Abstract: An improved method is provided for the design of high-efficiency electric machines. The maximum practical value of air gap flux density B.sub.g is selected, consistent with maintaining acceptable noise and vibration levels. The value of B.sub.g selected is then used to determine the dimensions of the stator and rotor laminations so as to result in flux density levels that minimize core loss, stator I.sup.2 R and rotor I.sup.2 R losses, and magnetizing current requirements.

Abstract: An AC motor is provided with a motor housing and a photoelectric sensor associated with the housing. The sensor is part of a motor control circuit which is thereby responsive to the ambient light condition to control the motor by selectively switching At on and off, or alternatively by selectively switching between higher and lower speeds. The control circuit derives its power from the motor's AC input terminals, thereby yielding a self-contained motor control unit, which requires no timer unit and no wiring or mounting by the user. In accordance with another aspect of the present invention, the photoelectric sensor extends through an aperture in a motor housing end cap with the associated control circuitry fitable within the end cap, thereby providing a retrofit for existing motors.

Abstract: A one-piece, plastic, integrally formed deflector for a motor includes a generally annularly shaped shroud portion, an axially offset generally annularly shaped mounting ring portion, and four generally axially extending webs interconnecting them. The deflector may be conveniently mounted to an end bracket with a screw placed through a mounting hole in the mounting ring located at each web such that as the end bracket is assembled to the motor, the shroud portion closely fits nearly adjacent the rotating rotor blades and the inside of the motor shell to restrict the flow of ventilating air through the motor and prevent its re-circulation past the blades.

Abstract: A cylindrical shell for a motor/generator may be formed by cutting a rectangular blank, offsetting an edge, rolling the blank into a cylinder with the offset edge overlapping its opposite edge, punching through the overlapping edges to interlock them and form the cylinder, and then joining a base to the cylinder through a similar interlocking, punching process. In a variation, the base may be simultaneously joined to the cylinder as the edges are punched. Holes, or holes with locating nibs, may be used to align the blank in a cylindrical shape to reliably control the shell I.D. during fabrication.