Patent ID: 6365994
Filing Date: 2002-04-02
Classification: F02D,F02M

Abstract:
A motor comprising:a motor case for an armature of said motor, a rotor shaft reciprocating with rotating motion of said motor, a rotor unit of said motor having a magnet, a single ball bearing, and a magnet holder for supporting said magnet and an inner race of said ball bearing, wherein an outer race of said single ball bearing inserting a socket portion of said motor case, and a plane bearing for supporting one end of said rotor, another end at which said ball bearing is fixed and controlling movement in a thrust direction wherein a small gap exists between an upper axial end of said outer race of said single ball bearing and an axial end face of said socket portion of said motor case, said small gap being equal to or smaller than an amount of relative movement between said inner and outer races of said single ball bearing in a thrust direction , further wherein said small gap existing in a static state does not exist when said outer race of said ball bearing is pressed to said motor, and said rotor displaces in the thrust direction in the same amount as a relative displacement between said outer race and said inner race of said single ball bearing in the thrust direction before said outer race of said ball bearing is pressed to said motor, and said displacement of said rotor in the thrust direction becomes smaller than the relative displacement between said outer race and said inner race of said single ball bearing in the thrust direction after said outer race of said ball bearing is pressed to said motor.