A DEVELOPMENT OF A POPPET TYPE BRAKE PRESSURE CONTROL VALVE FOR A FRICTION BRAKE OF ROLLING STOCK

摘要

A poppet type brake pressure control valve, which the output pressure is proportional to the input displacement, is developed to use in the hydraulic control system for friction brake of railway rolling stock. Internal feedback structure is designed to eliminate the reliability problem of the pressure transducer, and the poppet type valve is utilized to reduce the internal leakage, which is a problem of the conventional control valve when the electrical supply is under failure. Compensation methods for the disadvantages of poppet valve and the stability are considered together with the structure of the valve. Static and linearized dynamic models of the valve are determined to study the effects and to decide the parameters of valve. The stability and performance of valve are studied and confirmed experimentally. The experimental results show that the response of output pressure is improved compared with the conventional pneumatic brake system.