| 摘要 |
A shape memory actuator is described. The shape memory actuator has a supporting body, a driven element slidably mounted on the supporting body for movement between a stable rest position and a stable operative position, a driving element that drives the driven element, the movement of the driving element being determined by a SMA wire and by first resilient return means acting to return the driving element to the rest position upon deactivation of the SMA wire, second resilient return means acting on the driven element in opposition to the SMA wire, engaging means suitable to achieve at the operative position a reversible engagement between the driven element and the supporting body, either directly or indirectly, said engagement being able to resist the action of second resilient return means, and a control system for the engagement and disengagement of the engaging means. |
| 主权项 |
1. A shape memory actuator, comprising:
a supporting body, a driven element slidably mounted on said supporting body for movement between a stable rest position and at least one stable operative position, a driving element, suitable to drive said driven element, moving between a stable rest position and at least one operative position corresponding respectively to said stable rest position and said at least one stable operative position of the driven element, at least one shape memory alloy (SMA) actuating member suitable to provide the movement of said driving element between its rest position and its operative position(s), first resilient return means acting in opposition to said SMA actuating member so as to return the driving element to its rest position upon deactivation of the SMA actuating member, second resilient return means acting on the driven element and suitable to return the driven element to its rest position upon deactivation of the SMA actuating member, engaging means suitable to achieve at the operative position(s) a reversible engagement between the driven element and the supporting body, either directly or indirectly, said engagement being able to resist the action of said second resilient return means, and a control system for the engagement and disengagement of said engaging means, said control system including a rotating member pivotally mounted on the supporting body and connected to the driving element through connecting means such that said rotating member can be driven into rotation by the driving element only upon activation of the SMA actuating member but not when the driving element is returned to the rest position upon deactivation of the SMA actuating member, the rotating member being suitable to rotate alternatively clockwise and counter-clockwise at each following activation of the SMA actuating member, a pivoting axis of the rotating member being substantially perpendicular to a sliding axis of the driving element,
wherein the means connecting the driving element to the rotating member consist of a substantially inverted U-shaped bridge having a first end pivotally mounted on the driving element with a pivoting axis substantially parallel to the pivoting axis of the rotating member and a second end slidably engaged in a slot formed in the rotating member and shaped such that ends of the slot are located at different angular positions relative to the pivoting axis of the rotating member in a plane perpendicular thereto. |
