Abstract: A rotor assembly in which the front and back ends of the rotor are coupled by a shaft assembly extending therethrough. Preferably, the shaft assembly includes a slip joint, such that the shaft is able to accommodate for thermal expansion of the assembly, while maintaining a torsional and bending moment coupling between the front and back ends of the rotor. The rotor assembly is particularly advantageous for use in superchargers having large acceleration and pressure increase requirements, such as superchargers utilized in drag racing. However, the rotor assembly may also be utilized in other devices such as blowers, compressors, or vacuum pumps which may have large acceleration requirements.

Abstract: A method of numerically controlled grinding for forming a curved profile on a workpiece. A rotary grindstone having an arc-shaped grinding periphery. The rotating grindstone is moved along the target profile of the workpiece as keeping a constant attitude thereof as far as such a condition is satisfied that the spotty contact of the arc-shaped periphery of the grindstone to the target profile is maintained. Immediately before the satisfaction of the condition expires, the attitude of the grindstone is reset to satisfy the same condition.