Fault diagnosis apparatus

• US 20050050423A1
• Filed: 07/13/2004
• Published: 03/03/2005
• Est. Priority Date: 07/14/2003
• Status: Active Grant

• Current Assignee: Fuji Xerox Company Limited (Xerox Holdings Corp.)
• Original Assignee: Fuji Xerox Company Limited (Xerox Holdings Corp.)
• Inventors: Satonaga, Tetsuichi, Uwatoko, Koki, Yasukawa, Kaoru, Adachi, Koji, Nakagawa, Eigo, Yamada, Norikazu
• Granted Patent: US 7,174,264 B2
• Time in Patent Office: Days
• US Class Current: 714/742
• CPC Class Codes: B41J 29/38 Drives, motors, controls or automatic cut-off devices for the entire printing mechanism

Abstract

A fault diagnosis section activates a driving compornent alone, measures an operation state signal and a paper passage time, and stores feature values (Vm, σv, Tqs, σts) extracted as a determination reference in a storage medium. A paper passage fault determination section determines whether or not a fault has arisen on the basis of the paper passage time when an apparatus is under normal operating conditions. A diagnosis target block determination section determines an order to operate a detail fault diagnosis when it is determined that there is a plurality of diagnosis target blocks. When the driving compornent is activated alone under actual operation conditions, the operation state signal Vf is obtained, and an operation state fault determination section conducts diagnosis on whether or not a fault has arisen on the driving compornent and a state of the fault, and whether or not a fault has arisen on other power transmission compornents and a nature of the fault with reference to the feature values as the determination reference on the basis of a degree of deviation from a normal range.

Claims

1. A fault diagnosis apparatus for diagnosing a fault that occurs in an apparatus having a drive mechanism including a plurality of elements that include a driving compornent activated by current supply and a power transmission compornent that transmits a driving force of the driving compornent to another compornent, comprising:

a first signal detection unit that detects a first signal indicating an operation state of the drive mechanism within a predetermined period; and

a fault diagnosis unit that executes a fault diagnosis on each element of the drive mechanism based on a deviation of the first signal detected by the first signal detection unit from a normal range.

2. The fault diagnosis apparatus according to claim 1, wherein

the drive mechanism includes a plurality of driving compornents and a signal generation unit that generates a control signal capable of switching the plurality of driving compornents on and off individually,

the first signal detection unit includes a detection compornent used in common for the plurality of driving compornents by which the first signal is detected in a case where the signal generation unit controls one of the driving compornent to be on, and

the fault diagnosis unit executes the fault diagnosis on the plurality of elements including the plurality of driving compornents respectively based on the first signal of the plurality of driving compornents detected by the first signal detection unit in a state where the signal generation unit switches one of the plurality of driving compornents on.

3. The fault diagnosis apparatus according to claim 1, wherein

the fault diagnosis unit extracts a feature value adapted to execute the fault diagnosis based on the first signal detected by the first signal detection unit, and executes the fault diagnosis based on the feature value and a standard feature value indicating the normal range of the first signal.

4. The fault diagnosis apparatus according to claim 1, wherein

the fault diagnosis unit compares the first signal with pre-first signals that are previously obtained on each element of the plurality of elements in a state where the plurality of elements has no faults to determine which signal is corresponding to the first signal among the pre-first signals to specify which element has the fault or details of the fault.

5. The fault diagnosis apparatus according to claim 1, wherein

the first signal detection unit includes a current detection unit that detects a signal indicating a operation current applied to the driving compornent as the first signal.

6. The fault diagnosis apparatus according to claim 1, wherein

the first signal detection unit includes a vibration detection unit that detects a signal indicating a vibration occurring in the drive mechanism as the first signal.

7. The fault diagnosis apparatus according to claim 1, wherein

the drive mechanism is used for a transport system for transporting a transported object, and

the first signal detection unit includes a timing detection unit including a plurality of detection units that detects a passage of the transported object and a measurement unit that measures a transporting timing and a transporting time of the transported object as the first signal based on a detection signal obtained by the plurality of detection units.

8. The fault diagnosis apparatus according to claim 1, wherein

the fault diagnosis unit diagnoses the power transmission compornent that transmits the driving force of the driving compornent activated by current supply to another compornent which does not receive current supply in a case where the first signal is out of the normal range.

9. The fault diagnosis apparatus according to claim 1, wherein

the first signal detection unit includes a current detection unit that detects a signal indicating a operation current applied to the driving compornent as the first signal and a vibration detection unit that detects a signal indicating a vibration occurring in the drive mechanism as the first signal, and

the fault detection unit executes the fault diagnosis on the power transmission compornent that transmits the driving force of the driving compornent activated by current supply to another compornent by multidimensionally analyzing the operation current detected by the current detection unit and the vibration detected by the vibration detection unit whether these are in the corresponding normal range or not respectively.

10. The fault diagnosis apparatus according to claim 1, wherein

the drive mechanism includes a plurality of drive mechanisms,

the first signal detection unit includes a second signal detection unit that detects a second signal indicating an operation state of each drive mechanism on a normal operation state, and

the fault diagnosis unit includes a second determination unit that determines whether the drive mechanism has a fault or not based on the second signal detected by the second signal detection unit and a first determination unit that executes the fault diagnosis on each elements in the drive mechanism determined that the drive mechanism has a fault by the second determination unit.

11. The fault diagnosis apparatus according to claim 1, wherein

the fault diagnosis unit includes a forecast unit that forecasts a fault by comparing the first signal detected by the first signal detection unit with the normal range of the first signal.

12. The fault diagnosis apparatus according to claim 11, wherein

the first signal detection unit detects the first signal more than once, and

the forecast unit forecasts a fault by comparing a distribution of the first signal based on the first signal detected by the first signal detection unit more than once with a distribution indicating the normal range of the first signal.

23. The fault diagnosis apparatus according to claim 1, further comprises a notifying unit that notifies information of the fault diagnosis to a customer.

24. The fault diagnosis apparatus according to claim 1, wherein the fault diagnosis unit executes the fault diagnosis based on an average value and a standard deviation indicating the normal range.

25. The fault diagnosis apparatus according to claim 1, wherein the fault diagnosis unit executes the fault diagnosis by comparing a value that each sampling data obtained by digitizing the first signal is raised to the second power and integrated with the normal range.

26. The fault diagnosis apparatus according to claim 25, wherein

the first signal detection unit obtains the first signal more than once,

the fault diagnosis unit obtains a plurality of values that each sampling data obtained by digitizing the first signal is raised to the second power and integrated, and calculates an average value and a standard deviation based on the plurality of values, and executes the fault diagnosis by comparing the average value and the standard deviation with an average value and a standard deviation indicating the normal range.

27. The fault diagnosis apparatus according to claim 1, wherein the fault diagnosis unit determines to be normal in case where a value of the first signal is in a range of an average value±

(a standard deviation×

3) that indicates the normal range.

28. The fault diagnosis apparatus according to claim 23, wherein the notifying unit notifies at least one of a fault part, a status of a fault and a detail of a diagnosis with the first signal detected by the first signal detection unit to a customer.

13. A fault diagnosis apparatus for diagnosing a fault that occurs in an apparatus having a plurality of drive mechanisms each including a driving compornent activated by current supply and a power transmission compornent that transmits a driving force of the driving compornent to another compornent which does not receive current supply, comprising:

a second signal detection unit that detects a second signal indicating an operation state of each drive mechanism on a normal operation state;

a first signal detection unit that detects a first signal indicating an operation state of each element of each drive mechanism within a predetermined period in a state where each drive mechanism individually activates;

a second determination unit that determines whether the drive mechanism has a fault or not based on the second signal detected by the second signal detection unit; and

a fault diagnosis unit that executes the fault diagnosis on each elements in the drive mechanism determined that the drive mechanism has a fault by the second determination unit.

14. The fault diagnosis apparatus according to claim 13, wherein

the drive mechanism is used for a transport system for transporting a transported object,

the second signal detection unit includes a timing detection unit including a plurality of detection units that detects a passage of the transported object, and a measurement unit that measures a transporting timing and a transporting time of the transported object as the first signal based on a detection signal obtained by the plurality of detection units,

the first signal detection unit that detects the first signal indicating the operation state of each element of the drive mechanism includes at least one of a current detection unit that detects a signal indicating a operation current applied to the driving compornent as the first signal and a vibration detection unit that detects a signal indicating a vibration occurring in the drive mechanism as the first signal,

the second determination unit determines a drive mechanism to be subjected to the fault diagnosis based on the transporting timing and the transporting time detected by the timing detection unit,

the fault diagnosis unit includes a first determination unit that executes the fault diagnosis on each elements in the drive mechanism determined that the drive mechanism has a fault by the second determination unit, and

the first determination unit executes the fault diagnosis on the drive mechanism determined by the second determination unit based on the operation current obtained by the current detection unit or the vibration obtained by the vibration detection unit.

15. The fault diagnosis apparatus according to claim 14, wherein

the second determination unit determines an order to execute the fault diagnosis on each drive mechanism in a case where the second determination unit determines the plurality of drive mechanisms to be subjected to the fault diagnosis, and

the first determination unit executes the fault diagnosis on the plurality of drive mechanisms determined by the second determination unit according to the order determined by the second determination unit.

20. The fault diagnosis apparatus according to claim 13, further comprises

a storage unit that stores information indicating the normal range obtained based on the first signal detected by the first signal detection unit in a state where the apparatus has no faults, wherein

the fault diagnosis unit reads out the information indicating the normal range from the storage unit to execute the fault diagnosis.

21. The fault diagnosis apparatus according to claim 20, wherein the storage unit stores information indicating the normal range of each drive mechanism obtained based on the first signal detected by the first signal detection unit in a state where the plurality of drive mechanisms activates individually.

22. The fault diagnosis apparatus according to claim 20, wherein the storage unit stores information indicating the normal range obtained based on the first signal detected by the first signal detection unit in a state where the apparatus including the drive mechanism has no faults at a shipment of the apparatus or after a replacement of the elements.

16. A fault diagnosis apparatus for diagnosing a fault that occurs in an apparatus having a drive mechanism including a plurality of elements that includes a driving compornent activated by current supply and a power transmission compornent that transmits a driving force of the driving compornent to another compornent, comprising:

a first signal detection unit that detects a first signal indicating an operation state of the drive mechanism more than once,

a fault diagnosis unit that forecasts a fault of the plurality of elements by comparing a distribution of the first signal obtained based on the first signal detected by the first signal detection unit more than once with a distribution indicating a normal range of the first signal.

17. The fault diagnosis apparatus according to claim 16, wherein

the first signal detection unit detects the first signal more than once on a regular basis, and

the fault diagnosis unit forecasts a fault on a regular basis.

18. The fault diagnosis apparatus according to claim 16, wherein

the drive mechanism is used for a transport system for transporting a transported object,

the first signal detection unit includes a timing detection unit including a plurality of detection units that detects a passage of the transported object, and a measurement unit that measures a transporting timing and a transporting time of the transported object more than once as the first signal based on a detection signal obtained by the plurality of detection units, and

the fault diagnosis unit forecasts a fault by comparing a distribution of the transporting timing and the transporting time of the transported object obtained based on the transporting timing and the transporting time detected by the timing detection unit more than once with a distribution indicating the normal range of the transporting timing and the transporting time.

19. The fault diagnosis apparatus according to claim 18, wherein

the drive mechanism includes a roll compornent that moves the transported object to a predetermined direction by torque, and

the fault diagnosis unit forecasts a fault of the roll compornent.