Patent US4710353A successfully refreshed from Google Patents.
US4710353A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Corrosive liquid leak detecting sensor
Assignee: Junkosha Co Ltd
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Filing: 1986-07-11
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Granted: 1987-12-01
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Expires: 2006-07-11
Abstract
Abstract A detector for detecting leaks of a corrosive liquid such as strong acids or bases is provided comprising a light guide core having a covering which generates heat upon contact with the liquid to the detected, thereby changing the light transmissivity of the light guide, which change can be measured. The covering comprises a porous polymer having a salt within its pores such as an ammonium salt which dissolves in the liquid to be detected and generates heat thereby.
Inventors
- 👤 Satoshi Tanaka
- 👤 Haruo Imaizumi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:50
CPC Classifications
G; G01; G01M; G01M3/00; G01M3/02; G01M3/04; G01M3/16; G01M3/165; G01M3/042; G01M3/045; G01M3/047
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
111 words
A device of manufacture for detecting leaks of a corrosive liquid comprising an elongated optical fiber light guide core having a covering thereover, and light-emitting means and light-receiving means connected to the light guide core, wherein said covering generates heat upon contact with a corrosive liquid to be detected thereby changing the light transmittivity of the light guide core, which change is detected by said light-receiving means, wherein said covering is a porous polymer containing within its pores a material which generates heat upon contact with the corrosive liquid to be detected and wherein the liquid to be detected is alkaline and said material which generates heat is an ammonium salt.
Claim 2
Independent Claim
111 words
A device of manufacture for detecting leaks of a corrosive liquid comprising an elongated optical fiber light guide core having a covering thereover, and light-emitting means and light-receiving means connected to the light guide core, wherein said covering generates heat upon contact with a corrosive liquid to be detected thereby changing the light transmittivity of the light guide core, which change is detected by said light-receiving means, wherein said covering is a porous polymer containing within its pores a material which generates heat upon contact with the corrosive liquid to be detected and wherein the liquid to be detected is alkaline and said material which generates heat is an ammonium salt.
Claim 3
Dependent Claim
16 words
The device of claim 1 wherein said optical fiber light guide care is a glass fiber.
Claim 4
Dependent Claim
12 words
The device of claim 1 wherein said porous polymer is foamed polyurethane.
Claim 5
Dependent Claim
13 words
The device of claim 1 wherein said porous polymer is expanded, porous polytetrafluoroethylene.
Claim 6
Dependent Claim
12 words
The device of claim 1 wherein said ammonium salt is ammonium chloride
Claim 7
Dependent Claim
12 words
The device of claim 1 wherein said ammonium salt is ammonium sulphate.
Claim 8
Dependent Claim
16 words
The device of claim 1 wherein said optical fiber light guide care is a plastic fiber.
Claim 9
Dependent Claim
16 words
The device of claim 7 wherein said optical fiber light guide care is a polymethylmethacrylate fiber.
Claim 10
Dependent Claim
13 words
The device of claim 1 having an outer covering comprising knitted polyester fibers.
Claim 11
Dependent Claim
19 words
The device of claim 9 wherein a water-repellent paint covers a portion of said covering of knitted polyester fibers.
Claim 12
Dependent Claim
23 words
The device of claim 10 wherein said paint is a fluoride powder and adhesive agent in a solvent and containing a vulcanizing agent.
Claim 13
Independent Claim
110 words
A device of manufacture for detecting leaks of a corrosive liquid comprising an elongated optical fiber light guide core having a covering thereover, and light-emitting means and light-receiving means connected to the light guide core, wherein said covering generates heat upon contact with a corrosive liquid to be detected thereby changing the light transmittivity of the light guide core, which change is detected by said light-receiving means, wherein said covering is a porous polymer containing within its pores a material which generates heat upon contact with the corrosive liquid to be detected and wherein the liquid to be detected is acid and said material which generates heat is sodium carbonate.
Claim 14
Independent Claim
110 words
A device of manufacture for detecting leaks of a corrosive liquid comprising an elongated optical fiber light guide core having a covering thereover, and light-emitting means and light-receiving means connected to the light guide core, wherein said covering generates heat upon contact with a corrosive liquid to be detected thereby changing the light transmittivity of the light guide core, which change is detected by said light-receiving means, wherein said covering is a porous polymer containing within its pores a material which generates heat upon contact with the corrosive liquid to be detected and wherein the liquid to be detected is acid and said material which generates heat is sodium carbonate.
Claim 15
Dependent Claim
16 words
The device of claim 12 wherein said optical fiber light guide core is a glass fiber.
Claim 16
Dependent Claim
12 words
The device of claim 12 wherein said porous polymer is foamed polyurethane.
Claim 17
Dependent Claim
13 words
The device of claim 12 wherein said porous polymer is expanded, porous polytetrafluoroethylene.
Claim 18
Dependent Claim
16 words
The device of claim 12 wherein said optical fiber light guide core is a plastic fiber.
Claim 19
Dependent Claim
16 words
The device of claim 16 wherein said optical fiber light guide core is a polymethylmethacrylate fiber.
Claim 20
Dependent Claim
13 words
The device of claim 12 having an outer covering comprising knitted polyester fibers.
Claim 21
Dependent Claim
19 words
The deivce of claim 18 wherein a waterrepellent paint covers a portion of said covering of knitted polyester fibers.
Claim 22
Dependent Claim
23 words
The device of claim 19 wherein said paint is a fluoride powder and adhesive agent in a solvent and containing a vulcanizing agent.
References Cited (Backward Citations)
US4029889A
Cited
US4132540A
Cited
US4300689A
Cited
US4206632A
Cited
US4283250A
Cited
US4404516A
Cited
US4590462A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-11-30 | 1991-06-01 | 1991-12-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-11-30 | 1995-06-01 | 1995-12-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-11-30 | 1999-06-01 | 1999-12-01 | $7700.00 | Window Closed / Lapsed |