PARKING BRAKE SYSTEM, COMPUTER-IMPLEMENTED METHOD OF CONTROLLING A PARKING BRAKE SYSTEM OF A RAIL VEHICLE, COMPUTER PROGRAM AND NON-VOLATILE DATA CARRIER

A parking brake system for a rail vehicle (100) contains a brake actuator (120) for receiving a parking-brake command (cmdp) and producing an electric brake-force signal (BF). A brake unit (200) contains first and second pressing members (211, 212) and a rotatable member (110) being mechanically linked to a wheel (105) of the rail vehicle (100). When receiving the electric brake-force signal (BF), the brake unit (200) causes the first and second pressing members (211, 212) to apply a braking force to the rotatable member (110) to keep the wheel (105) immobile. A gear assembly (220) in the brake unit (200) operates mechanically on the first and second pressing members (211; 212). In response to the electric brake-force signal (BF), an electric motor (230) acts on the gear assembly (220) to cause the first and second pressing members (211; 212) to attain a specified position interrelationship. An acceleration sensor (125) registers movements of the rail vehicle (100). If movements of the rail vehicle (100) above a magnitude threshold level are registered during a period when the parking-brake command (cmdP) has instructed the at least one wheel (105) to be immobile, the brake actuator (120) reproduces the electric brake-force signal (BF) to reapply the braking force to the rotatable member (110).