JPS56158202A - Manufacture of deformed rod - Google Patents

Abstract

PURPOSE:To exactly manufacture a deformed rod with a prescribed bisymmetrical section shape, by forming a wire rod having a round section into a bisymmetrical shape having a vertical angle, and by applying a rolling work to the vertex of this vertical angle. CONSTITUTION:A base metal made wire rod 4 having a round section is rolled by a roll-forming roll into a wire rod 4'' of an equilateral triangular section. The vertex C of the bilateral triangular section of the wire rod 4'' is then inserted into a projection-forming groove 7 of a roll-forming roll 8 on the lower side, and the wire rod 4'' is subjected to a roll-forming work performed by the lower roll-forming roll 8 and an upper rolling roll 6 provided with a forming groove 5. Hereby, a base rod 3, with a trapezoid section provided with a longitudinal projection 1 in the middle of a surface to be welded to a spring material, is obtained. By the present method, the vertexes C, D, E of the wire rod 4'' are respectively firmly held by the forming grooves 5, 7 during the roll-forming work, so that the wire rod 4'' does not incline and is exactly and easily formed into a deformed rod of a prescribed bisymmetrical section shape.