GB633066A - Improvements in or relating to machines for grinding wire-drawing dies - Google Patents

Abstract

633,066. Grinding wire - drawing dies. HALIFAX WIREDRAWING DIE CO., Ltd., and DAWTREY, F. April 30, 1946, No. 12957. [Class 60] A machine for grinding wire-drawirig dies, of the kind in which a revolving needle f is reciprocated within the orifice of a die, carried in a holder a, which die is itself revolving and is adjustable rotatably about a vertical axis c<SP>1</SP>, the surface of the needle being supplied with a suitable abrasive and being pressed by spring action against the wall of the die orifice, is characterised in that the part g carrying the reciprocating rotating grinding needle f is mounted slidably in a bracket or member h which is pivotal, at h<SP>1</SP>, about an axis parallel to or aligned with that of the die-holder a when the latter is in central position, a spring being provided at m, which tends to swing the needle holder in a direction to maintain the needle in yielding contact with the wall of the die orifice. The needle holder g is movable axially by means of a lever i bearing on a collar g<SP>1</SP> on the holder against the action of springs j. Means for indicating the attainment of grinding limits include two axially-movable contacts p, r arranged adjacent the bracket h and adapted to be engaged by a contact s on the bracket. The contact p, which is slidable within the contact r, is caused by a spring to project slightly beyond the inner end of the member r, so that an indication can be given just before grinding is complete. When the grinding is completed the machine may be automatically stopped. Alternative indicating means include a lever moved over a resistance, and a voltmeter with an indicating needle.