Patent US3790931A successfully refreshed from Google Patents.
US3790931A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filter bypass warning circuit on a motor vehicle
Assignee: Deutz Allis Corp
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Filing: 1972-06-30
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Granted: 1974-02-05
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Expires: 1992-06-30
Abstract
Abstract An electric warning circuit operated by a filter bypass valve operating as a switch.
Inventors
- 👤 J Leveraus
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 05:00
CPC Classifications
B; B01; B01D; B01D35/00; B01D35/14; B01D35/143; B01D35/147; F; F01; F01M; F01M11/00; F01M11/10; F02; F02M; F02M35/00; F02M35/02; F02M35/08; F02M35/09; F16; F16H; F16H57/00; F16H57/04; F16H57/0402; F16H57/0404; F16H59/00; F16H59/68; F16H59/72; F16H61/00; F16H61/12
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
162 words
An electric warning circuit comprising, a hydraulic fluid system including a source of pressurized fluid, a fluid filter and normally closed bypass valves operating as an electric switch in said system, an alarm, a source of electrical energy, a current flow control means connected in series with said alarm for controlling the flow of current through said alarm, a bias circuit connected to said current flow control means and said source of electrical energy including said bypass valve operating as a switch to bias said current flow control means for conduction and energization of said alarm when said valve is in the open position, a starter circuit including a starter switch, a test circuit including a transistor having its emitter connected to ground, a resister connected between the base of said transistor and said starter circuit, a diode connected to said alarm, means connecting the collector of said transistor to said diode to test said alarm when said starter circuit is energized.
Claim 2
Dependent Claim
162 words
An electric warning circuit comprising, a hydraulic fluid system including a source of pressurized fluid, a fluid filter and normally closed bypass valves operating as an electric switch in said system, an alarm, a source of electrical energy, a current flow control means connected in series with said alarm for controlling the flow of current through said alarm, a bias circuit connected to said current flow control means and said source of electrical energy including said bypass valve operating as a switch to bias said current flow control means for conduction and energization of said alarm when said valve is in the open position, a starter circuit including a starter switch, a test circuit including a transistor having its emitter connected to ground, a resister connected between the base of said transistor and said starter circuit, a diode connected to said alarm, means connecting the collector of said transistor to said diode to test said alarm when said starter circuit is energized.
Claim 3
Dependent Claim
28 words
An electrical warning circuit as set forth in claim 1 wherein said current flow control means comprises a second transistor controlling the flow of current through said alarm.
Claim 4
Dependent Claim
57 words
An electrical warning circuit as set forth in claim 1 wherein said flow control means comprises a second transistor, means for connecting said alarm in series with said second transistor across said source of electrical energy, said bypass valve operating as the switch connecting the base of said second transistor to ground when said valve is closed.
Claim 5
Dependent Claim
73 words
An electrical warning circuit as set forth in claim 1 wherein said bias circuit includes a resistor connected in series with said valve operating as a switch across said source of electrical energy, means defining the junction between said switch and said resistor for connection to the base of said second transistor to normally apply ground potential to said second transistor to prevent conduction through said second transistor when said switch is closed.
Claim 6
Dependent Claim
99 words
An electrical warning circuit as set forth in claim 1 wherein said current flow control meanS comprises a second transistor, said bias circuit includes a resistor connected in series with said valve operating as a switch across said source of electrical energy, means defining a junction between said resistor and said valve and means connecting said junction to the base of said second transistor, means insulating a valve element of said valve from ground thereby raising the base potential of said second transistor allowing said second transistor to conduct current and energize said alarm when said valve is open.
Claim 7
Dependent Claim
113 words
An electrical warning circuit as set forth in claim 1 comprising means defining an air filter and an air intake passage, an air pressure switch operating responsive to air pressure in said passage, a second alarm, a second current flow control means connected in series with said second alarm across said source of electrical energy, a second bias circuit connected to said second current flow control means and said source of electrical energy including said air pressure switch to control the bias on said second current flow control means for conduction of current through said second current flow control means and energization of said second alarm when said air pressure switch is open.
Claim 8
Dependent Claim
53 words
In an electrical warning circuit as set forth in claim 1 including a second alarm, a thermal switch connected to a transmission of the vehicle, said thermal switch operating to close when said transmission is overheated to thereby operate said second alarm to indicate to the operator an overheated condition of said transmission.
Claim 9
Dependent Claim
120 words
An electrical warning circuit as set forth in claim 1 including a second alarm, a second transistor connected in series with said second alarm across said source of electrical energy, a bias circuit for controlling the flow of current through said second transistor, a second diode connected in series with said second alarm, and said first transistor across said source of electrical energy, said starter circuit being connected to the base of said first transistor to conduct current through said first and second alarms when said starting circuit is energized. 9 An electrical warning circuit as set forth in claim 6 wherein said second current flow control means comprises a second transistor controlling the flow of current through said alarm.
Claim 10
Dependent Claim
96 words
An electrical warning circuit as set forth in claim 1 wherein said flow control means comprises a second transistor, means connecting said second alarm in series with said second transistor across said source of electrical energy, a resistor and said switch connected in series across said source of electrical energy and in parallel with said second current flow control means and said second alarm, means defining a junction between said resistor and said switch connected to the base of said second transistor to thereby ground the base of said second transistor when said switch is closed.
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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) | 1977-02-04 | 1977-08-06 | 1978-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-04 | 1981-08-06 | 1982-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-04 | 1985-08-06 | 1986-02-05 | $7700.00 | Window Closed / Lapsed |