Abstract: A spa water delivery system comprising a reciprocating pumping structure to pump water for reception in a spa zone; and driver structure, including a solenoid body element and a solenoid plunger element, the elements being relatively movable; at least one of the elements containing passage structure to receive water in communication with water to be pumped to the zone.

Abstract: A pool or spa filter comprising a filter unit having porous filter wall structure to pass pool or spa water into the filter unit interior, the unit having a suction outlet; a perforated cover plate in water-passing registration with the outlet; the filter unit and cover plate being endwise interconnected and blocked against endwise inadvertent disconnection.

Abstract: A spa water delivery system, the spa includes a wall structure exposed to a water reception zone, and combination comprising: a water delivery structure associated with the wall structure to deliver water to the zone; a manually operable signaling device carried by the wall structure to be operated by a bather in the water reception zone; a sensor spaced from the signaling device to be out of contact with spa water, and responsive to operation of the signaling device to produce a control signal; whereby the control signal may be used to control a flow characteristic of water flowing via the delivery structure to the zone.

Abstract: In a spa water circulation system, the spa including wall structure facing toward a water reception zone and comprising a plurality of water pumps associated with the wall structure, the pumps spaced about the zone, and oriented to receive water intake from the zone and to discharge water streams into the zone; each pump including water pumping structure, and there being structure for controlling pumping operation of the structure.

Abstract: A spa control circuit is provided for regulating a water circulation and heating system in a spa or hot tub or the like. The control circuit comprises a thermostat circuit and a high temperature limit circuit, both of which receive a temperature signal from a common temperature sensor. A safety circuit responds to sensor failure to prevent operation of the circulation/heating system. A latching relay ensures system reset in the same operational state following a power outage. An arc suppression circuit substantially prevents arc damage to relay contacts subjected to frequent opening and closing in response to on-off cycling of the thermostat circuit. In a preferred form, the control circuit components are mounted within a compact housing having a heat transfer member in heat exchange relation with circulating spa water, whereby the spa water is used to prevent overheating of the control circuit components.

Abstract: Tub apparatus comprising a foamed, resiliently compressible, plastic tub wall having an inner side and an outer side, the tub having an interior to receive liquid, and ports extending through the side wall; a plastic pack having a cavity formed therein; a pump unit received in the cavity and protectively enclosed by the plastic pack; and tubular duct structure connected with the pump unit and extending from the cavity to the ports for circulating liquid between the tub interior and the pump unit.

Abstract: A quiet fluid passing apparatus comprising a fluid passing rotor comprising open porous structure extending along an annular path, the rotor forming passage means to pass fluid through the rotor open porous structure as the rotor rotates; said path having an inner circumference with diameter ID and an outer circumference with diameter OD, and wherein ##EQU1## The quiet, fluid-passing apparatus may include open porous structure in combination with structures, such as blades and honeycomb material, to form rotors capable of moving fluid in axial or radial directions.

Abstract: Tub apparatus comprising a foamed, resiliently compressible, plastic tub wall having an inner side and an outer side, the tub having an interior to receive liquid, and ports extending through the side wall; a plastic pack having a cavity formed therein; a pump unit received in the cavity and protectively enclosed by the plastic pack; and tubular duct structure connected with the pump unit and extending from the cavity to the ports for circulating liquid between the tub interior and the pump unit.

Abstract: A quiet fluid passing apparatus comprising a fluid passing rotor comprising open porous structure extending along an annular path, the rotor forming passage means to pass fluid through the rotor open porous structure as the rotor rotates; said path having an inner circumference with diameter ID and an outer circumference with diameter OD, and wherein ##EQU1## The quiet, fluid-passing apparatus may include open porous structure in combination with structures, such as blades and honeycomb material, to form rotors capable of moving fluid in axial or radial directions.

Abstract: An alarm system includes apparatus to be placed in a room to transmit ultrasonic wave signals that rebound off the room's walls and contents, to, and receive the rebounding signals, and to phase balance the transmitted and received signals in order to detect a subsequently unbalance condition caused by a changed in the rebounding signals due to intrusion activity, which produces an electrical alarm signal. Other circuitry responds to reception of an alarm signal to produce an audible or visible alarm. The alarm signal is typically transmitted over electrical power lines.

Abstract: Combined with vehicle glass window is:(a) a sheet of vinyl plastic material applied to the surface of the window to electrostatically adhere to the window surface and act as a sun shield,(b) the sheet having a thickness less than about 0.02 inch,(c) the maximum cross dimension of the sheet being less than 10 inches, whereby the sheet is easily shifted.