A New Measurement Method and Apparatus for Measuring Duty Cycle of Air Brake compressor

摘要

The duty cycle of air brake compressor is one key factor to represent its power consumption and service life. In order to solve the duty cycle measurement problem for compressor of air brake system, a new measurement method is proposed and one duty cycle measurement apparatus (DCMA) is invented in this paper. The pressure value of air reservoir determines whether the high pressure air from air dryer discharges into the atmosphere or enters the air reservoir. A digital flow sensor is installed on vent port of air dryer to convert the air flow signal to the sampling signal input. DCMA triggers two accumulation timer circuits to obtain the total running time and ineffective working time of air brake compressor. Duty cycle can be indirectly measured by these two times. Duty cycles under different average speeds of one vehicle are measured by this measurement method and test apparatus. The results show that the duty cycles of this air brake compressor decrease with the average speed increasing, and test values exceed the limit value of 30% when the average speed is less than 44km/h. So the air displacement of this vehicle compressor should be increased. This measurement method is verified feasible through this vehicle test, and the convenience and effectiveness of DCMA are also confirmed.