Straightening apparatus

Apparatus for straightening elongate material, the apparatus comprising a pair of rotary members arranged in series and drive means for counter-rotating the rotary members, each rotary member having a passage through which the material passes and guide means for guiding the material through the passage in the rotary member, the guide means including deflection means for deflecting the material away from the axis of rotation of the rotary member, wherein the deflection means is so shaped as to cause the path taken by the material to have a first, curved portion which is directed away from said axis, followed by a second portion, which is substantially parallel with the axis of rotation or is less tightly curved than the first portion, both portions being spaced from said axis of rotation, the deflection means comprising a sleeve positioned in the path of wire through the rotary member, the sleeve being rotatably mounted on the member so as to be rotatable relative to the member about an axis substantially parallel with the axis of rotation of the member, the apparatus further comprising feed means for feeding material through the rotary members at a variable rate and control means operable to control the drive means to cause the speed of rotation of the rotary members to be proportional to the rate at which wire is fed through them and wherein the feed means comprises a reciprocating clamp moveable through a succession of alternating advances and return strokes, and operable to grip the material during the advance strokes and to release the material during the return strokes.