ANTRIEBSGETRIEBE FUER MASCHINEN.

摘要

A drive mechanism for a machine such as a machine tool or robot includes a rotatable shaft, e.g. a lead screw or spindle, drivingly connected with a movable element, e.g. a worktable or tool support, in the machine, a drive shaft for rotation by a motor and a coupling unit, e.g. clutch or gear transmission, for drivingly connecting the drive shaft with the rotatable shaft to move the movable element in a predetermined form of movement under a variable load in the machine. Encoders are provided in a rotation-sensing relationship with the drive shaft and the rotatable shaft, respectively, to feed two trains of rotation-responsive pulses into a differential counter which provides a difference in angle of rotation signal representing an instantaneous torque produced at the drive coupling unit between the drive and rotatable shafts. The differential signal and a preset signal set in a setting circuit, representing a predetermined value of torque are processed in an output circuit which produces a control signal which is used to control the motor or the coupling unit so as to maintain the torque between the drive and rotatable shafts substantially at the reference value.