Knock Sensor


The knock sensors have the function to provide better performance and economy of the engines. In the Otto cycle, these sensors allow the ignition point to operate as close as possible to the ideal. In the Diesel cycle, sensors are closer to the knock limits.

This type of sensor is made up of a metallic mass and a piezoelectric ceramic which when vibrating, generates an electrical signal. NTK has two types of knock sensors:

– KN type Sensors. These sensors, non-resonant, have wide operation range between 5 and 15 kHz. They can be applied in several types of engines and their knock frequency is determined during the calibration of the engine.

– KR type Sensors. They are resonant sensors with signal generated at a specific operation frequency. Due to this characteristic, the KR type sensors are developed specifically for each type of engine.

The knock sensors have a specific torque. The torque change can affect the signal generated by the sensor. NTK recommends torque of 2.0 to 2.5 kgf.m and does not recommend the use of grease or washers on mounting the knock sensor.