Supervising device for monitoring the operation of an anti-slip device of a railway braking system

Supervising device for monitoring the operation of an anti-slip device of a railway braking system;

• said anti-slip device being arranged to:
• receiving instantaneous speed signals of at least two axles;
• controlling pressures to brake cylinders associated with said axles by means of electro-valve units;
• preventing blockage of the axles and controlling the slipping of said axles by controlling the pressures to the brake cylinders associated with said axles by means of said electro-valve units;
• said electro-valve units each comprising two pneumatic solenoid valves;
• each pneumatic solenoid valve being provided with a timing device arranged to measure a supply time of the respective pneumatic solenoid valve and each to generate a signal arranged to de-energize said respective pneumatic solenoid valve if the measured supply time of the respective pneumatic solenoid valve exceeds a predetermined preloaded time value;
• the supervising device being arranged to:
• acquiring estimated instantaneous linear speeds associated with the axles controlled by said anti-slip device;
• comparing said estimated instantaneous linear speeds associated with axles with a linear reference speed of the railway vehicle;
• monitoring the state of the pressures to the brake cylinders;
• determining, for each axle in a slipping phase, whether said anti-slip device is working correctly or if it is not working correctly, depending on predetermined operating conditions including predetermined trends of each of the estimated instantaneous linear speeds associated with the axles in the slipping phase, with respect to the reference linear speed of the railway vehicle, in association with each of the pressures to the brake cylinders associated with the axles;
• maintaining, reducing or canceling the preloaded time value in at least one of the timing devices associated with the axles in the slipping phase, during the execution of counting of said pre-loaded times by said timing devices, when the supervising device determines that the anti-slip device is not working correctly.