Method and apparatus for detecting leaks in sealed packages

• US 5,361,626 A
• Filed: 01/29/1992
• Issued: 11/08/1994
• Est. Priority Date: 01/29/1992
• Status: Expired due to Term

• Current Assignee: United States Surgical Corporation (Medtronic Plc)
• Original Assignee: United States Surgical Corporation (Medtronic Plc)
• Inventors: Colligan, Francis D., Brown, Lloyd S.
• Primary Examiner(s): Williams, Hezron E.
• Assistant Examiner(s): ROSKOS, JOSEPH
• Application Number:
  US07/827,340
• Time in Patent Office: 1,014 Days
• Field of Search: 73/40.7, 73/49.3, 73/45.4, 73/52
• US Class Current: 73/40.7
• CPC Class Codes: G01M 3/20 using special tracer materials, e.g. dye, fluorescent material, radioactive material
• CPC Class Codes: G01M 3/227 for flexible or elastic containers

Abstract

A hydrocarbon leak detector apparatus detects defectively sealed packages by monitoring for the presence of a volatile hydrocarbonaceous substance that leaks from defective packages. The apparatus includes one or more sealable chambers, a vacuum generator pump, a hydrocarbon detector and conduit means for delivering air from the chamber(s) to the hydrocarbon detector.

Claims

1. A method for evaluating integrity of a sealed package comprising:

depositing a volatile hydrocarbonaceous substance within a package;

sealing the package;

placing the package in a sealable chamber;

sealing said chamber;

pulling a vacuum in said chamber after said chamber has been sealed;

maintaining the vacuum in said chamber for a predetermined time period and then allowing gas into said chamber to relieve the vacuum;

sealing said chamber after the vacuum has been relieved; and

monitoring said chamber for the presence of said volatile hydrocarbonaceous substance.

2. A method according to claim 1 further comprising exposing a hydrocarbon detector to at least a portion of the contents of said chamber after said chamber has been sealed and the vacuum relieved.

3. A method according to claim 2 further comprising purging said chamber after said hydrocarbon detector has been exposed to at least a portion of the contents of the chamber.

4. A method according to claim 2 further comprising purging said hydrocarbon detector after said hydrocarbon detector has been exposed to at least a portion of the contents of said chamber.

5. A method according to claim 2 wherein said hydrocarbon detector is a photoionizer.

6. A method according to claim 5 wherein said photoionizer is adapted to activate an alarm when the concentration of volatile hydrocarbonaceous substance exceeds a predefined limit.

7. A method according to claim 6 wherein said predefined limit is about 500 parts per million.

8. A method according to claim 2 wherein said hydrocarbon detector is a gas chromatograph.

9. A method according to claim 8 wherein said gas chromatograph is adapted to activate an alarm when the concentration of volatile hydrocarbonaceous substance exceeds a predefined limit.

10. A method according to claim 9 wherein said predefined limit is about 500 parts per billion.

11. A method according to claim 1 wherein the vacuum is at least about one inch of mercury.

12. A method according to claim 1 wherein the vacuum is from about five to about twenty inches of mercury.

13. A method according to claim 1 wherein the vacuum is maintained for about twenty-five to about thirty-five seconds.

14. A method according to claim 1 wherein said volatile hydrocarbonaceous substance is an organic solvent.

15. A method according to claim 1 wherein said volatile hydrocarbonaceous substance is isopropyl alcohol.

16. A method according to claim 1 wherein an alarm is adapted to be activated when the amount of volatile hydrocarbonaceous substance being monitored exceeds a predefined limit.

17. A method according to claim 1 wherein the sealed package contains surgical sutures.

18. An apparatus for evaluating the integrity of a sealed package which comprises:

(i) a plurality of sealable chambers;

(ii) a vacuum generator pump;

(iii) a hydrocarbon detector; and

(iv) means for selectively delivering gas from any one of said sealable chambers to said hydrocarbon detector.

19. An apparatus according to claim 18 wherein said hydrocarbon detector is a photoionizer.

20. An apparatus according to claim 19 further comprising alarm means adapted to be activated when the concentration of hydrocarbon exceeds a predetermined level.

21. An apparatus according to claim 20 wherein said predetermined level is 500 ppm.

22. An apparatus according to claim 18 wherein said hydrocarbon detector is a gas chromatograph.

23. An apparatus according to claim 22 further comprising alarm means adapted to be activated when the concentration of hydrocarbon exceeds a predetermined level.

24. An apparatus according to claim 23 wherein said predetermined level is 500 ppb.

25. An apparatus according to claim 18 wherein said hydrocarbon detector is adapted to measure an organic solvent.

26. An apparatus according to claim 18 wherein said hydrocarbon detector is adapted to measure isopropyl alcohol.

27. An apparatus according to claim 18 further comprising alarm means adapted to be activated when the concentration of hydrocarbon exceeds a predetermined level.

28. An apparatus according to claim 18 wherein said means for selectively delivering gas is a microprocessor controlled by program means.

29. An apparatus for evaluating the integrity of a sealed package which comprises:

(i) a sealable chamber;

(ii) a vacuum generator pump;

(iii) a gas chromatograph; and

(iv) conduit means for delivering air from said chamber to said gas chromatograph.

30. An apparatus according to claim 29 wherein said gas chromatograph is adapted to measure a volatile hydrocarbonaceous substance.

31. An apparatus according to claim 30 wherein said volatile hydrocarbonaceous substance is isopropyl alcohol.

32. An apparatus according to claim 29 further comprising alarm means adapted to be activated when the concentration of a volatile hydrocarbonaceous substance exceeds a predetermined level.

33. An apparatus according to claim 32 wherein said predetermined level is 500 ppb.