Small size electric motor and manufacture thereof


Application Number: 00104915
Application Date: 2000.03.30
Publication Number: 1270435
Publication Date: 2000.10.18
Priority Information: 1999/3/30 JP 87822/99
International: H02K5/16;H02K15/14
Applicant(s) Name: Mabuchi Motor Co., Ltd.
Address:
Inventor(s) Name: Koya Kenji;Yuhi Shunya
Patent Agency Code: 72001
Patent Agent: zhang tianan
Abstract A bearing 4 is accommodated within a cylindrical bearing support portion 2. The bearing 4 has an outer diameter smaller than the inner diameter of the bearing support portion 2 such that a clearance is formed between the bearing 4 and the bearing support portion 2. At an approximate center of the bearing 4 with respect to the thrust direction, a projection 19 is continuously or non-continuously formed on the inner circumferential surface of the bearing support portion 2 along a circular line centered on the motor shaft. Further, a depression 20 corresponding to the projection 19 is continuously or non-continuously formed on the outer circumferential surface of the bearing 4 along the circular line. Thus, the bearing 4 is supported within the bearing support portion 2 in such a manner that thrust movement is prevented, but slight tilting about the projection 19 is permitted. Therefore, run-out of a rotor and generation of noise do not occur.