| 摘要 |
A dart has a unitary plastics flight of cruciform cross-section, the four wings being joined directly together at the spine. Before the flight is fitted to the shaft of the dart, the wings are folded flat, one pair on each side of the spine and an aperture is cut through the spine and a small metal cap fitted into it. The flight is unfolded to its cruciform cross-section and the wings fitted into slits in the end of the shaft. The cap fits over the tail end of the shaft to urge together the prongs formed by the slits and to cover the open ends of the slits. |
