Abstract: A heat recovery apparatus for an indoor fireplace includes a plenum chamber of low profile box-like construction having a front extremity with a portion that permits forced entry of air and a horizontally spaced portion that permits emergence of heated air. A divider wall centered within the chamber between the entry and emergence portions produces a passageway that controls the flow of air within the chamber.

Abstract: A trigger mechanism is provided for a water heater fail safe valve assembly which automatically shuts off the flow of water to a water heater when leakage of water from the water heater is detected in an underlying catch tray. The trigger mechanism includes a vertical housing having a drive rod which is upwardly urged by a spring and holds a resilient valve closing component. A cam member holds the drive rod down, representing the open state of the valve. An accumulation of water in the catch tray causes the cam member to release the drive rod to an upper position which closes the valve.

Abstract: Gypsum boards are bent to curved shape by placing a water dampened flat rectangular gypsum board upon a resiliently bendable panel positioned below a bender shell having a wall of arcuate cylindric contour which grips a margin of the gypsum board, and rolling the bender shell upon the gripped board to produce bending. A circular cylindrical weight rolls within the bender shell to apply compressive force upon the gypsum board during the bending process.

Abstract: An economically operated low cost wheeled vehicle that accommodates a single driver occupant is propelled by power provided by a controllable combination of pedaling action of the driver, an internal combustion engine and an electric motor. The vehicle is elongated upon a center axis between a front extremity and a rear extremity having a single, axially centered wheel that drives the vehicle.

Abstract: A drive-train for a fuel-efficient wheeled vehicle includes a first internal combustion engine and a second internal combustion engine of lesser power adapted to drive a generator. An electric motor is adapted to drive the vehicle primarily during cruising mode operation. The first engine is employed primarily to provide maximal power to the vehicle for acceleration, hill-climbing and towing. The power from both the motor and first engine can be selectively combined for varied conditions of operation of the vehicle.

Abstract: A fuel-efficient automotive vehicle is provided having a power train including a primary internal combustion engine, an auxiliary engine, and a coupling system which selectively transfers power from the auxiliary engine to the primary engine when the speed of operation of the auxiliary engine equals the speed of the primary engine. The speeds of both engines are controlled by separate gas pedals conventionally located within the vehicle. The primary engine is of smaller power and better fuel efficiency than an engine which would generally be required by the vehicle. Although the primary engine can maintain the vehicle at a cruising speed, it relies upon the added power of the auxiliary engine for acceleration and hill-climbing.

Abstract: Apparatus for preventing theft of a buss bar connected to electrical conductor and grounding cables is provided in the form of a box-like enclosure of thick metal construction which confines the buss bar and has an elongated access opening permitting passage of cables into the enclosure. An aperture within the bottom of the enclosure permits downward emergence of a grounding cable attached to the buss bar.

Abstract: An acoustic assembly including a thin sound absorbing panel supported by foldable mounting brackets is adapted to be mounted upon the walls of an indoor listening enclosure. The space behind the panel functions as an acoustic diffusion chamber which augments the acoustic performance of the panel. A number of such assemblies are employed in a manner such that the panels are offset from the wall and downwardly angled.