Method of operating a safety device for vehicle occupants

• US 5,068,640 A
• Filed: 04/04/1990
• Issued: 11/26/1991
• Est. Priority Date: 11/16/1987
• Status: Expired due to Fees

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Nitschke, Werner, Taufer, Peter, Burger, Wilfried, Weller, Hugo
• Primary Examiner(s): Noland, Tom
• Application Number:
  US07/466,301
• Time in Patent Office: 601 Days
• Field of Search: 73/865.9, 73/489, 73/495, 73/497, 73/509, 73/517 R, 324/503, 324/537, 324/548, 340/438, 340/457.1, 340/459, 340/635, 340/653, 340/669, 340/584, 340/587, 340/693, 374/141, 280/735, 180/270, 180/282, 180/283, 200/61.58 B, 307/10.1, 307/121, 307/125, 307/130
• US Class Current: 340/438
• CPC Class Codes: B60R 21/017 including arrangements for providing electric power to safety arrangements or their actuating means, e.g. to pyrotechnic fuses or electro-mechanic valves

Abstract

A safety device for vehicle occupants has an operational voltage source, typically the vehicle'"'"'s battery, and a storage device for electrical energy, typically a capacitor. Several tripping devices, typically ignition tablets, are coupled to the storage device and/or the operational voltage source, for actuating inertial restraining devices, such as airbags, belt tighteners or the like. If the storage device fails, each tripping device is connected for a specified period of time to the operational voltage source by a respective switch. Each switch is triggered by an evaluating device. Therefore, if the storage device fails, as long as the operational voltage source is connected to the safety device, each tripping device and, therefore, inertial restraining device can be actuated.

Claims

1. A method of actuating a safety device for a motor vehicle, the safety device including an electric storage device coupled to a voltage source, both the electric storage device and the voltage source being coupled to tripping devices for actuating restraining devices on the motor vehicle, comprising the following steps:

monitoring the electric storage device to determine if it is defective;

if the storage device is defective, interrupting the flow of electric current from the storage device to the tripping devices; and

directing electric current from the voltage source to at least one tripping device for a predetermined period of time to actuate the respective tripping device.

2. A method as defined in claim 1, wherein

the predetermined period of time is the same for each tripping device.

3. A method of actuating a safety device for a motor vehicle, the safety device including an electric storage device coupled to a voltage source, both the electric storage device and the voltage source being coupled to tripping devices for actuating restraining devices on the motor vehicle, comprising the following steps:

monitoring the electric storage device to determine if it is defective;

if the storage device is defective, interrupting the flow of electric current from the storage device to the tripping devices; and

directing electric current from the voltage source to at least one tripping device for a predetermined period of time to actuate the respective tripping device, wherein the predetermined period of time is varied depending upon the respective tripping device to be actuated.

4. A method as defined in claim 3, further comprising the following steps:

measuring the ambient temperature of the safety device; and

basing the predetermined period of time on the temperature measurement.

5. A safety device for actuating a plurality of restraining devices on a motor vehicle, comprising:

a voltage source;

an electric storage device coupled to the voltage source to receive electric energy therefrom;

a plurality of tripping devices, each tripping device being coupled to the voltage source, the electric storage device, and to a respective restraining device, each tripping device being actuated to in turn actuate a respective restraining device by passing electric current from either the voltage source or the electric storage device therethrough;

an acceleration sensor for generating output signals indicative of the acceleration of the vehicle;

an evaluating device coupled to the acceleration sensor and to the tripping devices, the evaluating device being adapted to control the flow of electric current to each respective tripping device in response to the output signals generated by the acceleration sensor, the evaluating device also being coupled to the voltage source and to the electric storage device, the evaluating device being further adapted to determine whether the electric storage device is defective, and to disconnect the electric storage device from the restraining devices in response thereto; and

a plurality of timing elements, each timing element being coupled between the evaluating device and a respective tripping device, each timing element permitting electric current to pass to the respective tripping device for a predetermined period of time to actuate the tripping device.

6. A safety device for actuating a plurality of restraining devices on a motor vehicle, comprising:

a voltage source;

an electric storage device coupled to the voltage source to receive electric energy therefrom;

a plurality of tripping devices, each tripping device being coupled to the voltage source, the electric storage device, and to a respective restraining device, each tripping device being actuated to in turn actuate a respective restraining device by passing electric current from either the voltage source or the electric storage device therethrough;

an acceleration sensor for generating output signals indicative of the acceleration of the vehicle;

an evaluating device coupled to the acceleration sensor and to the tripping devices, the evaluating device being adapted to control the flow of electric current to each respective tripping device in response to the output signals generated by the acceleration sensor, the evaluating device also being coupled to the voltage source and to the electric storage device, the evaluating device being further adapted to determine whether the electric storage device is defective, and to disconnect the electric storage device from the restraining devices in response thereto;

a plurality of timing elements, each timing element being coupled between the evaluating device and a respective tripping device, each timing element permitting electric current to pass to the respective tripping device for a predetermined period of time to actuate the tripping device; and

a temperature sensor coupled to the evaluating device and to the timing elements, the temperature sensor generating output signals indicative of the ambient temperature thereof, and the timing elements being adapted to permit electric current to flow through the respective tripping devices for a predetermined period of time based thereon.

7. An apparatus for actuating a passenger restraint device on a motor vehicle, comprising:

an acceleration sensor mounted on the motor vehicle for generating output signals indicative of the acceleration thereof;

a plurality of tripping devices, each tripping device being coupled to a respective passenger restraint device, each tripping device being actuated by the passage of electric current therethrough to actuate the respective passenger restraint device;

a voltage source coupled to each tripping device to provide electric current thereto to actuate the respective tripping device;

an electric storage device coupled to the voltage source and to each tripping device, the electric storage device being adapted to receive electric energy from the voltage source and to provide electric current to each tripping device to actuate the respective tripping device;

a control unit coupled to the acceleration sensor, the tripping devices, the voltage source, and the storage device, the control voltage source, and the storage device, the control unit receiving the output signals generated by the acceleration sensor and being adapted to control the flow of electric current to each respective tripping device in response thereto, the control unit being further adapted to determine if the storage device is defective, and, if so, to interrupt the flow of electric current from the storage device to the tripping devices, and to direct the electric current from the voltage source to a respective tripping device to actuate the tripping device; and

first means coupled to the control unit for permitting electric current to flow through each respective tripping device for a predetermined period of time to actuate the tripping device.

8. An apparatus as defined in claim 7, wherein

the voltage source is the vehicle battery;

the electric storage device is a capacitor; and

the first means includes a plurality of timing units, each timing unit being coupled to the control unit and to a respective tripping device t permit electric current to flow through the tripping device for predetermined period of time.

9. An apparatus as defined in claim 8, further comprising;

a plurality of switches, each switch being coupled to the control unit between a timing unit and a respective tripping device, each switch being actuated by the control unit for a predetermined period of time in response to the respective timing unit to permit electric current to flow through the respective tripping device.

10. An apparatus as defined in claim 8, further comprising:

a volt meter coupled to the capacitor and to the control unit, the volt meter generating output signals to the control unit indicative of the voltage across the capacitor, the control unit in turn determining if the capacitor is defective in response thereto.

11. An apparatus for actuating a passenger restraint device on a motor vehicle, comprising:

an acceleration sensor mounted on the motor vehicle for generating output signals indicative of the acceleration thereof;

a plurality of tripping devices, each tripping device being coupled to a respective passenger restraint device, each tripping device being actuated by the passage of electric current therethrough to actuate the respective passenger restraint device;

a voltage source coupled to each tripping device to provide electric current thereto to actuate the respective tripping device;

an electric storage device coupled to the voltage source and to each tripping device, the electric storage device being adapted to receive electric energy from the voltage source and to provide electric current to each tripping device to actuate the respective tripping device;

a control unit coupled to the acceleration sensor, the tripping devices, the voltage source, and the storage device, the control unit receiving the output signals generated by the acceleration sensor and being adapted to control the flow of electric current to each respective tripping device in response thereto, the control unit being further adapted to determine if the storage device is defective, and, if so, to interrupt the flow of electric current from the storage device to the tripping devices, and to direct the electric current from the voltage source to a respective tripping device to actuate the tripping device;

first means coupled to the control unit for permitting electric current to flow through each respective tripping device for a predetermined period of time to actuate the tripping device; and

second means coupled to the first means for measuring the ambient temperature of the storage device and generating output signals to the first means indicative thereof, the first means in turn basing the predetermined period of time thereon.

12. A method of actuating a passenger restraint apparatus on a motor vehicle, the apparatus including a plurality of tripping devices, each tripping device being coupled to a respective passenger restraint device, a voltage source, and a storage device, the storage device being coupled to the voltage source to receive electrical energy therefrom, each tripping device being actuated by passing electric current therethrough to in turn actuate the respective passenger restraint device, comprising the following steps:

checking if the storage device is defective;

if the storage device is defective, interrupting the flow of electric current from the storage device to the tripping devices; and

passing electric current from the voltage source to a respective tripping device for a predetermined period of time to actuate the tripping device and, in turn, actuate the respective passenger restraint device.

13. A method as defined in claim 12, wherein

the predetermined period of time is the same for each respective tripping device.

14. A method of actuating a passenger restraint apparatus on a motor vehicle, the apparatus including a plurality of tripping devices, each tripping device being coupled to a respective passenger restraint device, a voltage source, and a storage device, the storage device being coupled to the voltage source to receive electrical energy therefrom, each tripping device being actuated by passing electric current therethrough to in turn actuate the respective passenger restraint device, comprising the following steps:

checking if the storage device is defective;

if the storage device is defective, interrupting the flow of electric current from the storage device to the tripping devices;

passing electric current from the voltage source to a respective tripping device for a predetermined period of time to actuate the tripping device and, in turn, actuate the respective passenger restraint device;

measuring the ambient temperature of the storage device; and

selecting the predetermined period of time based thereon.

15. A method of actuating a passenger restraint apparatus on a motor vehicle, the apparatus including a plurality of tripping devices, each tripping device being coupled to a respective passenger restraint device, a voltage source, and a storage device, the storage device being coupled to the voltage source to receive electrical energy therefrom, each tripping device being actuated by passing electric current therethrough to in turn actuate the respective passenger restraint device, comprising the following steps:

checking if the storage device is defective;

if the storage device is defective, interrupting the flow of electric current from the storage device to the tripping devices; and

passing electric current from the voltage source to a respective tripping device for a predetermined period of time to actuate the tripping device and, in turn, actuate the respective passenger restraint device, wherein the predetermined period of time is varied depending upon the respective tripping device.

16. An apparatus for actuating a passenger restraint device on a motor vehicle, comprising:

a voltage unit;

an electrical storage unit coupled to the voltage unit to receive electrical energy therefrom;

a plurality of tripping devices, each tripping device being coupled to a respective passenger restraint device, the voltage unit and the electrical storage unit, each tripping device being actuated by the passage of electric current therethrough to, in turn, actuate the respective passenger restraint device;

first means coupled to the electrical storage unit for checking if it is defective and for generating signals indicative thereof; and

second means coupled to the first means for interrupting the flow of electric current from the electric storage device to the tripping devices in response to the signals generated by the first means, and for directing electric current from the voltage source to a respective tripping device for a predetermined period of time to actuate the tripping device and, in turn, actuate the respective passenger restraint device.

17. An apparatus as defined in claim 16, wherein

the second means includes a plurality of timing units, each timing unit being coupled between the first means and a respective tripping device to permit electric current to flow through the respective tripping device for a predetermined period of time.

18. An apparatus as defined in claim 17, wherein the second means further includes

a control unit coupled to each timing unit, and a plurality of switches, each switch being coupled to the control unit between a respective timing unit and a respective tripping device, the control unit being adapted to actuate the switches to control the flow of electric current to a respective tripping device.

19. An apparatus as defined in claim 18, wherein

the first means includes a volt meter coupled to the storage device and to the control unit, the volt meter transmitting signals to the control unit indicative of the voltage across the storage device, the control unit being adapted to compare the signals to a threshold value and, if the signals are below a threshold value, to interrupt the flow of electric current from the storage device to the tripping devices.