Patent ID: 7768159

Claim:
A linear motor comprising: a magnet member composed of permanent magnets having respective N poles and S poles alternately arranged in a predetermined axial direction, wherein said predetermined axial direction is a vertical direction, a coil member which is located orthogonally to said axial direction with respect to the magnet member and through which said magnet member is movable in the axial direction relative to the coil member, wherein said coil member surrounds the magnet member in a circular fashion, a magnetic substance located in the vicinity of one end of the coil member allows the magnet member to exert a magnetic attractive force, wherein said magnetic substance prevents the magnet member from falling down, wherein when said coil member is energized, none of the permanent magnets in the magnetic member move completely past the magnetic substance, wherein said magnet member is a movable-side member, whereas said coil member is a static-side member, said magnetic substance is located in the vicinity of an upper end of the coil member to inhibit said magnet member from falling down, and wherein said magnetic substance is installed at a height such that with the magnet member moved to a top dead center with respect to said coil member, the center of the vertical width of the magnetic substance is positioned in the vicinity of a center position of the vertical width between any magnetic poles of the N and the S poles alternately arranged in the magnet member.