Abstract: The present invention relates to a valve with an actuator (3) essentially made of shape-memory alloy (SMA) and provided with means for controlling the activation temperature of the actuator, wherein the means comprises a reverse biasing mechanism (2).

Abstract: With the use of shape memory elements a series of devices can be made which change shape at small changes of the environmental temperature. The devices may be composed of a shape memory element and a bias element, in such a way that the thermal hysteresis of the device becomes lower than the intrinsic thermal hysteresis or the shape memory element. The devices may be used in jewelry that is adapted to change shape or configuration when subjected to temperatures in the region of the body of a wearer.

Abstract: A piece of jewelry (10) is disclosed, comprising first and second substantially opposing end portions (14, 16), at least one said end potion being moveable from an open state A in which said end portions (14, 16) are spaced apart towards a closed state B in which said end portions (14, 16) are spaced apart by, a reduced gap or are substantially engaged. The piece of jewelry (10) comprises at least a section (12a) made from a shape memory material and said shape memory material is adapted, at or above a predetermined temperature Ta, to bring said end portions (14, 16) towards each other. This occurs preferably when said shape memory material is placed in the region of a body part of a wearer such that shape memory effect is used in co-operation with body temperature to fit said piece of jewelry to its wearer whist simultaneously causing, a change in externally visible shape or configuration or the jewelry.