| 摘要 |
An endoscopic biopsy instrument 100 comprises an elongate flexible shaft 2, a biopsy device 1 arranged at a distal end of the shaft 2, and operating controls arranged at a proximal end of the shaft 2. The endoscopic biopsy device 1 comprises at least one moveable element 3 that is operable for securing a tissue sample by means of one or more power actuators 6, 7 arranged in a distal portion of the endoscopic instrument 100, wherein the power actuators 6, 7 comprise a shape memory alloy (SMA). The moveable element 3 is actuated by a set of counteracting SMA actuator wires 6/7 coupled to the moveable element 3 and arranged such that contraction of a drive SMA actuator wire 6 actuates a drive movement in a direction from a first position to a second position of the moveable element 3 and elongates a recovery SMA actuator wire 7, and accordingly contraction of the recovery SMA actuator wire 7 actuates a recovery movement in a direction from the second position to the first position of the moveable element 3 and elongates the drive SMA actuator wire 6. |
