Piercing device with retractable needle

A piercing device 1 comprising a needle 3 and a stud 4, the needle protruding in a first direction (A, fig. 5) from a first slider 5 mounted on a first track (6, fig. 5), the needle moveable along a piercing axis (B-B, fig. 5) between stand-by and piercing positions, the stud being mounted to the second slider 7 and protruding in a second direction, the second slider being mounted on a second track (8, fig. 5) and moveable in the second direction (C, fig. 5); the first slider comprising a first connector part 26 and the second slider comprising a second connector part 29; in a first configuration the first slider is in stand-by position; in a second configuration the first slider is in the piercing position and movement of the first slider is transmitted to the second. The device may further comprise a clamp (35, fig. 1) having a static jaw (36, fig. 1) and a sliding jaw 37 each having a needle aperture (40, fig1); 41, the clamp mounted on a third track (19, fig. 5). Preferably there is a needle sleeve 47 on a third slider 48.