Patent US3749447A successfully refreshed from Google Patents.
US3749447A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vehicle safety switch with removable dielectric plug
Assignee: Individual
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Filing: 1971-09-20
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Granted: 1973-07-31
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Expires: 1991-09-20
Abstract
Abstract Various methods of grounding and stopping engines having an electrical ignition system are known. In this invention a device is introduced into such a system whereby it is grounded by normally closed switch contacts until these contacts are separated by the insertion of a dielectric key. The contacts are wired into the ignition system and the switch housing is affixed to the dashboard and steering column of the vehicle such as a snowmobile so that the withdrawal of the key causes the contacts to engage and instantly grounds and stops the engine.
Inventors
- 👤 R Renaud
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:49
CPC Classifications
H; H01; H01H; H01H27/00; H01H1/00; H01H1/12; H01H1/14; H01H1/24; H01H1/26
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
166 words
In an electrical ignition system for a motorized vehicle having a positive feed wire connected to an engine spark plug and a negative ground wire, in combination, a safety switch comprising a tube adapted to axially receive a dielectric key therein, a pair of conductive contact elements secured to said tube and in electrical insulating relationship to one another and to said tube, said contact elements being connected to a respective positive feed wire and/ or a negative ground wire, said contact elements further having contact portions normally in electrical contact engagement with each other, one of said contact elements extending beyond an end of said tube and having a portion of said key when positioned within said tube whereby said one contact is displaced by said key to separate said electrical contact engagement with said other contact element, said electrical contact engagement being resumed when said elongated key is no longer in frictional contact with said one contact element to render the ignition system inoperable.
Claim 2
Dependent Claim
166 words
In an electrical ignition system for a motorized vehicle having a positive feed wire connected to an engine spark plug and a negative ground wire, in combination, a safety switch comprising a tube adapted to axially receive a dielectric key therein, a pair of conductive contact elements secured to said tube and in electrical insulating relationship to one another and to said tube, said contact elements being connected to a respective positive feed wire and/ or a negative ground wire, said contact elements further having contact portions normally in electrical contact engagement with each other, one of said contact elements extending beyond an end of said tube and having a portion of said key when positioned within said tube whereby said one contact is displaced by said key to separate said electrical contact engagement with said other contact element, said electrical contact engagement being resumed when said elongated key is no longer in frictional contact with said one contact element to render the ignition system inoperable.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-30 | 1977-01-29 | 1977-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-30 | 1981-01-29 | 1981-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-30 | 1985-01-29 | 1985-07-31 | $7700.00 | Window Closed / Lapsed |