Patent US3590379A successfully refreshed from Google Patents.
US3590379A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Monostable multivibrator pulse frequency meters
Assignee: Individual
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Filing: 1969-07-14
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Granted: 1971-06-29
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Expires: 1989-07-14
Abstract
Abstract A vehicle instrument for providing an indication of engine or vehicle speed includes an indicating meter supplied from a monostable circuit. The monostable circuit is triggered by input pulses derived in dependence upon engine or vehicle speed. The monostable circuit includes two transistors forming the active components thereof, and the input pulses are applied to a side of a capacitor in the monostable circuit connected to the normally nonconducting one of said transistors. The monostable circuit is arranged to supply pulses of predetermined width and height product to the meter irrespective of the rate of occurrence of the input pulses.
Inventors
- 👤 Bernard F Fellerman
- 👤 Henry S Marro
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 02:09
CPC Classifications
G; G01; G01R; G01R23/00; G01R23/02; G01R23/06; G01R23/09
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
206 words
A pulse frequency circuit comprising a monostable circuit for supplying pulses to a current averaging device in response to input pulses having a frequency to be measured, and first and second terminals intended to be connected across a direct current supply, the monostable circuit including a first transistor connected between the first terminal and a first collector resistor connected to the second terminal, a second transistor connected between the first terminal and one side of the current averaging device, means connecting the other side of the current averaging device to the second terminal, a connection between the collector of the first transistor and the base of the second transistor, a capacitor having one side connected to the base of the first transistor, a unidirectional conducting device connected between the other side of the said capacitor and the collector of the second transistor arranged to allow current to flow towards the collector of the second transistor, a first resistance means connected between the one side of the said capacitor and said second terminal, second resistance means connected between the other side of the capacitor and said second terminal, and means for applying the input pulses between the said other side of the capacitor and the first terminal.
Claim 2
Dependent Claim
206 words
A pulse frequency circuit comprising a monostable circuit for supplying pulses to a current averaging device in response to input pulses having a frequency to be measured, and first and second terminals intended to be connected across a direct current supply, the monostable circuit including a first transistor connected between the first terminal and a first collector resistor connected to the second terminal, a second transistor connected between the first terminal and one side of the current averaging device, means connecting the other side of the current averaging device to the second terminal, a connection between the collector of the first transistor and the base of the second transistor, a capacitor having one side connected to the base of the first transistor, a unidirectional conducting device connected between the other side of the said capacitor and the collector of the second transistor arranged to allow current to flow towards the collector of the second transistor, a first resistance means connected between the one side of the said capacitor and said second terminal, second resistance means connected between the other side of the capacitor and said second terminal, and means for applying the input pulses between the said other side of the capacitor and the first terminal.
Claim 3
Dependent Claim
17 words
A pulse frequency meter according to claim 1, in which said unidirectional conducting device is a diode.
Claim 4
Dependent Claim
20 words
A pulse frequency device according to claim 1, including a voltage limiting means connector between said first and second terminals.
Claim 5
Dependent Claim
63 words
A pulse frequency meter according to claim 3, including a third terminal to which the direct current supplY is intended to be connected, third resistance means connected between said third and second terminals through which said direct current supply is connected to said second terminal, and said first resistance means being connected between said one side of said capacitor and said third terminal.
Claim 6
Dependent Claim
43 words
A pulse frequency circuit according to claim 1, including input circuit means to which said input signals are supplied, said input circuit means including a squaring circuit arranged to supply square wave pulses to said monostable circuit in response to said input signals.
Claim 7
Dependent Claim
30 words
A pulse frequency circuit according to claim 5, in which the input circuit means includes resistance means arranged to increase the input-impedance of the input circuit to a high value.
Claim 8
Dependent Claim
42 words
A shaft revolution counter including the pulse frequency circuit according to claim 1, and an input signal generator arranged to respond to revolutions of a shaft to generate said input pulses at a frequency in dependence upon the revolutions of the shaft.
Claim 9
Dependent Claim
38 words
A vehicle engine tachometer for a vehicle having an ignition system including the pulse frequency circuit according to claim 1, and an input signal generator arranged to be initiated by said ignition system to produce said input pulses.
Claim 10
Dependent Claim
44 words
A vehicle engine tachometer for a vehicle having an ignition system including a pulse-frequency circuit according to claim 1, and an input circuit arranged to be connected to a contact breaker in a distributor of the ignition system and to provide said input pulses.
Claim 11
Dependent Claim
44 words
A vehicle engine tachograph including a pulse frequency circuit according to claim 1 and an electrical position control system for a speed-indicating stylus of the tachograph in which the control system is arranged to be controlled by an output of the said averaging device.
References Cited (Backward Citations)
GB919421A
Cited
US3303353A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-06-28 | 1974-12-28 | 1975-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-28 | 1978-12-28 | 1979-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-28 | 1982-12-28 | 1983-06-29 | $7700.00 | Window Closed / Lapsed |