US4050433A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid fuel pumping apparatus
Assignee: ZF International UK Ltd
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Filing: 1975-12-15
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Granted: 1977-09-27
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Expires: 1995-12-15
Abstract
Abstract A fuel pump for supplying fuel to an internal combustion engine includes a cam ring movable angularly to determine the timing of injection of fuel. The cam ring is moved by a piston against the action of resilient means by fluid under pressure from the outlet of a feed pump the output pressure of which varies in accordance with the speed at which the apparatus is driven. A second piston is provided and this is moved by the aforesaid fluid pressure against the action of further resilient means in a direction away from the first mentioned piston. The second mentioned piston is subjected to a fluid pressure assisting the action of the further resilient means, the second fluid pressure depending upon the amount of fuel which is being supplied to the engine.
Inventors
- 👤 Kanenobu Tokashiki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:34
CPC Classifications
F; F02; F02M; F02M41/00; F02M41/08; F02M41/14; F02M41/1405; F02M41/1411; F02M41/1416
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
249 words
A liquid fuel pumping apparatus for supplying fuel to internal combustion engines, the apparatus comprising a first piston slidable within a cylinder, means coupling said first piston to a component of an injection pump whereby movement of said piston will alter the timing of delivery of fuel by the injection pump, first resilient means biasing said first piston towards one end of the cylinder, conduit means through which the pressure of fuel delivered by a feed pump can be applied to said first piston to move said first piston against the action of the resilient means and in a direction to advance the timing of delivery of fuel, a second piston housed within a further cylinder, second resilient means urging said second piston in the direction to engage said first piston to assist the action of fuel pressure acting on the first piston, said fuel pressure also acting on one side of said second piston to oppose the force exerted by the second resilient means, a further conduit through which a control pressure can be applied to the other side of said second piston and valve means operable in conjunction with throttle means for generating said control pressure, said valve means being arranged so that said control pressure is substantially equal to the output pressure of the feed pump when said throttle means is set to provide a low quantity of fuel and is substantially zero when the throttle means is set to provide a high quantity of fuel.
Claim 2
Dependent Claim
249 words
A liquid fuel pumping apparatus for supplying fuel to internal combustion engines, the apparatus comprising a first piston slidable within a cylinder, means coupling said first piston to a component of an injection pump whereby movement of said piston will alter the timing of delivery of fuel by the injection pump, first resilient means biasing said first piston towards one end of the cylinder, conduit means through which the pressure of fuel delivered by a feed pump can be applied to said first piston to move said first piston against the action of the resilient means and in a direction to advance the timing of delivery of fuel, a second piston housed within a further cylinder, second resilient means urging said second piston in the direction to engage said first piston to assist the action of fuel pressure acting on the first piston, said fuel pressure also acting on one side of said second piston to oppose the force exerted by the second resilient means, a further conduit through which a control pressure can be applied to the other side of said second piston and valve means operable in conjunction with throttle means for generating said control pressure, said valve means being arranged so that said control pressure is substantially equal to the output pressure of the feed pump when said throttle means is set to provide a low quantity of fuel and is substantially zero when the throttle means is set to provide a high quantity of fuel.
Claim 3
Dependent Claim
31 words
The apparatus as claimed in claim 1 in which said first resilient means exerts a higher force on said first piston than said second resilient means exerts on said second piston.
Claim 4
Dependent Claim
55 words
The apparatus as claimed in claim 1 in which said valve means is arranged so that the control pressure varies between substantially zero and the output pressure of the feed pump and the throttle means is moved between the positions in which a low and a high quantity of fuel is supplied by the apparatus.
Claim 5
Dependent Claim
30 words
The apparatus as claimed in claim 3 including non-return valves disposed in said conduits respectively, said non-return valves being positioned to permit fluid flow into the cylinders containing the pistons.
Claim 6
Dependent Claim
21 words
The apparatus as claimed in claim 4 in which the pistons and the walls of the respective cylinders define leakage paths.
Claim 7
Dependent Claim
25 words
The apparatus as claimed in claim 1 in which said valve means modifies the output pressure of the feed pump to provide said control pressure.
References Cited (Backward Citations)
US2916029A
Cited
US3943902A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-09-26 | 1981-03-28 | 1981-09-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-09-26 | 1985-03-28 | 1985-09-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-09-26 | 1989-03-28 | 1989-09-27 | $7700.00 | Window Closed / Lapsed |