US3855984A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Capacitive discharge ignition system having variable capacitance
Assignee: Individual
•
Filing: 1972-11-29
•
Granted: 1974-12-24
•
Expires: 1992-11-29
Abstract
Abstract An ignition system for internal combustion engines utilizing a capacitive discharge to supply energy to the spark plugs. Charging and discharging of the capacitor is controlled by a circuit utilizing a silicon controlled rectifier (SCR) which operates in response to engine driven switching means for turning on and in response to positive back-biasing for turning off. The system includes the capability of connecting additional capacitance into the system for the purpose of supplying additional energy to the spark plugs during engine starting and warmup.
Inventors
- 👤 C Jacobs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 11:11
CPC Classifications
F; F02; F02P; F02P3/00; F02P3/06; F02P3/08; F02P3/0876; F02P3/0884
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
145 words
An ignition system for internal combustion engines comprising: a source of electric power; a first capacitor for storing electric power coupled to the power source; a second capacitor connected in parallel circuit relationship with said first capacitor; normally closed switching means Connected in series circuit relationship with the second capacitor; temperature sensing means operatively associated with said switching means for opening said switching means when engine temperature is above predetermined threshhold value to disconnect said second capacitor from the ignition system; an ignition coil coupled to said first and second capacitors; means coupled to the ignition coil for producing an electric spark; an electronic switch coupled to the first and second capacitor for controlling the discharge and charge of the first and second capacitors; and engine controlled switching means coupled to the electronic switch for periodically operating said switch to produce discharge of the capacitors.
Claim 2
Dependent Claim
145 words
An ignition system for internal combustion engines comprising: a source of electric power; a first capacitor for storing electric power coupled to the power source; a second capacitor connected in parallel circuit relationship with said first capacitor; normally closed switching means Connected in series circuit relationship with the second capacitor; temperature sensing means operatively associated with said switching means for opening said switching means when engine temperature is above predetermined threshhold value to disconnect said second capacitor from the ignition system; an ignition coil coupled to said first and second capacitors; means coupled to the ignition coil for producing an electric spark; an electronic switch coupled to the first and second capacitor for controlling the discharge and charge of the first and second capacitors; and engine controlled switching means coupled to the electronic switch for periodically operating said switch to produce discharge of the capacitors.
Claim 3
Dependent Claim
56 words
An ignition system according to claim 1 including a third capacitor connected in parallel circuit relationship with said first and second capacitors; and circuit means coupled to said third capacitor whereby the charging rate of said third capacitor is controlled such that additional capacitance is only provided in the system at cranking and low engine speeds.
Claim 4
Dependent Claim
43 words
An ignition system according to claim 2 wherein the circuit means includes a resistor connected in parallel circuit relationship with said first and second capacitors, the resistor and third capacitor having a time constant for providing said additional capacitance at said engine speeds.
Claim 5
Dependent Claim
29 words
An ignition system according to claim 1 including means for closing said switching means when engine temperature drops below a second predetermined threshold value lower than said first value.
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) | 1977-12-23 | 1978-06-24 | 1978-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-23 | 1982-06-24 | 1982-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-23 | 1986-06-24 | 1986-12-24 | $7700.00 | Window Closed / Lapsed |