Brushless D.C. motor assembly

摘要

An improved motor assembly including a brushless D.C. motor and an annular member defining a platform for the drive electronics and speed control circuits of the motor. The member is carried on a fixed support within the outer envelope of the motor and includes a thin disk-like body providing a pair of opposed surfaces for mounting the components of the circuits. The fixed support of the motor has a flat annular face surrounding the drive shaft of the motor, and the annular member engages and is secured to the flat face of the support in surrounding relationship to the shaft. In a preferred embodiment, the housing of the motor defines part of the rotor of the motor and is for rotation with the shaft. A flange is secured to the support near the opposite end of the shaft for mounting the motor on a fixed support, such as on the base of a housing forming a part of a disk drive unit. Impeller blades can be secured to one end of the shaft or to the side of the housing to supply cooling air to a region adjacent to the motor.