US3995607A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vacuum retard delay valve
Assignee: Siemens Bendix Automotive Electronics Ltd
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Filing: 1975-04-14
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Granted: 1976-12-07
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Expires: 1995-04-14
Abstract
Abstract An internal combustion engine for automotive vehicles is started and operated with decreased fuel enrichment when the engine is cold by delaying spark retard as the vehicle is accelerated to save fuel and reduce accumulated pollutants collected during warm up. A valve is provided between the carburetor spark port and the distributor vacuum advance cylinder to permit unrestricted airflow from the vacuum advance cylinder to the spark port at all temperatures and to restrict airflow from the spark port to the vacuum advance cylinder when the engine operating temperature is below a predetermined temperature. When the engine operating temperature attains the predetermined temperature airflow is unrestricted in both directions and the vacuum advance operates in a normal manner.
Inventors
- 👤 George Ludwig
- 👤 William J. Walters
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 09:11
CPC Classifications
F; F02; F02P; F02P5/00; F02P5/04; F02P5/05; F02P5/10; F02P5/103; Y; Y10; Y10T; Y10T137/00; Y10T137/7722; Y10T137/7737; Y10T137/7837; Y10T137/7847
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
73 words
A method of operating an internal combustion engine with decreased fuel enrichment when the engine is cold, the engine having a vacuum controlled spark advance connected to a vacuum source, including the steps of advancing the spark in the normal manner upon starting the engine when cold, delaying spark retard upon accelerating the engine when cold to prevent engine stall, and retarding the spark in the normal manner after the engine warms up.
Claim 2
Independent Claim
73 words
A method of operating an internal combustion engine with decreased fuel enrichment when the engine is cold, the engine having a vacuum controlled spark advance connected to a vacuum source, including the steps of advancing the spark in the normal manner upon starting the engine when cold, delaying spark retard upon accelerating the engine when cold to prevent engine stall, and retarding the spark in the normal manner after the engine warms up.
Claim 3
Dependent Claim
36 words
A method of operating an internal combustion engine as described in claim 1 including the step of effectively slowly bleeding the vacuum in the spark advance to delay spark retard upon accelerating the engine when cold.
Claim 4
Dependent Claim
28 words
A method of operating an internal combustion engine as described in claim 2 including the step of effectively advancing the spark at all operating temperatures after spark retard.
Claim 5
Dependent Claim
35 words
A method of operating an internal combustion engine as described in claim 2 including the step of effectively by-passing the slow bleed to retard the spark upon accelerating the engine after the engine warms up.
Claim 6
Dependent Claim
31 words
A method of operating an internal combustion engine as described in claim 4 including the step of effectively retarding the spark upon accelerating the engine above a predetermined engine operating temperature.
Claim 7
Dependent Claim
114 words
In an internal combustion engine having a vacuum controlled spark advance connected to a vacuum source to advance the spark upon starting the engine when cold, the improvement comprising valve means between the spark advance and vacuum source having means for permitting substantially unrestricted flow in one direction from the spark advance to the vacuum source to advance the spark, means for restricting flow in the opposite direction from the vacuum source to the spark advance to delay spark retard upon accelerating the engine when cold, and means for providing substantially unrestricted flow from the vacuum source to the spark advance when the engine warms up to advance the spark in the normal manner.
Claim 8
Dependent Claim
114 words
In an internal combustion engine having a vacuum controlled spark advance connected to a vacuum source to advance the spark upon starting the engine when cold, the improvement comprising valve means between the spark advance and vacuum source having means for permitting substantially unrestricted flow in one direction from the spark advance to the vacuum source to advance the spark, means for restricting flow in the opposite direction from the vacuum source to the spark advance to delay spark retard upon accelerating the engine when cold, and means for providing substantially unrestricted flow from the vacuum source to the spark advance when the engine warms up to advance the spark in the normal manner.
Claim 9
Dependent Claim
54 words
In an internal combustion engine as described in claim 6 in which the means for providing substantially unrestricted flow from the vacuum source to the spark advance when the engine warms up includes a bimetal element responsive to changes in temperature, and a valve operated by the bimetal element at a predetermined engine temperature.
Claim 10
Dependent Claim
21 words
In an internal combustion engine as described in claim 6 in which the means for restricting flow includes a restricted orifice.
Claim 11
Dependent Claim
20 words
In an internal combustion engine as described in claim 8 in which the orifice is calibrated to meter flow therethrough.
Claim 12
Dependent Claim
43 words
In an internal combustion engine as described in claim 8 in which the means for providing substantially unrestricted flow from the vacuum source to the spark advance when the engine warms up includes means responsive to engine temperature for by-passing the restricted orifice.
Claim 13
Independent Claim
88 words
A method of operating an internal combustion engine with decreased fuel enrichment when the engine is cold, the engine having a vacuum controlled spark advance connected to a vacuum source, including the steps of permitting comparatively uninhibited communication between the vacuum source and the spark advance upon starting the engine when cold, restricting communication therebetween upon accelerating the engine when cold to prevent engine stall, and again permitting comparatively uninhibited communication between the vacuum source and the spark advance upon accelerating the engine after the engine warms up.
Claim 14
Independent Claim
88 words
A method of operating an internal combustion engine with decreased fuel enrichment when the engine is cold, the engine having a vacuum controlled spark advance connected to a vacuum source, including the steps of permitting comparatively uninhibited communication between the vacuum source and the spark advance upon starting the engine when cold, restricting communication therebetween upon accelerating the engine when cold to prevent engine stall, and again permitting comparatively uninhibited communication between the vacuum source and the spark advance upon accelerating the engine after the engine warms up.
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) | 1979-12-07 | 1980-06-07 | 1980-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-12-07 | 1984-06-07 | 1984-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-12-07 | 1988-06-07 | 1988-12-07 | $7700.00 | Window Closed / Lapsed |