US3812401A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Overtemperature protection system for exhaust gas conversion device
Assignee: Ford Motor Co
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Filing: 1973-04-04
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Granted: 1974-05-21
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Expires: 1993-04-04
Abstract
Abstract An overtemperature protection system for an exhaust gas conversion device, such as a thermal reactor or catalytic converter. Preferably, the system includes a thermocouple temperature sensor located on the exhaust gas conversion device, an electrically-actuated control device for diminishing the operation of the exhaust gas conversion device, and a warning device. Electrical circuitry is provided for actuating the control device in response to the attainment of a first predetermined temperature sensed by the temperature sensor. A warning device may also be actuated at this first predetermined temperature. Additional electrical circuitry provides retained actuation of the control means and warning devices upon the occurrence of a second predetermined temperature sensed by the temperature sensor, the second predetermined temperature being higher than the first predetermined temperature. The thermocouple reference junction is compensated for ambient temperature and electrical circuitry is provided for actuating the control and warning devices upon the occurrence of an open circuit at the temperature-sensing junction of the thermocouple.
Inventors
- 👤 B Radin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:20
CPC Classifications
G; G01; G01K; G01K7/00; G01K7/02; G01K7/026; G01K7/021; G05; G05D; G05D23/00; G05D23/19; G05D23/20; G05D23/22
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
93 words
An overtemperature protection system for an exhaust gas conversion device, said system comprising: means for sensing temperature at a selected location on or in said exhaust gas conversion device; electrically-actuated control means for diminishing the operation of said exhaust gas conversion device; and circuit means for actuating said controL means and for retaining said control means in actuated condition, said circuit means being coupled to said temperature sensing means and to said control means and casuing said retained actuation of said control means at a predetermined temperature sensed by said temperature sensing means.
Claim 2
Dependent Claim
93 words
An overtemperature protection system for an exhaust gas conversion device, said system comprising: means for sensing temperature at a selected location on or in said exhaust gas conversion device; electrically-actuated control means for diminishing the operation of said exhaust gas conversion device; and circuit means for actuating said controL means and for retaining said control means in actuated condition, said circuit means being coupled to said temperature sensing means and to said control means and casuing said retained actuation of said control means at a predetermined temperature sensed by said temperature sensing means.
Claim 3
Dependent Claim
55 words
An overtemperature protection system in accordance with claim 1, wherein said temperature sensing means includes a thermocouple having a temperature-sensing junction for location on or in said exhaust gas conversion device and wherein said circuit means includes means for actuating said control means when the temperature-sensing junction of said thermocouple is in an open-circuit condition.
Claim 4
Dependent Claim
34 words
An overtemperature protection system in accordance with claim 2, wherein said thermocouple includes a reference junction and wherein said circuit means includes means for compensating said thermocouple reference junction for changes in ambient temperature.
Claim 5
Dependent Claim
84 words
An overtemperature protection system in accordance with claim 3, wherein said circuit means includes a differential amplifier having its input terminals coupled to said thermocouple and having its output terminals coupled to said control means, said circuit means further including a fusible element coupled to the output of said differential amplifier, said fusible element being open-circuited in response to a change in the output of said differential amplifier, and the open-circuiting of said fusible element resulting in said retained action of said control means.
Claim 6
Dependent Claim
146 words
An overtemperature protection system for an exhaust gas conversion device, said system comprising: means for sensing temperature at a selected location on or in said exhaust gas conversion device; electrically-actuated control means for diminishing the operation of said exhaust gas conversion device; first circuit means for actuating said control means, said first circuit means being coupled to said temperature-sensing means and to said control means, said first circuit means being responsive at a first predetermined temperature sensed by said temperature-sensing means to cause said actuation of said control means; second circuit means for retaining said control means in actuated condition, said second circuit means being coupled to said temperature-sensing means and to said control means, said second circuit means being responsive at a second predetermined temperature, higher than said first predetermined temperature, sensed by said temperature-sensing means to cause said retained actuation of said control means.
Claim 7
Dependent Claim
146 words
An overtemperature protection system for an exhaust gas conversion device, said system comprising: means for sensing temperature at a selected location on or in said exhaust gas conversion device; electrically-actuated control means for diminishing the operation of said exhaust gas conversion device; first circuit means for actuating said control means, said first circuit means being coupled to said temperature-sensing means and to said control means, said first circuit means being responsive at a first predetermined temperature sensed by said temperature-sensing means to cause said actuation of said control means; second circuit means for retaining said control means in actuated condition, said second circuit means being coupled to said temperature-sensing means and to said control means, said second circuit means being responsive at a second predetermined temperature, higher than said first predetermined temperature, sensed by said temperature-sensing means to cause said retained actuation of said control means.
Claim 8
Dependent Claim
55 words
An overtemperature protection system in accordance with claim 5, wherein said temperature-sensing means includes a thermocouple having a temperature-sensing junction for location on or in said exhaust gas conversion device and wherein said first circuit means includes means for actuating said control means when the temperature-sensing junction of said thermocouple is in an open-circuit condition.
Claim 9
Dependent Claim
35 words
An overtemperature protection system in accordance with claim 6, wherein said thermocouple includes a reference junction and wherein said system further includes circuit means for compensating said thermocouple reference junction for changes in ambient temperature.
Claim 10
Dependent Claim
183 words
An overtemperature protection system in accordance with claim 7, wherein said first circuit means includes a differential amplifier having its input terminals coupled to said thermocouple and having its output coupled to said control means and circuit means for causing the output of said first differential amplifier to change from a first level to a second level upon the sensing by said thermocouple of said first predetermined temperature; wherein said second circuit means includes a second differential amplifier having its input terminals coupled to said thermocouple and having its output coupled to said control means and circuit means for causing the output of said second differential amplifier to change from a first level to a second level upon the sensing by said thermocouple of saiD second predetermined temperature; and wherein said system further includes a fusible element coupled to the output of said second differential amplifier, said fusible element being open-circuited when the output of said second differential amplifier changes from its first level to its second level, said open-circuiting of said fusible element resulting in said retained actuation of said control means.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-05-20 | 1977-11-19 | 1978-05-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-20 | 1981-11-19 | 1982-05-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-20 | 1985-11-19 | 1986-05-21 | $7700.00 | Window Closed / Lapsed |