US4383511A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control system
Assignee: ZF International UK Ltd
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Filing: 1981-02-04
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Granted: 1983-05-17
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Expires: 2001-02-04
Abstract
Abstract A control system for the fuel pump of an internal combustion engine includes a fuel determining network which controls the conduction of an output transistor by way of an input transistor. A transducer provides an operator demand signal to the network. In the event of failure of the network the transducer is arranged to control the supply of base circuit to the output transistor so that the conduction of the output transistor is directly controlled. The output transistor controls the flow of current in the winding of an actuator for the control member of the fuel pump.
Inventors
- 👤 Christopher Jones
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:52
CPC Classifications
F; F02; F02D; F02D41/00; F02D41/30; F02D41/3082; F02D41/22; F02D41/221; F02D41/38; F02D2041/224; F02D2041/226
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
206 words
A control system for the fuel pump of an internal combustion engine and of the kind comprising an electromagnetic actuator operable to determine the amount of fuel supplied by the pump, a control circuit including an output stage for controlling electric current flow in the actuator and a fuel determining network which controls the output stage, a demand transducer operable by the operator of the engine for supplying a demand signal to the fuel determining network, said output stage including an output transistor, a first resistor through which base current can be supplied to said output transistor to cause conduction thereof, current flow through said first resistor being cut off in the event that a failure or fault occurs in the fuel determining network, an input transistor the conduction of which is controlled by said fuel determining network, said input transistor acting to control the supply of base current to said output transistor, a potentiometer chain having a tapping connected to the base of said output transistor, said demand transducer forming a component of said potentiometer chain whereby when a failure of fault occurs in the fuel determining network, base current will be supplied to the output transistor under the direct control of the demand transducer.
Claim 2
Dependent Claim
206 words
A control system for the fuel pump of an internal combustion engine and of the kind comprising an electromagnetic actuator operable to determine the amount of fuel supplied by the pump, a control circuit including an output stage for controlling electric current flow in the actuator and a fuel determining network which controls the output stage, a demand transducer operable by the operator of the engine for supplying a demand signal to the fuel determining network, said output stage including an output transistor, a first resistor through which base current can be supplied to said output transistor to cause conduction thereof, current flow through said first resistor being cut off in the event that a failure or fault occurs in the fuel determining network, an input transistor the conduction of which is controlled by said fuel determining network, said input transistor acting to control the supply of base current to said output transistor, a potentiometer chain having a tapping connected to the base of said output transistor, said demand transducer forming a component of said potentiometer chain whereby when a failure of fault occurs in the fuel determining network, base current will be supplied to the output transistor under the direct control of the demand transducer.
Claim 3
Dependent Claim
21 words
A control system according to claim 1 in which said component comprises a potentiometer, the slider of which constitutes said tapping.
Claim 4
Dependent Claim
26 words
A control system according to claim 1 in which said component comprises a variable resistor, said tapping being from a fixed point in the potentiometer chain.
Claim 5
Dependent Claim
39 words
A control system according to claim 3 including a further variable resistor forming part of said demand transducer, said further variable resistor forming part of a further potentiometer chain, having a tapping at which is available said demand signal.
Claim 6
Dependent Claim
32 words
A control system according to claim 4 in which said variable resistors are defined by a potentiometer the slider of which is connected to one terminal of a source of electric supply.
Claim 7
Dependent Claim
46 words
A control system according to claim 2 or claim 3 including a diode connected between the tapping and the base of said output transistor, said diode being connected so as be reverse biased to prevent flow of current from said first resistor to the potentiometer chain.
Claim 8
Dependent Claim
42 words
A control system according to claim 6 in which said input transistor has its collector-emitter path connected to the base of said output transistor to divert the current flowing in said first resistor when the input transistor is in a conductive state.
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) | 1986-05-16 | 1986-11-15 | 1987-05-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-05-16 | 1990-11-15 | 1991-05-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-05-16 | 1994-11-15 | 1995-05-17 | $7700.00 | Window Closed / Lapsed |