Actuating and monitoring device for inflatable occupant restraint system

Claim 2

In a safety system for a vehicle having a battery and an ignition switch connected to said battery and said safety system having a safety device actuated by an electrically energizable actuator means comprising normally open sensor switch means for, when closed, completing a series circuit with said actuator means, power supply circuit means for connecting said series circuit with said ignition switch across said battery for providing a primary battery supplied voltage across said series circuit of a magnitude normally at least greater than a desired magnitude sufficient to energize said actuator means when said sensor means is closed, said power supply circuit means including a capacitor, charging circuit means for continuously subJecting said capacitor to the voltage derived from said battery to charge said capacitor to a stored voltage normally less than the magnitude of said primary voltage but at least equal to said desired magnitude, circuit means connecting said capacitor across said series circuit to define a discharge circuit including said series circuit for discharging said capacitor therethrough only when said sensor means is closed and said primary voltage is less than said stored voltage, indicator means connected to said series circuit means, and control circuit means connected to said indicator means for energizing said indicator means when the magnitude of said primary voltage decreases below that of said desired magnitude while said sensor switch means is open to provide an indication representative thereof.

Claim 3

In a safety system as set forth in claim 1, wherein said control circuit means includes circuit means connected across said series circuit for continuously developing a voltage signal representative of the magnitude of said primary voltage, said developing circuit means including semiconductor means responsive to said voltage signal for energizing said indicator means when said primary voltage decreases to a magnitude less than said desired magnitude.

Claim 4

In a safety system as set forth in claim 2, wherein said indicator means includes a lamp having a filament and circuit means for testing the electrical continuity of said filament prior to completion of initially charging said capacitor.

Claim 5

In a safety system as set forth in claim 2, including connector means for connecting said sensor switch means with said actuator means to complete said series circuit, and connector switch means having a closed condition representative that said connector means is not connected to complete said series circuit, said connector switch being connected to energize said indicator means when said connector switch means is in its closed condition.

Claim 6

In a safety system for a vehicle having a battery and a three position ignition switch connected to said battery and having an off position, a start position for starting the vehicle and a run position for normal vehicle operation and wherein said safety system employs an inflatable confinement having a collapsed condition and an expanded condition for restraining movement of a vehicle occupant during a collision comprising sensor switch means for, when closed, completing an electrical circuit with said battery through said ignition switch when in its run position for energizing actuator means for causing said confinement to be inflated to its expanded condition, a capacitor, charging circuit means for applying charging current derived from said battery through said ignition switch when in its run position to charge said capacitor to a stored voltage approaching that of the battery voltage, series circuit means connecting said capacitor with said sensor switch means for discharging said capacitor through said sensor switch means to energize said actuator means only when said sensor switch means is closed and said battery voltage is less than said stored voltage, indicator means connected to said series circuit means, and circuit monitoring means connected to said series circuit means and said indicator means for continuously monitoring said battery voltage when said ignition switch is in its run position and energizing said indicator means when the magnitude of the battery voltage decreases to a magnitude less than a predetermined magnitude.

Claim 7

In a safety system for a vehicle having a battery and a three position ignition switch connected to said battery and having an off position, a start position for starting the vehicle and a run position for normal vehicle operation and wherein said safety system employs an inflatable confinement having a collapsed condition and an expanded condition for restraining movement of a vehicle occupant during a collision comprising sensor switch means for, when closed, completing an electrical circuit with said battery through said ignition switch when in its run position for energizing actuator means for causing said confinement to be inflated to its expanded condition, a capacitor, charging circuit means for applying charging current derived from said battery through said ignition switch when in its run position to charge said capacitor to a stored voltage approaching that of the battery voltage, series circuit means connecting said capacitor with said sensor switch means for discharging said capacitor through said sensor switch means to energize said actuator means only when said sensor switch means is closed and said battery voltage is less than said stored voltage, indicator means connected to said series circuit means, and circuit monitoring means connected to said series circuit means and said indicator means for continuously monitoring said battery voltage when said ignition switch is in its run position and energizing said indicator means when the magnitude of the battery voltage decreases to a magnitude less than a predetermined magnitude.

Claim 8

In a safety system as set forth in claim 5, wherein said indicator means comprises a lamp and lamp test circuit means connected thereto and responsive to said start position of said ignition switch for testing said lamp for electrical continuity.

Claim 9

In a safety system as set forth in claim 6, wherein said lamp test circuit means includes circuit means for connecting said lamp across said battery through said ignition switch when in its start position.

Claim 10

In a safety system for a vehicle havinG a battery and an ignition switch connected to said battery and said safety system having a safety device actuated by an electrically energizable actuator means comprising sensor switch means for, when closed, completing a series circuit with said actuator means; power supply circuit means for connecting said series circuit with said ignition switch across said battery for providing a primary battery supplied voltage across said series circuit of a magnitude normally at least greater than a desired magnitude sufficient to energize said actuator means when said sensor means is closed, said power supply circuit means including a capacitor, charging circuit means being continuously subjected to charging voltage derived from said battery through said ignition switch to charge said capacitor to a stored voltage normally less than the magnitude of said primary voltage but at least equal to said desired magnitude, circuit means connecting said capacitor across said series circuit to define a discharge circuit including said series circuit for discharging said capacitor therethrough only when said sensor means is closed and said primary voltage is less than said stored voltage, indicator means connected to said circuit means, and circuit monitoring means connected to said circuit means for continuously monitoring at least a portion of said discharge circuit and energizing said indicator means when the magnitude of the available voltage across said portion is of a magnitude less than said desired magnitude.

Claim 11

In a safety system for a vehicle havinG a battery and an ignition switch connected to said battery and said safety system having a safety device actuated by an electrically energizable actuator means comprising sensor switch means for, when closed, completing a series circuit with said actuator means; power supply circuit means for connecting said series circuit with said ignition switch across said battery for providing a primary battery supplied voltage across said series circuit of a magnitude normally at least greater than a desired magnitude sufficient to energize said actuator means when said sensor means is closed, said power supply circuit means including a capacitor, charging circuit means being continuously subjected to charging voltage derived from said battery through said ignition switch to charge said capacitor to a stored voltage normally less than the magnitude of said primary voltage but at least equal to said desired magnitude, circuit means connecting said capacitor across said series circuit to define a discharge circuit including said series circuit for discharging said capacitor therethrough only when said sensor means is closed and said primary voltage is less than said stored voltage, indicator means connected to said circuit means, and circuit monitoring means connected to said circuit means for continuously monitoring at least a portion of said discharge circuit and energizing said indicator means when the magnitude of the available voltage across said portion is of a magnitude less than said desired magnitude.

Claim 12

In a vehicle having a battery, an ignition switch and a safety device which is actuatable by an electrically energizable actuator means, a circuit for effecting electrical energization of said actuator means, said circuit being connected with said battery through said ignition switch, said circuit comprising a capacitor and means for continuously subjecting said capacitor to the voltage of said battery upon closure of said ignition switch, sensor switch means connected to said capacitor and said electrically energizable actuator means for effecting discharge of said capacitor through said sensor switch means and said electrically energizable actuator means upon closing of said sensor switch means means connected to said energizing circuit permitting discharge of said capacitor only when said battery voltage decays below a predetermined value and an indicator light and switching means circuit operatively connected with said indicator light and said energizing circuit for actuating said indicator light when the voltage of the battery decays below said predetermined level.

Claim 13

In a vehicle having a battery, an ignition switch and a safety device which is actuatable by an electrically energizable actuator means, a circuit for effecting electrical energization of said actuator means, said circuit being connected with said battery through said ignition switch, said circuit comprising a capacitor and means for continuously subjecting said capacitor to the voltage of said battery upon closure of said ignition switch, sensor switch means connected to said capacitor and said electrically energizable actuator means for effecting discharge of said capacitor through said sensor switch means and said electrically energizable actuator means upon closing of said sensor switch means means connected to said energizing circuit permitting discharge of said capacitor only when said battery voltage decays below a predetermined value and an indicator light and switching means circuit operatively connected with said indicator light and said energizing circuit for actuating said indicator light when the voltage of the battery decays below said predetermined level.