| 摘要 |
PURPOSE:To prevent a loss of waste of time in drawing cuttings by a method wherein a retreating motion of a piston rod is restrained by an one-direction clutch until the foremost advanced position of a main spindle is detected and the drawing of cuttings is controlled stepwisely in a returning direction of the main spindle. CONSTITUTION:Reciprocating motion in an axial direction of a quick feed and a quick return of a main spindle 14 is effected by an air cylinder 9 and a conversion from the quick feed to a cutting feed is controlled by engaging the main spindle 14 directly with a piston rod 22, a part of which is fitted within a cylinder chamber 11 and which is moved into an advancing direction with a speed following an oil discharging capacity of a flow regulating valve. A spring 23, causing a returning motion quickly, is functioning to this piston rod 22, however, a retreating returning motion is restrained by an one-direction clutch 71 until a foremost advanced position of the main spindle 14 is detected. By this restraint, the drawing of cuttings is controlled stepwisely to avoid a duplication and a loss of waste of time for the cutting feed may be prevented. |
