Preventive function control in an electromagnetic spring pressure brake

Abstract

The invention relates to a method for preventive function control in an electromagnetic spring pressure brake for a simpler and more accurate determination of the critical operating state. The spring pressure brake comprises at least one coil, and an armature disk, a coil carrier having compression springs distributed thereon, a control module, and a monitoring module having at least one semiconductor component, a current measuring device, and a voltage measuring device, wherein the method comprises the following steps: Initially, the spring pressure brake is controlled by the control module by means of a voltage. Next, the state variables current (I) and voltage (U) at the electromagnetic spring pressure brake are measured by the monitoring module. Subsequently, a determination variable (T; F) of the electromagnetic spring pressure brake is determined by the monitoring module. Said determination variable (T; F) is summed over a range (a), which extends from the starting point of the actuation to a point (W), at which the armature disk begins to move. At the point (W), a current value is detected, at which the movement of the armature disk begins. The determination variable (T; F) is additionally summed over a range (b), which extends from the point of actuation, when the current (I) again reaches the value detected above, up to the point, at which a constant current is reached. Subsequently, a ratio (X) is calculated from the sum of the determination variable over the range (a) to the sum of the determination variable over the ranges (a) and (b). Upon reaching or exceeding a predetermined value (Y) by the value of the ratio (X), a state signal relating to the spring pressure brake is output.

Dependencies are inferred from the claim text.