Abstract: A pump has an inlet opening, an outlet opening, a pump diaphragm comprising an opening, provided with a passive check valve, through the pump diaphragm, and an actuator configured to move the pump diaphragm between a first position and a second position. The passive check valve is configured such that a movement from the first position in the direction toward the second position has a closing effect, and that a movement from the second position in the direction toward the first position has an opening effect, so that a pumping cycle wherein the pump diaphragm is moved from the first to the second positions, and back, causes a net flow from the inlet opening to the outlet opening.

Abstract: A diaphragm pump includes a pump chamber having an inlet opening and an outlet opening. A passive silicon check valve is provided at the inlet opening, and a passive silicon check valve is provided at the outlet opening. The diaphragm pump further includes a metallic pump diaphragm that adjoins the pump chamber.

Abstract: A Peristaltic micropump includes a first membrane region with a first piezo-actor for actuating the first membrane region, a second membrane region with a second piezo-actor for actuating a second membrane region, and a third membrane region with a third piezo-actor for actuating the third membrane region. A pump body forms, together with the first membrane region, a first valve whose passage opening is open in the non-actuated state of the first membrane region and whose passage opening may be closed by actuating the first membrane region. The pump body forms, together with the second membrane region, a pumping chamber whose volume may be decreased by actuating the second membrane region. The pump body forms, together with the third membrane region, a second valve whose passage opening is open in the non-actuated state of the third membrane region and whose passage opening may be closed by actuating the third membrane region. The first and the second valve are fluidically connected to the pumping chamber.

Abstract: A pipetting means includes a micropump comprising a pump chamber with a first opening and a second opening. Furthermore, the micropump includes means for changing the volume of the pump chamber. A first active valve is provided to perform opening and closing the first opening. Furthermore, a second active valve is used to perform opening and closing the second opening. Furthermore, the pipetting means comprises a pipette tip connected to the first or second opening via a pipette channel.

Abstract: A Peristaltic micropump includes a first membrane region with a first piezo-actor for actuating the first membrane region, a second membrane region with a second piezo-actor for actuating a second membrane region, and a third membrane region with a third piezo-actor for actuating the third membrane region. A pump body forms, together with the first membrane region, a first valve whose passage opening is open in the non-actuated state of the first membrane region and whose passage opening may be closed by actuating the first membrane region. The pump body forms, together with the second membrane region, a pumping chamber whose volume may be decreased by actuating the second membrane region. The pump body forms, together with the third membrane region, a second valve whose passage opening is open in the non-actuated state of the third membrane region and whose passage opening may be closed by actuating the third membrane region. The first and the second valve are fluidically connected to the pumping chamber.

Abstract: A disc wheel, particularly for rail vehicles, with a composite metal/plastic structure. In order to make possible simple manufacture with at the same time adequate force transmission, a structure between the hub and the tread comprises a plastic structure comprising two half shells of the same design which are subdivided in sector fashion by spoke-like reinforcement ribs. The reinforcement ribs each have a longitudinal slot into which rib plates are inserted which connect the two half shells to each other. Advantageously, plastic foam is inserted into the cavities of the half shells. All joints between the plastic structure and the hub or the tread are cemented joints.

Abstract: The present rotor blade is constructed as a so-called monocoque or shell type blade for use in large fans and windmill rotors. For this purpose the blade is made of fiber reinforced synthetic material with a differnt orientation of the fibers in different sections of the blade. The transition between the blade proper and the connecting end of the blade is formed by a blade root section which has a connecting end of circular or elliptical cross-section and a wing facing end corresponding in cross-section to the blade cross-section. The blade root section has three zones. In the main leading edge zone including the leading edge and adjacent sides of the blade root section the reinforcing fibers extend in parallel to one another. The fibers also extend unidirectionally in a rear zone forming the trailing edge of the blade root section and in this trailing edge zone the fibers also extend in parallel to one another but at an angle relative to the fibers in the leading edge zone.