| 摘要 |
<p>The device (1) has an axially moving inner shaft (6) with the cutting element (22) at its lower end provided with a helical cutting edge (23) guided in a complementary groove at the inner surface of a protection cap (7). When the device (1) is inserted into the affected body area against the forces of a spring the protection cap (7) is pushed back, revealing the cutting element (22) until the protection cap (7) itself has entered the body. A too quick retraction of the cutting element is prevented by an integrated control element in the shape of a sleeve with teeth at its lower edge.</p> |
