US4691669A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Engine overheat protection system
Assignee: Individual
•
Filing: 1986-03-17
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Granted: 1987-09-08
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Expires: 2006-03-17
Abstract
Abstract A protection system for internal combustion systems which indicates and alarms the loss of coolant liquid which it detects as a pressure drop at higher temperatures, and then sets off an alarm.
Inventors
- 👤 John H. Otteman
- 👤 John R. Lufkin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 00:06
CPC Classifications
F; F01; F01P; F01P11/00; F01P11/14; H; H01; H01H; H01H35/00; H01H35/24
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
161 words
A coolant system protection system for internal combustion engines comprising; a housing; a normally closed switch means in said housing; coolant fluid pressure sensitive means constructed and arranged to operate said normally closed switch means so that said normally closed switch means remains closed at a lower pressure and opens at a higher pressure; fluid connecting means connecting said coolant fluid pressure sensitive means to detect and respond to coolant fluid pressure; temperature sensitive switch means mounted in said housing, said temperature sensitive switch means being normally open at a lower temperature and closed at a higher temperature; said normally closed switch means and said temperature sensitive switch means being connected in series; alarm means connected in series with said normally closed switch means and temperature sensitive switch means; and electrical power supply means connected to said alarm means; whereby said alarm is activated when fluid pressure is low and temperature is high to indicate coolant loss and higher temperatures concurrently.
Claim 2
Dependent Claim
161 words
A coolant system protection system for internal combustion engines comprising; a housing; a normally closed switch means in said housing; coolant fluid pressure sensitive means constructed and arranged to operate said normally closed switch means so that said normally closed switch means remains closed at a lower pressure and opens at a higher pressure; fluid connecting means connecting said coolant fluid pressure sensitive means to detect and respond to coolant fluid pressure; temperature sensitive switch means mounted in said housing, said temperature sensitive switch means being normally open at a lower temperature and closed at a higher temperature; said normally closed switch means and said temperature sensitive switch means being connected in series; alarm means connected in series with said normally closed switch means and temperature sensitive switch means; and electrical power supply means connected to said alarm means; whereby said alarm is activated when fluid pressure is low and temperature is high to indicate coolant loss and higher temperatures concurrently.
Claim 3
Dependent Claim
53 words
A system according to claim 1 wherein said fluid pressure sensitive means comprises; a flexible diaphragm; a spring loaded piston constructed and arranged to be driven by said diaphragm; said normally closed switch means being operated by said piston; said fluid connecting means connecting said diaphragm to coolant flowing in said coolant system.
Claim 4
Dependent Claim
23 words
A system according to claim 2 in which said coolant fluid pressure sensitive means changes its condition at pressures above approximately 2 psi.
Claim 5
Dependent Claim
23 words
A system according to claim 2 in which said coolant fluid pressure sensitive means changes its condition at pressures above approximately 5 psi.
Claim 6
Dependent Claim
21 words
A system according to claim 2 in which said temperature sensitive swtich means changes its condition at about 160 degrees F.
Claim 7
Dependent Claim
17 words
A system according to claim 1 including latch means latching said alarm means in an activated position.
Claim 8
Dependent Claim
33 words
The device according to claim 6 in which said latch means comprises delay timing means for delaying response of said alarm means to prevent activation by momentary pressure variations even at higher temperatures.
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) | 1990-09-07 | 1991-03-09 | 1991-09-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-09-07 | 1995-03-09 | 1995-09-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-09-07 | 1999-03-09 | 1999-09-08 | $7700.00 | Window Closed / Lapsed |