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AssigneeSaes Getters S.P.A.
InventorsStefano ALACQUA, Francesco BUTERA, Matteo MAZZONI
Estimating the term…
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.
Shape memory actuator comprising a supporting body (1), a driven element (3) slidably mounted on said supporting body (1) for movement between a stable rest position and at least one stable operative position, a driving element (5) suitable to drive said driven element (3) 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 (3), at least one SMA actuating member (11) suitable to determine the movement of said driving element (5) between its rest position and its operative position(s), and first resilient return means (9) acting in opposition to said SMA actuating member (11) so as to return the driving element (5) to its rest position upon deactivation of the SMA actuating member (11), characterized in that it further comprises second resilient return means (7) acting on the driven element (3) and suitable to return the driven element (3) to its rest position upon deactivation of the SMA actuating member (11), engaging means (3d, 19;
Shape memory actuator according to any of the preceding claims, characterized in that the driving element (5) is slidably and coaxially mounted on the driven element (3) or slidably mounted parallel thereto.
Shape memory actuator according to any of the preceding claims, characterized in that the first resilient return means consist of one or more coiled springs (9) arranged between the driving element (5) and the driven element (3).
Shape memory actuator according to any of the preceding claims, characterized in that the second resilient return means consist of one or more coiled springs (7) arranged between the supporting body (1) and the driven element (3).
Shape memory actuator according to any of the preceding claims, characterized in that at least one of the engaging means (3d, 19) are magnetic means.
Shape memory actuator according to any of the preceding claims, characterized in that it further includes sensor means suitable to detect the engagement condition of the engaging means (3d, 19;
Shape memory actuator according to any of the preceding claims, characterized in that the SMA actuating member (11) is mounted on the supporting body (1) through resilient means suitable to absorb the contraction of the SMA actuating member (11) in order to serve as a mechanical safety that prevents the rupture of the SMA actuating member (11) in case the driving element (5) and/or the driven element (3) cannot be moved.
Valve (V) including a shutter movable between a stable rest position and at least one stable operative position under the action of an actuator (A), characterized in that said actuator (A) is a shape memory actuator according to any of the preceding claims.
Dependencies are inferred from the claim text.