US3705572A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fuel injection systems for internal combustion engines
Assignee: AE PLC
•
Filing: 1970-11-10
•
Granted: 1972-12-12
•
Expires: 1990-11-10
Abstract
Abstract Fuel from a fuel pressure source is injected by fuel injection valves into the induction passage of an engine and means are provided to vary the pressure of the fuel pressure source in accordance with the engine induction passage pressure, in the sense of reducing the fuel pressure when the induction passage pressure is reduced and vice versa.
Inventors
- 👤 George Vincent Bloomfield
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:49
CPC Classifications
F; F02; F02M; F02M51/00; F02M51/02; F02D; F02D17/00; F02D17/04; F02D41/00; F02D41/008; F02D41/0087
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
207 words
In a fuel injection system for an internal combustion engine wherein fuel is fed to the engine through one or more electrically-operated fuel injection valves, and including a pulse generator which produces pulses of a duration depending on one or more parameters of engine operation for intermittently energizing the valve or valves to open to pass fuel, means for triggering the pulse generator in timed relation to the engine operating cycle, means for feeding one or more control signals varying as a function of a parameter of engine operation, including a control signal dependent on induction passage pressure, to the pulse generator in order to control the duration of the energizing pulses fed to open the injection valve or valves, and wherein the fuel is injected by the or each valve into an induction passage of the engine and the or each valve is supplied from a fuel pressure source, the improvement which consists in maintaining a substantially constant fuel pressure difference across the fuel injection valve or valves by providing means to vary the pressure of the fuel pressure source in accordance with the engine induction passage pressure, in the sense of reducing the fuel pressure when the induction passage pressure is reduced and vice versa.
Claim 2
Dependent Claim
207 words
In a fuel injection system for an internal combustion engine wherein fuel is fed to the engine through one or more electrically-operated fuel injection valves, and including a pulse generator which produces pulses of a duration depending on one or more parameters of engine operation for intermittently energizing the valve or valves to open to pass fuel, means for triggering the pulse generator in timed relation to the engine operating cycle, means for feeding one or more control signals varying as a function of a parameter of engine operation, including a control signal dependent on induction passage pressure, to the pulse generator in order to control the duration of the energizing pulses fed to open the injection valve or valves, and wherein the fuel is injected by the or each valve into an induction passage of the engine and the or each valve is supplied from a fuel pressure source, the improvement which consists in maintaining a substantially constant fuel pressure difference across the fuel injection valve or valves by providing means to vary the pressure of the fuel pressure source in accordance with the engine induction passage pressure, in the sense of reducing the fuel pressure when the induction passage pressure is reduced and vice versa.
Claim 3
Dependent Claim
83 words
A system as claimed in claim 1, in which the fuel is fed from a fuel tank to a fuel supply line cOnnected to each injection valve and a return line is connected from each injection valve, by means of which excess fuel can be returned to the fuel tank, wherein a pressure-operated valve is connected between the fuel supply line and the fuel return line, said valve being controlled in accordance with the pressure existing in the induction passage of the engine.
Claim 4
Dependent Claim
28 words
A system as claimed in claim 2, including a connection from the induction passage downstream of the throttle valve of the engine and leading to said pressure-operated valve.
Claim 5
Dependent Claim
44 words
A system as claimed in claim 3, in which the pressure-operated valve comprises a diaphragm having one side exposed to induction passage pressure, and the arrangement is such that an increase in the induction passage pressure tends to close the valve, and vice versa.
Claim 6
Dependent Claim
25 words
A system as claimed in claim 4, in which the other side of the diaphragm is subjected to the pressure in the fuel return line.
Claim 7
Dependent Claim
102 words
A system as claimed in claim 5, comprising a valve body, a splined valve member arranged within the valve body and having a shoulder which cooperates with a shoulder on the valve body to form a fuel metering throat, a spring acting on said valve body, a diaphragm extending between the valve member and the valve body, a connection from the fuel return line to the valve body at the other side of the diaphragm and one end of the valve member, and a connection from the fuel supply line to the valve body at the other end of the valve member.
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) | 1975-12-12 | 1976-06-12 | 1976-12-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-12-12 | 1980-06-12 | 1980-12-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-12-12 | 1984-06-12 | 1984-12-12 | $7700.00 | Window Closed / Lapsed |