand, in order to efficiently perform customer service during business hours, it is necessary to improve the utilization rate of these financial terminal devices and increase the reliability of the entire system. For this reason, conventionally, regarding the media transport of financial terminal devices, the passage of the media was monitored by a plurality of sensors provided in the media transport path to check that the transport of valuable media was performed normally, and a particularly strict check was made. Need to do. When an abnormality or failure occurs in the detection sensor, which is one of the causes of the medium conveyance abnormality, it is necessary to stop the apparatus and replace the sensor. In order to minimize downtime for the replacement work,
Methods have been taken to increase the stock of parts and to have maintenance personnel always on standby to speed up the recovery from failures. However, in any case, the cost is increased and parts replacement time is required, during which time the apparatus must be stopped. Therefore, there is a demand for a low-cost method that can be used continuously without stopping the apparatus even if a component failure occurs. As a method for continuously using the apparatus without stopping even if a component failure occurs in response to such a request, as disclosed in Japanese Patent Application Laid-Open No. H10-139214, "reducing monitoring of a failed sensor, Dummy output means for processing the output information of the failed sensor based on the output information of the normal sensor is provided so that the jam of the object can be monitored even if the sensor has failed. " 5486
As disclosed in No. 0, "except for a sensor determined to be a sensor failure, jam detection can be performed instead of a number check and a section jam check by other banknote passage passage sensors" to continue use of the apparatus. Technology that takes various measures for high operation such as performing is disclosed.

[0003]

However, a dummy output means for reducing the monitoring of a failed sensor and processing the output information of a failed sensor based on the output information of a normal sensor is provided. In this method, the dummy signal does not represent the actual movement of the medium, so the transport operation is likely to be disordered,
There is a disadvantage that the abnormality detection operation is likely to be unstable.

[0004] In addition, in the method in which "jam monitoring can be performed by using a sensor other than a sensor determined to be a sensor failure and using the other paper money passage passage sensors instead of the number check and the section jam check", the failure sensor is omitted. As a result, the physical distance between the good sensors becomes longer, and a plurality of bills are simultaneously present and conveyed between the longer conveyance paths. If a bill jams for any reason, more bills will be damaged at one time, and there is a disadvantage that recovery work requires a lot of time, and stable and reliable media transport is performed. I couldn't do that.

The technical problem of the present invention is to solve such a conventional problem and to stably convey a medium even if a sensor on a conveyance path fails, so that the apparatus can be used continuously. It is another object of the present invention to provide a control device for preventing a decrease in customer service due to a device down.

[0006]

In order to achieve the above-mentioned object, according to the control device of the present invention, when an abnormality or failure of a sensor on the medium transport path is detected, the output of the sensor is separated, and the sensor is connected to the failed sensor. When the sensor on the front side adjacent to the medium traveling direction detects the front end of the medium, and the sensor on the rear side in the medium traveling direction adjacent to the failed sensor detects the rear end of the medium, the next media feeding mechanism unit 26 is notified. By controlling so as to issue a feeding start timing for instructing feeding of the medium onto the feeding path, stable and reliable feeding of the medium can be realized.

FIG. 1 shows a configuration diagram of the present invention. The dotted line represents a control unit, which is a main control unit 1 for performing overall control of the apparatus, a sensor signal detection unit 2 for detecting a signal read by the sensor, and a failure when a sensor failure is detected and a sensor failure is detected. Sensor failure detection unit 3 for separating the output of the sensor
A jam time monitoring timer 5 that switches the sensor jam monitoring time according to a command from the main control unit 1, and instructs the medium feeding mechanism unit 26 to feed the next medium onto the transport path according to a command from the main control unit 1. It comprises a medium feeding timing control unit 6 and the like.

The upper part of the figure is a mechanism, which is a medium storage mechanism 20 for storing media, a medium feeding mechanism 26 for feeding out the medium stored in the medium storage 20 one by one to a transport path, and a transport mechanism. It comprises a path 22, a transport roller 23 for sandwiching and transporting the medium on the transport path, a plurality of sensors 31 to 34 provided on the transport path for detecting the medium, a medium discharge unit 21 for storing the medium, and the like.

When a sensor failure is detected by this configuration, the sensor failure detecting section 3 disconnects the output of the failed sensor, and in accordance with a command from the main control section 1, sends the following to the medium feeding mechanism section 26. By controlling the timing at which the medium is fed out onto the transport path, only one medium can be present between two normal sensors on the transport path. By switching the medium detection predetermined time value of the sensor adjacent to the front side in the medium traveling direction to have a value obtained by adding the predetermined time value of the failed sensor, the same detection accuracy as in normal use without sensor failure Jam detection is possible.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 2 is a block diagram of a certificate issuing apparatus according to an embodiment of the present invention. The medium storage 20 stores unprinted certificates such as securities and bank notes. An operator or a maintenance person stores a predetermined number of certificates in the medium storage 20. This certificate contains the payout amount, payee name,
Necessary items such as the payout date and time and the name of the payer are printed on the certificate and handed over to the customer. Now, as an example, a medium transport operation when a print command is received from a host device will be described.

First, when a print command is received from a higher-level device, the medium feeding timing control unit 6 is controlled via the main control unit 1.
Issues an instruction to the medium feeding mechanism 26, the medium storage 2
0 are fed out one by one onto the transport path 22, and the medium is transported by the transport rollers 23. The printing unit 24 provided in the middle of the transport path prints predetermined items designated by the host device. The medium is transported again by the transport rollers 23 installed in the transport path 22 and stored in the medium discharge unit 21. . In general, the position of the sensor for detecting the transport state of the medium is set to be equal to or less than the maximum length of the medium in order to guarantee the accuracy of detecting the medium and reduce costs and increase efficiency. In the present embodiment, since the maximum length of the medium is about 15 cm, a description will be given of a certificate issuing apparatus having the following four sensors arranged at intervals of about 20 cm.

A sensor 31 provided at the outlet of the medium storage 20 for monitoring the start of printing on the medium; a sensor 32 provided at the entrance of the printing unit 24 for monitoring that the medium has been carried into the printing unit 24; Four sensors are provided: a sensor 33 provided at an outlet of the medium 24 and monitoring that the medium is unloaded from the printing unit 24, and a sensor 34 provided at the inlet of the medium discharge unit 21 and monitoring the completion of medium discharge. .

An operation panel 25 having various keys operated by the operator and a display unit for notifying the operator of the state of the apparatus.
There is.

FIG. 3 relates to the feeding control of the present invention and illustrates the medium feeding control (intermittent feeding control) when the sensor 32 is out of order. Hereinafter, the transport state of the medium at each time timing will be described. (1): The first medium is fed from the medium storage 20 to the transport path. (time t1) (2): The first medium passes through the sensor 31. (time t2) (3): When the leading end of the first medium reaches the sensor 33, the second medium is fed out of the medium storage. (time t3) (4): The second medium passes through the sensor 31, and the first medium reaches the sensor. (t4 time) (5): When the leading end of the second medium reaches the sensor 33, the third medium is fed out of the medium storage. (time t5) (6): The third medium passes through the sensor 31, the second medium reaches the sensor 34, and the first medium is discharged to the medium discharge unit. (time t6) (7): The third medium reaches the sensor 33, and the second medium is discharged to the medium discharge unit. (t7 time) (8): The third medium reaches the sensor 34. (t8 time) (9): The third medium passes through the sensor 34 and is discharged to the medium discharge section. (t9 time) As described above, when a good sensor (in this case, the sensor 33) adjacent to the front of the failed sensor 32 with respect to the medium advancing direction detects the leading end of the medium, it moves onto the transport path of the next medium. , It is possible to convey only one medium between the sensor 31 and the sensor 33.

FIG. 4 shows the medium feeding control (intermittent feeding control) when the sensor 33 is out of order. Similarly to the above, the transport state of the medium at each time timing will be described below. (1): The first medium is fed from the medium storage 20 to the transport path. (time t1) (2): The first medium passes through the sensor 31. (time t2) (3): When the rear end of the first medium has passed the sensor 32, the second medium is fed out of the medium storage. (time t3) (4): The second medium passes through the sensor 31, and the first medium reaches the sensor. (t4 time) (5): When the rear end of the second medium has passed through the sensor 32, the third medium is fed out of the medium storage. (time t5) (6): The third medium passes through the sensor 31, the second medium reaches the sensor 34, and the first medium is discharged to the medium discharge unit. (t6 time) (7): The second medium is discharged to the medium discharge section. (t7 time) (8): The third medium reaches the sensor 34. (t8 time) (9): The third medium passes through the sensor 34 and is discharged to the medium discharge section. (t9 time) As described above, when a good sensor (in this case, the sensor 32) adjacent to the rear of the failed sensor 33 in the medium advancing direction detects the rear end of the medium, it moves onto the transport path of the next medium. , It is possible to transport only one medium between the sensor 32 and the sensor 34.

FIG. 5 relates to the feed control of the present invention.
This diagram illustrates the medium feeding control (single-sheet feeding control) when both the sensor 32 and the sensor 33 are out of order. Similarly to the above, the transport state of the medium at each time timing will be described below. (1): The first medium is fed from the medium storage 20 to the transport path. (time t1) (2): The first medium passes through the sensor 31. (time t2) (3): When the rear end of the first medium has passed the sensor 34, the second medium is fed out of the medium storage. (t3 time) (4): The second medium passes through the sensor 31. (t4 time) (5): When the rear end of the second medium has passed the sensor 34, the third medium is fed out of the medium storage. (time t5) (6): The third medium passes through the sensor 31. (time t6) (7): The third medium is discharged to the medium discharge section after passing through the sensor 34. (t7 time) As described above, the failed sensor 3
When a good sensor (in this case, the sensor 34) adjacent to the front side of the sensor 2 and the sensor 33 detects the trailing end of the medium, it instructs the next medium to be fed out. Media can be transported.

Next, FIG. 6 shows a jam time monitoring timer table of the present invention.

In a normal state (first timer value) when the sensor is not out of order, T1 is set for each of the sensors 31 to 34, respectively.
~ T4. During normal operation in which all sensors are normal, the times T1 to T4 are used as they are as the jam monitoring time Ti (i = 1, 2, 3, 4). Therefore, now, taking the case where the sensor 32 has failed as an example,
This will be described below.

When either the sensor 32 or the sensor 33 has failed or both sensors have failed, Tai (i = 1, 2, 3,.
4) is used. Sensor failure (in this case sensor 3
When 2) occurs, T2 + T3 obtained by adding the timer value of the failed sensor 32 (in this case, T2) to the timer value of the good sensor (in this case, the sensor 33) adjacent to the medium in the medium advancing direction is calculated as the new Ta3. Timer value (second timer value)
Set as

When both the sensor 32 and the sensor 33 fail, the timer value of the failed sensor 32 becomes the timer value of the good sensor (in this case, the sensor 34) adjacent to the medium in the medium traveling direction. Value (in this case T
T2 + T3 + T4, which is the sum of 2) and the timer value of the sensor 33 (T3 in this case), is set as a new timer value of Ta4 (second timer value).

FIG. 7 is a flowchart (1) for determining a sensor failure.

First, when the power of the certificate issuing device is turned on, the sensor failure determination unit 4 is started to determine whether or not the sensor has failed. That is, it is determined whether any of the sensors 31 to 34 is on (SA1). When any one of the sensors 31 to 34 is on, a "medium present" display is performed on the operation panel (SA2). The operator presses the "reset key" on this display (SA3). When the "reset key" is pressed, the transport motor is turned on for a predetermined time in the forward direction to confirm whether or not a medium exists on the transport path (SA4). At this time, it is determined whether there is a change in the sensor output of any of the sensors 31 to 34 (SA
5). If there is no change in the sensor output, the transport motor is turned on in the reverse direction for a predetermined time (SA6). Again, sensor 3
It is determined whether there is a change in any one of the sensor outputs 1 to 34 (SA7). If there is no change in any of SA5 and SA7, it is determined that one of the sensors 31 to 34 is in an ON state due to a failure (SA8). At this time, the display of “sensor abnormality” is performed on the operation panel 25 (SA11), and the replacement work is prompted (SA11).
12). When all the sensors 31 to 34 are off, it is considered that there is no sensor abnormality, and the operation panel 2
5, the "continuous feeding mode" is displayed, the internal flags are set to make the state executable, and the online state is set to wait for a certificate issuance instruction from the host device (SA9).

FIG. 8 is a flowchart (2) for determining a sensor failure.

Here, a method of judging a failure of the sensors 32 and 33 and the setting of internal flags when a failure is judged will be described.

First, when both the sensors 32 and 33 are on, it is determined that both the sensors 32 and 33 are out of order (S
B1) At this time, each sensor failure flag (in this case, the sensor 32 failure flag and the sensor 33 failure flag) is turned on because it is necessary at the time of actual operation control of the medium conveyance. In addition, the timer value of the jam detection time for the normal sensors 31 and 34 is set. The timer value for the sensor 31 is set to an initial value T1 because the sensors 32 and 33 are located at the rear position in the traveling direction of the medium on the transport path. However, the timer value for sensor 34 is
Since both Nos. 2 and 33 are located in front of the sensor 34 on the transport path in the direction of travel of the medium, and both have failed, the total value of T2 + T3 + T4 is set (SB6).

Next, a display (in this case, "single-sheet feeding mode") indicating that the second transport control is to be performed is made on the operation panel 25, the internal flags are set to be in an executable state, and a certificate issuance instruction of the upper apparatus is made. The state is changed to a waiting online state (SB7). When the sensor 32 is in the ON state, the sensor 33 is determined to be faulty (SB2). At this time, since it is necessary at the time of actual operation control of the medium conveyance similarly to the above, the sensor fault flag (in this case, the sensor 33 Failure flag). In addition, the timer value of the jam detection time for the normal sensors 31 and 34 is set. The timer value for the sensor 32 is set to an initial value T2 since the sensor 33 is located at the rear position in the traveling direction of the medium on the transport path. However, the timer value for the sensor 34 is equal to T since the sensor 33 is located at the front position in the medium traveling direction on the transport path of the sensor 34.
The sum of 3 + T4 is set (SB3). Similarly, the timer value for the sensor 31 is equal to the initial value T since the sensor 33 is located at the rear position in the traveling direction of the medium on the transport path.
1 is set (SB4).

Next, a display indicating that the second transport control is to be performed (in this case, "intermittent feeding mode") is performed on the operation panel 25, the internal flags are set to be in an executable state, and the higher-level apparatus waits for a certificate issuing instruction. Online state (SB5).

In SB2, when the sensor 32 is on, it is determined that the sensor 32 has failed. At this time, the sensor failure flag (in this case, the sensor 32 failure flag) is turned on as described above. In addition, a timer value of the jam detection time for the normal sensors 31, 33 and 34 is set. As the timer value for the sensor 31, an initial value T1 is set. The timer value for the sensor 33 is set to the total value of T2 + T3 because the sensor 33 is located at the front position in the traveling direction of the medium on the transport path of the sensor 32. As the timer value for the sensor 34, an initial value T4 is set (SB8).

FIG. 9 is a flow chart (1) for controlling the feeding of a medium during online processing.

Here, the operation of the apparatus when a command is received from a higher-level apparatus will be mainly described focusing on medium feeding control.

First, when the apparatus is in the ready state, it becomes possible to receive a command from the host apparatus. When a command from the host device is received (SC1), a payout request flag (F) for feeding out one medium stored in the medium storage case 20 is issued.
DR) is turned on (SC2). Generally, a command for printing a plurality of sheets (N sheets) is issued by a single command from a host device.
Here, it is checked whether or not the medium is the last page (S
C3). If it is not the last page, the feed request flag (F
DR) is turned on (SC6), the DFD is turned on to pick up the medium from the medium storage, the drive motor is rotated, and the conveyance path motor is turned on (DM
T → ON) to rotate the conveyance path roller 23, and further to detect the jam, the sensor 31 jam time (Ta
Start 1). Further, the medium flag 1 (MDM1) indicating that the medium is moving toward the sensor 31 is turned on (SC7).

When the medium is not detected by the sensor 31, the flow jumps to the next medium feeding control flow (2) (SC8). When the medium is detected by the sensor 31, it is determined whether or not a timeout has occurred in the sensors 31 to 34. When the timeout has not occurred, the process returns to SC3. When the timeout has occurred, the jam processing is performed. (SC9). When the jam state is detected, "jam" is displayed on the operation panel 25 (SC10). Further, the motor drive (DMT) is turned off to stop the motor (SC
11). Here, when the operator removes the jammed medium (SC12) and presses the reset key, the apparatus returns to the initial state (SC13).

Next, FIG. 10 shows a medium feeding control flow (2) at the time of online processing. The medium fed out onto the transport path 22 by a command from a host device is the medium after the trailing end is detected by the sensor 31. Will be described.

Wait until the medium has passed over the sensor 31 (SD1). When the medium feeding mode is the “continuous feeding mode” when the medium has passed over the sensor 31, the FDR of the medium feeding start signal is turned on, and the next medium is fed from the medium storage (SD3). This “continuous feeding mode” is a flag that is set when all sensors on the transport path are normal. When the medium feeding mode is other than the “continuous feeding mode”, the flow jumps to the certificate printing without turning on the FDR (SD2). The printing on the medium (certificate) is executed (SD4). When the printing of the certificate is completed, the feeding mode is checked again. If the sensor 33 is out of order in the intermittent feeding mode and the sensor 31-34 has timed out, the jam processing is executed, and the sensors 31-34 are executed. Does not occur, when the sensor 32 detects the rear end of the medium, the FDR of the medium feeding start signal is turned on, and the next medium is fed from the medium storage (SD5 to SD9).

FIGS. 11 and 12 show each interrupt processing routine.

Except for the interrupt 5, the interrupt routine here runs independently of the normal processing routine when each sensor detects the leading end of the medium, and sets the parameters and flags to set the timer value. It is for setting or issuing a command to turn on / off the motor drive. Only the interrupt 5 is activated by the sensor 34 detecting the trailing edge of the medium for the final processing of the medium.
(A) This interrupt 1 is activated when the sensor 31 detects the leading end of the medium. When the interrupt 1 is activated, the medium flag 1 (MDM1) is turned off, and the timer 1 (Ta1) for the jam monitoring time is stopped (SE1). When the sensor failure flags 2 and 3 (SDF2, SDF3) are both ON, it indicates that both the sensor 32 and the sensor 33 have failed, and at this time, the jam monitoring time timer 4 (Ta)
4) is activated, the medium flag 4 (MDM4) is turned on, and the interruption is terminated (SE6). Sensor failure flag 2
When (SDF2) is ON, it indicates that the sensor 32 is out of order. At this time, the timer 3 (T
a3) is activated, the medium flag 3 (MDM3) is turned on, and the interruption is terminated (SE3, SE4). When the sensor failure flag 2 (SDF2) is off, the sensor 33
At this time, the timer 2 (Ta2) of the jam monitoring time is started, and the medium flag 2 (MDM) is started.
2) is turned on to end the interrupt (SE3, SE
5). (B) This interrupt 2 is activated when the sensor 32 detects the leading end of the medium. When interrupt 2 is activated,
The medium flag 2 (MDM2) is turned off, and the timer 2 (Ta2) for the jam monitoring time is stopped (SF1). Next, when the sensor failure flag 3 (SDF3) is on, the sensor 3
3 indicates that a failure has occurred. At this time, the timer 4 (Ta4) for the jam monitoring time is started, and the medium flag 4 (MD
M4) is turned on to end the interrupt (SF2, SF
4).

When the sensor failure flag 3 (SDF3) is off, it indicates that the sensor 32 has failed. At this time, the jam monitoring time timer 3 (Ta3) is activated, and the medium flag 3 (MDM3) Is turned on to end the interrupt (SF2, SF3). (C) This interrupt 3 is activated when the sensor 33 detects the leading end of the medium. Interrupt 3
Is activated, the medium flag 3 (MDM3) is turned off, the timer 3 (Ta3) for the jam monitoring time is stopped, the timer 4 (Ta4) for the jam monitoring time is also activated, and the medium flag 4 (MDM4) is reset. Turn on (SG1). Further, when the medium feeding mode is the “intermittent mode” and the sensor 32 is out of order, the FDR of the medium feeding start signal is turned on to feed the next medium from the medium storage (SG
2 to SG4). (D) This interrupt 4 is activated when the sensor 34 detects the leading end of the medium. When the interrupt 4 is activated, the medium flag 4 (MDM4) is turned off, the timer 4 (Ta4) for the jam monitoring time is stopped, and the interrupt processing is terminated (SH1). (E) As described above, this interrupt 5 is activated when the sensor 34 detects the rear end of the medium. When the interrupt 5 is activated, the media flag 4 (MDM
4) is turned off, and only when the jam monitoring medium feeding mode is the “single-sheet feeding mode”, the FDR of the medium feeding start signal is output.
Is turned on, and the next medium is fed out from the medium storage (S
J1-2).

[0039]

As described above, according to the present invention, when an abnormality or a failure of a sensor is detected, the sensor is disconnected and the sensor adjacent to the failed sensor on the front side in the medium traveling direction is disconnected. When a sensor at the leading end of the medium or a sensor on the rear side in the medium traveling direction adjacent to the failed sensor detects the trailing end of the medium, control is performed so as to issue a feeding start timing for instructing feeding of the next medium onto the transport path. Thus, only one medium can be transported between the two good sensors, and stable and reliable medium transport can be realized. In this way, there is no need to stop the device and replace the sensor, and the sensor can be used continuously. In addition, a method of automatically detecting a sensor failure is also provided, so that it is possible to provide a means for continuously using a low-cost device.

[Brief description of the drawings]

FIG. 1 is a block diagram of the present invention.

FIG. 2 is a configuration diagram of an embodiment.

FIG. 3 is a medium feeding control method (1) of the present invention.

FIG. 4 is a medium feeding control method (2) of the present invention.

FIG. 5 is a medium feeding control method (3) of the present invention.

FIG. 6 is a table showing a jam time monitoring timer according to the present invention.

FIG. 7: Sensor failure determination and parameter setting flow (1)

FIG. 8: Sensor failure determination and parameter setting flow (2)

FIG. 9 is a flowchart (1) for controlling the feeding of a medium during online processing.

FIG. 10 is a flowchart (2) of a medium feeding control at the time of online processing.

FIG. 11 shows an interrupt routine (1).

FIG. 12 shows an interrupt routine (2).

[Explanation of symbols]

 1: Main control unit 2: Sensor signal detection unit 3: Sensor failure detection unit 4: Line control unit 5: Jam time monitoring timer 6: Medium feeding timing control unit 20: Medium storage 21: Medium discharge unit 22: Transport path 23 : Transport roller 24: printing unit 25: operation panel 26: medium feeding mechanism unit 31: sensor 31 32: sensor 32 33: sensor 33 34: sensor 34

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3E040 AA01 AA05 BA07 BA20 CA02 DA10 FG12 3F048 AA06 AB03 BA05 BB02 BB08 CC03 CC04 CC11 DA06 DB03 DB07 DB16 DC00 3F343 FA04 FB07 JA01 MA03 MA56 MB04 MB13 MC08 9A001 HH34

Claims (2)

[Claims] 1. A transport path for transporting a medium, three or more sensors for detecting a medium on the transport path, and sensor failure detection means for disconnecting an output of the failed sensor when a sensor failure is detected; A medium feeding mechanism that feeds the medium one by one onto the transport path; and when the sensor failure detection unit detects a sensor failure, a sensor adjacent to the failed sensor on the front side in the medium traveling direction detects the tip of the medium and the failure When a sensor on the rear side in the medium traveling direction adjacent to the detected sensor detects the rear end of the medium, the medium feeding mechanism includes a medium feeding timing control unit that instructs the medium feeding mechanism to feed the next medium onto the transport path. A medium transport device, comprising: 2. When the sensor failure detecting means detects a sensor failure, a predetermined time value of the failed sensor is added to a predetermined time value of medium detection of a sensor adjacent to the failed sensor and located on the front side in the medium traveling direction. 2. The medium transport device according to claim 1, wherein the media transport device is configured to have the following values.