Infrared axle temperature detection equipment consists of probe, axle temperature information processing device, transmission line and signal alarm device. ① Probe: It consists of photosensitive device and photoelectric conversion device, and is installed on the cement foundation beside the railway rail outside the station warning signal. Its function is to collect the infrared radiation energy of the axle box through photosensitive devices and convert it into electrical signals through photoelectric converters for output. The intensity of the electrical signal is directly proportional to the infrared radiation energy of the axle box. ② Shaft temperature information processing device: a signal processing system consisting of electron tubes or transistors, integrated circuits or microcomputers, which shapes, amplifies and processes the electrical signals transmitted by the probe. (3) Transmission line: use special cable, microwave circuit or multi-channel carrier equipment to transmit the electrical signal processed by axle temperature information to the signal alarm or display center. The transmission system adopts frequency modulation, and the frequency is generally selected within the audio range. ④ Signal alarm device: a device that receives the electric signal of shaft temperature information, and automatically sends out visual or auditory signals when the important official temperature exceeds a specified difference or a certain proportion. Alarm methods include limit method, coaxial comparison method and ipsilateral comparison method. The limit method is to give an alarm when the important official temperature exceeds a certain limit value. Coaxial comparison method includes axial difference method and axial ratio method. Axle difference refers to the temperature difference between two bearings of the same axle, and axle ratio refers to the temperature ratio between two bearings of the same axle. When the difference or ratio exceeds a certain value, an alarm will be given. The same side comparison method is to compare the temperatures of bearings on the same side of a car or train, and alarm when it exceeds a certain limit.

The results of axle temperature detection are represented by pen recorder, digital display and track display board, which can directly determine the position of hot axle in trains and vehicles.