Press residual life monitor

• US 6,594,597 B1
• Filed: 10/04/2000
• Issued: 07/15/2003
• Est. Priority Date: 10/15/1999
• Status: Active Grant

• Current Assignee: The Minster Machine Company (Nidec Corporation)
• Original Assignee: The Minster Machine Company (Nidec Corporation)
• Inventors: Schoch, Daniel A.
• Primary Examiner(s): Barlow, John
• Assistant Examiner(s): LAU, TUNG S
• Application Number:
  US09/679,002
• Time in Patent Office: 1,014 Days
• Field of Search: 417/63, 702/81, 702/8, 735/79, 736/61, 735/70, 192/103, 705/36, 705/14, 364/550, 513/25
• US Class Current: 702/81
• CPC Class Codes: B30B 15/28 Arrangements for preventing distortion of, or damage to, presses or parts thereof
• CPC Class Codes: G05B 23/0232 based on qualitative trend analysis, e.g. system evolution
• CPC Class Codes: G05B 23/0283 Predictive maintenance, e.g. involving the monitoring of a system and, based on the monitoring results, taking decisions on the maintenance schedule of the monitored system; Estimating remaining useful life [RUL] preventive maintenance, i.e. planning maintenance according to the available resources without monitoring the system G06Q10/06
• CPC Class Codes: G07C 3/00 Registering or indicating the condition or the working of machines or other apparatus, other than vehicles

Abstract

A method and apparatus for determining the original warranty and extended warranty for a mechanical device. A value indicative of the severity of the use of a mechanical device is utilized to develop a value of original warranty and a value of extended warranty. Extended warranty information may additionally be used to offer an automatic buyback of the mechanical device.

Claims

1. A method of generating a measure of warranty for a mechanical device, comprising:

developing an indicator of use severity for the mechanical device;

determining the maximum recommended use severity level, the maximum recommended use severity level being a use severity level above which the mechanical device should not be operated;

determining the hours of operation for the original warranty period;

providing a computational device; and

computing the original warranty use severity life for the mechanical device based upon the maximum recommended use severity level and hours of operation for the original warranty period.

2. The method of claim 1, further comprising:

generating a cumulative measure of actual production use severity of the mechanical device for the original warranty period; and

computing the extended warranty use severity life remaining at the conclusion of the original warranty period for the mechanical device based upon the original warranty use severity life and the cumulative measure of actual production use severity.

3. The method of claim 2, wherein said step of generating a cumulative measure of the actual production use severity of the mechanical device comprises:

determining a count quantity for the mechanical device;

monitoring the actual production use severity of the mechanical device;

monitoring the count quantity of the mechanical device;

tabulating actual production use severity versus count quantity; and

computing a cumulative actual production use severity value for the original warranty period based upon the tabulated use severity versus count quantity values.

4. The method of claim 3, further comprising:

calculating a measure of the extended warranty.

5. The method of claim 4, further comprising:

offering an automatic buyback of the mechanical device if the measure of extended warranty is above a predetermined measure.

6. The method of claim 4, further comprising:

setting the measure of the extended warranty to zero if the monitored use severity of the mechanical device exceeds the maximum recommended use severity level.

7. The method of claim 4, wherein said step of calculating a measure of the extended warranty comprises:

computing the average actual production use severity for the original warranty period; and

computing the extended warranty period based upon the extended warranty use severity life remaining at the conclusion of the original warranty period for the mechanical device and the average actual production use severity for the original warranty period.

8. The method of claim 4, wherein said step of calculating a measure of the extended warranty comprises:

computing actual production use severity over discrete time intervals of equal length based upon the average actual production use severity measured over the discrete time interval and the length of the time interval;

computing the extended warranty remaining at the conclusion of the first discrete time interval based upon the extended warranty use severity life and the actual production use severity for the first discrete time interval; and

computing the extended warranty remaining at the conclusion of each discrete time interval based upon the previously determined extended warranty remaining at the conclusion of the previous discrete time interval and the use is severity for each discrete time interval.

9. A method of generating a measure of warranty for a mechanical press, comprising:

determining the maximum recommended vibration severity level, the maximum recommended vibration severity level being a use severity level above which the mechanical press should not be used;

determining the hours of operation for the original warranty period;

providing a computational device; and

computing the original warranty vibration severity life based upon the maximum recommended vibration severity level and hours of operation for the original warranty period.

10. The method of claim 9, further comprising:

generating a cumulative measure of the actual production vibration severity use of the mechanical press for the original warranty period; and

computing the extended warranty vibration severity life remaining at the conclusion of the original warranty period for the mechanical press based upon the original warranty vibration severity life and the cumulative measure of actual production vibration severity.

11. The method of claim 10, wherein said step of generating a cumulative measure of the actual production vibration severity use of a mechanical press comprises:

determining a count quantity for the mechanical press;

monitoring the actual production vibration severity of the mechanical press;

monitoring the count quantity of the press;

tabulating actual production vibration severity versus count quantity; and

computing a cumulative actual production vibration severity value for the original warranty period based upon the tabulated vibration severity versus count quantity values.

12. The method of claim 11, further comprising:

providing a sensor security device for verifying that the sensed vibration severity level is valid for the press.

13. The method of claim 11, further comprising:

setting run time as the count quantity for the mechanical press;

providing a crank shaft sensor for detecting the crankshaft rpm of the press so that it may be compared with the sensed run time and vibration severity to provide a backup check to ensure that the devices which monitor the vibration severity and run time of the press have not been altered or disconnected.

14. The method of claim 11, further comprising:

providing a tamper proof enclosure for the computational device.

15. The method of claim 10, wherein said step of generating a cumulative measure of the actual production vibration severity use of a mechanical press further comprises:

generating a unique press vibration severity/reliability zone chart;

generating vibration severity zone life acceleration factors corresponding to the zones of the vibration severity/reliability zone chart;

comparing the monitored actual production vibration severity to the vibration severity/reliability zone chart to determine in which reliability zone the press is operating;

associating the monitored actual production vibration severity with the appropriate zone life acceleration factor;

computing a weighted actual production vibration severity value using the monitored actual production vibration severity and the appropriate vibration severity zone life acceleration factor;

recording weighted actual production vibration severity values vs. time; and

computing a cumulative actual production vibration severity value using the weighted actual production vibration severity values vs. time.

16. The method of claim 15, wherein said step of generating a unique press vibration severity/reliability zone chart comprises:

running a press through a plurality of continuously recurring cycles;

monitoring and recording the speed of the press;

monitoring and recording the load exerted by the press;

monitoring and recording vibration severity magnitude velocity induced in the press utilizing a vibration sensor, for example, an accelerometer means attached to the press;

plotting the recorded vibration severity magnitude on a load vs. speed graph;

varying the speed and the load of the press and repeating the previous steps until a plurality of vibration magnitudes are recorded; and

defining curves of equal vibration severity magnitudes on said graph to divide the graph into a plurality of zones representing different vibration magnitudes.

17. The method of claim 15, further comprising:

calculating a measure of the extended warranty.

18. The method of claim 17, further comprising:

offering an automatic buyback of the mechanical press if the measure of extended warranty is above a predetermined measure.

19. The method of claim 17, further comprising:

setting the measure of the extended warranty to zero if the monitored vibration severity of the mechanical press exceeds the maximum recommended vibration severity level.

20. The method of claim 17, wherein said step of calculating a measure of the extended warranty comprises:

computing the average weighted actual production vibration severity for the original warranty period; and

computing the extended warranty period based upon the extended warranty vibration severity life remaining at the conclusion of the original warranty period for the mechanical press and the average weighted actual production vibration severity for the original warranty period.

21. The method of claim 17, wherein said step of calculating a measure of the extended warranty comprises:

computing vibration severity use over discrete time intervals of equal length based upon the average actual production vibration severity measured over the discrete time interval and the length of the time interval;

computing the extended warranty remaining at the conclusion of the first discrete time interval based upon the extended warranty vibration severity life and the actual production vibration severity use for the first discrete time interval; and

computing the extended warranty remaining at the conclusion of each discrete time interval based upon the previously determined extended warranty remaining at the conclusion of the previous discrete time interval and the vibration severity use for each discrete time interval.

22. An apparatus for monitoring the residual warranty of a mechanical press, comprising:

a counter for sensing a count quantity for the press;

a vibration sensor, for sensing vibration severity values, said vibration sensor attached to the press; and

a vibration severity life monitor for tabulating the vibration severity values and information associated with the vibration severity values versus time, said vibration severity life monitor stores an original warranty value and computes a value of extended warranty based on the tabulated and stored information, said vibration severity life monitor communicatively connected to said run time sensor and said vibration sensor.

23. The apparatus as recited in claim 22, wherein said counter is a run time sensor for sensing whether the press is operating.

24. The apparatus as recited in claim 22, further comprising:

a sensor security device, for receiving the vibration severity values from said vibration sensor, said sensor security device determining whether the sensed vibration severity level is within an acceptable range for the press, said sensor security device communicatively connected to said vibration sensor, for example, an accelerometer and said vibration severity life monitor.

25. The apparatus as recited in claim 22, further comprising:

a zone factor device for storing a vibration severity zone chart associated with the press and a plurality of zone life acceleration factors corresponding to a plurality of vibration severity zones which form a part of said vibration severity zone chart, said zone factor device communicatively connected to said vibration sensor, and to said vibration severity life monitor.

26. The apparatus as recited in claim 22, further comprising:

a crankshaft sensor for detecting a crankshaft rpm value for the press.

27. The apparatus as recited in claim 22, further comprising:

a display device for displaying information tabulated, stored and computed in said vibration severity life monitor, said display device communicatively connected to said vibration severity life monitor.

28. The apparatus as recited in claim 22, wherein said vibration sensor, comprises:

an accelerometer.

29. The apparatus as recited in claim 22, wherein said vibration severity life monitor comprises:

a microprocessor.

30. The apparatus as recited in claim 22, further comprising:

a first tamper proof housing, said first tamper proof housing surrounding said vibration severity life monitor.

31. The apparatus as recited in claim 24, further comprising:

a second tamper proof housing, said second tamper proof housing surrounding said sensor security device.

32. The apparatus as recited in claim 25, wherein said zone factor device comprises:

a microprocessor.