GB660112A - Improvements in or relating to machine tools - Google Patents

Abstract

660,112. Copying by turning etc.; coiling. BAILEY METER CO. Dec. 12, 1947 [Oct. 29, 1945], No. 32829/47. Classes 83 (iii) and 83 (iv). [Also in Group XXIX] In a lathe, Fig. 1, the arm 24 of a tracer assembly 16 traverses a templet 17 as the tool 10 traverses a rotatable workpiece 11, the tool being movable at a uniform speed parallel to the axis of the workpiece by means of a lead screw 12 and being movable at a controllable speed towards or away from the workpiece at an angle, preferably 45 degrees, to the axis thereof by means of a hydraulically-operated. servomotor 13 which is adapted to be secured to the tool rest 9 so as to be angularly positionable therewith, the tracer assembly being carried by an arm 18 adjustably and pivotally connected to the tool rest so that the tracer arm is movable as a result of variations in the contour of the templet to effect actuation of a power regulator which controls the supply of fluid to the servomotor. The tracer arm is operatively connected to a valve member forming part of the tracer assembly and through which air under constant pressure bleeds to atmosphere. Movement of the tracer arm effects movement of the valve member to vary the bleed to atmosphere, such variations in the air bleed acting upon a bellows of a pilot valve assembly 23 for controlling the supply of fluid to the servomotor. The templet is adjustable according to the type of out desired. In a vertical turning and boring mill, Fig. 4, the workpiece 36 is mounted on a rotatable holder 35, the templet 38 is mounted on a verticallyadjustable saddle 39, and the servomotor 13 is angularly movable on a head 41 movable along cross rails 42 of the saddle 39. The direction of rotation of the workpiece is reversed as the tool 37 passes through the axis of rotation of the workpiece. The invention is stated to be applicable to other machine tools, e.g. milling machines, slotters, planers, and diesinking machines. Specification 600,193 and U.S.A. Specification 2,436,373 are referred to. Coiling.-For coiling springs of varying pitch, the tool is replaced by a guide through which the wire is passed, the guide moving along a rotating mandrel, on which the spring is coiled, as the tracer arm traverses the templet.