US3554177A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic vacuum advance for an ignition system
Assignee: Motorola Solutions Inc
•
Filing: 1968-11-21
•
Granted: 1971-01-12
•
Expires: 1988-11-21
Abstract
Abstract A vacuum servodevice connected to an internal combustion engine is operated in accordance with engine load to vary the position of a core electrically coupling first and second windings of a transformer. By changing the coupling between the windings the output of the transformer is changed. This variable output from the transformer is used to control the conduction of a transistor amplifier which provides a modulating bias on a potential representing ignition advance relative to engine r.p.m. which is connected to the gate of a high sensitivity silicon-controlled rectifier (SCR) which acts as a voltage level detector. The SCR is triggered when the modulated potential reaches a given level providing a firing pulse to discharge the ignition capacitor. The time required for the modulated potential to reach this triggering level varies according to engine r.p.m. and vacuum.
Inventors
- 👤 Arthur G Hufton
- 👤 Peter Dogadko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 08:02
CPC Classifications
F; F02; F02P; F02P5/00; F02P5/04; F02P5/145; F02P5/155; F02P5/05; F02P5/10; F02P5/103; F02P7/00; F02P7/02; F02P7/03; F02P7/035; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/40
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
222 words
A capacitor discharge ignition system for An internal combustion engine having pulse generator means driven in synchronism with the engine for producing electrical pulses, including in combination, trigger circuit means including a semiconductor having a control electrode for operating the same, first circuit means coupling the pulses from the pulse generator means to the control electrode of said semiconductor, said trigger circuit means being responsive to the pulses on the control electrode of said semiconductor reaching a given level to operate the same to discharge the ignition capacitor thereby producing an ignition pulse for the engine, the generated pulses reaching said given level in a timed relation to the engine r.p.m. to provide ignition timing, second circuit means connected to the junction of said first circuit means and the control electrode of said semiconductor for establishing a direct current bias on the control electrode, and vacuum controlled voltage generator means connected to said second circuit means, said vacuum-controlled means being responsive to the engine vacuum under changing engine loads to vary the direct current bias in said second circuit means, hence on the control electrode of said semiconductor thereby varying the time required for the pulses from the pulse generator means to reach the given level to discharge the ignition capacitor so the ignition timing depends on both engine r.p.m. and vacuum.
Claim 2
Dependent Claim
222 words
A capacitor discharge ignition system for An internal combustion engine having pulse generator means driven in synchronism with the engine for producing electrical pulses, including in combination, trigger circuit means including a semiconductor having a control electrode for operating the same, first circuit means coupling the pulses from the pulse generator means to the control electrode of said semiconductor, said trigger circuit means being responsive to the pulses on the control electrode of said semiconductor reaching a given level to operate the same to discharge the ignition capacitor thereby producing an ignition pulse for the engine, the generated pulses reaching said given level in a timed relation to the engine r.p.m. to provide ignition timing, second circuit means connected to the junction of said first circuit means and the control electrode of said semiconductor for establishing a direct current bias on the control electrode, and vacuum controlled voltage generator means connected to said second circuit means, said vacuum-controlled means being responsive to the engine vacuum under changing engine loads to vary the direct current bias in said second circuit means, hence on the control electrode of said semiconductor thereby varying the time required for the pulses from the pulse generator means to reach the given level to discharge the ignition capacitor so the ignition timing depends on both engine r.p.m. and vacuum.
Claim 3
Dependent Claim
54 words
The capacitor discharge ignition system of claim 1 wherein said vacuum-controlled voltage generator means includes a vacuum servo, a potentiometer having a wiper arm and a potential source connected thereto, said wiper arm being connected to said vacuum servo and being moved by the same to produce a potential proportional to the engine vacuum.
Claim 4
Dependent Claim
114 words
The capacitor discharge ignition system of claim 1 wherein said vacuum-controlled voltage generator means comprises oscillating circuit means including piezoelectric means for establishing the output frequency thereof, integrating circuit means connected to the output of said oscillating circuit means and having a voltage output dependent on the input frequency from said oscillator circuit means, and transducer means responsive to engine vacuum connected to said piezoelectric means so the mechanical motion thereof in response to changes in engine vacuum strains said piezoelectric means to change the frequency of the same thereby varying the output frequency of said oscillating circuit means to vary the output potential of said integrating circuit means in accordance with engine load.
Claim 5
Dependent Claim
92 words
The capacitor discharge ignition system of claim 1 wherein said vacuum-controlled voltage generator means includes amplifier circuit means including a strain sensitive semiconductor having a mechanical input for modulating the bias thereon, transducer means responsive to engine vacuum, and means connecting said transducer means to said mechanical input of said semiconductor, said transducer means responding to changes in the engine load to vary the strain on said semiconductor through said mechanical input thereby changing the bias thereon to regulate the output potential of said amplifier circuit means in accordance with engine vacuum.
Claim 6
Dependent Claim
95 words
The capacitor discharge ignition system of claim 1 wherein said second circuit means includes an electron control device having input, output and control electrodes, with the control electrode of said semiconductor being connected to said output electrode of said electron control device, a potential source coupled to said input electrode, and said vacuum-controlled voltage generator means being connected to said control electrode thereof, said vacuum-controlled means being responsive to engine vacuum to produce a potential to control the conduction of said electron control device thereby varying the bias on the control electrode of said semiconductor.
Claim 7
Dependent Claim
142 words
The capacitor discharge ignition system of claim 1 wherein said vacuum-controlled means includes oscillator means, a vacuum servo device and a transformer haVing primary and secondary windings and a core magnetically coupling said windings to one another, said oscillator means being connected to said primary winding, said first circuit means being connected to said secondary winding, and said core being connected to said vacuum servo device, whereby said vacuum servo device responds to changes in engine load to move said core within said transformer thereby varying the magnet coupling between said primary and secondary windings to vary the output from said transformer, said output varying the direct current bias in said second circuit means to provide a potential which modulates the pulses from the pulse generator means to provide electronic advance for the ignition system, dependent on both engine vacuum and r.p.m.
Claim 8
Dependent Claim
95 words
The capacitor discharge ignition system of claim 1 wherein said semiconductor is a first silicon-controlled rectifier having input, output and control electrodes, said control electrode being coupled to said second circuit means, and said trigger circuit means further includes a second silicon-controlled rectifier having input, output and control electrodes, said control electrode being connected to the output electrode of said first silicon-controlled rectifier, said input electrode being connected to the ignition capacitor, and said output electrode being connected to the high voltage transformer of the ignition system for producing a firing pulse for the engine.
References Cited (Backward Citations)
US3277875A
Cited
US3356896A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-01-11 | 1974-07-13 | 1975-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-11 | 1978-07-13 | 1979-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-11 | 1982-07-13 | 1983-01-12 | $7700.00 | Window Closed / Lapsed |