US3704988A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Engine decompression device
Assignee: Victa Ltd
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Filing: 1970-09-03
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Granted: 1972-12-05
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Expires: 1990-09-03
Abstract
Abstract A decompressing device for the firing chamber of an internal combustion engine during only low cranking speed, comprising a venting valve for the chamber, a housing therefor screwed to a port in the chamber, a valve element exposed to compressed gases in the chamber and forced temporarily thereby to a closed condition, and means for damping return opening action of the valve element whereby at and above a predetermined speed of the engine the valve element remains continuously closed.
Inventors
- 👤 William Henry Steele
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:44
CPC Classifications
F; F01; F01L; F01L13/00; F01L13/08
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
137 words
A device for decompressing an internal combustion engine during cranking and automatically progressively restoring compression thereto as the running speed of the engine increases, said device comprising a housing mountable to a port in the engine compression chamber, venting means for the housing for the escape of compressed gases in said chamber, a valve seat in the housing, a valve element positioned and constructed so as to be forced to close upon the valve seat by the compressed gases in, and passing from, the chamber; a fluid chamber in the housing, means for at least partly evacuating fluid from said chamber; a displaceable member forming a wall of said chamber, aNd a valve stem interconnecting said displaceable member and said valve element to hold said valve element closed when said fluid chamber is at least partly evacuated.
Claim 2
Independent Claim
137 words
A device for decompressing an internal combustion engine during cranking and automatically progressively restoring compression thereto as the running speed of the engine increases, said device comprising a housing mountable to a port in the engine compression chamber, venting means for the housing for the escape of compressed gases in said chamber, a valve seat in the housing, a valve element positioned and constructed so as to be forced to close upon the valve seat by the compressed gases in, and passing from, the chamber; a fluid chamber in the housing, means for at least partly evacuating fluid from said chamber; a displaceable member forming a wall of said chamber, aNd a valve stem interconnecting said displaceable member and said valve element to hold said valve element closed when said fluid chamber is at least partly evacuated.
Claim 3
Dependent Claim
26 words
A device according to claim 1, wherein said evacuating means comprises a fluid line for connecting the fluid chamber with the inlet manifold of the engine.
Claim 4
Dependent Claim
13 words
A device according to claim 2, wherein the displaceable member is a diaphragm.
Claim 5
Dependent Claim
88 words
A device according to claim 1, wherein the housing is tubular and threaded at one end for screwing to said port, and the valve seat and the valve element are located at the threaded end of the housing, and further comprising a dashpot located at the opposite end of the housing and containing said fluid chamber, said displaceable member being a piston for the dashpot, and said means for partly evacuating fluid from the dashpot chamber comprising clearance of the piston from the wall of the dashpot chamber.
Claim 6
Dependent Claim
65 words
A device according to claim 4, wherein an intermediate chamber is provided in the tubular housing, an intermediate piston is provided on the valve stem, and the venting means is located between the two chambers of the housing, said intermediate piston being so located on the valve stem that it is accommodated in the intermediate chamber when the valve element is at least partly open.
Claim 7
Independent Claim
193 words
A device for decompressing an internal combustion engine during cranking and automatically progressively restoring compression thereto as the running speed of the engine increases, said device comprising a tubular housing threaded at one end for screwing to a port in the engine compression chamber, a valve seat located at the threaded end of the housing, a valve element having a stem which passes axially through the housing with said valve element protruding from the threaded end of the housing so as to close upon the valve seat with the passage of compressed gases from the engine compression chamber into said housing, venting means in the housing for the escape of compressed gases therein, a fluid chamber at the other end of the housing, a diaphragm on an end of the valve stem and defining one wall of the fluid chamber, and a fluid line having a restrictive orifice being connected to the fluid chamber and having means for connection to an inlet manifold of the internal combustion engine, whereby reduced pressure in the intake manifold serves to hold the valve element closed when the engine is running in excess of a predetermined speed.
Claim 8
Independent Claim
193 words
A device for decompressing an internal combustion engine during cranking and automatically progressively restoring compression thereto as the running speed of the engine increases, said device comprising a tubular housing threaded at one end for screwing to a port in the engine compression chamber, a valve seat located at the threaded end of the housing, a valve element having a stem which passes axially through the housing with said valve element protruding from the threaded end of the housing so as to close upon the valve seat with the passage of compressed gases from the engine compression chamber into said housing, venting means in the housing for the escape of compressed gases therein, a fluid chamber at the other end of the housing, a diaphragm on an end of the valve stem and defining one wall of the fluid chamber, and a fluid line having a restrictive orifice being connected to the fluid chamber and having means for connection to an inlet manifold of the internal combustion engine, whereby reduced pressure in the intake manifold serves to hold the valve element closed when the engine is running in excess of a predetermined speed.
Claim 9
Dependent Claim
28 words
A device according to claim 6, wherein the venting means is located between the diaphragm and the threaded end of the tubular housing, and comprises an air filter.
Claim 10
Dependent Claim
25 words
A device according to claim 6 including also a bias spring acting upon the valve stem to hold the valve element off the valve seat.
References Cited (Backward Citations)
US854035A
Cited
US3335711A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-12-05 | 1976-06-05 | 1976-12-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-12-05 | 1980-06-05 | 1980-12-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-12-05 | 1984-06-05 | 1984-12-05 | $7700.00 | Window Closed / Lapsed |