Abstract: An electric motor comprises a rotor rotational position indicator formed internally with a pole field portion of a rotor thereof, and a notch disposed between the pole field portion and the rotor rotational position indicator for suppressing the magnetic influence, the notch being filled with nonmagnetic materials. By virtue of the notch, the pole field and its magnetic influence upon a sensor can be suppressed, whereby appropriate home position and incremental pulses can be generated to enable accurate detection of a rotational position of the rotor.

Abstract: A ball and piston valve for controlling the flow of hydraulic fluid to a motive means have the ball and piston spring biased in opposing directions and with both initially subject to a first hydraulic fluid pressure that allows the springs to cause the ball to be unseated from its seat whereby fluid is directed to a fluid tank and wherein the ball is of sufficiently larger diameter than the piston that upon an increase in fluid pressure the ball is seated and remains seated when the pressure drops to the first hydraulic fluid pressure whereby the motive means to which the fluid is directed when the ball is seated does not have a sudden lurch upon a subsequent increase in pressure.

Abstract: A hydrostatic continuously variable transmission includes a closed hydraulic circuit comprising a hydraulic pump, a hydraulic motor, and an oil supply passage connected between the hydraulic pump and the hydraulic motor. The hydraulic pump selectively generates a first oil pressure lower than a first predetermined pressure level, a second slowly-changing oil pressure higher than the first predetermined pressure level when the transmission is in normal operation, and a third rapidly-changing oil pressure higher than a second predetermined pressure level higher than the first predetermined pressure level when the transmission starts to operate.