Sub-chassis orienting connectors for a motherboard and mounted to a panel prevents connector rotation

Abstract

A sub-chassis bracket attached to a horizontal motherboard has holes: (a) through which the connectors pass and that space the connectors apart by an intended nominal amount; and (b) that allow the connectors to shift horizontally as needed to form the mechanical path from a particular spacing on the motherboard to a front panel, with its own actual particular spacing, and to which panel the connectors are each fastened with a nut. The nuts are have a symmetrically tapered or curved surface on the side that contacts the outside of the panel, whose holes therethrough are somewhat oversize. The nuts individually center the connectors in their respective panel holes, and draw each connector perpendicular to the panel. To provide a particular connector feature orientation, and to prevent the connectors from rotating and disturbing that orientation during the tightening of the nuts, each connector has a central region of increased diameter that has two flats and that forms a shoulder. The shoulder bottoms out in a stepped hole in the sub-chassis, the larger diameter of which accepts the shoulder and is of a shape that is the complement of the diameter with the flats. This prevents the connector from rotating, although does not interfere with the modest amounts of connector shifting in the sub-chassis bracket.