Patent US3730150A successfully refreshed from Google Patents.
US3730150A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for control of valve operation
Assignee: Individual
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Filing: 1971-10-20
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Granted: 1973-05-01
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Expires: 1991-10-20
Abstract
Abstract An internal combustion engine with means to selectively control valve operation to achieve improved operating efficiency resulting in decreased exhaust pollution, added power and faster acceleration, easier start-up, and smoother idle. The amount of valve lift duration and overlap between the exhaust and intake valves is controlled in one embodiment by means of selectively axially shifting a camshaft formed with lobes contoured with ramp surfaces which vary in axial extent. Shifting of the cam carries the lobes into operating relationship with their associated valve operating means so that in one position a predetermined lobe ramp contour produces a relatively short overlap period for optimum engine operation at start-up, idling and low speed conditions, and at progressively axial spaced camshaft positions varied lobe ramp contours are moved into operating relationship with the cam followers to cause an increase in valve overlap for optimum operation at high speed engine conditions.
Inventors
- 👤 S Codner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:20
CPC Classifications
F; F02; F02D; F02D13/00; F02D13/02; F02D13/0203; F02D13/0215; F01; F01L; F01L13/00; F01L13/0015; F01L13/0036; F01L13/0042; F02D13/0261; F16; F16H; F16H25/00; F16H25/08; F16H25/10; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
398 words
Apparatus for use in an internal combustion engine having at least one combustion chamber with associated intake and exhaust valve means controlling the flow of intake charges and exhaust gasses into and from each chamber, including intake valve operating means to open said intake valve means for a predetermined lift duration period to induct a charge into said chamber for an intake phase, exhaust valve operating means to open said exhaust valve means for a predetermined lift duration period to scavenge exhaust gasses from the chamber for an exhaust phase, valve control means to cause a portion of the duration period of the said intake valve means to coincide with a portion of the duration period of said exhaust valve means for establishing an overlap period between termination of the exhaust phase and initiation of the intake phase, said valve control means including at least one camshaft driven in time relationship with said engine speed, said camshaft being formed with a plurality of intake and exhaust lobes, said lobes being formed into diametrically opposed ramp and heel portions, said ramp portions defining peripheral ramp surfaces which vary in axial extent between first ramp contours following a predetermined path for engine start-up and low engine speed operation and second ramp contours following a second predetermined path for high speed engine operation, said heel portion defining a peripheral surface of revolution generated by a line parallel with and moving in an arc about said camshaft, said intake valve operating means including cam follower means to follow said intake lobes between said first and second ramp contours thereof to operate said intake valve means, said exhaust valve operating means including cam follower means to follow said exhaust lobes between said first and second ramp contours thereof to operate said eXhaust valves, said cam follower means for said intake and exhaust valve operating means further including roller members mounted for rotation above respective axes generally parallel with said camshaft axis, said roller members being formed with a first substantially frusto conical peripheral surface conforming generally to the mating surface of said ramp portion of a respective lobe for rolling engagement therewith during opening of a respective valve, and the roller members being formed with a second substantially cylindrical peripheral surface mating with the surface of the heel portion of a respective lobe for rolling engagement therewith while the associated valve is closed.
Claim 2
Dependent Claim
398 words
Apparatus for use in an internal combustion engine having at least one combustion chamber with associated intake and exhaust valve means controlling the flow of intake charges and exhaust gasses into and from each chamber, including intake valve operating means to open said intake valve means for a predetermined lift duration period to induct a charge into said chamber for an intake phase, exhaust valve operating means to open said exhaust valve means for a predetermined lift duration period to scavenge exhaust gasses from the chamber for an exhaust phase, valve control means to cause a portion of the duration period of the said intake valve means to coincide with a portion of the duration period of said exhaust valve means for establishing an overlap period between termination of the exhaust phase and initiation of the intake phase, said valve control means including at least one camshaft driven in time relationship with said engine speed, said camshaft being formed with a plurality of intake and exhaust lobes, said lobes being formed into diametrically opposed ramp and heel portions, said ramp portions defining peripheral ramp surfaces which vary in axial extent between first ramp contours following a predetermined path for engine start-up and low engine speed operation and second ramp contours following a second predetermined path for high speed engine operation, said heel portion defining a peripheral surface of revolution generated by a line parallel with and moving in an arc about said camshaft, said intake valve operating means including cam follower means to follow said intake lobes between said first and second ramp contours thereof to operate said intake valve means, said exhaust valve operating means including cam follower means to follow said exhaust lobes between said first and second ramp contours thereof to operate said eXhaust valves, said cam follower means for said intake and exhaust valve operating means further including roller members mounted for rotation above respective axes generally parallel with said camshaft axis, said roller members being formed with a first substantially frusto conical peripheral surface conforming generally to the mating surface of said ramp portion of a respective lobe for rolling engagement therewith during opening of a respective valve, and the roller members being formed with a second substantially cylindrical peripheral surface mating with the surface of the heel portion of a respective lobe for rolling engagement therewith while the associated valve is closed.
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) | 1976-04-30 | 1976-10-30 | 1977-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-30 | 1980-10-30 | 1981-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-30 | 1984-10-30 | 1985-05-01 | $7700.00 | Window Closed / Lapsed |