Abstract: A contact element as part of a plug connector is described, which is mountable in a connector housing and provides a contact zone to establish an electrical connection, which may be disconnected again, with a mating connector having at least one blade. The contact zone has at least two contact parts that are positioned at a distance from each other and are provided to receive the blade, each contact part having two contact points.

Abstract: A modification of frictional state and surface condition of an electrical contact surface to reduce the insertion forces for establishment of an electrical plug connection and also to achieve protection from oxidation and fretting corrosion is provided. By controlled melting of a contact surface that is applied onto a support material, a lubricant film applied onto the contact surface is diffused, by using a laser, substantially without modification into the liquefied contact surface and resolidified together with the latter, so that the lubricant film is incorporated into the contact surface.

Abstract: A fuel supply system, having a housing (1), in which a pistonlike element (5) is disposed longitudinally displaceably in a bore (3) and is guided sealingly in the bore (3) by a guide portion (105). On one end, the guide portion (105) adjoins a first fuel-filled chamber (19), and on its other end it adjoins a second fuel-filled chamber (15). At least one recess (30) extending at least approximately in the circumferential direction is embodied in the guide portion (105) of the pistonlike element (5) and extends over at least part of the circumference of the pistonlike element (5) and, viewed in the longitudinal direction of the pistonlike element (5), has an asymmetrical cross section (FIG. 1).