US3580078A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermocouple failure indicating device
Assignee: Trane US Inc
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Filing: 1969-04-16
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Granted: 1971-05-25
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Expires: 1989-04-16
Abstract
Abstract A thermocouple for immersion in a bath of molten metal, or other liquid, comprising a closed-ended sheath having crushed ceramic insulation packed therein to thermally insulate certain hot junction wires contained within the sheath. A special auxiliary conductor is arranged within the sheath to energize an alarm circuit should a rupture develop in the sheath wall. Such rupture causes the molten metal to saturate the ceramic and electrically connect with the conductor for developing the alarm signal.
Inventors
- 👤 Douglas James Mackenzie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:55
CPC Classifications
G; G01; G01K; G01K1/00; G01K1/08; G01K7/00; G01K7/02; G01K7/026
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
144 words
A liquid bath temperature-detection thermocouple comprising a closed-ended sheath adapted for immersion within the bath; wires extending within the sheath, said wires being connected together adjacent the sheath closed end to define a hot junction responsive to the liquid temperature; crushed ceramic insulation packed into the sheath around the wires to completely fill the sheath interior space; and sheath-rupture detection means comprising at least one current conductor extending into the sheath in spaced relation to the sheath wall and aforementioned wires, and an external voltage source connected with the conductor; said ceramic insulation being packed around the current conductor to prevent current flow therethrough as long as the sheath is without rupture; said crushed ceramic insulation having a liquid-absorbent character, whereby a rupture in the sheath allows bath liquid to penetrate and saturate the insulation for completing an electric circuit through the aforementioned conductor.
Claim 2
Dependent Claim
144 words
A liquid bath temperature-detection thermocouple comprising a closed-ended sheath adapted for immersion within the bath; wires extending within the sheath, said wires being connected together adjacent the sheath closed end to define a hot junction responsive to the liquid temperature; crushed ceramic insulation packed into the sheath around the wires to completely fill the sheath interior space; and sheath-rupture detection means comprising at least one current conductor extending into the sheath in spaced relation to the sheath wall and aforementioned wires, and an external voltage source connected with the conductor; said ceramic insulation being packed around the current conductor to prevent current flow therethrough as long as the sheath is without rupture; said crushed ceramic insulation having a liquid-absorbent character, whereby a rupture in the sheath allows bath liquid to penetrate and saturate the insulation for completing an electric circuit through the aforementioned conductor.
Claim 3
Dependent Claim
28 words
The thermocouple of claim 1 wherein the conductor extends substantially the entire length of the sheath whereby to detect a rupture at any point along the sheath wall.
Claim 4
Dependent Claim
32 words
The thermocouple of claim 1 wherein the sheath is electrically conductive, said sheath being ground-connected to furnish a current path from the ceramic when the ceramic is saturated with the bath liquid.
Claim 5
Dependent Claim
40 words
The thermocouple of claim 1 wherein the sheath-rupture detection means comprises a second current conductor extending into the sheath in spaced relation to the first current conductor, whereby saturation of the ceramic provides a current path bridging the two conductors.
References Cited (Backward Citations)
US2805272A
Cited
US3453151A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-05-24 | 1974-11-23 | 1975-05-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-24 | 1978-11-23 | 1979-05-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-24 | 1982-11-23 | 1983-05-25 | $7700.00 | Window Closed / Lapsed |