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US4430518A Expired / Lapsed US ⏱️ 0.0 years remaining

Protecting tube for thermocouple

Assignee: Denka Co Ltd
•
Filing: 1981-11-30
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Granted: 1984-02-07
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Expires: 2001-11-30
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Abstract

Abstract A protecting tube for a thermocouple is provided which comprises an outer shell made of a tubular molded body of boron nitride and an inner sheath made of a tubular molded body of ceramics.

Inventors

  • 👤 Takashi Nakajima
  • 👤 Fujio Matsui

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 13:21
CPC Classifications
G; G01; G01K; G01K1/00; G01K1/08; G01K1/10; G01K1/105

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 122 words
A protecting tube for a platinum/platinum-rhodium thermocouple, comprising an outer shell made of a tubular molded body of boron nitride having a density of 1.7 to 2.2 g/cm 3 and an inner sheath made of a tubular molded body of ceramics, said outer shell and said inner sheath having one end opening to define a port through which the thermocouple is inserted, said outer shell being formed by the steps of molding boron nitride powders at a temperature of higher than 1500° C. while applying a pressure of from 100 to 500 kg/cm 2 to form a molded block of boron nitride, cutting out a rod having desired dimensions and shape from said block, and boring said rod to form a cylinder.
Claim 2
Dependent Claim 122 words
A protecting tube for a platinum/platinum-rhodium thermocouple, comprising an outer shell made of a tubular molded body of boron nitride having a density of 1.7 to 2.2 g/cm 3 and an inner sheath made of a tubular molded body of ceramics, said outer shell and said inner sheath having one end opening to define a port through which the thermocouple is inserted, said outer shell being formed by the steps of molding boron nitride powders at a temperature of higher than 1500° C. while applying a pressure of from 100 to 500 kg/cm 2 to form a molded block of boron nitride, cutting out a rod having desired dimensions and shape from said block, and boring said rod to form a cylinder.
Claim 3
Dependent Claim 28 words
A protecting tube according to claim 1, wherein said ceramics is selected from the group consisting of alumina, beryllia, silicon nitride, zirconia, silica, thoria, yttria and mixtures thereof.
Claim 4
Dependent Claim 42 words
A protecting tube according to claim 1, wherein said inner sheath is formed by sintering ceramics powders with or without a binder at a temperature of higher than 1000° C. while applying a pressure of from 50 to 500 kg/cm 2 .
Claim 5
Dependent Claim 42 words
A protecting tube according to claim 1, wherein said inner sheath is formed by hot-pressing ceramics powders with or without a binder at a temperature of higher than 1000° C. while applying a pressure of from 50 to 500 kg/cm 2 .
Claim 6
Dependent Claim 22 words
In the combination of a platinum/platinum-rhodium thermocouple and a protecting tube therefor, the improvement comprising a protecting tube according to claim 1.
Claim 7
Dependent Claim 22 words
In the combination of a platinum/platinum-rhodium thermocouple and a protecting tube therefor, the improvement comprising a protecting tube according to claim 2.
Claim 8
Dependent Claim 22 words
In the combination of a platinum/platinum-rhodium thermocouple and a protecting tube therefor, the improvement comprising a protecting tube according to claim 3.
Claim 9
Dependent Claim 22 words
In the combination of a platinum/platinum-rhodium thermocouple and a protecting tube therefor, the improvement comprising a protecting tube according to claim 4.

References Cited (Backward Citations)

US2697734A Cited
US4060095A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-02-06 1987-08-08 1988-02-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-02-06 1991-08-08 1992-02-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-02-06 1995-08-08 1996-02-07 $7700.00 Window Closed / Lapsed

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