| 摘要 |
PURPOSE:To dispense with a slide bed having a high accuracy guide surface by providing a piston on a portion of a spindle and supplying working fluid from a fluid supply port provided in a housing to either front or rear portion of the piston to move directly the spindle forward and backward. CONSTITUTION:A work-piece 31 has a center hole 32 inserted into which a tapered portion 14 of a spindle 11 advanced when working fluid is supplied to a cylinder chamber 22 and a piston 12 is moved left. The working fluid is supplied by an amount compensating for the leakage from a clearance between a cylinder portion 13 and the piston 12. Also the press force of a tail spindle is adjusted such that differential pressure between cylinder chambers 21, 22 is maintained always at a certain pressure by a pressure regulating value of a working fluid device. When a spindle bed is rotated, the spindle 11 is also rotated, and when the working fluid is supplied into the cylinder chamber 21 after working the work-piece 31, the spindle 11 retreats to be diengaged from the work-piece. That is, the spindle is moved directly forward and backward to dispense with a slide bed. |
