US4168940A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fuel injection pump
Assignee: Robert Bosch GmbH
•
Filing: 1977-10-05
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Granted: 1979-09-25
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Expires: 1997-10-05
Abstract
Abstract A fuel injection pump for delivery of fuel under high pressure to combustion chambers and in which the fuel is delivered by a rotating and reciprocating pump piston. The relative angular position of the pump piston with respect to its drive shaft defines the timing of fuel injection. This timing is varied in accordance with engine speed by a hydraulic servo-mechanism which includes a piston moving against two springs, one of which comes into engagement before the other so that the change of injection timing as a function of engine speed follows two different curves.
Inventors
- 👤 Karl Konrath
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:03
CPC Classifications
F; F02; F02M; F02M41/00; F02M41/08; F02M41/10; F02M41/12; F02M41/123; F02M41/128
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
161 words
A fuel injection pump which includes a housing defining a cylindrical bore containing and guiding a pump piston connected to means for causing the simultaneous rotation and reciprocation of said pump piston, and which further includes adjusting means for causing reciprocation of said piston, said adjusting means being subject to fluid pressure, said fluid pressure being a function of engine speed, and wherein the improvement comprises: said adjusting means includes: a cylinder and an adjusting piston guided within said cylinder; a first spring disposed in said cylinder so as to oppose the movement of said adjusting piston in one direction of motion thereof; a second spring, disposed in said cylinder so as to come into engagement with said piston at a different point in said cylinder from said first spring and after said piston has moved a given distance against the force of said first spring; and a pin mounted in said housing to provide axial support for said second spring.
Claim 2
Dependent Claim
161 words
A fuel injection pump which includes a housing defining a cylindrical bore containing and guiding a pump piston connected to means for causing the simultaneous rotation and reciprocation of said pump piston, and which further includes adjusting means for causing reciprocation of said piston, said adjusting means being subject to fluid pressure, said fluid pressure being a function of engine speed, and wherein the improvement comprises: said adjusting means includes: a cylinder and an adjusting piston guided within said cylinder; a first spring disposed in said cylinder so as to oppose the movement of said adjusting piston in one direction of motion thereof; a second spring, disposed in said cylinder so as to come into engagement with said piston at a different point in said cylinder from said first spring and after said piston has moved a given distance against the force of said first spring; and a pin mounted in said housing to provide axial support for said second spring.
Claim 3
Dependent Claim
16 words
A fuel injection pump as defined by claim 1, including means for changing said given distance.
Claim 4
Dependent Claim
20 words
A fuel injection pump as defined by claim 1, wherein said pin is press-fit in a hole in said housing.
Claim 5
Dependent Claim
47 words
A fuel injection pump as defined by claim 1, further comprising a sleeve guided coaxially by said pin and moving externally thereof, said sleeve being interposed between said adjusting piston and said second spring and serving to transmit forces between said adjusting piston and said second spring.
Claim 6
Dependent Claim
20 words
A fuel injection pump as defined by claim 4, wherein said pin is press-fit in a hole in said housing.
References Cited (Backward Citations)
FR889272A
Cited
US3635603A
Cited
US4036193A
Cited
US3906916A
Cited
US3910724A
Cited
US3945360A
Cited
US3942914A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-09-24 | 1983-03-26 | 1983-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-09-24 | 1987-03-26 | 1987-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-09-24 | 1991-03-26 | 1991-09-25 | $7700.00 | Window Closed / Lapsed |