LANCET ASSEMBLY AND PIERCING DEVICE

摘要

A piercing device in which it is possible to load an unused lancet assembly into an injector and it is not possible to load a used lancet assembly into the injector. In the piecing device, a cutout is formed in the end on the opening end side of a lancet holder and a plate spring member is fitted to the inner wall of a housing of the injector. One end of the plate spring member is fixed and the other end is free. A hook-shaped part is formed at a forward end region of the free end part. In loading of a used lancet assembly into the injector, the cutout is engaged with the hook-shaped part, rendering the loading impossible. On the other hand, in an unused lancet assembly, the lancet body is fixed in the lancet holder such that a projection of the lancet body is positioned behind the cutout of the lancet holder, and this results that, in loading of such an unused lancet assembly into the lancet holder, the projection pushes and expands the free end part outward to make the cutout not engageable with the hook-shaped part, rendering the loading possible.