Abstract: A control method and a control system for single phase induction motors driven by two-power electronic switch inverter are disclosed. The system fulfills two main tasks i.e. precise motor speed control and maximum motor efficiency control over wide ranges of motor load and speed command without a motor speed feedback.

Abstract: A method and apparatus for picking up dog waste has a container and plurality of claw elements moveable from a first position entirely within the container and a second position outside the container and spaced apart. In retrieving dog waste, the claws may be retracted radially to underlie such waste, and then be axially raised into the container.

Abstract: A control method and a control system for single phase induction motors driven by two-power electronic switch inverter are disclosed. The system fulfills two main tasks i.e. precise motor speed control and maximum motor efficiency control over wide ranges of motor load and speed command without a motor speed feedback.

Abstract: A fastener for securing carpet in place on the treads of staircases or elsewhere includes an anchor member having a boss at one end which extends out of the carpet and a relatively thin flat arm which extends under the carpet and which is fastened to the underlying surface by screws or the like. A longer clamping member has a connector end secured to the boss of the anchor member and extends along the anchor member arm above the carpet to a location beyond that of the arm. The undersurface of the clamping member is stepped downward at that location forming a pressure pad which exerts pressure against the carpet beyond the anchor member arm, the pressure pad surface preferably being roughened to resist lateral motion of the carpet. Lugs on one of the members enter slots in the other to prevent pivotal motion of the clamping member relative to the anchor member.