US4608866A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Small component helium leak detector
Assignee: Lockheed Martin Corp
•
Filing: 1985-03-13
•
Granted: 1986-09-02
•
Expires: 2005-03-13
Abstract
Abstract A small component leak detector is provided having (i) a vacuum chamber for receiving test objects, (ii) a cryogenic pump, and (iii) a mass detector. The cryogenic pump is capable of entrapping a purge carrier gas, such as nitrogen, but not entrapping a detecting gas, such as helium. The purge carrier gas is entrapped by the cryogenic pump and the mass detector detects any helium emitting from the test object. The process of detecting leaks using the foregoing apparatus in conjunction with a purge carrier gas, such as nitrogen, is also disclosed and claimed. The apparatus and process are especially designed for detecting leaks in small components, such as the hermetic seals of electronic components.
Inventors
- 👤 Lyle E. Bergquist
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:19
CPC Classifications
G; G01; G01M; G01M3/00; G01M3/02; G01M3/04; G01M3/20; G01M3/202
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
74 words
A leak detector for sensing a test gas leaking from a test object comprising: a vacuum chamber for receiving the test object which has been contacted by the test gas, a cryogenic pump connected to said vacuum chamber, said cryogenic pump having means for entrapping a purge carrier gas but not entrapping the test gas, and a mass detector connected to said vacuum chamber for detecting the test gas leaked from the test object.
Claim 2
Dependent Claim
74 words
A leak detector for sensing a test gas leaking from a test object comprising: a vacuum chamber for receiving the test object which has been contacted by the test gas, a cryogenic pump connected to said vacuum chamber, said cryogenic pump having means for entrapping a purge carrier gas but not entrapping the test gas, and a mass detector connected to said vacuum chamber for detecting the test gas leaked from the test object.
Claim 3
Dependent Claim
21 words
A leak detector as claimed in claim 1 wherein the purge carrier gas is nitrogen and the test gas is helium.
Claim 4
Dependent Claim
26 words
A leak detector as claimed in claim 2 comprising internal connecting passages, said passages and said vacuum chamber forming an internal vacuum passage consisting of metal.
Claim 5
Dependent Claim
30 words
A leak detector as claimed in claim 3 wherein said leak detector has connection means and said connection means consists of metal-to-metal mating flanges, metal gaskets and internal metal passages.
Claim 6
Dependent Claim
28 words
A leak detector as claimed in claim 2 wherein said leak detector comprises an evacuation pump to evacuate the leak detector in preparation of a leak detecting cycle.
Claim 7
Dependent Claim
16 words
A leak detector as claimed in claim 5 wherein said evacuation pump is a turbo pump.
Claim 8
Dependent Claim
25 words
A leak detector as claimed in claim 2 wherein said cryogenic pump is operated at a temperature from about 16° K. to about 22° K.
Claim 9
Dependent Claim
25 words
A leak detector as claimed in claim 7 wherein said cryogenic pump is operated at a temperature from about 18° K. to about 20° K.
Claim 10
Dependent Claim
32 words
A leak detector as claimed in claim 2 wherein said cryogenic pump has a heater, has lead on at least a portion of its interior surfaces and is free of helium-entrapping material.
Claim 11
Dependent Claim
28 words
A leak detector as claimed in claim 1 wherein said vacuum chamber has a volume from about 10 cc to about 300 cc for receiving small electronic components.
Claim 12
Dependent Claim
133 words
A process for detecting a test gas leaked from a test object comprising: providing a vacuum chamber for receiving the test object, providing a cryogenic pump connected to said vacuum chamber which pump is capable of entrapping a purge carrier gas but not capable of entrapping the test gas leaked from the object, providing a mass detector connected to said vacuum chamber for detecting the test gas, purging said vacuum chamber by introducing the purge carrier gas into said vacuum chamber, introducing into said vacuum chamber the test object which has been contacted with the test gas, evacuating the purge carrier gas and any test gas leaked from said test object from the vacuum chamber by said cryogenic pump, and detecting the test gas leaked from the test object by a mass detector.
Claim 13
Dependent Claim
133 words
A process for detecting a test gas leaked from a test object comprising: providing a vacuum chamber for receiving the test object, providing a cryogenic pump connected to said vacuum chamber which pump is capable of entrapping a purge carrier gas but not capable of entrapping the test gas leaked from the object, providing a mass detector connected to said vacuum chamber for detecting the test gas, purging said vacuum chamber by introducing the purge carrier gas into said vacuum chamber, introducing into said vacuum chamber the test object which has been contacted with the test gas, evacuating the purge carrier gas and any test gas leaked from said test object from the vacuum chamber by said cryogenic pump, and detecting the test gas leaked from the test object by a mass detector.
Claim 14
Dependent Claim
20 words
A process as claimed in claim 11 wherein said purge carrier gas is nitrogen and said test gas is helium.
Claim 15
Dependent Claim
27 words
A process as claimed in claim 12 wherein internal connecting passages are provided, said passages and said vacuum chamber forming an internal vacuum passage consisting of metal.
Claim 16
Dependent Claim
27 words
A process as claimed in claim 13 wherein connection means are provided and said connection means consists of metal-to-metal mating flanges, metal gaskets and internal metal passages.
Claim 17
Dependent Claim
23 words
A process as claimed in claim 12 comprising evacuating the vacuum chamber with an evacuation pump in preparation of a leak detecting cycle.
Claim 18
Dependent Claim
15 words
A process as claimed in claim 15 wherein said evacuation pump is a turbo pump.
Claim 19
Dependent Claim
24 words
A process as claimed in claim 12 wherein said cryogenic pump is operated at a temperature from about 16° K. to about 22° K.
Claim 20
Dependent Claim
24 words
A process as claimed in claim 17 wherein said cryogenic pump is operated at a temperature from about 18° K. to about 20° K.
Claim 21
Dependent Claim
31 words
A process as claimed in claim 12 wherein said cryogenic pump has a heater, has lead on at least a portion of its interior surfaces and is free of helium-entrapping material.
Claim 22
Dependent Claim
33 words
A process for detecting leaks as claimed in claim 11 wherein said test objects are small electronic components and said vacuum chamber has a volume from about 10 cc to about 300 cc.
References Cited (Backward Citations)
US3246505A
Cited
US3416359A
Cited
US3690151A
Cited
US3578758A
Cited
US3646804A
Cited
US3769806A
Cited
US3762212A
Cited
US3788096A
Cited
US3824839A
Cited
US3738158A
Cited
US3888111A
Cited
US4154092A
Cited
US4158960A
Cited
US4356721A
Cited
US4487058A
Cited
US4492110A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-09-01 | 1990-03-03 | 1990-09-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-09-01 | 1994-03-03 | 1994-09-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-09-01 | 1998-03-03 | 1998-09-02 | $7700.00 | Window Closed / Lapsed |