Driving unit for sampling devices.

摘要

The present invention briefly refers to a driving unit (1) for a device for tissue-sampling. The device comprises in addition to the driving unit a needle unit comprising a hollow outer needle (7a) and slidably disposed therein an inner needle (7b), the driving unit (1) being used to propel the needles (7a, 7b). The driving unit comprises a driving device for each needle and each driving device in turn comprises a spring mechanism adapted to be pre-tensioned. The driving unit in addition comprises an inner guide sleeve (3) containing two successive needle holders (4a, 4b) adapted to be shifted in relation to each other in the longitudinal direction of the sleeve and adapted to be pre-tensioned in the same direction for propelling the needles (7a, 7b) with the aid of one spring (5a, 5b) each and which are provided with releasable locking means (33a, 33b). A manual triggering device (6) is provided for releasing the one needle holder (4b) which in turn is adapted during the final phase of its propulsion to release the other needle holder (4a). A tensioning sleeve (2) which rotatably surrounds the guide sleeve (3) is provided with cam surfaces cooperating with the needle holders (4a, 4b) to pre-tension them against the spring force.