Patent US3930221A successfully refreshed from Google Patents.
US3930221A
Expired / Lapsed
US
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Exhaust backpressure warning system
Assignee: Individual
•
Filing: 1973-03-09
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Granted: 1975-12-30
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Expires: 1993-03-09
Abstract
Abstract A warning system comprises a pressure switch operably connected to the exhaust system of an internal combustion engine and activating a warning signal upon the occurrence of an abnormally high pressure in the exhaust system.
Inventors
- 👤 Frank Thing
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:52
CPC Classifications
F; F02; F02B; F02B77/00; F02B77/08; Y; Y10; Y10T; Y10T137/00; Y10T137/8158; Y10T137/8326
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
66 words
An exhaust backpressure warning system for an internal combustion engine comprising: an exhaust system; a pressure sensor operably connected with said exhaust system and responsive to abnormally high pressure within said exhaust system; and a signal device activated by said sensor and positioned near the normal operating station of said engine to alert the operator thereof of an abnormally high pressure condition in said exhaust system.
Claim 2
Dependent Claim
66 words
An exhaust backpressure warning system for an internal combustion engine comprising: an exhaust system; a pressure sensor operably connected with said exhaust system and responsive to abnormally high pressure within said exhaust system; and a signal device activated by said sensor and positioned near the normal operating station of said engine to alert the operator thereof of an abnormally high pressure condition in said exhaust system.
Claim 3
Dependent Claim
62 words
The structure according to claim 1 wherein said exhaust system has more than one exhaust manifold communicating with a single tail pipe: each of said exhaust manifolds having a duct in communication therewith and operably connected to the pressure sensor; each of said ducts having a one way valve therein whereby a fluid in said duct can flow only toward said sensor.
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) | 1978-12-29 | 1979-06-30 | 1979-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-29 | 1983-06-30 | 1983-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-29 | 1987-06-30 | 1987-12-30 | $7700.00 | Window Closed / Lapsed |