Patent ID: 6219895
Filing Date: 2001-04-24
Classification: B23Q,G05B,Y02P,Y10T

Abstract:
In a machine tool of the type wherein lengths of bar stock are rotated about longitudinal axes and machining tools are actuated by cams to engage the machining tools with the rotating bar stock to effect machining thereof, the improvement comprising:a plurality of working spindles each for receiving a length of bar stock therein and each defining an axis of rotation of its respective length of bar stock;a variable frequency spindle drive motor;a gear train operatively connecting the variable speed spindle drive motor to the working spindles to effect rotation of the working spindles and the lengths of bar stock carried thereby about the axes of rotation defined by the working spindles;a first cam shaft extending parallel to the axes of rotation defined by the working spindles;a plurality of first cams mounted on the first cam shaft for rotation thereby to cause operation of first machining tools thereby machining the lengths of bar stock carried by the working spindles during rotation thereof under the action of the variable frequency spindle drive motor;an indexing mechanism driven by the first cam shaft for sequentially indexing each of the working spindles through a plurality of workstations;a second cam shaft extending perpendicularly to the axes of rotation defined by the working spindles;a plurality of second cams mounted on the second cam shaft for rotation thereby to cause operation of second machining apparatus thereby machining the lengths of bar stock carried by the working spindles during rotation thereof under the action of the variable frequency spindle drive motor;a servomotor;a gear train operatively connecting the servomotor to the first and second cam shafts to effect rotation of the first and second cams and to effect operation of the indexing mechanism independently of the operation of the variable frequency spindle drive motor; anda programmable logic controller for controlling the operation of the variable frequency spindle drive motor and the servomotor.