US3719913A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Viscous strain gage
Assignee: Boeing North American Inc
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Filing: 1969-05-02
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Granted: 1973-03-06
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Expires: 1989-05-02
Abstract
Abstract Metal particles are suspended in an elastomeric compound to produce a conductive strain gage element capable of high elongation which responds with electric signals proportionate to the strain being measured, which strain element is mounted on an elastomeric carrier and encapsulated in a rubbery mass for protection.
Inventors
- 👤 C Dubose
- 👤 H Jessup
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:46
CPC Classifications
G; G01; G01L; G01L1/00; G01L1/20; G01L1/22; G01L1/2287
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
93 words
A viscous strain gage comprising; an electrically insulative elastomeric base portion, a bead of an electrically conductive elastomeric compound, wherein said compound comprises from 50 to 90 weight percent of conductive metal particles, said compound being affixed to said base portion, and extending lengthwise thereof, said base portion and said elastomeric compound having a modulus of elasticity of from 60 psi to 1,000 psi, and electrical connection means attached at two longitudinally displaced points on said conductive compound for conducting a signal indicative of strain on said gage to a strain measuring means.
Claim 2
Dependent Claim
93 words
A viscous strain gage comprising; an electrically insulative elastomeric base portion, a bead of an electrically conductive elastomeric compound, wherein said compound comprises from 50 to 90 weight percent of conductive metal particles, said compound being affixed to said base portion, and extending lengthwise thereof, said base portion and said elastomeric compound having a modulus of elasticity of from 60 psi to 1,000 psi, and electrical connection means attached at two longitudinally displaced points on said conductive compound for conducting a signal indicative of strain on said gage to a strain measuring means.
Claim 3
Dependent Claim
20 words
The invention of claim 1 wherein the conductive elastomeric compound comprises noble metal particles embedded in a latex rubber material.
Claim 4
Independent Claim
122 words
The method of fabricating a low modulus viscous strain gage comprising the steps of; dipping a mandrel into a liquid elastomeric solution for a length of time to form a gage base portion, drying said base portion, mixing a quantity of conductive metal particles into liquid elastomer to form a homogeneous conductive compound, applying a bead of said conductive compound to said gage base portion, attaching a pair of electrical leads to both ends of the bead of said conductive compound with a metal-particle-containing adhesive thereby assuring electrical conductivity and compatability, immersing said gage base, conductive compound, conductive leads and reinforcing adhesive into a liquid elastomeric solution to provide an encapsulating layer, and, heating said strain gage to cure the completed gage.
Claim 5
Independent Claim
122 words
The method of fabricating a low modulus viscous strain gage comprising the steps of; dipping a mandrel into a liquid elastomeric solution for a length of time to form a gage base portion, drying said base portion, mixing a quantity of conductive metal particles into liquid elastomer to form a homogeneous conductive compound, applying a bead of said conductive compound to said gage base portion, attaching a pair of electrical leads to both ends of the bead of said conductive compound with a metal-particle-containing adhesive thereby assuring electrical conductivity and compatability, immersing said gage base, conductive compound, conductive leads and reinforcing adhesive into a liquid elastomeric solution to provide an encapsulating layer, and, heating said strain gage to cure the completed gage.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-05 | 1976-09-04 | 1977-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-05 | 1980-09-04 | 1981-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-05 | 1984-09-04 | 1985-03-06 | $7700.00 | Window Closed / Lapsed |