US3687121A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fuel system
Assignee: Borg Warner Corp
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Filing: 1970-12-28
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Granted: 1972-08-29
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Expires: 1990-12-28
Abstract
Abstract A fuel system for an internal combustion engine employs fluid logic devices for controlling a fuel injector valve. The fuel requirement is delivered in intermittent pulses having variable time duration as necessary to meet changes in the fuel requirement. Fluid logic devices provide a control signal for operating the fuel injector valve in the form of a train of pulses having a repetition rate N and pulse width of Q/N where N is a function of engine speed and Q is a function of the flow rate of air inducted into the engine. Thus the train of pulses provides a control signal related to N X (Q/N) Q which is desirable for maintaining a selected air-fuel ratio. The logic circuitry includes a variable pulse width multivibrator having an external bias connection providing an output signal in the form of a train of pulses having a repetition rate corresponding to a first input signal and a pulse width related to the reciprocal of the bias signal pressure.
Inventors
- 👤 John J Tuzson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:37
CPC Classifications
F; F15; F15C; F15C1/00; F15C1/002; Y; Y10; Y10S; Y10S123/00; Y10S123/10; Y10S261/00; Y10S261/69
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
222 words
A fuel system for an internal combustion engine including a source of fuel under pressure, a fuel valve connected to said fuel source arranged for admitting intermittent timed injections of fuel to said engine in response to a periodic pneumatic control signal, and control means connected to said fuel valve for providing said periodic pneumatic control signal comprising: a source of pneumatic signal energy; reference signal means connected to said engine providing a train of pneumatic triggering pulses having a repetition rate related to engine speed; bias signal means connected to said engine providing a pneumatic pressure signal related to a selected operating condition thereof; and pneumatic control signal forming apparatus including a primary fluidic gate device having a power nozzle connected to said signal energy source, a first preferred receiver leg, a second alternate receiver leg connected to said fuel valve, a control port connected to said reference signal means, and an inhibitor port connected to said reference signal means through a fluid capacitance coupling providing a multivibrator configuration, said inhibitor port being connected to said bias signal means, said gate device providing said pneumatic control signal in said second receiver leg in the form of a train of intermittent pressure pulses having a time duration inversely related to said bias signal pressure and a repetition rate related to engine speed.
Claim 2
Dependent Claim
222 words
A fuel system for an internal combustion engine including a source of fuel under pressure, a fuel valve connected to said fuel source arranged for admitting intermittent timed injections of fuel to said engine in response to a periodic pneumatic control signal, and control means connected to said fuel valve for providing said periodic pneumatic control signal comprising: a source of pneumatic signal energy; reference signal means connected to said engine providing a train of pneumatic triggering pulses having a repetition rate related to engine speed; bias signal means connected to said engine providing a pneumatic pressure signal related to a selected operating condition thereof; and pneumatic control signal forming apparatus including a primary fluidic gate device having a power nozzle connected to said signal energy source, a first preferred receiver leg, a second alternate receiver leg connected to said fuel valve, a control port connected to said reference signal means, and an inhibitor port connected to said reference signal means through a fluid capacitance coupling providing a multivibrator configuration, said inhibitor port being connected to said bias signal means, said gate device providing said pneumatic control signal in said second receiver leg in the form of a train of intermittent pressure pulses having a time duration inversely related to said bias signal pressure and a repetition rate related to engine speed.
Claim 3
Dependent Claim
111 words
A fuel system according to claim 1 in which said bias signal means is connected to said engine for monitoring engine speed and the flow rate of inducted air, said bias signal means providing a bias pressure which is the analogue of N/Q where N equals engine revolutions per unit of time and Q equals volume of inducted air per unit of time, said primary gate device providing said pneumatic control signal in the form of a train of pressure pulses having the relationship N X Q/N, such that the quantity of fuel delivered in a finite time period is proportional to the quantity of air inducted in said time period.
Claim 4
Dependent Claim
216 words
A fuel system according to claim 1 in which said bias signal means includes a fluid capacitance filter, a second fluidic gate device and flow rate measuring means connected in an inlet passage of said engine providing a pneumatic pressure analogue of Q where Q represents the volume of air inducted into said engine per unit of time, said second fluidic gate device having a preferred receiver leg and an alternate receiver leg connected to said filter, a control port and an inhibitor port connected to said reference signal means in a multivibrator configuration, said inhibitor port being connected to said flow rate measuring means for receiving said analogue of Q pressure signal, said second gate device providing a train of pressure pulses in said alternate receiver having a time duration proportional to 1/Q and a repetition rate N where N represents engine revolutions per unit of time, said fluid capacitance filter integrating said train of pulses providing a bias pressure signal corresponding to the analogue of N/Q, said primary gate device providing said pneumatic control signal in the form of a train of pressure pulses having the relationship N X Q/N, such that the quantity of fuel delivered in a finite time period is proportional to the quantity of air inducted in said time period.
Claim 5
Dependent Claim
118 words
A fuel system according to claim 3 in which said flow rate measuring means includes a proportional amplifier and a venturi arranged for measuring the flow rate of air inducted into said engine, said proportional amplifier having receiver means connected to said inhibitor port of said second fluidic gate device and having control port means connected to the throat of said venturi, said proportional amplifier being biased for operation near saturation providing a positive going output pressure change in said receiver means in response to a negative going pressure change in said control port means, said pressure change in said receiver means being approximately proportional to the square root of said pressure change in said control port means.
Claim 6
Dependent Claim
106 words
A fuel system according to claim 3 in which said flow rate measuring means includes a venturi arranged for measuring the flow rate of air inducted into said engine, a sharp edged orifice and a laminar restriction connected in series between atmosphere and the throat of said venturi, and a proportional amplifier biased for linear response, said proportional amplifier having receiver means connected to said inhibitor port of said second fluidic gate device, and having control port means connected across said laminar restriction, said proportional amplifier providing pressure changes in said receiver means proportional to changes in the flow rate of air inducted into said engine.
References Cited (Backward Citations)
US3556063A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-29 | 1976-02-28 | 1976-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-29 | 1980-02-28 | 1980-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-29 | 1984-02-28 | 1984-08-29 | $7700.00 | Window Closed / Lapsed |