Abstract: Based on respective output signals (S4, S5, S7, S8) satellite sensors (4, 5) provided in an impact zone of a front section of a vehicle (1); an X-direction sensor (7) that detects an impact acceleration of the vehicle in a traveling direction thereof; a Y-direction sensor (8) that detects an impact acceleration in a direction that is orthogonal to the traveling direction, a control unit (6) that controls the operation of an air bag device (2) includes: a selection output portion that fetches, from among output signals (S40, S50) from the satellite sensors (4, 5) and an output signal (S80) from the Y-direction sensor (8), the output signal with the higher value; and a determination portion (9) that performs a collision determination of the vehicle (1) in response to the output signal (S7) from the X-direction sensor (7). A level of a threshold value used for the collision determination performed by the determination portion (9) is set based on the output signal selected by the selection output portion.

Abstract: A control apparatus of an occupant protection device has at least one front acceleration sensor provided in a front part of a vehicle, in addition to a room acceleration sensor provided in a room of the vehicle. Whether the vehicle is in a collision requiring a drive of the occupant protection device is decided based on each of sensor outputs of the room and front acceleration sensors, respectively, and the occupant protection device is driven when the collision is detected based on at least one of the sensor outputs. Since the front acceleration sensor is provided in the front part of the vehicle, the front acceleration sensor detects a collision acceleration early and gives it to the control unit, even in case of a collision, such as the offset or an oblique collision, in which a collision acceleration transmitted to the room acceleration sensor may be weakened. Therefore, the control unit can exactly drive the occupant protection device without causing delay in collision detection.

Abstract: A control apparatus of an occupant protection device has at least one front acceleration sensor provided in a front part of a vehicle in addition to a room acceleration sensor provided in a room of the vehicle. The front acceleration sensor detects an acceleration of the vehicle and gives the control unit a sensor output representative thereof. The control unit, when the sensor output of the front acceleration sensor is a sensor output caused by a collision of the vehicle, detects a variational quantity of the sensor output of the front acceleration sensor based on sensor outputs of the front acceleration sensor at two different time points, and increases an integrated value of an acceleration signal of the room acceleration sensor based on the variational quantity. Then, when the integrated value of the room acceleration sensor exceeds a threshold value, the occupant protection device is driven.

Abstract: A control apparatus of an occupant protection device detects whether a vehicle is in a collision requiring to drive the occupant protection device based on at least one front acceleration sensor provided in a front part of the vehicle, in addition to a collision detection based on a room acceleration sensor provided in a room of the vehicle. When the collision is detected based on the front acceleration sensor, an integrated value of an acceleration signal of the room acceleration sensor is increased. Since the front acceleration sensor is provided in the front part of the vehicle, the front acceleration sensor detects a collision acceleration early and gives a sensor output to the control unit, even in case of a collision in which a collision acceleration transmitted to the room acceleration sensor may be weakened.

Abstract: A control apparatus of an occupant protection device, in addition to a room acceleration sensor provided in a room of a vehicle, has at least one front acceleration sensor provided in a front part of the vehicle. The front acceleration sensor, when detecting a predetermined collision acceleration, gives a detection signal to a control unit. The control unit sets a second threshold value lower than a first threshold value if the detection signal is input, and drives the occupant protection device when an integrated value of an acceleration signal of the room acceleration sensor exceeds the second threshold value. Since the front acceleration sensor is provided in the front part of the vehicle, even when a collision acceleration transmitted to the room acceleration sensor is weakened, the front acceleration sensor detects the collision acceleration early and gives the detection signal to the control unit.

Abstract: If an impact acceleration Gt in excess of a predetermined value is detected (step 102), a speed integral value &Dgr;V is calculated (step 110) and a length of a line segment of the impact acceleration with a passage of time is calculated (steps 112, 114). If a rate of an increment of the speed integral value &Dgr;V to the length of the line segment within a predetermined interval is smaller than a predetermined value R, it is decided that resonance is caused. Then, it is decided (step 122) whether or not the speed integral value &Dgr;Vt exceeds a new threshold value which is set on the more negative side from a threshold value &Dgr;VTH which is defined by V(G), by a predetermined value &agr; (step 120). If it is decided that the speed integral value &Dgr;Vt exceeds the new threshold value, an inflation of an air bag is carried out (step 124).

Abstract: A start control system for a passenger protection system wherein after a first inflator has been fired, a detected deceleration of the vehicle is compared with a previously stored predetermined deceleration. Next, time integration is executed over an area in which the detected deceleration of the vehicle exceeds the previously stored predetermined deceleration if it has been decided that the detected deceleration of the vehicle exceeds the previously stored predetermined deceleration to increase speed reduction. Then, the time integral value is added to a speed integral value which is calculated as time integration of the detected deceleration of the vehicle until a point of time when it has been decided that the detected deceleration of the vehicle exceeds the previously stored predetermined deceleration. Finally, a start signal for a second inflator is output by a CPU to fire the second inflator when an added result exceeds a predetermined threshold value.