| 摘要 |
<p>An accessory for an injection device comprises a protective shield 1 for surrounding the needle 2 and having inner and outer shield parts 3, 5 which are movable relative to one another from a contracted position, in which the point of the needle projects from the shield to enable an injection to be effected, to an extended position, in which the point of the needle is shielded by the shield. The shield is biased towards its extended position by a spring 8, and a locking tongue 25 within a cutout 26 in the wall of a collar 6 forming part of the outer shield part 5 is provided to lock the shield in its extended position and prevent the point of the needle from being exposed solely by application of pressure to the end of the shield in the direction of contracting movement. The locking tongue 25 is pivotable within the cutout 26 between a locking position and a disengaged position and is resiliently biased towards its locking position so that, during movement of the shield from its contracted position to its extended position, the locking tongue (25) overrides a shoulder 34 on the inner shield part 3 and, in so doing, is pivoted from its disengaged position into its locking position by resilient action so that it engages behind the shoulder 34 to retain the shield in its extended position. Such an arrangement permits reliable locking using only a weak spring.</p> |
