US4057740A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Constant duty cycle monostable
Assignee: Mallory Inc
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Filing: 1976-08-23
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Granted: 1977-11-08
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Expires: 1996-08-23
Abstract
Abstract A circuit that functions as a monostable multivibrator and has a constant duty cycle regardless of the frequency of the input trigger signal is particularly useful in electronic ignition systems for internal combustion engines.
Inventors
- 👤 Leonard E. Arguello
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 03:16
CPC Classifications
F; F02; F02P; F02P3/00; F02P3/02; F02P3/04; F02P3/045; F02P3/0453; H; H03; H03K; H03K3/00; H03K3/01; H03K3/015; H03K3/02; H03K3/027; H03K3/033; F02P5/00; F02P5/04; F02P5/145; F02P5/155; F02P5/1551
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
147 words
Monostable multivibrator circuit with constant duty cycle comprising: a flip-flop having a first input for switching the flip-flop to a first state, a second input for switching the flip-flop to a second state, and an output; a comparator means coupled to the first input and capable of generting an output signal when an input signal applied thereto reaches a predetermined level; a timing and storage means coupled to the second input of said flip-flop; a charging means coupled to the timing and storage means; and, a discharging means coupled to the timing and storage means and responsive to output signals from the flip-flop, whereby said timing and storage means is charged by said charging means and is discharged responsive to receipt of an output signal from said flip-flop, and whereby said flip-flop produces its output signal responsive to receipt of an output signal from said comparator means.
Claim 2
Dependent Claim
147 words
Monostable multivibrator circuit with constant duty cycle comprising: a flip-flop having a first input for switching the flip-flop to a first state, a second input for switching the flip-flop to a second state, and an output; a comparator means coupled to the first input and capable of generting an output signal when an input signal applied thereto reaches a predetermined level; a timing and storage means coupled to the second input of said flip-flop; a charging means coupled to the timing and storage means; and, a discharging means coupled to the timing and storage means and responsive to output signals from the flip-flop, whereby said timing and storage means is charged by said charging means and is discharged responsive to receipt of an output signal from said flip-flop, and whereby said flip-flop produces its output signal responsive to receipt of an output signal from said comparator means.
Claim 3
Dependent Claim
11 words
Circuit of claim 1 wherein said comparator means comprises a comparator.
Claim 4
Dependent Claim
29 words
Circuit of claim 1 wherein said timing and storage means comprises a capacitor with a first side coupled to the second input, and a second side coupled to ground.
Claim 5
Dependent Claim
46 words
Circuit of claim 3 wherein said charging means comprises a first transistor whose collector is coupled to the first side of the capacitor, whose emitter is coupled through a resistor to a supply voltage, and whose base is coupled through a resistor to a supply voltage.
Claim 6
Dependent Claim
54 words
Circuit of claim 3 wherein said discharging means comprises a second transistor whose collector is coupled to the first side of the capacitor, whose emitter is coupled through a resistor to ground, and whose base is coupled through a resistor to the output of the flip-flop and through additional resistors to a supply voltage.
Claim 7
Dependent Claim
45 words
Circuit of claim 1, wherein said circuit is associated with the ignition for an internal combustion engine, said inputs including the ignition timing pick-up means of said engine, and the outputs from said flip-flop operating the firing means for the spark plugs of said engine.
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) | 1980-11-07 | 1981-05-09 | 1981-11-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-11-07 | 1985-05-09 | 1985-11-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-11-07 | 1989-05-09 | 1989-11-08 | $7700.00 | Window Closed / Lapsed |