Position detector with non-volatile storage for storing position data upon failure of supply voltage

摘要

A position detector with data evaluation circuit has at least one sensor which, in dependence on movement by which the position to be monitored alters, supplies electrical output signals to a circuit arrangement which produces there from a digital signal and puts it into intermediate storage until it is transferred to an evaluation unit. The digital signal reproduces in encoded form the position to be monitored. An energy converter converts a part of the kinetic energy of the movement into electrical energy and an energy storage means stores the electrical energy and provides same for supply to the circuit arrangement. A monitoring circuit outputs a control signal in response to a threatening drop in the supply voltage below a critical limit value. When the control signal occurs the digital signal is written into a non-volatile information storage means, in order thereby to make the position detector independent of an external power supply.