Seat belt system for automotive vehicles

Abstract

The circuit of this invention provides a safety belt system for both shoulder and seat belts which require the driver and any passengers to positively fasten the seat and shoulder harness in a sequential manner in order for the automobile to be started. After the engine is started, disconnection of any belt or harness causes a buzzer or like alarm to be actuated. The circuit is shown as being operable with either of two relay systems. One system uses a latching relay the other uses a stepping relay.

What is claimed is: 
     
       1. A seat belt system for automotive vehicles and the like in which there is provided a plurality of seat belts arranged as pairs with each seat belt having at least one retractor providing a portion of an interlock system requiring said seat belt to be extended after the seat is occupied in order to permit the vehicle's starter solenoid to be actuated by a current supplied by a battery carried in said vehicle, said system including: (a) a plurality of seat belts arranged as pairs, one pair of belts for the driver and the other pairs for potential passengers with each pair positioned and secured to the vehicle so as to accommodate one occupant when seated on a seat of the vehicle; (b) at least one retractor associated with each seat belt pair and adapted to retain one of said belts of the pair, said retractor secured to the vehicle so that said associated seat belt when moved to and from an extended condition causes a cam operatively connected to said retractor to separately engage one of a pair of switches associated therewith so that with the retractor in repose condition a first switch is closed and the second switch is open and when the retractor is moved to the extended condition the moved cam disengages from engagement with the first switch which opens while the moved cam engages the second switch and causes it to be closed; (c) an ignition relay having a switch which is actuated by a holding coil which when energized closes said switch and establishes a conductive circuit from the vehicle battery to the starter solenoid; (d) a starter logic including a key-operated ignition switch and the ignition relay, said starter logic being actuated when the key is turned and to an electrical current to be fed from said ignition switch to the driver's seat retractor and from this retractor only when the retractor is extended to cause the first associated switch to be opened and the second associated switch to be closed, and in the absence of additional passengers said electrical current to be conducted to one side of said ignition relay coil, said electrical current at the same time being fed to the second switch of the next passenger's seat belt retractor; (e) a plurality of seat switches carried by the vehicle and associated with the seat so that one of said seat switches is associated with each seat belt pair and the retractor used with the belt pair; (f) a plurality of relay logics with an individual logic being exclusively actuated by each associated seat switch, each of said relay logics having two electrically actuated states, the first state being effective when said seat in unoccupied and the second state being effective when said seat is occupied said second state establishing a circuit between said second switch of the retractor and ignition relay holding coil, said logic returnable to its first state only when the seat again becomes unoccupied, each seat switch being actuated by the weight of an occupant on the seat immediately above to open one switch portion thereof and by closing a second switch to transfer a voltage to said relay logic through said retractor, and with the absence of an occupant the switch returns to its "at rest" condition with the voltage sent through the first switch and with the second switch moving to open condition; (g) an audible signal having a first side connected to a battery source and the other to a ground source, the first side being connected when the ignition switch is closed; (h) a conductive circuit from a ground source to the audible signal and ground side of the ignition relay coil, said conductive circuit being established only when the seat belts to all occupied seats are connected, this circuit when connected providing a conductive path to the ground side of the ignition relay coil to energize this coil and close the relay switch to energize the starter solenoid, said circuit also connected to the first side of the audible signal and when conductive renders the signal ineffective, this circuit including a by-pass switch associated with each passenger seat switch, the seat switch of the driver having no by-pass switch, said by-pass switch being normally closed to provide a conductive path portion of the circuit until opened by the weight of a passenger on the switch, and (i) a series circuit extending from the driver's seat switch and retractor to the associated relay logic, said circuit connected to the retractor switch and associated logic so that the actuation of a seat switch with the retractor in its "at rest" condition will move the associated relay logic from its "at rest" state to its second state by a voltage fed to and through the actuated seat switch and through the closed first switch of the retractor to the relay logic, the relay logic remaining in this state during the occupation of the seat and connecting of the associated seat belt, and with the ground conductive circuit estabished by the connecting of the associated seat belt of each occupied seat to establish a conductive path around the opened by-pass switch of each occupied seat, the disconnection of any seat belt of an occupied seat causing a discontinuance of the ground circuit and actuation of the audible signal, and when the occupant leaves the seat the switch is closed to feed a voltage to the relay logic to reset this logic to its first "at rest" state. 
     
     
       2. A seat belt system as in claim 1 in which the relay means associated with each of the seats is a latching relay. 
     
     
       3. A seat belt system as in claim 1 in which the relay means associated with the driver's seat and retractor is a stepping relay. 
     
     
       4. A seat belt system as in claim 1 in which the retractors are moved rotatably clockwise and counterclockwise with and against a tension means and the cam carried thereby is attached to the retractor and is moved therewith to engage only one of the two switches when the retractor is at one of the two extremes of retractor movement. 
     
     
       5. A seat belt system as in claim 1 in which the seat switch for the driver is a single-pole double-throw switch actuated by a spring-biased plunger attached to a portion of the seat and the seat switches for all possible passenger occupied seats are three-pole, double-throw switches actuated by a spring-biased plunger attached to a portion of the seat. 
     
     
       6. A seat belt system as in claim 1 in which each occupant seat space has two retractors associated with a seat switch, each retractor having a cam disposed to actuate at its two extremes of movement only one of two switches associated with the retractor, the first switches of these retractors being series connected in one circuit and the second switches of the retractors being series connected in a second circuit so that the two retractors, to render the audible signal ineffective must be used to provide a like arrangement of the cams and switches in both retractors. 
     
     
       7. A seat belt system as in claim 6 in which the seat belt pairs have conductive means carried therein and end connectors disposed to be engaged to provide the conductible path through the connected pair of belts. 
     
     
       8. A seat belt system as in claim 1 in which the audible signal is a buzzer.  .Iadd. 9. A control and indicator system for use with a motor vehicle provided with a source of direct current, a starter circuit, an ignition circuit, an ignition switch actuable from a normally open position to a START position connecting said source to said starter circuit and said ignition circuit and biased to return from said START position to a RUN position connecting said source to said ignition circuit, seat occupancy responsive switch means and seat belt in-use responsive switch means, said control and indicator system comprising: first logic means connected with said seat switch means and said seat belt switch means for producing a START logic level output when and only when said seat occupancy responsive switch means are actuated prior to actuation of said seat belt in-use responsive switch means, said logic means producing a START logic level output when said seat belt in-use responsive switch means are deactuated or when said seat occupancy responsive switch means are deactuated,   second logic means connected with said first logic means and said starter and ignition circuit for producing a START logic level output in response to actuation of said ignition switch to said START position subsequent to production of said START logic level output from said first logic means,   third logic means for controlling energization of said starter circuit and permitting energization of said starter circuit only in response to said START logic level output of said second logic means,   visual indicator means,   audible indicator means,   fourth logic means responsive to the output of said first logic means for energizing said indicator means in response to said START logic level   
     
     
        output of said first logic means. .Iaddend. .Iadd. 10.  A control and indicator system for use with a motor vehicle provided with a source of direct current, a starter circuit, an ignition circuit, an ignition switch actuable from a normally open position to a START position connecting said source to said starter circuit and said ignition circuit and biased to return from said START position to a RUN position connecting said source to said   ignition circuit, seat occupancy responsive switch means and seat belt in-use responsive switch means, said control and indicator system comprising: first logic means connected with seat switch means and said seat belt switch means for producing a START logic level output when and only when said seat occupancy responsive switch means are actuated prior to actuation of said seat belt in-use responsive switch means, said first logic means producing a START logic level output when said seat belt in-use responsive switch means are deactuated or when said seat occupancy responsive switch means are deactuated,   second logic means normally producing said START logic level output, but actuable to produce a said START logic level output in response to a START logic level output from said first logic means,   third logic means for permitting energization of said starter circuit in response to said START logic level output of said second logic means,   visual indicator means connected to said source when said ignition switch is in said RUN position,   audible indicator means connected to said source in parallel with said ignition switch,   fourth logic means responsive to the output of said first logic means for energizing said visual and audible indicator means in response to said START logic level output of said first logic means..Iaddend.