Patent US3881128A successfully refreshed from Google Patents.
US3881128A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical load control for a motor vehicle
Assignee: Individual
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Filing: 1974-02-20
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Granted: 1975-04-29
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Expires: 1994-02-20
Abstract
Abstract A power control for an electrical load, such as exterior lighting, in a motor vehicle. Electrical power is provided to the load circuit through the contacts of a relay which is activated when the motor vehicle ignition is on. When the ignition is off, and the load circuit is coupled to the relay contacts, the relay is activated through an alternative circuit path which includes two transistor switches in series. A timing circuit is operable to turn off one of these transistors when a predetermined time has elapsed after the activation of the relay.
Inventors
- 👤 Carl L Douglas
- 👤 Timothy Smith
- 👤 Richard W Crenshaw
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 14:07
CPC Classifications
B; B60; B60Q; B60Q9/00; B60Q9/001
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
230 words
A power control for an electrical load in a motor vehicle comprising: a motor vehicle electrical load circuit; control means, having a control input, a load input and an output, the load input being coupled to a source of electrical power, for coupling its output to its load input when its control input is coupled to a source of electrical power; a first switch operable in a first position to couple the control input of the control means to a source of electrical power and in a second position to decouple the control input of the control means from a source of electrical power; a second switch operable in a first position to couple the output of the control means to the load circuit and in a second position to decouple the output of the control means from the load circuit; first circuit means, responsive to the positioning of the sEcond switch and coupled from the second switch, for coupling a source electrical power to the control input of the control means in response to the condition of the positioning of the second switch in its first position when the first switch is in its second position; and timing circuit means for precluding the coupling by the first circuit means after the control means has coupled its output to a source of electrical power for a predetermined period of time.
Claim 2
Dependent Claim
230 words
A power control for an electrical load in a motor vehicle comprising: a motor vehicle electrical load circuit; control means, having a control input, a load input and an output, the load input being coupled to a source of electrical power, for coupling its output to its load input when its control input is coupled to a source of electrical power; a first switch operable in a first position to couple the control input of the control means to a source of electrical power and in a second position to decouple the control input of the control means from a source of electrical power; a second switch operable in a first position to couple the output of the control means to the load circuit and in a second position to decouple the output of the control means from the load circuit; first circuit means, responsive to the positioning of the sEcond switch and coupled from the second switch, for coupling a source electrical power to the control input of the control means in response to the condition of the positioning of the second switch in its first position when the first switch is in its second position; and timing circuit means for precluding the coupling by the first circuit means after the control means has coupled its output to a source of electrical power for a predetermined period of time.
Claim 3
Dependent Claim
15 words
The control of claim 1 in which the load circuit comprises an exterior lighting circuit.
Claim 4
Dependent Claim
32 words
The control of claim 2 in which the first switch is the motor vehicle ignition switch and the second switch is a switch in series with the motor vehicle exterior lighting circuit.
Claim 5
Dependent Claim
13 words
The control of claim 3 in which the control means is a relay.
Claim 6
Dependent Claim
27 words
The control of claim 4 in which the first circuit means includes a first transistor which is conductive when the second switch is in its first position.
Claim 7
Dependent Claim
33 words
The control of claim 5 in which the first circuit means includes a second transistor, in series with the first transistor, which is conductive when the first switch is in its second position.
Claim 8
Dependent Claim
84 words
The control of claim 6 in which the timing circuit means includes an SCR, whose anode is coupled to the base of the second transistor of the first circuit means and whose cathode is coupled to ground, and a resistor-capacitor charging network coupled from the output of the control means to the gate of the SCR, the charging network charging to a sufficient level after the predetermined time to gate the SCR on, precluding conduction of the second transistor of the first circuit means.
Claim 9
Dependent Claim
27 words
The control of claim 7 in which the charging network of the timing circuit means is coupled to the gate of the SCR through a unijunction transistor.
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) | 1978-04-28 | 1978-10-28 | 1979-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-28 | 1982-10-28 | 1983-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-28 | 1986-10-28 | 1987-04-29 | $7700.00 | Window Closed / Lapsed |