Patent US3745461A successfully refreshed from Google Patents.
US3745461A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for measuring speed of rotation including a circuit failure detector
Assignee: Denso Corp
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Filing: 1972-05-05
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Granted: 1973-07-10
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Expires: 1992-05-05
Abstract
Abstract A device for measuring speed of rotation comprising an a.c. tachometer generator and an oscillator which oscillates in synchronism with the output of the generator when the generator is in operation and which oscillates at its free-running frequency when the generator is not in operation. In the device, means are provided for forcedly ceasing the oscillation of the oscillator in the event of occurrence of disconnection or shortcircuit of the power generating coil of the generator, and a detector detects the de-energization of the oscillator.
Inventors
- 👤 H Wakamatsu
- 👤 T Kurebayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:35
CPC Classifications
G; G01; G01P; G01P3/00; G01P3/42; G01P3/44; G01P3/48; G01P3/4802
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
124 words
A device for measuring speed of rotation comprising an a.c. tachometer generator including a power generating coil for generating a voltage signal responsive to the revolutions of a rotary member, oscillation means oscillating in synchronism with the output of said generator when said generator is in operation and oscillating at a predetermined free-running frequency when said generator is not in operation, a first means connected in circuit between said a.c. generator and said oscillation means for de-energizing said oscillation means in the event of occurrence of a disconnection or short-circuit trouble on the power generating coil in said generator, and a second means connected in circuit with said oscillation means for detecting the appearance or disappearance of the oscillation output from said oscillation means.
Claim 2
Independent Claim
124 words
A device for measuring speed of rotation comprising an a.c. tachometer generator including a power generating coil for generating a voltage signal responsive to the revolutions of a rotary member, oscillation means oscillating in synchronism with the output of said generator when said generator is in operation and oscillating at a predetermined free-running frequency when said generator is not in operation, a first means connected in circuit between said a.c. generator and said oscillation means for de-energizing said oscillation means in the event of occurrence of a disconnection or short-circuit trouble on the power generating coil in said generator, and a second means connected in circuit with said oscillation means for detecting the appearance or disappearance of the oscillation output from said oscillation means.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-09 | 1977-01-08 | 1977-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-09 | 1981-01-08 | 1981-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-09 | 1985-01-08 | 1985-07-10 | $7700.00 | Window Closed / Lapsed |