US4940037A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fuel injection system for internal combustion engines
Assignee: Robert Bosch GmbH
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Filing: 1988-06-11
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Granted: 1990-07-10
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Expires: 2008-06-11
Abstract
Abstract A fuel injection system for an internal combustion engine and a method of controlling fuel injection according to which a predetermined fuel quantity is delivered from a high-pressure pump to the internal combustion engine, first and second return flow quantity are returned through first and second relief ducts, the second relief duct including a control throttle having a constant cross-section, and an electronic control unit controls flow delivery in accordance with characteristic values including those of the internal combustion engine, the pump, and a quantity measuring device for measuring the second return flow, and in accordance with the predetermined fuel delivery quantity also used as a characteristic value.
Inventors
- 👤 Konrad Eckert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:15
CPC Classifications
F; F02; F02M; F02M45/00; F02M59/00; F02M59/20; F02M59/36; F02M59/366; F02B; F02B2275/00; F02B2275/14; F02M2200/00; F02M2200/21; F02M2200/24; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
200 words
A fuel injection system for an internal combustion engine, said fuel injection system comprising: a high-pressure pump including pump work space and means for delivering a constant fuel quantity per a pump cycle from said pump work space; a first relief duct for returning a first return flow quantity; first open/close control means for controlling the first flow quantity flowing through said first relief duct to thereby determine a start and an end of the delivery; a second relief duct for returning a second return flow quantity and including a control throttle; and electronic control means for controlling the fuel delivery in accordance with characteristic values of the internal combustion engine and said high-pressure delivery pump; said control throttle having a constant cross-section, said fuel injection system further comprising quantity measuring means located in said second relief duct for measuring the second return flow quantity and a second open/close control means for controlling the second return flow quantity, said electronic control means comprising means for controlling the flow delivery in accordance with characteristic values of said quantity measuring means and said second open/close control means and in accordance with the constant fuel delivery quantity also used as a characteristic value.
Claim 2
Dependent Claim
200 words
A fuel injection system for an internal combustion engine, said fuel injection system comprising: a high-pressure pump including pump work space and means for delivering a constant fuel quantity per a pump cycle from said pump work space; a first relief duct for returning a first return flow quantity; first open/close control means for controlling the first flow quantity flowing through said first relief duct to thereby determine a start and an end of the delivery; a second relief duct for returning a second return flow quantity and including a control throttle; and electronic control means for controlling the fuel delivery in accordance with characteristic values of the internal combustion engine and said high-pressure delivery pump; said control throttle having a constant cross-section, said fuel injection system further comprising quantity measuring means located in said second relief duct for measuring the second return flow quantity and a second open/close control means for controlling the second return flow quantity, said electronic control means comprising means for controlling the flow delivery in accordance with characteristic values of said quantity measuring means and said second open/close control means and in accordance with the constant fuel delivery quantity also used as a characteristic value.
Claim 3
Dependent Claim
24 words
A fuel injection system according to claim 1 wherein said pressure measuring means and said second open/close control means each has electrical operating means.
Claim 4
Dependent Claim
44 words
A fuel injectioon system according to claim 2 wherein said second open/close control means is formed as a second valve comprising a second movable valve member, and also a second spring and second actuating means for controlling displacement of said second movable valve member.
Claim 5
Dependent Claim
44 words
A fuel injection system according to claim 3 wherein said first open/close control means is formed as a first valve comprising an first movable valve member, and also a first spring and first actuating means for controlling displacement of said first movable valve member.
Claim 6
Dependent Claim
41 words
A fuel injection system according to claim 4 wherein each of said first and second valves is formed as one of seat and spool vlaves, and each of said first and second actuating means comprises one of electromagnetic and piezoceramic means.
Claim 7
Dependent Claim
53 words
A fuel injection system according to claim 3 wherein said control throttle and said open/close control means are arranged one after the other, said fuel injection system comprising a vlave passage located upstream of said throttle and cooperating with said second valve member to form a throttling orifice for uncoupling said control throttle.
Claim 8
Dependent Claim
41 words
A fuel injection system according to claim 2 wherein said electronic control means is formed to compensate for fuel quantity flowing through said second open/close control means in accordance with lengthening of an injection period by said first open/close control means.
Claim 9
Dependent Claim
57 words
A fuel injection system according to claim 7 wherein said electronic control means comprising a module for determining a differential quantity which is equal to the predetermined delivery quantity minus a control quantity and for controlling a closing time and thereby an injection period of said first open/close control means in accordance with the determined differential quantity.
Claim 10
Dependent Claim
35 words
A fuel injection system according to claim 8 wherein said electronic control means is formed to control said first open/close control means in accordance with a fuel quantity flowing through said first open/close control means.
Claim 11
Dependent Claim
35 words
A fuel injection system according to claim 9 wherein said quantity measuring means is formed to measure the first return flow quantity, said first and second relief ducts merging upstream of said quantity measuring device.
Claim 12
Dependent Claim
59 words
A fuel injection system according to claim 2 wherein said quantity measuring means and said control throttle form a differential pressure sensor, said fuel injection system including movable means displaceable a distance corresponding to a pressure differential across said control throttle and a displacement quantity analog transmitter for measuring said distance and communicating it to said electronic control means.
Claim 13
Dependent Claim
15 words
A fuel injection system according to claim 11 wherein said movable means comprises a piston.
Claim 14
Dependent Claim
30 words
A fuel injection system according to claim 11 wherein said movable means comprises a diaphragm having an initial position and means for biasing said diaphragm to the initial position thereof.
Claim 15
Dependent Claim
17 words
A fuel injection system accoding to claim 13 wherein said control throttle is located in sqaid diaphragm.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-07-09 | 1994-01-08 | 1994-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-07-09 | 1998-01-08 | 1998-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-07-09 | 2002-01-08 | 2002-07-10 | $7700.00 | Window Closed / Lapsed |