Abstract: A diaphragm pump (1) is provided with an annular working chamber (6) and an annular diaphragm (3), which is fixed on its outer peripheral region (12) and on its inner edge region (13). The inner and the outer diaphragm fixing points are stationary relative to each other, and a drive element (8) connected to a pump drive for deflection of the annular diaphragm (3) contacts between the outer and inner fixing points. The drive element (8) is formed facing the diaphragm with a sleeve or ring shape with a diameter corresponding approximately to the annular working chamber (6) and contacts with one of its annular ends perpendicular to the diaphragm plane on the side of the annular diaphragm (3) facing the pump drive for deflection and for transmission of a back-and-forth movement to the annular diaphragm (3).

Abstract: A plate valve, especially for diaphragm pumps, having a valve plate (8), a valve seat (15), and a valve chamber bounded by a valve housing is provided, with the valve plate being held at the edges thereof. The valve plate (8) is preset under tension elastically in the installation position between outer edge holding devices, with the elastic pretensioning being at least large enough that deformations due to edge clamping can be compensated. Preferably, the valve plate (8) is held at the edge in a positive fit and is preset under tension elastically between its outer edge holding devices in the installation position.

Abstract: An oscillating displacement pump, particularly a diaphragm pump (P) for liquid or gaseous delivery media, having a delivery space which on the one side is delimited by a pump head and on the other side by a delivery element, particularly formed by a diaphragm (6). The delivery element is drivingly connected to an eccentric drive, and an inlet valve connected to an inlet connection and an outlet valve connected to an outlet connection are connected to the delivery space. The pump has a pulsation damper (45) on the pressure side, and also an excess pressure limiting device (27) between the pressure and suction sides, these devices being integrated into the pump head. In use as a liquid pump, an oscillation chamber (16) is integrated into the suction side of the pump head. Pressure peaks are thereby diminished both on the suction side and the pressure side, and a pressure rise on the pressure side is limited to a predeterminable value.

Abstract: A pulsation damper which is used for damping pressure variations in an oscillating positive-displacement pump connected thereto is provided. The pulsation damper includes an inlet connection element, an outlet connection element and a line connecting the elements whereby these three components are connected to at least two damper chambers inside the pulsation damper, the damper chambers being connected in series inside the damper housing. One section of the line connected to the inlet connection element includes a connection channel to a first damper chamber and is joined to a second damper chamber via an inlet throttle element. The second damping chamber is connected to the outlet connection element via an outlet throttle. Damper elements made of an elastic material are disposed within the damper chambers.