Multi-pitch screw, multi-pitch nut, feed screw device using the screw and nut, and method of producing the nut
AssigneesKabushiki Kaisha Imasen Denki Seisakusho, Nagoya Industrial Science Research Institute
InventorsHiroshi Fujii, Katsuhiro Sugiyama, Masashi Mitsukuchi, Kenichi Katayama, Yoshinori Moriguchi
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Abstract
A flat portion 12a and a slope portion 12b are provided on a thread 12 of a multi-pitch screw 10 alternately. The flat portion and the slope portion are provided on the thread of a multi-pitch nut which fastens with this. Consequently, a screw and a nut capable of preventing loosening securely by step are achieved. This enables comfortable and quick feeding and when a torque from a driving source is interrupted, step-like self-lock is activated.
Claims7
A combination of a multi-pitch screw and a multi-pitch nut, said multi-pitch screw comprising a thread of a male screw having both sides of the thread formed such that sections having a mild lead angle and sections having a steep lead angle are arranged alternately, continuously and stepwisely during a single turn along a spiral line, said multi-pitch nut comprising a thread of a female screw having both sides of the thread formed such that a section in which a lead angle is mild and a section in which a lead angle is steep are arranged alternately, continuously and stepwisely during a single turn along the spiral line.
Dependencies are inferred from the claim text.