Abstract: A permanent-magnet piston subassembly (10) for a pipetting apparatus, the piston subassembly (10) extending along a piston axis (K) and comprising a plurality of permanent-magnet arrangements (14a to 14m) that are arranged one behind another along the piston axis (K) with alternatingly opposite polarization directions in such a way that for each two permanent-magnet arrangements (14i, 14j) directly successive along the piston axis, it is the case that magnetic poles located closest to one another along the piston axis (K), of different successive permanent-magnetic arrangements (14a to 14m), are like poles, is characterized in that the piston subassembly (10) encompasses a sheath tube (12), extending along the piston axis (K) constituting a tube axis (H), in which the plurality of permanent-magnet arrangements (14a to 14m) are received.

Abstract: A permanent-magnet piston subassembly (10) for a pipetting apparatus, the piston subassembly (10) extending along a piston axis (K) and comprising a plurality of permanent-magnet arrangements (14a to 14m) that are arranged one behind another along the piston axis (K) with alternatingly opposite polarization directions in such a way that for each two permanent-magnet arrangements (14i, 14j) directly successive along the piston axis, it is the case that magnetic poles located closest to one another along the piston axis (K), of different successive permanent-magnetic arrangements (14a to 14m), are like poles, is characterized in that the piston subassembly (10) encompasses a sheath tube (12), extending along the piston axis (K) constituting a tube axis (H), in which the plurality of permanent-magnet arrangements (14a to 14m) are received.

Abstract: In a diaphragm spring clutch, a clutch driven plate is clampable against a rotatably driven counter - pressure plate by a pressure plate urged by a diaphragm spring. To cushion clutch re-engagements the pressure plate has an annular array of spaced lands facing the diaphragm spring and supporting a resilient fulcrum ring having spanning portions spanning the spaces between the lands, the spanning portions of the fulcrum ring being in contact with respective radial ribs on a face of the diaphragm spring. As the diaphragm spring increasingly urges the pressure plate during a clutch re-engagement, the spanning portions of the fulcrum ring are resiliently deformed by the ribs into the spaces between lands to axially cushion the re-engagement.

Abstract: A clutch cover assembly includes a diaphragm spring acting on a pressure plate through a fulcrum ring which encircles the clutch axis and is disposed in a groove in the pressure plate. The fulcrum ring is a resilient tube. During clutch re-engagements, the cross-section of the tube is resiliently deformed by the load of the diaphragm spring to provide cushioning. The resilient tube can have a slot in its outer periphery. In a first stage of cushioning the tube is deformed so as to close the slot. Thereafter, further deformation of the tube is harder and creates a second stage of harder cushioning.

Abstract: Self-supporting luminescent screens made by applying a releasing agent to the surface of a mechanical supporting structure, having the desired shape, which agent is bound with a binding substance that is volatile at the evaporating temperature of a luminescent screen material, the latter being then deposited in a layer by evaporation onto the prepared supporting surface, until the deposited screen layer reaches a desired thickness, and eventually separating and removing the produced luminescent screen from the supporting structure.