The collision sensor is a control signal input device in an airbag system. Its role is to detect the intensity signal of the car collision by the collision sensor when the car collides, and input the signal to the airbag computer. The airbag computer judges whether the inflation element is detonated to inflate the airbag according to the signal of the collision sensor.
Most collision sensors use an inertial mechanical switch structure, which is equivalent to a control switch. Its working state depends on the acceleration of the car during a collision. According to the structure, it can be divided into two types: mechanical and electronic. Mechanical types include rolling ball type, roller type, and eccentric ball type.
The collision sensor is used to detect and judge the collision signal when the car collides, so as to ignite the airbag in time.
Airbag SRS (Supplemental Restraint Systems) is a common passive safety device on automobiles. The function of the airbag is to form a cushion cushion between the driver and the steering wheel, and between the front seat occupant and the instrument panel, to avoid hard impact and injury. An airbag system generally consists of a collision sensor, an electronic control unit (ECU), an airbag module (including a gas generator, an airbag, an igniter), a monitoring device, and a reserve power source.
According to their functions, sensors can be divided into two types: collision signal sensors and collision protection sensors. The structural principle of the collision protection sensor and the collision signal sensor is basically the same, the difference is that the set deceleration threshold is different.
Generally, the collision sensor can be used as a collision signal sensor or a collision protection sensor, but its deceleration threshold must be set. The collision sensor is responsible for detecting the intensity of the collision; the purpose of setting the protection sensor is to prevent the accidental short-circuit of the front sensor and prevent accidental expansion, because when the front collision sensor is not set, if it is not monitored, The terminal of the signal output terminal makes the circuit of the igniter switch on, then the airbag will detonate and expand.
According to their structure, sensors can be divided into eccentric hammer type sensors, rolling ball type impact sensors, roller type expansion sensors, mercury switch type impact sensors, piezoresistive effect type impact sensors and piezoelectric effect type impact sensors.