US5499157A
Expired / Lapsed
US
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Multiplexed electronic fuel injection control system
Assignee: Woodward Inc
•
Filing: 1994-11-09
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Granted: 1996-03-12
•
Expires: 2014-11-09
Abstract
Abstract An electronic fuel injection control system having a plurality of fuel injection valves, wherein each valve is operated by an electromagnetic solenoid. The control system includes at least one driver circuit for supplying current limited power to the solenoid, at least one control circuit for controlling the current passing through the solenoid, and a multiplexing means for selectively interconnecting the at least one driver circuit and the at least one control circuit to the terminals of a selected solenoid for selectively energizing the solenoid. The multiplexing means includes two switch arrays. The first switch array has at least one switch that selectively interconnects at least one driver circuit to a first terminal of the solenoids. The second switch array has at least one switch selectively interconnecting at least one control circuit to a second terminal of the solenoids. The multiplexing means is further characterized in that the two switch arrays are interconnected among the at least one driver circuit, the at least one control circuit, and the solenoids so that closure of any single switch from each switch bank uniquely selects and energizes a single solenoid.
Inventors
- 👤 Ramin Younessi
- 👤 Dale A. Beckman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 08:06
CPC Classifications
F; F02; F02D; F02D41/00; F02D41/20; F02D41/30; F02D41/32; F02D41/36; H; H01; H01F; H01F7/00; H01F7/06; H01F7/08; H01F7/18; H01F7/1877; F02D2041/2003; F02D2041/2013; F02D2041/202; F02D2041/2024; F02D2041/2027; F02D2041/2031; F02D2041/2048; F02D2041/2058; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/40
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
173 words
An electronic fuel injection control system of the type having a plurality of fuel injection valves, each valve operated by an electromagnetic solenoid, the control system comprising: at least one driver circuit for supplying power to a selected solenoid; at least one control circuit for providing controlled operation of the selected solenoid; a multiplexing means for selectively interconnecting the at least one driver circuit and the at least one control circuit to the terminals of the selected solenoid for selectively energizing the selected solenoid, the means including: a first switch array having at least two switches selectively interconnecting at least one driver circuit to a first terminal of the solenoids; and a second switch array having at least two switches selectively interconnecting at least one control circuit to a second terminal of the solenoids; the multiplexing means being interconnected among the at least one driver circuit, the at least one control circuit, and the solenoids so that closure of any single switch from each switch array uniquely selects and energizes a single solenoid.
Claim 2
Dependent Claim
173 words
An electronic fuel injection control system of the type having a plurality of fuel injection valves, each valve operated by an electromagnetic solenoid, the control system comprising: at least one driver circuit for supplying power to a selected solenoid; at least one control circuit for providing controlled operation of the selected solenoid; a multiplexing means for selectively interconnecting the at least one driver circuit and the at least one control circuit to the terminals of the selected solenoid for selectively energizing the selected solenoid, the means including: a first switch array having at least two switches selectively interconnecting at least one driver circuit to a first terminal of the solenoids; and a second switch array having at least two switches selectively interconnecting at least one control circuit to a second terminal of the solenoids; the multiplexing means being interconnected among the at least one driver circuit, the at least one control circuit, and the solenoids so that closure of any single switch from each switch array uniquely selects and energizes a single solenoid.
Claim 3
Dependent Claim
46 words
The control system according to claim 1, wherein the multiplexing means is interconnected among the at least one driver circuit, the at least one control circuit, and the solenoids, in such a way that the number of control circuits is less than the number of solenoids.
Claim 4
Dependent Claim
46 words
The control system according to claim 1, wherein the multiplexing means is interconnected among the at least one driver circuit, the at least one control circuit, and the solenoids, in such a way that the number of driver circuits is less than the number of solenoids.
Claim 5
Dependent Claim
30 words
The control system according to claim 1, wherein the product of the number of driver circuits multiplied by the number of control circuits is equal to the number of solenoids.
Claim 6
Dependent Claim
19 words
The control system according to claim 4, wherein the switches of the driver and control circuits are transistor switches.
Claim 7
Dependent Claim
44 words
The control system according to claim 1, wherein the product of the number of driver circuits multiplied by the number of control circuits is equal to the product of the number of solenoids multiplied by the number of solenoids that may be energized simultaneously.
Claim 8
Dependent Claim
27 words
The control system according to claim 1, further including blocking diodes in series connection with the solenoids, the blocking diodes prohibiting reverse current flow through the solenoids.
Claim 9
Dependent Claim
154 words
An electronic fuel injection control system of the type having a plurality of fuel injection valves, each valve operated by an electromagnetic solenoid, the control system comprising: at least one driver circuit for supplying power to a drive terminal of the solenoids, the driver circuit including a current limiting circuit for safeguarding the system from excessive current surges; at least one control circuit for controlling the current flow through a selected solenoid; a first array of switches electrically connected in series between the power source and the first terminals of the solenoids; and a second array of switches electrically connected in series between the control circuits and a second terminal on the solenoids; the first and second arrays of switches being interconnected among the power source, the at least one control circuit, and the solenoids so that closure of any single switch from each array of switches uniquely selects and energizes a single solenoid.
Claim 10
Dependent Claim
154 words
An electronic fuel injection control system of the type having a plurality of fuel injection valves, each valve operated by an electromagnetic solenoid, the control system comprising: at least one driver circuit for supplying power to a drive terminal of the solenoids, the driver circuit including a current limiting circuit for safeguarding the system from excessive current surges; at least one control circuit for controlling the current flow through a selected solenoid; a first array of switches electrically connected in series between the power source and the first terminals of the solenoids; and a second array of switches electrically connected in series between the control circuits and a second terminal on the solenoids; the first and second arrays of switches being interconnected among the power source, the at least one control circuit, and the solenoids so that closure of any single switch from each array of switches uniquely selects and energizes a single solenoid.
Claim 11
Dependent Claim
44 words
The control system according to claim 8, wherein the arrays of switches are interconnected among the power source, the at least one control circuit, and the solenoids, in such a way that the number of control circuits is less than the number of solenoids.
Claim 12
Dependent Claim
21 words
The control system according to claim 9, wherein the switches of the first and second arrays of switches are transistor switches.
Claim 13
Dependent Claim
206 words
An electronic fuel injection control system of the type having a plurality of fuel injection valves, each valve operated by an electromagnetic solenoid, the control system comprising: at least one driver circuit for supplying power to a drive terminal of the solenoids, the driver circuit including means for providing continuous current flow through a selected solenoid throughout the fuel injection cycle; at least one control circuit for controlling the current flow through the selected solenoid, the control circuit being configured to operate by pulse width modulating the voltage applied across the selected solenoid to effect a predetermined current flow therethrough; a first array of transistor switches electrically connected in series between the at least one driver circuit and the drive terminals of the solenoids; a second array of switches electrically connected in series between the control circuits and control terminals of the solenoids; the first and second arrays of switches being interconnected among the at least one driver circuit, the at least one control circuit, and the solenoids so that closure of any single switch from each array of switches uniquely selects and energizes a single solenoid; and a central computer having output signals for selectively operating the individual transistor switches of each array of switches.
Claim 14
Dependent Claim
206 words
An electronic fuel injection control system of the type having a plurality of fuel injection valves, each valve operated by an electromagnetic solenoid, the control system comprising: at least one driver circuit for supplying power to a drive terminal of the solenoids, the driver circuit including means for providing continuous current flow through a selected solenoid throughout the fuel injection cycle; at least one control circuit for controlling the current flow through the selected solenoid, the control circuit being configured to operate by pulse width modulating the voltage applied across the selected solenoid to effect a predetermined current flow therethrough; a first array of transistor switches electrically connected in series between the at least one driver circuit and the drive terminals of the solenoids; a second array of switches electrically connected in series between the control circuits and control terminals of the solenoids; the first and second arrays of switches being interconnected among the at least one driver circuit, the at least one control circuit, and the solenoids so that closure of any single switch from each array of switches uniquely selects and energizes a single solenoid; and a central computer having output signals for selectively operating the individual transistor switches of each array of switches.
Claim 15
Dependent Claim
177 words
An electronic fuel injection control system of the type having a plurality of fuel injection valves, each valve operated by an electromagnetic solenoid, the control system comprising: at least one driver circuit for supplying power to the solenoid during a fuel injection cycle, the driver circuit including means for collapsing the magnetic field of a selected solenoid and, thus, rapidly dissipating the energy stored therein at the end of the fuel injection cycle; at least one control circuit for providing precision control of the current flow through the selected solenoid during the fuel injection cycle; a first array of switches electrically connected in series between the power source and the first terminals of the solenoids; and a second array of switches electrically connected in series between the control circuits and a second terminal on the solenoids; the first and second arrays of switches being interconnected among the power source, the at least one control circuit, and the solenoids so that closure of any single switch from each array of switches uniquely selects and energizes a single solenoid.
Claim 16
Dependent Claim
177 words
An electronic fuel injection control system of the type having a plurality of fuel injection valves, each valve operated by an electromagnetic solenoid, the control system comprising: at least one driver circuit for supplying power to the solenoid during a fuel injection cycle, the driver circuit including means for collapsing the magnetic field of a selected solenoid and, thus, rapidly dissipating the energy stored therein at the end of the fuel injection cycle; at least one control circuit for providing precision control of the current flow through the selected solenoid during the fuel injection cycle; a first array of switches electrically connected in series between the power source and the first terminals of the solenoids; and a second array of switches electrically connected in series between the control circuits and a second terminal on the solenoids; the first and second arrays of switches being interconnected among the power source, the at least one control circuit, and the solenoids so that closure of any single switch from each array of switches uniquely selects and energizes a single solenoid.
Claim 17
Dependent Claim
35 words
The electronic fuel injection control system according to claim 12, wherein the at least one driver circuit further includes a means for maintaining continuous current flow through the selected solenoid throughout the fuel injection cycle.
Claim 18
Dependent Claim
26 words
The electronic fuel injection control system according to claim 13, wherein the means for maintaining continuous current flow includes a flyback diode and a driver switch.
Claim 19
Dependent Claim
44 words
The electronic fuel injection control system according to claim 14, wherein a closed current loop for maintaining current flow through the selected solenoid is formed by the flyback diode, the solenoid, and the driver switch, when the driver switch is in the closed position.
Claim 20
Dependent Claim
29 words
The electronic fuel injection control system according to claim 12, wherein the means for collapsing the magnetic field includes a speedup diode, a flyback diode, and a driver switch.
Claim 21
Dependent Claim
48 words
The electronic fuel injection control system according to claim 16, wherein a closed current loop for dissipating the energy stored in the selected solenoid is formed by the speedup diode, the solenoid, the flyback diode, and a power supply, when the driver switch is in the open position.
Claim 22
Dependent Claim
30 words
The electronic fuel injection control system according to claim 12, further including blocking diodes in series connection with the solenoids, the blocking diodes prohibiting reverse current flow through the solenoids.
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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) | 1999-03-12 | 1999-09-11 | 2000-03-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-03-12 | 2003-09-11 | 2004-03-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-03-12 | 2007-09-11 | 2008-03-12 | $7700.00 | Window Closed / Lapsed |