CNC controlled rotating work piece holding fixtures for a horizontal mill

摘要

A CNC controlled rotating workpiece holding fixture is attached to a tombstone of a horizontal mill. The rotating workpiece holding fixture(s) allows workpieces to be independently rotated to allow milling of various surface of the workpiece thereby providing a five axis CNC capability. As many as eight rotating workpiece holding fixtures may be attached to a single tombstone. Each rotating workpiece holding fixture may be formed by a harmonic drive driven by a servo motor which provides a compact configuration and a very low gear ratio in the harmonic drive combined with the inherent braking of the servo motor provides stability. The rotating workpiece holding fixtures may be controlled using existing auxiliary outputs (e.g., M-Codes), present in CNC milling machines. The M-Codes are preferably created by an operator, multiplexed, sent to the tombstone, de-multiplexed, and used to control each rotating workpiece holding fixture.

主权项

1. A CNC controlled horizontal mill and rotating workpiece holder comprising:
a tombstone attached to the horizontal mill; at least one CNC controlled rotating workpiece holding fixture mounted to the tombstone; a CNC controller generating rotating workpiece holding fixture commands for each rotating workpiece holding fixture; an M-code relay receiving activation signals from the CNC controller and forwarding the activation signals to a control box; a CNC position command for each rotating workpiece holding fixture generated by the CNC controller and provided to the control box; multiplexed position commands generated by the control box and provided to the tombstone after receiving the activation signal; a controller residing in the tombstone and receiving the multiplexed position commands and de-multiplexing the position commands to obtain individual rotating workpiece holding fixtures commands; communication between the controller and the rotating workpiece holding fixture providing signals to the rotating workpiece holding fixtures and providing rotating workpiece holding fixture position information back to the controller; communications from the controller to the control box providing a first motion finished signal to the control box; communication between the control box and the M-code relay providing a second motion finished signal to the M-code relay; and communication between the M-code relay and the CNC controller providing a third motion finished signal to the CNC controller.