SPANNER MANUFACTURING METHOD AND BENDING DEVICE Russian patent published in 2012 - IPC B21D7/02 B21K5/16 

FIELD: metallurgy.

SUBSTANCE: invention refers to metal pressure shaping and can be used for manufacture of curved rod items with inner polygon like a spanner. Shaping of spanner is performed on four shape-generating positions. On the first position there performed is the first preliminary compression of cylindrical head with simultaneous reduction of half the rod length. On the second position there performed is the second preliminary compression of head and final reduction of the rod. On the third position there performed is final compression of cylindrical head so that external conical part and internal polygon is formed with formation of a chamfer on the rod. On the fourth position there performed is workpiece bending. Besides, device includes matrix and clamp for workpiece. In addition, device is equipped with puncheon with pusher rigidly fixed on its end and swivel lever. Puncheon housing is provided with a hole in which floating workpiece clamp due to spring is installed. Swivel lever is installed on the axis perpendicular to longitudinal axis of matrix at the distance providing its rotation and workpiece bending at action of pusher on it.

EFFECT: higher quality of the item; lower metal consumption and labour intensity.

2 cl, 3 dwg