| 摘要 |
<p>A mandrel for forming a component with a cavity, the mandrel having a longitudinal axis (A) and defining a cavity profile, the mandrel comprising: a support structure; a plurality of main sectors (20) carried by the support structure and each having a main forming surface; and a plurality of intermediate sectors (30) carried by the support structure and each having an intermediate forming surface; wherein the main sectors (20) and intermediate sectors are alternately arranged around the axis, the main sectors being moveable relative to the support structure between a radially inner main retracted position, and a radially outer main forming position in which each main forming surface defines a part of the cavity profile, and in which the main sectors are spaced apart to define circumferential gaps; and the intermediate sectors (30) being moveable relative to the support structure between a radially inner intermediate retracted position, and a radially outer intermediate forming position in which the intermediate sectors extend into the respective gaps, and in which each intermediate forming surface defines a part of the cavity profile; the mandrel further comprising drive means (68) for moving the main sectors and intermediate sectors from their respective retracted positions to their respective forming positions; wherein the drive means comprises a plurality of drive units, each drive unit being arranged to move at least one of a main sectors and an adjacent intermediate sector from their retracted positions to their forming positions and is configured such that each main sector reaches its main forming position before the adjacent intermediate sectors reach their respective intermediate forming positions; wherein a lost motion connection is provided between each drive unit and the respective main sector.</p> |
