Abstract: An electronic implement adapted for use in a circuit, and including a shape memory element, such as a shape memory alloy wire, wherein the element, when activated and/or deactivated, is operable to open, close, or otherwise modify at least one characteristic of the circuit.

Abstract: A representative embodiment of the invention provides a thermal actuator for a MEMS-based relay switch. The thermal actuator has an “active” arm that is movably mounted on a substrate. The “active” arm has (i) a thermal expansion layer and (ii) a resistive heater that is electrically isolated from the thermal expansion layer. The thermal expansion layer is adapted to expand in response to a temperature change induced by a control current flowing through the resistive heater, thereby bending the “active” arm and moving that arm with respect to the substrate. Due to the fact that mechanical and electrical characteristics of the “active” arm are primarily controlled by the thermal expansion layer and the resistive heater, respectively, those characteristics can be optimized independently to obtain better operating characteristics for MEMS-based relay switches of the invention compared to those attained in the prior art.

Abstract: A method comprising forming a structural element 115 on a surface 620 of a layer 510 via an electroless plating of nickel or cobalt 130 onto the surface, the layer being rigidly fixed to an underlying substrate 110. The method also comprises etching away a portion of the layer such that a part of the structural element is able to move with respect to the substrate.

Abstract: A microswitch comprises a deformable membrane including two substantially parallel flexure arms, attached to a substrate via at least one end thereof and comprising thermal actuating means. An elongated contact arm, substantially parallel with the flexure arms, is arranged therebetween and attached thereto at the high deformation areas thereof. The contact arm moves in a direction substantially parallel to the substrate upon actuation of the microswitch, and comprises electrostatic holding electrodes and a conducting pad.

Abstract: The present invention provides a bi-directional microelectromechanical element, a microelectromechanical switch including the bi-directional element, and a method to reduce mechanical creep in the bi-directional element. In one embodiment, the bi-directional microelectromechanical element includes a cold beam having a free end and a first end connected to a cold beam anchor. The cold beam anchor is attached to a substrate. A first beam pair is coupled to the cold beam by a free end tether and is configured to elongate when heated thereby to a greater temperature than a temperature of the cold beam. A second beam pair is located on an opposing side of the cold beam from the first beam pair and is coupled to the first beam pair and the cold beam by the free end tether. The second beam pair is configured to elongate when heated thereby to the greater temperature.

Abstract: A doubly-anchored thermal actuator for a micro-electromechanical device such as a liquid drop emitter or a fluid control microvalve is disclosed. The thermal actuator is comprised of a base element formed with a depression having opposing anchor. A deformable element, attached to the base element at the opposing anchor edges, is constructed as a planar lamination including a first layer of a first material having a low coefficient of thermal expansion and a second layer of a second material having a high coefficient of thermal expansion. The deformable element has anchor portions adjacent the anchor edges and a central portion between the anchor portions wherein the flexural rigidity of the anchor portions is substantially less than the flexural rigidity of the central portion. The doubly-anchored thermal actuator further comprises apparatus adapted to apply a heat pulse to the deformable element that causes a sudden rise in the temperature of the deformable element.

Abstract: A bistable MEMS microswitch produced on a substrate and capable of electrically connecting ends of at least two conductive tracks, including a beam suspended above the surface of the substrate. The beam is embedded at its two ends and is subjected to compressive stress when it is in the non-deformed position. The beam has an electrical contact configured to produce a lateral connection with the ends of the two conductive tracks when the beam is deformed in a horizontal direction with respect to the surface of the substrate. Actuators enable the beam to be placed in a first deformed position, corresponding to a first stable state, or in a second deformed position, corresponding to a second stable state, and the electrical contact ensures connection of the ends of the two conductive tracks.

Abstract: In one embodiment of the present invention, a shape memory alloy (“SMA”)-actuated flow controller comprises a number of grille members, each having a long axis and being slideable relative to one another parallel to that long axis. The SMA-actuated flow controller also includes a frame configured to guide the number of grille members, and an actuator disposed within the frame to move at least one of the number of grille members for varying a size of an aperture. Further, the actuator includes an SMA actuator that includes a number of SMA elements each connecting one grille member to another.

Abstract: A microelectromechanical (MEM) apparatus is disclosed which includes a shuttle suspended above a substrate by two or more sets of tensile-stressed beams which are operatively connected to the shuttle and which can comprise tungsten or a silicon nitride/polysilicon composite structure. Initially, the tensile stress in each set of beams is balanced. However, the tensile stress can be unbalanced by heating one or more of the sets of beams; and this can be used to move the shuttle over a distance of up to several tens of microns. The MEM apparatus can be used to form a MEM relay having relatively high contact and opening forces, and with or without a latching capability.

Abstract: A doubly-anchored thermal actuator for a micro-electromechanical device such as a liquid drop emitter or a fluid control microvalve is disclosed. The thermal actuator is comprised of a base element formed with a depression having opposing anchor. A deformable element, attached to the base element at the opposing anchor edges, is constructed as a planar lamination including a first layer of a first material having a low coefficient of thermal expansion and a second layer of a second material having a high coefficient of thermal expansion. The deformable element has anchor portions adjacent the anchor edges and a central portion between the anchor portions wherein the flexural rigidity of the anchor portions is substantially less than the flexural rigidity of the central portion. The doubly-anchored thermal actuator further comprises apparatus adapted to apply a heat pulse to the deformable element that causes a sudden rise in the temperature of the deformable element.

Abstract: A mechanical release mechanism is provided. The mechanical release mechanism includes two structural members in slideable relation one to another. A latch holds one structural member in a latched position relative to the other structural member. A shape memory alloy member disposed within one of the structural members is used to move the latch holding the other structural member thereby allowing relative motion between the structural members.

Abstract: A bistable shape memory alloy (SMA) micro-switch includes a single continuous SMA element such as a nitinol wire that provides bi-directional motion for switching functions. Bifunctional contact arms provide a mechanical force to maintain an open state of the micro-switch in addition to conducting current through a circuit. The SMA element includes first and second segments that are alternately heated above a transition temperature to cause the SMA element to alternate between first and second conformations. A cursor attached to the SMA element moves from a first position to a second position as the SMA element moves from its first to its second conformation. To close the SMA micro-switch, the contact arm is moved from an open position to a closed position through sliding contact with the cursor as the cursor moves from its second position to its first position.

Abstract: A micro electromechanical differential actuator is comprised of a suspension arm structure and/or a bridge structure to make a two-degree-of-freedom and bi-directional motion. The actuator support base can make out-of-plane or in-plane vertical and horizontal motions. The invention is applicable in optical micro electromechanical devices such as optical switches, variable optical attenuators, optical tunable filters, modulators, tunable VCSEL's, grating modulators, micro displays, and RF switches.

Abstract: The invention relates to a microswitch containing conductors located on a first level and conductors located on a second level, where the conductors on the first level are supported by a deformable element which can switch by means of an actuator with a bimetallic effect, and where the effect of this switching is that the gap between the conductors on the first level and the conductors on the second level is modified, characterised in that the actuator with a bimetallic effect consists of resistors in close and localised contact with the deformable element, and in that the resistors are capable, when traversed by an electric control current, of expanding sufficiently under the effect of the heat produced by the passage of the electric command current to cause, by the bimetallic effect, the deformable element to trigger before the heat produced in the resistors has been able to propagate into the deformable element.

Abstract: An apparatus for a thermal actuator for a micromechanical device, especially a liquid drop emitter such as an ink jet printhead, is disclosed. The disclosed thermal actuator comprises a base element and a cantilevered element extending from the base element and normally residing at a first position before activation. The cantilevered element includes a first layer constructed of an electrically resistive material, such as titanium aluminide, patterned to have a first resistor segment and a second resistor segment each extending from the base element; a coupling device that conducts electrical current serially between the first and second resistor segments; and a second layer constructed of a dielectric material having a low coefficient of thermal expansion and attached to the first layer.

Abstract: A bi-stable microswitch (1) including a pair of contacts (6, 7) and an armature (4) movable between a first position and a second position to selectively make or break the pair of contacts, the armature being latched in the second position by a shape memory alloy latch (14), wherein the shape memory alloy latch is caused to deform upon heating so as to permit the armature to return to the first position.

Abstract: Improved microelectromechanical structures include spaced-apart supports on a microelectronic substrate and a beam that extends between the spaced-apart supports and that expands upon application of heat thereto to thereby cause displacement of the beam between the spaced-apart supports. A heater, located on the beam, applies heat to the beam and displaces with the beam as the beam displaces. Therefore, heat can be directly applied to the arched beam, thereby reducing thermal loss between the heater and the arched beam. Furthermore, an air gap between the heater and arched beam may not need to be heated, thereby allowing improved transient thermal response. Moreover, displacing the heater as the arched beam displaces may further reduce thermal loss and transient thermal response by reducing the separation between the heater and the arched beam as the arched beam displaces.

Abstract: An actuation device capable of changing its operating condition between a stable rest position and a stable work position has a monostable actuation unit with a body and at least a shaft movable as a function of the energization available to the actuation unit, and a kinematic motion assembly for converting the movement of the shaft into a bistable actuation, the kinematic motion assembly including a slider linearly movable in response to action of the shaft and a device for converting subsequent linear movements of the shaft in the passage of the slider between the stable positions and the maintaining of the same.

Abstract: A thermal switch having a current carrying switch blade actuator of shape memory metal has a resistance less than 20 milliohms. The actuator is deformed to less than about 8% strain, and a very hard high strength dielectric material is used for a spacer.

Abstract: An actuator with an electrically heatable operating element, the housing of the operating element being held stationary in a mount of a base body, and a transfer element, which comprises two plastic molded parts, is provided between the piston and the element to be adjusted.

Abstract: A sectionalizer assembly includes a mounting structure having upper and lower electrical contacts, a sectionalizer tube, an actuating member mounted to the tube and movable from a non-actuated to an actuated position, and a pivotal latching mechanism having a pivot member, latch arm and catch. The pivot member is mounted to the lower electrical contact and to a lower end of the tube for undergoing pivotal movement relative thereto between locking and releasing positions. The latch arm fixedly attached to the pivot member extends outwardly therefrom and undergoes pivotal movement therewith between the locking and releasing positions. The catch is carried on a lower end of the actuating member and undergoes movement therewith. The latch arm has an outer end fittable within a recess in the catch that is open at least at one side thereof.

Abstract: A thermal fuse device for over-current protection includes a fusing element comprising a conductive strip having a fulcrum point between first and second ends. The fuse strip is connected to first and second terminal pads on a substrate by a first solder joint between the first end and the first terminal pad, and a second solder joint between the fulcrum point and the second terminal pad. The second end of the strip is resiliently pressed against the interior surface of a housing that holds the substrate. The inwardly-directed pressure applied to the second end of the fuse strip by the housing is resisted by the first and second solder joints, whereby the fuse strip remains immobile. A resistive element on the substrate generates heat in response to the flow of current.

Abstract: A microactuator and method of operation is disclosed for use in actuating valves, electrical contacts, light beams, sensors and other elements between different actuation modes. An actuator member comprised of a shape memory alloy layer is mounted on an elastic substrate, and the proximal end of the actuator member is carried by a base. The shape memory alloy material is heated through its phase change transition temperature so that it deforms by changing volume to bend the distal end of the actuator member in a first direction relative to the base. Stress forces in the substrate oppose the bending movement, and when the shape change layer is cooled below the transition temperature the stress forces move the distal in a second direction which returns the shape change layer to its low temperature shape. Electrostatic forces are selectively applied between the actuator member and base for clamping the actuator member in one of its positions.

Abstract: A thermally-actuated switch includes a pair of switch contacts openable or closeable in response to a change in the length of a shape memory metal (SMM) rod. The SMM rod is caused to change its length by having its temperature increased by heat produced when electrical power dissipated in a heating element that is coupled in electrical circuit with the switch contacts. To this end, the heating element is thermally coupled to the SMM rod, such as by a common heatsink. Where the switch is to be openable, the heating element is preferably in series circuit with the contacts, and where the contacts are closeable, the heating element is preferably in parallel therewith.

Abstract: A relay including a control circuit which via a movement creating or actuating arm and a transmission mechanism activates a contact means in order to switch on or switch off a main circuit. The actuating arm includes two elongated parallel parts which are separated by a thermally and electrically insulated layer. The two parallel parts each have a first end fastened to a housing or holder. The two parallel parts each have a second end fixed to each other, forming a movable end of the arm. One or both parallel parts of the arm are provided with a heat creating or producing element. The actuating arm, attached at one end and movable at the other end, together with the heat producing element, constitutes the first part of the control circuit or relay. When a control current flows through the heat producing element, one of the two parallel parts of the arm is heated thereby causing a movement of the movable end of the arm to thereby activate the control means through the transmission mechanism.

Abstract: The invention relates to an electric control device for controlling displacement of a moving element (22) between two predetermined positions, said element (22) being associated with one or two electrically conductive return means (18, 30) having shape memory which exert substantially no return force on the element (22) so long as no electric current is passing therethrough, and which exert sufficient force thereon to displace it when an electric current is caused to pass therethrough, with an electric current being switched through one or other of the return means by a controlling switch (10). Once the moving element has reached the desired predetermined position, the electric current used to move it is interrupted by means of a toggle switch (24) operated by the moving element. The invention is applicable to selecting pneumatic functions, e.g. in the motor industry.

Abstract: A thermally operated snap-acting switch uses a switch arm and tension spring for rotating the switch arm. A thermal-responsive element moves the pivot of theswitch arm relative to the centerline of the spring to actuate the switch. Heater means activates the thermal-responsive element for operating the switch.

Abstract: A thermally actuated switch which embodies an active unit which includes a heat responsive element which is part of an enclosure enclosing electrical resistance elements for heating. Heat is applied internally to the enclosure and cooling is by way of dissipation of heat externally from the enclosure. The thermally responsive element is in the form of a flat plate which expands lengthwise. The plate engages the shorter arm of a pivoted bell crank lever, which along with the leaf spring engages the actuating member to be actuated.

Abstract: A snap-action thermal relay in which a thin sheet of spring material having a central opening is mounted at one point along one edge and is crimped along an adjacent edge to distort the sheet into a slightly convex bowed shape. A heater element in the form of a thin band of metal is anchored at either end to the normally convex surface of the sheet adjacent opposite edges of the sheet, with a bridging member inserted between the band and the sheet to put the band under tension. A printed circuit heating element is applied to the band on the side opposite from the sheet. The tension in the band holds the sheet in a concave bowed condition. Heating of the bank reduces the tension in the band and allows the sheet to snap back to its normal convex bowed condition. This action brings the band into direct thermal contact with the convex surface of the sheet over a substantial length of the band to provide good conductive transfer of heat from the band and heater to the spring sheet.

Abstract: An intermittently operable switch assembly comprises an electrically insulating base having mounted on one surface thereof a first electrical terminal for connection to a power supply, a second electrical terminal for connection to an apparatus to be operated intermittently, and a third electrical terminal for connection to an indicator lamp. On the opposite surface of the base are mounted a first support carrying an armature at one end thereof which is engageable with a first fixed contact and having an electrical winding thereon, a second support including a mounting flange and having a snap action circuit breaker mounted thereon, and a third support having a second fixed contact thereon with which the circuit breaker is arranged to engage. The first, second and third terminals are secured to the base respectively by means of three rivets with which they are respectively electrically connected.

Abstract: A sensor which utilizes the difference in thermal characteristic between two fluids to detect the presence of one fluid or the other. A continuously heated thermal expansion element activates a switch. When the element is brought in thermally conductive contact with a liquid, the heated element drops in temperature, shortening the length of the expansion element and activating the switch.