Linear drive motor control system

A drive control device for use in a linear motor having a stator and a sliding member capable of sliding along said stator comprising:

• a tone arm assembly coupled to said sliding member;
• means for detecting the position of said sliding member relative to said stator and producing an electrical position signal representative of displacement of said member from a reference position on said stator, said detecting means comprising at least one of a predetermined one of a light emitting element and a light detecting element arranged on said sliding member and at least one of the other one of said light emitting element and light detecting element being provided at at least one stationary reference position, said position signal being produced at an output of said light detecting element;
• signal producing means for producing a reference electrical signal, a magnitude of said reference signal being an average of a maximum level and a minimum level of said position signalover all positions of said sliding member along said stator;
• means for comparing said position signal with said reference signal to produce an output signal;
• and
• means for controlling driving of said linear motor in response to said output signal to stop sliding movement of said sliding member when said reference signal exceeds said position signal.