Abstract: An engine-driven device comprising a keel-less boat body consisting of at least two parallel, spaced, inflated tube bodies (1, 2) and comprising a substantially rigid or firm bottom (6) which is disposed between said tube bodies. A propeller propulsion (25) together with the steering means (27) and with control means (31, 32) for the propulsion are mounted on the bottom, said propeller propulsion (25) being mounted in a raised position.

Abstract: A keel-less “vehicle” (boat, boat body, gliding device or locomotive device or boat device) is to be designed in such a way that it is equally suitable for use, preferably for rescue missions, on water and ice surfaces. For this purpose, an engine-driven locomotive device comprising a catamaran-like main body of at least two parallel, mutually spaced, inflatable tube bodies (1, 2) and a bottom (6) disposed between said tube bodies at a distance from the respective tube body underside (4) and a propeller propulsion (25) supportable on the vehicle body is suggested.

Abstract: The invention relates to a method for the metered, pulsed pumping of fluid media under high pressure, in which a pressure surge resulting from the stored, kinetic energy of an electromagnetically driven armature element of a reciprocating pump is transmitted via a blocking element to a working fluid, which is enclosed in a pressure space connected to a spraying device, resulting in a predetermined quantity of the working fluid being conveyed out of an spraying unit, the stored, kinetic energy of the armature element being abruptly transmitted first of all to an operating fluid, which is enclosed in a pressure-accumulating space arranged upstream of the pressure space, inducing a pressure surge which is transmitted in the operating fluid in an expanding manner to the blocking element and from the blocking element to the working fluid.