Method for forming a sector for a nacelle lip skin

摘要

Forming a sector for a nacelle lip skin from a sheet metal blank via punch by placing the blank against an outer surface of the punch and clamping a trailing edge of the blank in a clamping member that grips a trailing edge of the blank without slippage; gripping a leading edge of the blank, opposite the trailing edge, in a gripping device at a location axially spaced from the punch with sufficient force to permit the blank to flow therethrough in a controlled manner; displacing the gripping device in a first direction, radially with respect to the punch while drawing the blank through the gripper; displacing the gripping device in a second direction, axially with respect to the punch, to draw the blank over the leading edge of the punch and through the gripping device.

主权项

1. A method of forming a sector for a nacelle lip skin from a sheet metal blank comprising the steps of:
providing an arcuate or annular punch or mandrel having an inner surface, an outer surface and a leading edge, said punch substantially corresponding in shape to an inner surface of at least a sector of the nacelle lip skin; placing the blank against the outer surface of the punch and clamping a trailing edge of the blank in a clamp to hold the blank against the outer surface of the punch, said clamp gripping said trailing edge of the blank without slippage; gripping a leading edge of the blank, opposite said trailing edge, in a gripping device, at a location axially spaced from said punch adjacent and in front of the leading edge of the punch, said gripping device gripping said blank with sufficient force to permit the blank to flow therethrough in a controlled manner without tearing or wrinkling; displacing the gripping device in a first direction, substantially radially with respect to the punch, towards the central axis of the punch while drawing the blank through the gripping device; displacing the gripping device in a second direction, substantially axially with respect to the punch, towards and past the leading edge of the punch, to draw the blank over the leading edge of the punch while drawing the blank through the gripping device.