US3738576A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Injection nozzle for direct injection engine
Assignee: Physics International Co
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Filing: 1971-04-21
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Granted: 1973-06-12
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Expires: 1991-04-21
Abstract
Abstract An improved needle valve spring apparatus for a fuel injection assembly of the type wherein pressured fuel from a supply conduit is pumped at each cycle to a needle valve which opens to allow the pumped fuel to enter the combustion cylinder. The spring chamber that supplies spring force to the needle valve member to normally keep it closed, and that heretofore contained only a coil spring, is filled with pressured fuel that acts as a spring. The spring chamber is sealed against the outflow of fuel therefrom, and a passage with a check valve therein connects the pressurized fuel supply line to the spring chamber to fill the spring chamber with pressurized fuel when the engine is started.
Inventors
- 👤 C O'neill
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 11:31
CPC Classifications
F; F02; F02M; F02M61/00; F02M61/16; F02M61/20; F02M61/205; F02M47/00; F02M47/06; F02M51/00; F02M51/04; F02M57/00; F02M57/02; F02M57/022; F02M57/027; F02B; F02B2275/00; F02B2275/14; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
195 words
In an internal combustion engine which includes a pressurized fuel supply conduit, an injection nozzle region, an injection pump coupled to the conduit and nozzle region to provide fuel pulses at the nozzle region, and an injection valve member for sliding within a valve housing in a direction to open the nozzle region to the outflow of fuel therefrom when a predetermined high pressure is exceeded at the nozzle region, the improvement comprising: means defining a fluid chamber which is coupled to said valve member to supply spring forces to said valve member that resist sliding of said valve member in a direction to open said nozzle region, said fluid chamber substantially sealed against the outflow of fluid therefrom so that rapid movement of said valve member in a direction to open the nozzle region compresses fluid in said chamber; and said fluid chamber being coupled to said nozzle region by clearance between the valve member and the housing portion in which it slides, so that fuel can leak from said nozzle region to said fluid chamber to maintain a fuel pressure in said chamber approximately equal to the average pressure at said nozzle region.
Claim 2
Dependent Claim
195 words
In an internal combustion engine which includes a pressurized fuel supply conduit, an injection nozzle region, an injection pump coupled to the conduit and nozzle region to provide fuel pulses at the nozzle region, and an injection valve member for sliding within a valve housing in a direction to open the nozzle region to the outflow of fuel therefrom when a predetermined high pressure is exceeded at the nozzle region, the improvement comprising: means defining a fluid chamber which is coupled to said valve member to supply spring forces to said valve member that resist sliding of said valve member in a direction to open said nozzle region, said fluid chamber substantially sealed against the outflow of fluid therefrom so that rapid movement of said valve member in a direction to open the nozzle region compresses fluid in said chamber; and said fluid chamber being coupled to said nozzle region by clearance between the valve member and the housing portion in which it slides, so that fuel can leak from said nozzle region to said fluid chamber to maintain a fuel pressure in said chamber approximately equal to the average pressure at said nozzle region.
Claim 3
Dependent Claim
58 words
The improvement described in claim 1 including: means defining a passage which couples said pressurized fuel supply conduit to said fluid chamber; and check valve means positioned along said passage to permit the flow of fuel only in a direction from said conduit to said chamber, whereby to fill said chamber when said engine is prepared for starting.
Claim 4
Dependent Claim
27 words
The improvement described in claim 1 including: an auxiliary spring located in said fluid chamber and preloaded to urge said valve member to close said nozzle region.
Claim 5
Dependent Claim
149 words
In an internal combustion engine which includes a fuel supply conduit for carrying fuel under a pressure of at least several atmospheres, a check valve connecting the fuel supply conduit to an injection pump, and a channel for carrying fuel from the injection pump to the nozzle region of an injection valve, the injection valve having a spring chamber that can supply forces which urge a valve member to close the nozzle but the valve member being moveable to open the nozzle to permit outflow of fuel when there is a predetermined high fuel pressure at the nozzle region, the improvement comprising: check valve means coupling said spring chamber to said pressurized fuel supply conduit for permitting the flow of fuel from said fuel supply conduit to said spring chamber but not in the opposite direction; and said spring chamber being substantially sealed against the outflow of fuel therefrom.
Claim 6
Dependent Claim
149 words
In an internal combustion engine which includes a fuel supply conduit for carrying fuel under a pressure of at least several atmospheres, a check valve connecting the fuel supply conduit to an injection pump, and a channel for carrying fuel from the injection pump to the nozzle region of an injection valve, the injection valve having a spring chamber that can supply forces which urge a valve member to close the nozzle but the valve member being moveable to open the nozzle to permit outflow of fuel when there is a predetermined high fuel pressure at the nozzle region, the improvement comprising: check valve means coupling said spring chamber to said pressurized fuel supply conduit for permitting the flow of fuel from said fuel supply conduit to said spring chamber but not in the opposite direction; and said spring chamber being substantially sealed against the outflow of fuel therefrom.
Claim 7
Dependent Claim
44 words
The improvement described in claim 4 including: a coil spring disposed in said spring chamber to urge said valve member to close said nozzle, said coil spring preloaded to a force less than one-half the total closing force normally required to prevent nozzle opening.
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) | 1976-06-11 | 1976-12-11 | 1977-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-11 | 1980-12-11 | 1981-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-11 | 1984-12-11 | 1985-06-12 | $7700.00 | Window Closed / Lapsed |