Abstract: A drive connector for elastomerically coupling a drive shaft to a driven shaft. An elastomeric coupling includes openings on opposite ends that are generally “D”-shaped forming an interference fit with correspondingly shaped ends of the drive shaft and the driven shaft. A web extends transversely within the interior of the elastomeric coupling, limiting the distance that the drive shaft and driven shaft are inserted within the openings of the coupling. The coupling includes a rib that runs longitudinally along its outer length. A sleeve having a groove corresponding in size and shape to the rib is slipped over the coupling and is connected to the driven shaft. The sleeve includes a rigid interior element that is overmolded with an elastomeric material. A cam bearing is fitted over a cam surface on the sleeve and provides a force in one direction, urging a plunger to displace an elastomeric membrane in a pumping cassette, forcing medicinal fluid to flow through the pumping cassette.

Abstract: In a pump chassis (112), spring-loaded members (108a, 108b) engage a pumping cassette (114) to it in a predetermined position. The members each include pairs of latches (110a, 110b) that are each beveled to form a ramp so that the latches and associated members are forced outwardly to enable the pumping cassette to be seated within the pump chassis. The latches engage the pump cassette as it is seated, holding it securely. A release button (138) is attached to a spring-loaded shaft (144) that extends into the interior of the pump chassis. The shaft has a ramp formed on its inner end. When the user depresses the release button, the ramp rides under inwardly extending arms (162a, 162b) provided on the members, forcing the members and attached latches to move outwardly. As the members move outwardly, the pumping cassette is released and readily removed.