| 摘要 |
An actuator ( 10 ) for a heart assist device. The actuator ( 10 ) includes an inflatable balloon ( 12 ) and a shroud or wrap ( 14 ). The inflatable balloon ( 12 ) has a first body portion ( 22 ), a second body portion ( 26 ) and a flexure region joining ( 24 ) the first ( 22 ) and second ( 26 ) body portions. The shroud or wrap ( 14 ) is positioned adjacent the first body portion ( 24 ) and has a peripheral extent at least equal to the peripheral extent of the balloon flexure region ( 24 ). The balloon ( 12 ) and the shroud or wrap ( 14 ) are shaped such that the shroud or wrap ( 14 ) restrains a part of the balloon first body portion ( 22 ) at or near the flexure region ( 24 ) against displacement towards the shroud or wrap (outward displacement) past a predetermined limit but allows unrestrained displacement away from the shroud or wrap (inward displacement). |
