STARTER INTERLOCK CIRCUIT FOR A SEAT BELT UTILIZATION DETECTOR

• US 3,859,627 A
• Filed: 10/30/1972
• Issued: 01/07/1975
• Est. Priority Date: 10/30/1972
• Status: Expired due to Term

• Current Assignee: Norman G. Quantz
• Original Assignee: Norman G. Quantz
• Inventors: Quantz, Norman G.
• Primary Examiner(s): Waring, Alvin H.
• Application Number:
  US05/302,045
• Time in Patent Office: 799 Days
• Field of Search: 340/52E,278 307/1SB 180/82C
• US Class Current: 180/270
• CPC Class Codes: B60R 2022/4891 preventing use of the vehicle when the seatbelt is not fastened
• CPC Class Codes: B60R 22/48 Control systems, alarms, or interlock systems, for the correct application of the belt or harness

Abstract

A starter interlock circuit for a vehicle which includes a single solenoid having a normally open set of contacts connected to a warning device and a normally closed set of contacts interposed between the starter switch and the starter motor. The solenoid has a coil which is connected to a source of potential through a transistor and a switch so that the solenoid is operated to prevent energization of the starter and to operate the warning device when both the switch and the transistor are conducting. The switch is responsive to a seat belt utilization detector and is closed on improper utilization of the one or more seat belts of the vehicle while the transistor is responsive to a timing circuit which maintains the transistor in a non-conducting condition for a predetermined interval after the ignition of the vehicle is switched off to allow the vehicle operator to operate the starter during that interval.

Claims

1. For a vehicle having an engine with an ignition system, an ignition switch which is closable for energizing the ignition system of said engine and openable for de-energizing the ignition system of said engine, a starter switch, a starter motor, and a seat belt utilization detector including switch means which is conductive on improper utilization of a seat belt for the vehicle and nonconductive on proper utilization of the seat belt for the vehicle a starter interlock circuit comprising:

solenoid switch means having a coil and a pair of contacts which are closed so as to be conductive therebetween when said coil is not energized, said coil being adapted for connection in series with said seat belt utilization detector switch means, said contacts being adapted for connection intermediate and ignition switch and said starter motor so as to provide a current path for energization of said starter motor through said contacts when said contacts are closed; and

timing means including switch means connected in series with said coil and being adapted to connection in series with said seat belt utilization detector switch means, said timing means being adapted to hold said timing means switch means nonconductive for a predetermined time interval after the opening of said ignition switch and to render said timing means switch means conductive after said predetermined time interval;

said coil, said seat belt utilization detector switch means, and said timing means switch means forming a series circuit which is adapted for connection to a source of potential whereby the nonconductive condition of one of said seat belt utilization detector switch means indicative of proper utilization of said seat belt of said vehicle and said timing circuit switch means indicative of a lapse of a time less than said predetermined time interval prevents the energization of said coil whereby said solenoid contacts are closed so that said starter switch is effective to energize said starter motor.

2. A starter interlock circuit according to claim 1 wherein said vehicle has a plurality of seat belt utilization detectors with each seat belt utilization detector including switch means which is conductive on improper utilization of the said seat belt for the vehicle and nonconductive on proper utilization of said seat belt for the vehicle and wherein said starter interlock circuit includes single conductor means for connecting each of said seat belt utilization detector switch means in series with said solenoid switch means and said timing means switch means.

3. A starter interlock circuit according to claim 1 wherein said timing means switch means is a solid state switch having a pair of terminals connected in series with said coil and said seat belt utilization detector switch means and having a control terminal which is responsive to a timing control signal representative of said predetermined time interval for rendering said solid state switch nonconductive between said pair of terminals during said predetermined time interval.

4. A starter interlock circuit according to claim 3 further including a capacitor which is charged when said vehicle engine is operating and which is dischargeable at a predetermined rate subsequent to the opening of said ignition switch, said capacitor being operatively associated with said control terminal of said solid state device for maintaining said solid state device nonconductive between said pair of terminals during a predetermined discharge of said capacitor so as to establish said predetermined time interval.

5. A starter interlock circuit according to claim 1 further including holding means for maintaining said timing means switch means non-conductive after cessation of operation of said engine while said ignition switch is closed.

6. A starter interlock circuit according to claim 5 wherein said vehicle includes an oil pressure switch which is operable in response to a predetermined oil pressure resulting from operation of said engine, and wherein said holding means is responsive to said oil pressure switch so that said holding means is effective, upon operation of said engine as indicated by said oil pressure switch, to hold said timing means switch means non-conductive until said ignition switch is opened.

7. A starter interlock circuit according to claim 6 wherein said timing means switch means is a solid state switch having a pair of terminals connected in series with said coil and said seat belt utilization detector switch means and having a control terminal which is responsive to a timing control signal representative of said predetermined time interval for rendering said solid state switch non-conductive between said pair of terminals during said predetermined time interval.

8. A starter interlock circuit according to claim 7 wherein said holding means is effective to provide a signal to said control terminal of said solid state switch means prior to opening of said ignition switch for rendering said solid state switch non-conductive during the duration of said holding means signal.

9. A starter interlock circuit according to claim 8 wherein said holding means signal is provided at least in part through said ignition switch when said ignition switch is closed.

10. For a vehicle having an engine with an ignition system, an ignition switch which is closable for energizing the ignition system of said engine and openable for de-energizing the ignition system of said engine, a seat belt utilization detector including switch means which is closed on improper utilization of a seat belt for the vehicle and is open on proper utilization of the seat belt for the vehicle, an interlock circuit for preventing the operation of said vehicle comprising:

interlock switch means having a control conductor and a pair of terminals, said interlock switch means being conductive between said interlock switch means terminals when said control conductor is energized, said control conductor being adapted for connection to said seat belt utilization detector switch means, said pair of terminals being adapted for providing a current path for energization of said seat belt utilization responsive means;

timing means having switch means connected to said control conductor and being adapted for connection in series with said seat belt utilization detector switch means, said timing means being adapted to hold said timing means switch means open for a determinable time interval after the opening of said ignition switch; and

said control conductor, said timing means switch means, and said seat belt utilization detector means forming a circuit which is adapted for connection to a source of potential for energizing said control conductor when said seat belt utilization detector switch means and said timing means switch means are closed whereby the open condition of one of said seat belt utilization detector switch means indicative of improper utilization of said seat belts of said vehicle and said timing circuit switch means indicative of a lapse of time less than said predetermined time interval prevents energization of said control conductor to prevent the operation of said vehicle.

11. An interlock circuit according to claim 10 wherein said vehicle has a plurality of seat belt utilization detectors with each seat belt utilization detector including switch means which is conductive on improper utilization of an associated seat belt for the vehicle and non-conductive on proper utilization of the associated seat belt for the vehicle, and wherein said interlock circuit includes single conductor means for connecting each of said seat belt utilization detector switch means in series with said timing means switch means.

12. An interlock circuit according to claim 10 further including holding means for maintaining said timing means switch means nonconductive after cessation of operation of said engine while said ignition switch is closed.

13. For a vehicle having an engine with an ignition system, an ignition switch which is closable for energizing the ignition of said engine and openable for de-energizing the ignition of said engine, and a seat belt utilization detector for indicating the improper utilization of a seaT belt for the vehicle, and interlock for preventing operation of the vehicle comprising:

interlock means responsive to said seat belt utilization detector for preventing the operation of said vehicle when said seat belt utilization detector indicates improper utilization of a seat belt of said vehicle;

holding means for allowing operation of said vehicle after the cessation of operation of said engine while said ignition switch remains closed; and

timing means responsive to the opening of said ignition switch for initiating a predetermined timing period and for allowing the restarting of said engine during said predetermined timing period after said ignition switch is opened.

14. For a vehicle having an engine with an ignition system, an ignition switch which is closable for energizing the ignition of said engine and openable for de-energizing the ignition of said engine, and a seat belt utilization detector for indicating the improper utilization of a seat belt for the vehicle, an interlock for preventing operation of the vehicle comprising:

interlock means responsive to said seat belt utilization detector for preventing the operation of said vehicle when said seat belt utilization detector indicates improper utilization of a seat belt of said vehicle; and

timing means responsive to the opening of said ignition switch for initiating a predetermined timing period and for allowing the restarting of said engine during said predetermined timing period after said ignition switch is opened.