Patent ID: 8752281
Filing Date: 2014-06-17
Classification: B23B,B23Q,E05B,Y10T

Abstract:
1. An actuator system comprising: a spindle member extending along an axis, nonrotatable about the axis, and shiftable axially; a chuck having a part engageable by the spindle and axially shiftable thereby to grip a tool or workpiece; a drive having an output member rotatable about the axis; a nut threaded to one of the members; a spring braced axially between the other of the members and the nut such that the nut and other member can move axially relative to each other when a predetermined spring force is exceeded; first sensor means for monitoring longitudinal movement of the nut relative to the other member and for producing an output corresponding thereto; second sensor means for monitoring longitudinal movement of the spindle member and for producing an output corresponding thereto; and is control means for comparing the outputs and operating the drive in accordance a difference therebetween.