VERTICAL LATHE, TOOL HEAD FOR VERTICAL LATHE, ROTARY TABLE DEVICE FOR MACHINE TOOL

摘要

PURPOSE: A vertical lathe, a tool head for the vertical lathe, and a rotary table device for a machine tool are provided to easily perform turning operations of workpieces which need the variation of tool angle as producing a fresnel lens mold. CONSTITUTION: In a vertical lathe of an open side column type, a pair of linear guides are arranged in parallel in a cross rail(62), and a hollow part is formed between the linear guides. A saddle(90) is supported by the linear guides above the hollow part and moved in an axial direction. A ram(120) is suspended through the hollow part and moved in a vertical direction. A rotary driving disc fixed on a table rotation driving shaft is connected to a rotary table(30) by plural torque transmission pins in a torque transmission relationship. Accordingly, the rotary table rotates in a carrier method. A tool holder(151) is rotatably driven at an optional angle position by a B axis servomotor(163) for a horizontal axis. In addition, the tool holder is clamped at an optional rotation angle position by a thrust static pressure bearing under oil-pressure supply to one of thrust static pressure portions. The tool angle is changeable by using the B axis servomotor.