Abstract: A device and method for venting a conduit and allowing fluid flow through the vented conduit includes an upstream conduit, downstream conduit, and a support for holding the upstream and downstream conduits with their upstream and downstream passageways aligned and maintaining a gap between the adjacent ends of the conduits. The upstream passageway includes an acceleration nozzle for accelerating the velocity of the fluid flow so that the pressure exerted by the fluid on the walls of the upstream passageway is substantially reduced and the reduced pressure is maintained across the gap. The downstream conduit includes a downstream passageway which maintains the accelerated velocity of the primary fluid and which conducts accelerated fluid to a deceleration nozzle. A plurality of the devices may be connected in series and/or multiple gaps may be created between the conduits using intermediate conduits in order to create multiple gaps.

Abstract: A fluid injection device and method includes an upstream conduit, downstream conduit, a support for holding the upstream and downstream conduit with their upstream and downstream passageways aligned and maintaining a gap between the adjacent ends of the conduits, and a secondary fluid source connectable to the gap for injecting secondary fluid into the gap and downstream throat. The upstream passageway includes an acceleration nozzle for accelerating the velocity of the fluid flow so that the pressure exerted by the fluid on the walls of the upstream passageway is substantially reduced and the reduced pressure is maintained across the gap. The downstream conduit includes a downstream passageway which maintains the accelerated velocity of the primary fluid and which conducts the accelerated fluid to a deceleration nozzle. The secondary fluid source injects secondary fluid into the gap and downstream conduit at a preselected higher pressure than the fluid exiting the upstream throat.

Abstract: A fluid-conducting swivel includes an upstream conduit, downstream conduit, and support assembly for holding the upstream and downstream conduit with their flow passageways aligned, allowing rotation of one of the upstream and downstream conduit, and maintaining a space between the adjacent ends of the conduit. The upstream conduit includes an acceleration nozzle for accelerating the velocity of the fluid flow to such a velocity that the fluid creates a substantially self-contained fluid jet. The downstream conduit includes a deceleration nozzle for decelerating the velocity of the fluid flow and a downstream throat extending between the deceleration nozzle and the end of the downstream conduit adjacent the upstream conduit. The downstream throat receives the accelerated fluid from the upstream conduit and is sized to substantially prevent expansion of the accelerated fluid and thereby prevent fluid leakage and pressure loss between the upstream and downstream conduit.

Abstract: A fluid supply apparatus includes a pressure reducing valve. The inlet passageway of the valve is connectable to a first fluid supply and the outlet passageway of the valve is connectable to a fluid user capable of generating a subatmospheric pressure. The actuator of the valve biases the valve to a closed position. A pressure sensing line communicates the pressure from the outlet passageway of the valve to the actuator in opposition to bias of the actuator. The presence of a subatmospheric pressure at the outlet passageway of the valve will move the actuator and valve towards the open position allowing fluid to flow from the first fluid supply to the fluid user with the valve reducing the non-subatmospheric pressure of the fluid in the first fluid supply to the sub-atmospheric pressure of the outlet passageway. A flow dividing vane is provided in the valve between the orifice of the valve and the outlet passageway in order to minimize pressure fluctuations in the outlet passageway.

Abstract: A control valve and switch assembly for automatic control of the pressure in a high pressure fluid system, such as in car washing apparatus, and comprising a housing having a fluid chamber therein providing communication between a pressure fluid source, such as a pump, and a fluid discharge valve, such as a spray nozzle, a fluid outlet passage provided in the housing in communication with the pressure chamber; a primary pressure switch secured to the housing and open to the pressure within the pressure chamber for selective opening and closing; the primary pressure switch being operably connected between a power supply and a motor starter for selective activation of the motor starter; an unloader valve in communication with the outlet passage and responsive to the pressure therein for selective opening to bleed excessive pressure from the pressure chamber to a fluid return line, and a secondary pressure switch secured to the housing and open to the return pressure; the secondary pressure switch being operably