Patent ID: 6469406
Filing Date: 2002-10-22
Classification: H02K

Abstract:
A linear motor including a stator having a plurality of spaced apart permanent magnets inside a stator back plate, the stator back plate having a bottom and side walls, and a rotor provided on one side of a frame and adapted to move along an inner side of the stator, the linear motor further comprising:a blower provided outside the linear motor; a plurality of supply pipes coupled by one end thereof to said blower and provided at predetermined locations externally of the stator, said supply pipes extending in proximity to the bottom and the side walls of the stator back plate along the travel trajectory of the rotor within the inner side of the stator; a plurality of air guide holes formed through the bottom and the side walls of the stator back plate at predetermined locations thereat, said air guide holes formed through said side walls being in alignment with the spaces defined between each pair of adjacent said permanent magnets, each of said air guide holes being coupled to a respective one of said supply pipes in fluid communication and in transversal relationship therewith for guiding flow of air into direct contact with heat generating structures of said linear motor; and a plurality of control valves provided at predetermined locations of said supply pipes, each said control valve being coupled between a respective one of said supply pipes and a respective one of said air guide holes and being selectively opened/closed according to a position of the rotor moving along the inner side of the stator for controlling an amount of an introduced air and an area of the air introduction into direct contact with the heat generating structures of said linear motor.