Torque Sensor Knowledge Dry Goods Sharing

In life, I think everyone has encountered such problems. The torque sensor is faulty. Once the torque sensor fails, it will bring a lot of trouble. If it is serious, there will be a traffic accident! So be careful. Found that this torque sensor is broken, to be repaired in time.

Torque sensors are typically used to measure the magnitude and direction of the torque applied by the driver on the steering wheel and convert it into an electrical signal. The power is converted to the ECU, which receives this signal and the speed signal, and determines the direction and magnitude of the auxiliary power. Therefore, the controlling torque becomes smaller when driving at low speed and moderately larger when driving at high speed, which is one of the important components of the electronically controlled power rotation system.

At present, the C-moment sensor can be divided into two kinds: contact and non-contact. Non-contact torque sensors are also known as sliding variable resistance torque sensors. Contact torque sensors install a torsion bar between the steering shaft and the steering pinion, use slip rings and potentiometers to measure the deformation of the torsion bar when the steering system is working, and convert it into a voltage signal. The non-contact torque sensor has two pairs of polar rings. If the relative rotation between the input shaft and the output shaft occurs, the air spacing between the polar rings will change, the electromagnetic induction coefficient will change, the coil will generate an induced voltage, converting the voltage signal into a torque signal, and the advantages of non-contact torque sensors are small size and high precision.

In addition, some sensors can also measure the size and direction of the steering wheel Angle. Torque measurement is a complex system, high cost, such as Toyota vehicles on the steering motor, torque sensor and steering column integrated into the steering column assembly, so that steering control is more reliable.

Generally speaking, when the torque sensor is damaged or poor performance, the steering system may experience the following types of failures:

1. Difficulty in turning; The left and right rotating torques are different or the rotating torques are uneven.

2, when driving, the torque will not change with the speed, or the steering wheel can not rotate normally.

3, the P/S warning light on the instrument is turned on.

There are many reasons why the process signal of torque sensor is unstable. Generally speaking, there are three aspects: First, the torque sensor is not installed well, the shaft is not parallel, which will lead to unstable signal output, and the sensor is easily damaged in such a state for a long time. Second, the electrical voltage is unstable. The torque sensor is generally positive or negative 15V dual-voltage power supply is also powered by 24V or other voltages, and the instability of the power supply voltage will cause the output signal to be unstable.

The third reason is also easy to overlook. This is interference from other machines next to the torque sensor. For example, there is a frequency converter next to the torque sensor, and the output signal is easy to be unstable. The solution is to add a 1:1 isolation switch in front of the sensor's power supply.