US4894635A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Strain sensor
Assignee: NGK Insulators Ltd
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Filing: 1988-05-24
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Granted: 1990-01-16
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Expires: 2008-05-24
Abstract
Abstract A strain sensor including a ceramic substrate deformable in response to a stress exerted thereon, and an electrically resistive layer formed on the ceramic substrate, so that a strain of the ceramic substrate caused by the stress is detected as a change in a resistance value of the electrically resistive layer. The electrically resistive layer has a composition which includes a dielectric material selected from the group consisting of glasses and ceramics, and at least one principal electrically conductive component in the form of a powder selected from the group consisting of: borides, carbides and nitrides of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo and W; borides of Y, Sc and lanthanide series; BN; B 4 C; BSi; SiC; and Si 3 N 4 .
Inventors
- 👤 Yasuhita Yajima
- 👤 Kaszuyoshi Shitaba
- 👤 Syunzo Mase
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:56
CPC Classifications
G; G01; G01L; G01L9/00; G01L9/0041; G01L9/0051; G01L9/0052; G01L9/0055
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
129 words
A strain sensor including a ceramic substrate deformable in response to a stress exerted thereon, and an electrically resistive layer formed on the ceramic substrate, a strain of the ceramic substrate caused by the stress being detected as a change in a resistance value of the electrically resistive layer, wherein the improvement comprises: said electrically resistive layer having a composition which includes a dielectric material selected from the group consisting of glasses and ceramics, and at least one principal electrically conductive component in the form of a powder selected from the group consisting of: borides, carbides and nitrides and silicates of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo and W; borides of Y, Sc and lanthanide series; BN; B 4 C; SiC; and Si 3 N 4 .
Claim 2
Dependent Claim
129 words
A strain sensor including a ceramic substrate deformable in response to a stress exerted thereon, and an electrically resistive layer formed on the ceramic substrate, a strain of the ceramic substrate caused by the stress being detected as a change in a resistance value of the electrically resistive layer, wherein the improvement comprises: said electrically resistive layer having a composition which includes a dielectric material selected from the group consisting of glasses and ceramics, and at least one principal electrically conductive component in the form of a powder selected from the group consisting of: borides, carbides and nitrides and silicates of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo and W; borides of Y, Sc and lanthanide series; BN; B 4 C; SiC; and Si 3 N 4 .
Claim 3
Dependent Claim
28 words
A strain sensor according to claim 1, wherein said ceramic substrate comprises a diaphragm, and a base secured to a periphery of said diaphragm for supporting the diaphragm.
Claim 4
Dependent Claim
48 words
A strain sensor according to claim 1, wherein said composition of said electrically resistive layer is applied by a screen printing technique in the form of a printing ink to a surface of said ceramic substrate, and the applied print ink is fired into the electrically resistive layer.
Claim 5
Dependent Claim
44 words
A strain sensor according to claim 1, wherein said composition of said electrically resistive layer is applied in an unfired state to a surface of a fired body of said ceramic substrate, and the applied unfired composition is fired into the electrically resistive layer.
Claim 6
Dependent Claim
43 words
A strain sensor according to claim 1, wherein said composition of said electrically resisitive layer is applied in an unfired state to a surface of an unfired body of said ceramic substrate, and the applied unfired composition and said unfired body are co-fired.
Claim 7
Dependent Claim
54 words
A strain sensor according to claim 1, wherein said ceramic substrate includes a ceramic diaphragm portion, and said electrically resistive layer is formed on a portion of at least one of opposite major surfaces of said ceramic substrate which has a higher degree of strain sensitivity to the stress applied, than another portion thereof.
References Cited (Backward Citations)
US4071838A
Cited
US4311980A
Cited
US4522067A
Cited
US4511877A
Cited
US4462018A
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US4695504A
Cited
US4771639A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-01-15 | 1993-07-17 | 1994-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-15 | 1997-07-17 | 1998-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-15 | 2001-07-17 | 2002-01-16 | $7700.00 | Window Closed / Lapsed |