Patent ID: 8143750

Claim:
A linear motor comprising a rod equipped with magnets, coils surrounding the rod, and a housing covering the coils, the rod being made to linearly move relative to the coils by magnetic fields from the magnets and current made to flow through the coils, wherein the rod has an outer circumferential surface on which a spline groove is formed so as to run along an axial direction of the rod, the housing has a revolution stopper that fits to the spline groove and limits the rod from revolving around an axis line thereof, the rod has a magnet shaft, on which the spline groove is not formed, the magnet shaft having a hollow space therein, in which the magnets are disposed, and the rod also including a spline shaft, connected to an end of the magnet shaft, and having the spline groove formed thereon, wherein the revolution stopper includes a spline nut that guides the spline shaft and the housing includes a bush that surrounds, directly supports the hollow space of the magnet shaft and guides the magnet shaft, and wherein the rod is supported at two support positions provided by the spline nut and the bush.