Patent ID: 6703730
Filing Date: 2004-03-09
Classification: H02K

Abstract:
An electric motor comprising:an armature including a rotatable shaft; a cooling fan secured to the rotatable shaft of the armature to rotate integrally with the rotatable shaft; a yoke receiving the armature and the cooling fan and having at least one air inlet opening and at least one air outlet opening, wherein the at least one air inlet opening is located at a first axial end portion of the yoke and penetrates through a wall of the yoke to introduce air into an interior of the yoke upon rotation of the cooling fan, and the at least one air outlet opening is located at a second axial end portion of the yoke and penetrates through the wall of the yoke to discharge the air from the interior of the yoke upon the rotation of the cooling fan; and a water blocking cover substantially blocking intrusion of water into the interior of the yoke by substantially covering the at least one air inlet opening and the at least one air outlet opening of the yoke, wherein the water blocking cover includes: an intake duct, through said intake duct the air is drawn from outside of the water blocking cover into the at least one air inlet opening upon the rotation of the cooling fan; an exhaust duct, through said exhaust duct the air is discharged from the at least one air outlet opening to the outside of the water blocking cover upon the rotation of the cooling fan; and a communication restraining portion being located in a space between the water blocking cover and the yoke and restrains free communication of the air between the intake duct and the exhaust duct through the space between the water blocking cover and the yoke.