Abstract
This paper presents the motor manufacturing technology for brushless DC motors which are used for middle to large size compressor motors and industrial motors, etc.We propose the divided core assembled by partial press-fitting which enables production with small capital investment, in spite of small manufacturing quantities of a wide variety of middle to large size motors. This type of divided core has the following features : (1) Concentrated high-density winding can be achieved, because this type of core is divided in units of pole. (2) The stator can be assembled easily with the core divided in units of pole, by using the press-fitting technique. (3) Divided core assembly with low press-fitting pressure and required accuracy is performed, even if stator becomes large. Based on this technology, compressor motors are fabricated and their characteristics are examined. As a result, compared to conventional compressor motors with a distributed winding structure, weight saving of approximately 20%, downsizing in the axial direction of approximately 30% and motor efficiency improvement of 1 - 3% are achieved.
