Abstract: A pressure washer for delivering a liquid under high pressure has an inlet conduit connected to a liquid supply and an outlet conduit connected to a spray nozzle which can be operated to control the delivery of liquid through the nozzle. A bypass conduit enables recirculation of the liquid from the outlet conduit to the inlet conduit. A bypass system, disposed between the outlet conduit and the bypass conduit, includes a shuttle valve which moves between first and second positions at which it respectively blocks or opens the liquid path from the outlet conduit to the bypass conduit.

Abstract: A nozzle assembly for producing a mousse-like mixture of air and a foamable liquid (preferably a detergent) includes a housing defining a passageway having an upstream and a venturi tube located in the passageway downstream of a mixing chamber also located in the passageway. Openings are formed in the housing to permit a first stream of ambient air to enter into the mixing chamber. The foamable liquid is injected into the mixing chamber and then into the venturi tube in such a manner that ambient air is pulled into the mixing chamber through the openings and is mixed with the foamable liquid as it passes through the venturi tube and a mousse-like mixture of air and the foamable liquid is created downstream of the venturi tube. The resulting mousse travels through the passageway and out the downstream end of the passageway.

Abstract: A pressure washer for delivering liquid under high pressure has an inlet conduit connected to a liquid supply, an outlet conduit connected to a spray nozzle with a valve which is selectively openable for spraying liquid and a plurality of piston operated pumping cylinders connected in parallel between the inlet conduit and the outlet conduit. A bypass conduit recirculates liquid from the outlet to the inlet conduit. A valve in the bypass conduit selectively permits leakage from the outlet conduit when the spray nozzle valve is open and opens communication between the outlet conduit and the bypass conduit when the spray nozzle valve is closed and pressure builds up in the outlet conduit. Each piston in a pumping cylinder is driven to reciprocate through its pumping cylinder. The piston also moves laterally because there is an eccentric connection between the piston and a common rotary pin for each of the pistons of each of the pumping cylinders.

Abstract: A spraying device comprises a nozzle casing surrounding an interior which holds a nozzle block and a conduit coupler therein. The nozzle block and the coupler are axially aligned, a front wall of the coupler facing a rear wall of the nozzle block. The nozzle block and the coupler are relatively rotatable, enabling the front wall of the coupler to rotate relative to the rear wall of the nozzle block. A plurality of spray pattern forming apertures pass through the nozzle block, from the rear to the front wall thereof. A fluid passage in the coupler has a liquid outlet on the front wall of the coupler that is sealingly disposed against the rear wall of the nozzle block, eccentrically to the axis of rotation of the coupler in a manner which permits the liquid output to be brought into fluid communication with any one of the spray generating apertures.