Electric starting motor lock-out system

Claim 2

In combination with an electric starting system for cranking an internal combustion engine of the type having a battery; a starter motor; a starter solenoid; and a mechanical switch for connecting the battery in circuit relationship with the solenoid in a first position and disconnecting the battery from circuit relationship with said solenoid in a second position, said mechanical switch operating said starter solenoid which, when energized, couples the starter motor to the engine and connects the battery to the starter motor to crank the engine, wherein the improvement comprises switching means for preventing the flow of current to said solenoid in response to a voltage produced by the collapsing field of said solenoid when said solenoid is deenergized by the placing of said mechanical switch in said second position.

Claim 3

The combination as recited in claim 1 wherein said switching means comprises a first switching circuIt having at least one transistor switch in circuit relationship with said mechanical switch, said battery, and said solenoid, said transistor having an ON state and on OFF state, said OFF state preventing the energization of said solenoid; and an SCR switching circuit in circuit relationship with said mechanical switch, said first switching circuit and said solenoid, said SCR having a cathode connected to one end of said solenoid through a diode and the other end of said solenoid through a resistor, and said SCR having a gate connected to said other end of said solenoid through a resistor so that when said solenoid is deenergized and a transient voltage appears across said solenoid, said SCR conducts turning said transistor switch OFF whereby said solenoid cannot be energized.

Claim 4

The combination as recited in claim 1 wherein said switching means includes means for rendering said switching means conductive in response to movement of said mechanical switch into a third position.

Claim 5

The combination as recited in claim 2 wherein said switching means includes means for rendering said switching means conductive in response to movement of said mechanical switch into a third position.

Claim 6

In an electric starting system for cranking the engine of a motor vehicle, the combination comprising: a storage battery; an electric starting motor; a solenoid for mechanically coupling said electric starting motor to said engine to crank said engine; electronic switching means having semiconductors connected between said battery and said solenoid for controlling the energization of said solenoid; a manually operable switch having an OFF, ON and START position; and means for controlling the conduction of said semiconductors in response to the positioning of said manually operable switch and in response to a voltage produced by the collapsing field of said solenoid when the current to said solenoid is cut off.

Claim 7

In an electric starting system for cranking the engine of a motor vehicle, the combination comprising: a storage battery; an electric starting motor; a solenoid for mechanically coupling said electric starting motor to said engine to crank said engine; electronic switching means having semiconductors connected between said battery and said solenoid for controlling the energization of said solenoid; a manually operable switch having an OFF, ON and START position; and means for controlling the conduction of said semiconductors in response to the positioning of said manually operable switch and in response to a voltage produced by the collapsing field of said solenoid when the current to said solenoid is cut off.

Claim 8

An electric starting system for cranking an internal combustion engine which comprises: a source of electric power; an electric starting motor; electromechanical means for mechanically coupling said electric starter motor to the engine, and for electrically connecting said electric power source to said electric starting motor to crank the engine, said electromechanical means including a solenoid; switching means connected to said source of electric power, said switching means having a plurality of positions including a START position; first circuit means for controlling the flow of current between said switching means and said solenoid, said first circuit means having an ON state which permits the passage of sufficient current to energize said electromechanical means and an OFF state preventing energization of said electromechanical means; and second circuit means for controlling the state of said first circuit means, said second circuit means adapted to place said first circuit means in the OFF state in response to a voltage produced by the collapsing field of said solenoid when electric power is removed from said inductor, said second circuit means adapted to return said first circuit means to the ON state in response to the placing of said switching means in a preselected position for a predetermined time before returning said switching means to the START position whereby said electric starting motor cannot be energized until said mechanical switch is moved to a preselected position for a predetermined time.

Claim 9

An electric starting system for cranking an internal combustion engine which comprises: a source of electric power; an electric starting motor; electromechanical means for mechanically coupling said electric starter motor to the engine, and for electrically connecting said electric power source to said electric starting motor to crank the engine, said electromechanical means including a solenoid; switching means connected to said source of electric power, said switching means having a plurality of positions including a START position; first circuit means for controlling the flow of current between said switching means and said solenoid, said first circuit means having an ON state which permits the passage of sufficient current to energize said electromechanical means and an OFF state preventing energization of said electromechanical means; and second circuit means for controlling the state of said first circuit means, said second circuit means adapted to place said first circuit means in the OFF state in response to a voltage produced by the collapsing field of said solenoid when electric power is removed from said inductor, said second circuit means adapted to return said first circuit means to the ON state in response to the placing of said switching means in a preselected position for a predetermined time before returning said switching means to the START position whereby said electric starting motor cannot be energized until said mechanical switch is moved to a preselected position for a predetermined time.

Claim 10

An electric starting system as recited in claim 6 wherein said first circuit means for controlling the flow of current to said solenoid is a transistorized switch and said second circuit means for controlling the state of said transistorized switch is a silicon-controlled rectifier the cathode of which is in circuit relationship with said solenoid.

Claim 11

An electric starting system as recited in claim 6 wherein said second circuit means includes a resistance-capacitance network in circuit relationship with the anode of said silicon controlled rectifier and said mechanical switch.

Claim 12

An electric starting system as recited in claim 7 wherein said second circuit means includes a resistance-capacitance network in circuit relationship with the anode of said silicon-controlled rectifier and said mechanical switch.