Patent ID: 6703725
Filing Date: 2004-03-09
Classification: H02K

Abstract:
A joint driving apparatus for generating a relative movement between first and second members on a joint, comprising:a linear motor including: at least one stator part fixed to the other one of the first and second members, a movable element movable with respect to the stator part in a movable direction and connected to the one of the first and second members to be moved with respect to the other one of the first and second members, and an electromagnetic coil device for energizing the stator part to be magnetized so that a magnetic field for urging the movable element in the movable direction with respect to the stator part is generated; wherein the stator part includes at least two pairs of magnetic poles, the at least two pairs are adjacent to each other in the movable direction and magnetized simultaneously with the identical common magnetizing phase by the electromagnetic coil device, the magnetic poles of each of the at least two pairs face to each other through the movable element in a movable element thickness direction perpendicular to the movable direction to generate the magnetic field passing the magnetic poles through the movable element in the movable element thickness direction, and a magnetic polar direction of one of the at least two pairs is opposite to that of the other one of the at least two pairs adjacent to the one of the at least two pairs in the movable direction when the stator part is magnetized.