Abstract: An ejector device having an adjustment characteristic which is stepless variable in dependence of the negative pressure generated by the ejector device. The ejector device comprises a portion (16) for connection with a source of positive pressure which delivers the work pressure to the ejector device (1) to give rise to the ejector action. A portion (2) includes inlet (18) for the member which is intended to use the negative pressure created by ejector device (1). The two portions (16, 2) of the ejector device (1) are stepless movable in relation to each other, and in the space therebetween is an adjustment plate (13) for controlling the suction action obtained by the ejector device (1). The outlet slit (17) of the ejector device (1) is located between the plate (13) and the portion intended for connection with the positive pressure source. The adjustment plate (13) is connected to a stem (10) which is movable in relation to the portion (2) for connection with the negative pressure member.

Abstract: The present invention relates briefly to an improved multi-ejector having at least one set of ejector nozzles (12, 13, 14, 15) arranged successively for evacuating of successively arranged chambers (5, 6, 7) which chambers are in communication with a vacuum collecting compartment (16) through ports (18, 19, 20) provided with valves. At least one additional set of nozzles (24, 25) evacuates a chamber (4) in direct communication with the vacuum collecting chamber (16) and the outlet therefrom is arranged in connection with the chamber (5) in which the lowest negative pressure is existing when the first mentioned set of ejector nozzles (12, 13, 14, 15) is operating.

Abstract: Pump comprising reciprocating pumping means driven by a periodically varying pressure in a hydraulic or pneumatic driving device. The driving device comprises an ejector supplied with a driving medium causing alternating pressure reductions and increases in a pressure chamber by driving a valve body to and from an initial position, the pressure variations in the pressure chamber acting on the pumping means for reciprocating movement thereof.