Abstract: Device for varying the delivery pressure of a jet washer comprising a positive-displacement pump operated by a single-phase electric motor powered by alternating current and having a delivery nozzle of predetermined cross-section, and electronic means for controlling and regulating the motor feed voltage to vary its speed of rotation.

Abstract: An intermediate sleeve (30) to be rigidly connected to the end of the motor shaft (11) is provided, having an inner surface (32) of frusto-conical shape adapted to fit the frusto-conical surface (12) of the motor shaft (11), and a cylindrical outer surface (31), and having at least one rib (33), projecting radially from the cylindrical outer surface (31) and positioned to the side thereof; the end of the pump shaft (21) possesses an axial cavity (22) having a cylindrical surface (23) adapted to engage as an exact fit the outer surface (31) of the sleeve (30), and has at least one projecting axial element (25), arranged to lie axially alongside said rib (33) of the intermediate sleeve (30), and to interfere therewith during rotation.

Abstract: A hydraulic cleaning unit comprising a high pressure pump (1) arranged to feed a service lance via a hose (10), the pump delivery conduit opening to the outside via a stub shaped as the male part of a usual rotatable quick connect coupling.

Abstract: An intermediate sleeve (30) to be rigidly connected to the end of the motor shaft (11) is provided, having an inner surface (32) of frusto-conical shape adapted to fit the frusto-conical surface (12) of the motor shaft (11), and a cylindrical outer surface (31), and having at least one rib (33), projecting radially from the cylindrical outer surface (31) and positioned to the side thereof; the end of the pump shaft (21) possesses an axial cavity (22) having a cylindrical surface (23) adapted to engage as an exact fit the outer surface (31) of the sleeve (30), and has at least one projecting axial element (25), arranged to lie axially alongside said rib (33) of the intermediate sleeve (30), and to interfere therewith during rotation.

Abstract: A pumping unit, consisting of two side-by-side identical pumps (1) linked together, each comprising a star arrangement of pistons (9) which at one end are linked to a shaft (7) with a crank (77), and at the other end comprise respective pumping diaphragms (11) housed in corresponding operating chambers (13), each chamber (13) being provided with an intake valve (130) and a delivery valve (131), comprises a common intake or delivery manifold (3) located between the facing sides of said two pumps, and having a single branch for connection to the supply of fluid to be pumped, or to the device using the pumped fluid, and respective branches for connection to said operating chambers for said diaphragms.

Abstract: High pressure pump, particularly for water, containing a sealed chamber containing, partially in an oil bath, an inclined disc keyed onto the shank of a socket bush arranged to receive a drive shaft, the bush being received in a hole in the base of the chamber by way of a roller cage and a lip gasket, the inclined disc engaging the ends of pumping pistons to operate them with reciprocating motion, within the chamber base there being provided at least one conduit which connects a region in proximity with the lateral wall of the chamber to the bush-receiving hole within the space between the roller cage and the lip gasket.