Patent ID: 8727075

Claim:
Arrangement for supervising the operation of a brake, which arrangement comprises a controllable electromechanical brake, comprising a magnetic circuit, which comprises at least two ferromagnetic parts fitted to move in relation to each other, between which ferromagnetic parts a thrusting force is exerted via a spring or corresponding and which brake comprises a magnetizing coil fitted into the magnetic circuit, for forming magnetic attraction between the aforementioned parts of the brake, and which arrangement comprises a control of the brake, which comprises at least one controllable switch, for adjusting the electricity supply of the magnetizing coil, wherein the aforementioned control of the brake comprises a supervision of the movement of the magnetic circuit of the brake, which supervision of movement is fitted: to supply an electrical excitation signal to the magnetizing coil; to determine the electrical response signal corresponding to the aforementioned electrical excitation signal; to determine the inductance of the magnetic circuit of the brake from the aforementioned electrical excitation signal and electrical response signal; to determine the opening of the brake, when the inductance of the magnetic circuit of the brake increases within a defined time from an opening procedure of the brake at least to the extent of the minimum change in inductance required at that time, time; to determine the closing of the brake, when the inductance of the magnetic circuit of the brake decreases within a defined time from a closing procedure of the brake at least to the extent of the minimum change in inductance required at that time; and to determine an operating malfunction of the brake if the change in the inductance of the magnetic circuit of the brake remains after a brake control procedure at least for a defined period of time smaller than the minimum change in inductance required at that time.