Abstract: An improved adjustable orifice spa jet is provided for use in a spa, therapeutic bath, and the like, wherein the spa jet supplies a diverging annular flow stream of mixed air and water. The spa jet includes a housing defining a chamber with a cylindrical discharge outlet at one end and a pressurized water and an air inlet at the opposite end. A nozzle includes a hollow eyeball fitting mounted pivotally within the chamber and defining a venturi section for admixture of air and water. The nozzle further includes a diverging annular discharge flow path for discharge flow of the air-water mixture to the spa. In the preferred form, the nozzle is directionally adjustable from within the spa and includes curved swirl vanes to impart a swirling action to the fluid flow for improved massage action. The preferred nozzle further includes an adjustment knob accessible from within the spa to variably select a desired air-water mixing ratio.

Abstract: A device for automatically disabling operation of a pneumatic device, such as an air-actuated pump switch. The device includes a diaphragm exposed to atmospheric pressure on one side and to water pressure on the other. So long as the water pressure is high enough, the diaphragm is held in a position in which it seals a pneumatic port and ensures continuing operation of an air-actuated switch. If the water pressure falls below a preselected level, the port is vented to atmosphere and the air-actuated switch is effectively disabled until the water pressure increases again.