Abstract:
An electrical interruption device is disclosed in which an overcurrent protective device is provided to interrupt electric current flow on a sustained overcurrent current occurring. The overcurrent protective device is characterized by a plunger which is held in tension against the force of a spring by a low temperature solder, and further in which a sleeve of insulating material, such as silicone, is provided about the plunger. Preferably, the overcurrent protective device includes a housing, with the plunger disposed in the housing and having one end extending therefrom to provide electric communication with the remainder of the electric circuit. The sleeve of insulating material preferably being located about the end of the plunger which extends from the housing. On a predetermined condition causing the solder to melt, the plunger is released and under the force of the spring is moved to a position retracted within the sleeve, interrupting the current flow. Advantageously, the overcurrent protective device may be used together with pulverulent arc quenching material. The sleeve acts to isolate the pulverulent arc quenching material from the plunger and prevent its interference with the plunger as it is moved under the force of the spring.
Abstract:
A sub-miniature valve which provides an actuator of shape memory alloy film coupled so as to move a poppet adjacent to a valve port. The shape memory alloy film actuator is thermally cycled through its phase change transition temperature, resulting in either a contraction or elongation of the actuator. This causes the poppet to move relative to the port and either increase or decrease fluid flow. The shape memory alloy film is biased toward its deformed position when cooled below its transition temperature. The valve can be electrically operated with commonly available voltages, including those used for micro-electronics. The relatively large forces and displacements achieved using the shape memory alloy film provide less restriction and greater flow than in other similarly sized valves.
Abstract:
A fastener having an elongated shank formed of a shape memory alloy, a head at the upper end of the shank, and an annular segment at the lower end of said shank having a deformed cross-sectional shape suitable for insertion into an opening extending through adjacent workpieces. The annular segment has a frusto-conical trained shape that is larger than this opening. The annular segment radially flares from the deformed shape to an approximation of the trained shape when heated above a critical transformation temperature, thereby securing the fastener in place with respect to the workpieces. Alternatively, a sleeve made of a different material (e.g. aluminum) extending over a portion or the entire length of the fastener can be added for improved deformational characteristics, by providing the same frusto-conical shape through axial contraction of the shank.
Abstract:
A maneuverable distal apparatus includes a temperature-activated memory element moving in a first direction to assume a predetermined shape when heated to a predetermined temperature and control means for selectively heating the memory element so that the memory element is moved in the first direction. A spring is provided for yieldably urging the memory element in a second direction away from the first direction upon cooling of the memory element to a temperature less than the predetermined temperature so that the memory element is moved to assume a shape other than the predetermined shape.
Abstract:
A method of forming a heat-resistant product, produced from a polymer composition comprising 40-70 weight % of a thermoplastic elastomer containing a repeating unit derived from ethylene and a repeating unit derived from propylene and 60-30 weight % of an ethylene-vinyl acetate copolymer containing 7.5 weight % or more of a vinyl acetate repeating unit, which comprises blending the polymer composition at a temperature of 160.degree. C. or less, molding it at a temperature of 180.degree. C. or less, and then cross-linking the resulting molded product by irradiating it with an electron beam or by heating to produce a foamed product which has good shape memory characteristics.
Abstract:
A thermal and current sensing switch which brakes an associated electric circuit when an overcurrent is supplied to the electric circuit or the temperature of the electric apparatus rises beyond a predetermined temperature. The thermal and current sensing switch comprises a housing, fixed conductors fixed to the housing with the base ends thereof extended within the housing; a current fuse placed in the housing with the opposite terminals thereof in contact with the fixed conductors; a first spring biasing the current fuse away from the fixed conductors, a second spring pressing the current fuse against the fixed conductors against the force of the first spring, and a temperature sensing element provided between the housing and the second spring. When the ambient temperature rises beyond a predetermined temperature, the temperature sensing element reduces the force of the second spring to allow the first spring to separate the current fuse from the fixed conductors to break the electric circuit. The current fuse and the temperature sensing element are isolated electrically and thermal from each other so that the same are able to function independently.
Abstract:
A plug member adapted for insertion into a tube end seals about its periphery in response to a predetermined activation to prevent fluid flow through the tube. In one embodiment, the plug contains annular rings that expand radially outwardly in response to thermal excitation. In an alternate embodiment, a welding material is forced about the plug periphery to seal with the interior surface of a tube in response to a predetermined activation.
Abstract:
A wig having a shape retaining element for preventing turning-up, distortion and so on of a wig base. This shape retaining element (12) is made of a shape memory alloy whose transformation temperature (Af point) is higher than the surrounding temperature at a location between a surface of a user's head and the wig base during a period for which the wig (10) is worn on the head. The shape retaining element is arranged in position on the side of an inner surface or an outer surface of the wig base (11). When the shape retaining element is deformed into a corrugated configuration due to several uses, the shape retaining element is heated to a temperature equal to or higher than the transformation temperature, whereby the shape retaining element is restored to a beforehand stored shape. Thus, the wig can repeatedly be worn under new condition.
Abstract:
An ornament is disclosed, which is characterized in that a metallic alloy wire provided with a characteristic to show the superelastic effect at room temperature by making the metallic texture Austenite phase is overlapped on both ends and formed into an approximately circular ring shape to form a wound ring. A method of manufacturing the same claimed is that a prime wire of Ni--Ti type alloy is submitted to the cold processing rating from 20 to 50% to form a round or angular wire rod, said wire rod is wound up around a stick or pipe with a fixed outer diameter and submitted to the heat treatment at 300.degree. to 600.degree. C. under restraint of both ends of wire rod to form a wound ring of approximately circular ring shape and simultaneously the superelastic effect is given to said ring at room temperature by making the metallic texture thereof Austenite phase.
Abstract:
The wedging members (15) are introduced between the components (4) at a temperature t0 substantially different from the working temperature ts of the stream generator. The wedging member (15) comprise at least one portion (22) of shape memory alloy having a first configuration at the temperature t0 and a second configuration at the temperature ts, such that the wedging parts (15) have an initial transverse dimension less than the width of the separation spaces between the components (4) at the temperature t0, and a transverse dimension substantially greater than the initial dimension at the temperature ts. The components are wedged automatically at the moment when the installation is brought to the working temperature. The invention is applicable in particular to the anti-vibratory bars disposed in the top part or chignon of a steam generator of a pressurized water nuclear reactor.