Theft prevention starter system for a vehicle
US4157479A · kind A · utility
Inventor
Key dates
| Filing date | Oct 25, 1977 |
| Grant date | Jun 5, 1979 |
| Priority date | — |
| Expiry date | Oct 25, 1997 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60R25/045
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A theft prevention starter system for a motorized vehicle is disclosed which operates to thwart unauthorized attempts at starting the vehicle's engine. The system includes a starter circuit having a starter switch, a bridge circuit, and an anti-theft switch disposed in series with each other. A key is provided having a pair of resistors mounted thereon that are connected to other resistors when the key is inserted into the vehicle's starter lockswitch to form the bridge circuit. A sensing branch of the bridge circuit is coupled to the anti-theft switch and in the event current flows through the sensing branch, the anti-theft switch will be opened to prevent the activation of the starter motor. Current flow in the sensing branch circuit will be absent if resistors having the proper value of resistance are matched when the key is inserted in the lockswitch. Inserting a key having the improper resistances will result in the flow of current in the sensing branch portion of the bridge circuit which will provide for the immediate opening of the anti-theft switch thereby precluding activation of the starter motor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.