Mechanical Memory Patents (Class 148/402)
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Patent number: 6554039Abstract: A tire includes a toroidal carcass and a tread band. The toroidal carcass includes a central crown and two sidewalls terminating in a pair of annular beads. Each annular bead includes a metallic bead core for anchoring to corresponding bead seats of a wheel rim. The metallic bead cores include at least one annular portion made of a material having characteristics of superelasticity and shape memory. The material having characteristics of superelasticity and shape memory is deformable at ambient temperature in response to a constant force and recovers to an original shape upon removal of the constant force to facilitate mounting the tire on the wheel rim. The wheel rim includes a central cylindrical channel from which branches off, axially and outwardly, from opposite sides, diverging surfaces each terminating in a peripheral flange. The diverging surfaces form the bead seats for respective annular beads of the tire.Type: GrantFiled: October 27, 1999Date of Patent: April 29, 2003Assignee: Pirelli Pneumatici S.p.A.Inventors: Guido Riva, Gurdev Orjela, Syed Khawja Mowdood, Alessandro Volpi, Claudio Villani
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Patent number: 6540849Abstract: A process for treating nitinol so that desired mechanical properties are achieved. In one embodiment, the process comprises the steps of exposing the nitinol to a primary annealing temperature within the range of approximately 475° C. to 525° C. for a first time period, and thereafter exposing the nitinol to a secondary annealing temperature within the range of approximately 550° C. to 800° C. for a second time period. The invention also includes nitinol articles made by the process of the invention.Type: GrantFiled: February 22, 2000Date of Patent: April 1, 2003Assignee: SciMed Life Systems, Inc.Inventors: Paul DiCarlo, Steven E. Walak
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Patent number: 6524406Abstract: A novel shape memory alloy of Fe—Mn—Si system containing at least Fe, Mn, and Si wherein the alloy contains niobium carbide in the structure and is improved in that a sufficiently satisfactory shape memory effect is provided without carrying out a special treatment termed training.Type: GrantFiled: February 9, 2001Date of Patent: February 25, 2003Assignee: National Research Institute for MetalsInventors: Takehiko Kikuchi, Setsuo Kajiwara, Daozhi Liu, Kazuyuki Ogawa, Norio Shinya
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Patent number: 6516146Abstract: An actuator using a novel shape memory alloy which, even when there is a large difference between a transformation start temperature of the shape memory alloy and a heating start temperature, can diminish a time lag based on the temperature difference from the time when an operation start command signal is outputted until the start of movement of an actuating member, thereby causing, the actuating member to start deformation quickly and permitting a driven member to be actuated quickly. When the driven member is moved from an initial position to a reference position in operation, if the amount of movement of the driven member is larger than a normal amount of movement, an electric current larger than an electric current value calculated from the amount of movement is fed to the actuating member which is constructed of the shape memory,alloy, thereby causing the actuating member to be displaced quickly to actuate the driven member quickly.Type: GrantFiled: November 16, 2000Date of Patent: February 4, 2003Assignee: Minolta Co., Ltd.Inventor: Akira Kosaka
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Publication number: 20030000605Abstract: The present invention employs a shape memory alloy that exhibits a two-way shape memory effect and that has a stress-strain property that, in a stress-strain diagram, the stress-strain curve comprises a gentler gradient portion extending with relatively small gradients and a steeper gradient portion extending with relatively great gradients. The shape memory alloy is operated in the region surrounded by the gentler gradient portion, the steeper gradient portion, a practical stress limit line, a straight line connecting the intersection of the practical stress limit line and a strain limit line near shape recovery completion on which the strain of the shape memory alloy reaches a specified value in a state close to the shape recovery completion and the point where the strain is zero at a low temperature in the stress-strain diagram.Type: ApplicationFiled: June 5, 2002Publication date: January 2, 2003Inventor: Dai Homma
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Patent number: 6500282Abstract: A superelastic alloy exhibiting shape memory or pseudoelastic it properties contains about 46.17 weight percent Au and about 53.83 weight percent In. Such alloys containing the superelastic Au—In2 intermetallic compound which exhibits elasticity can be formed into a gasket or seal that can be deformed at low stress levels while additionally having corrosion resistant properties.Type: GrantFiled: February 16, 2001Date of Patent: December 31, 2002Assignee: Honeywell International Inc.Inventors: Robert C. Morris, Dave Narasimhan, Raghib Hasan
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Publication number: 20020189719Abstract: A nickel titanium hafnium copper thin film shape memory alloy having a composition (TiHf)5-55(NiCu)45-50 comprising about 2 atomic percent to about 10 atomic percent copper and the fabrication method of said shape memory thin film by magnstron sputtering using Kr as working gas and conducting the deposition at elevated substrate temperature.Type: ApplicationFiled: April 16, 2001Publication date: December 19, 2002Inventors: Gregory K. Rasmussen, Jinping Zhang, Fenglian Chang, Terry J. Gold
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Publication number: 20020185200Abstract: A process for treating nitinol so that desired mechanical properties are achieved. In one embodiment, the process comprises the steps of exposing the nitinol to a primary annealing temperature within the range of approximately 475° C. to 525° C. for a first time period, and thereafter exposing the nitinol to a secondary annealing temperature within the range of approximately 550° C. to 800° C. for a second time period. The invention also includes nitinol articles made by the process of the invention.Type: ApplicationFiled: February 22, 2000Publication date: December 12, 2002Inventors: Paul DiCarlo, Steven E. Walak
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Publication number: 20020144758Abstract: A Ti—Ni shape memory alloy with ductility, including Ti of 50˜66atomic % in a composition, and in which precipitation of Ti2Ni phases at grain boundaries is suppressed.Type: ApplicationFiled: June 4, 2002Publication date: October 10, 2002Inventors: Akira Ishida, Shuichi Miyazaki
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Patent number: 6461453Abstract: An improved guiding member for use within a body lumen having a unique combination of superelastic characteristics. The superelastic alloy material has a composition consisting of about 30% to about 52% (atomic) titanium, and about 38% to 52% nickel and may have one or more elements selected from the group consisting of iron, cobalt, platinum, palladium, vanadium, copper, zirconium, hafnium and niobium. The alloy material is subjected to thermomechanical processing which includes a final cold working of about 10 to about 75% and then a heat treatment at a temperature between about 450° and about 600° C. and preferably about 475° to about 550° C. Before the heat treatment the cold worked alloy material is preferably subjected to mechanical straightening. The alloy material is preferably subjected to stresses equal to about 5 to about 50% of the room temperature ultimate yield stress of the material during the thermal treatment.Type: GrantFiled: June 7, 2000Date of Patent: October 8, 2002Assignee: Advanced Cardiovascular Systems, Inc.Inventors: Robert M. Abrams, Sepehr Fariabi
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Publication number: 20020119069Abstract: Iron-manganese-silicon-based shape memory alloys comprising:Type: ApplicationFiled: October 25, 2001Publication date: August 29, 2002Inventors: Zuyao Xu, Shipu Chen, Jianfeng Wan, Zhenghong Guo, Jihua Zhang, Yonghua Rong
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Publication number: 20020118090Abstract: The present invention provides actuators and actuator devices that take advantage of a strain gradient variation of an actuator element between a first phase and a second phase. The actuator elements can be positioned in any type of shape. For instance, the actuator element in the first phase can be any type of curved, non-linear or irregular shape as long as a strain gradient along a cross-section of the actuator element can be established. The actuator element in the second phase is positioned in a different shape when compared to the first phase as long as it is in a direction to minimize the strain gradient. Different actions can be generated such as a rotary movement, a linear movement, an expanding movement, or a combined linear and rotary movement. The actuator element could also be configured to generate a linear movement by combining contraction and strain gradient variation.Type: ApplicationFiled: December 19, 2001Publication date: August 29, 2002Inventors: Byong-Ho Park, Friedrich B. Prinz
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Publication number: 20020112788Abstract: An Ni—Ti—Cu shape memory alloy electrothermal actuator element that recovers its original shape by electrical heating, having a wire diameter of 0.5 mm or less, comprising an Ni—Ti—Cu shape memory alloy wire which contains 49.0 to 51.0 at % of Ti, and 5.0 to 12.0 at % of Cu, with the balance being made of Ni, wherein the actuator element has a deterioration rate of shape strain recovery of 0.5% or less after repeating desired times of shape recovery movement.Type: ApplicationFiled: October 22, 2001Publication date: August 22, 2002Inventors: Toyonobu Tanaka, Hiroshi Horikawa, Keizo Iwasaki, Kengo Mitose
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Patent number: 6436223Abstract: A fixture and process for assembly of semiconductor modules. Each module comprises a substrate and a cover attached to the substrate. The fixture comprises a baseplate adapted to accept the substrate and a spring-loading device containing a shape memory alloy spring engaging the cover. The shape memory alloy spring exerts a lesser force at room temperature and an elevated force at the bonding temperature of the bonding agent used to attach the cover to the substrate.Type: GrantFiled: February 16, 1999Date of Patent: August 20, 2002Assignee: International Business Machines CorporationInventors: David L. Edwards, Enrique C. Abreu, Ronald L. Hering, David C. Olson
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Patent number: 6427712Abstract: A novel shape memory alloy (SMA) actuator which responds to changes in ambient temperature. The actuator is capable of operating bidirectionally over a smaller temperature range than conventional SMA actuators by taking advantage of the R-phase characteristics of the SMA material. A coiled SMA spring 14 is provided with an enabled R-phase by limiting recoverable strain in the SMA material to less than about 1 percent. The force of the SMA spring 14 is counteracted by a non-SMA spring 15. The stronger of the two springs 14, 15 controls the position of an actuating element 13, with SMA spring 14 being the stronger spring while in its austenitic phase and being the weaker spring while in its R-phase. Triggering the actuator with entry into the R-phase rather than the martensitic phase during cooling reduces the hysteresis normally associated with an SMA actuator, allowing the actuator to react bidirectionally to smaller changes in ambient temperature.Type: GrantFiled: June 9, 1999Date of Patent: August 6, 2002Assignee: Robertshaw Controls CompanyInventor: Gary Robert Ashurst
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Patent number: 6428634Abstract: A method of processing a Ni—Ti—Nb based alloy which contains from about 4 to about 14 atomic percent Nb and in which the ratio of atomic percent Ni to atomic percent Ti is from about 3.8 to 1.2, comprising working the alloy sufficient to impart a textured structure to the alloy, at a temperature below the recrystallisation temperature of the alloy. Preferably, the alloy is worked at least 10%, by a technique such as rolling or drawing, or another technique which produces a similar crystal structure. The alloy has increased stiffness compared with Ni—Ti binary alloys with superelastic properties.Type: GrantFiled: April 24, 1997Date of Patent: August 6, 2002Assignee: Ormco CorporationInventors: Petrus A. Besselink, Rohit C. L. Sachdeva
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Patent number: 6422797Abstract: The present invention relates to a binding element for binding a stack of documents comprised of loose sheets, having a spine piece and two side pieces, the side pieces being arranged essentially perpendicular to the spine piece. The binding element is made of a shape memory material or has at least part of the binding element made of a shape memory material.Type: GrantFiled: June 15, 1999Date of Patent: July 23, 2002Assignee: Esselte N.V.Inventor: David Pas
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Patent number: 6406566Abstract: The present invention provides a copper-based alloy having high shape memory properties and superelasticity while maintaining an excellent workability, members such as a wire, plate, pipe, etc. made of the copper-based alloy, and methods for producing them. The copper-based alloy has a recrystallization structure substantially composed of &bgr;-single phase, and can be produced by a method comprising the steps of: forming an alloy by cold-working with a particular maximum cold-working ratio; and subjecting the cold-worked alloy to at least one solution treatment for improving a crystal orientation of the &bgr;-single phase, a quenching and an aging treatment. The maximum cold-working ratio is set so that the crystal orientation density of the &bgr;-single phase measured by an electron back scattering pattern method is 2.0 or more in a cold-working direction.Type: GrantFiled: July 10, 2000Date of Patent: June 18, 2002Inventors: Kiyohito Ishida, Ryosuke Kainuma, Yuji Sutoh
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Publication number: 20020069941Abstract: A shape memory alloy step drive mechanism comprising at least one shape memory alloy element (1) with a fixed end and the other end being connected to one end of a lever (2). The lever (2) is provided with a pawl (4) which is located to move on the teeth of a ratchet wheel (5) mounted on a main shaft (6) along with the lever (2). A stopper pin (7) is provided which also guides the pawl (4) on the ratchet wheel (5). A bias spring (9) is provided on a mandril on the main shaft (6) for returning the lever (2) to its original position. A detent wheel (8) with at least one detent lever (10) is mounted on the main shaft (6) to provide the detent torque required to hold the main shaft (6) in position when the lever (2) returns to its original position. A pair of support brackets (11) are provided for supporting and holding the said components together in an assembly.Type: ApplicationFiled: October 16, 2001Publication date: June 13, 2002Inventors: Viswanatha Narasimhiah, Murali Parathasarathy Iyengar Talkao
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Patent number: 6401779Abstract: A tire includes a carcass; a tread band on the carcass; a belt, positioned between the tread band and the carcass, including at least one layer of rubberized fabric; and at least one reinforcing metal strap in the at least one layer of rubberized fabric. The at least one reinforcing metal strap is made of a shape-memory material oriented at about 0° to an equatorial plane of the tire. The at least one reinforcing metal strap has a width of no less than about 1 mm. And the at least one reinforcing metal strap has coils disposed side-by-side in a direction substantially perpendicular to a radius of the tire.Type: GrantFiled: October 27, 1999Date of Patent: June 11, 2002Assignee: Pirelli Pneumatici S.p.A.Inventors: Guido Riva, Gurdev Orjela, Maurizio Boiocchi
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Patent number: 6383305Abstract: To improve the resistance of a solder to strains, especial thermal strains, superelastic particles are incorporated into the solder in a proportion by volume of 10 to 30% approximately. So that this incorporation can be done, the particles are coated with a metal, for example copper, that is wettable by the solder.Type: GrantFiled: June 23, 2000Date of Patent: May 7, 2002Assignee: Thomson-CSFInventors: Jean Chazelas, Olivier Prevotat, Jean-François Silvain, Sandrine Trombert
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Publication number: 20020046783Abstract: Methods of fabricating a free standing thin film of shape memory alloy material, and products made by the methods. A sacrificial layer of a metallic material is deposited onto the surface of a substrate. Then an amorphous shape memory alloy is sputter deposited onto the outer surface of the sacrificial layer. The sacrificial layer is etched away, leaving the thin film free standing, that is separated from the substrate. The thin film is annealed by heating into a crystalline state, with the annealing step carried out either after the film has been separated from the substrate, or while remaining attached to it.Type: ApplicationFiled: July 10, 2001Publication date: April 25, 2002Inventors: A. David Johnson, Vikas Galhotra, Vikas Gupta
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Publication number: 20020046785Abstract: An improved guiding member for use within a body lumen having a unique combination of superelastic characteristics. The superelastic alloy material has a composition consisting of about 30% to about 52% (atomic) titanium, and about 38% to 52% nickel and may have one or more elements selected from the group consisting of iron, cobalt, platinum, palladium, vanadium, copper, zirconium, hafnium and niobium. The alloy material is subjected to thermomechanical processing which includes a final cold working of about 10 to about 75% and then a heat treatment at a temperature between about 450° and about 600° C. and preferably about 475° to about 550° C. Before the heat treatment the cold worked alloy material is preferably subjected to mechanical straightening. The alloy material is preferably subjected to stresses equal to about 5 to about 50% of the room temperature ultimate yield stress of the material during the thermal treatment.Type: ApplicationFiled: June 18, 2001Publication date: April 25, 2002Applicant: Advanced Cardiovascular Systems, Inc.Inventors: Robert M. Abrams, Sepehr Fariabi
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Patent number: 6345792Abstract: A mechanical actuating device for moving an aerodynamic or hydrodynamic surface includes plural flexure members confined in an elastically deformed condition. The flexure members are movable against the force generated by their elastic deformation to move the device into one of at least three stable positions, in which the device, and therefore the aerodynamic or hydrodynamic surface, are held by the force generated by elastic deformation of the flexure members. Since the flexure members are always elastically deformed, the device “snaps” between discrete, stable positions and is held firmly in each. In another embodiment more flexure members can be used to provide additional stable positions. In one application, the actuating device is used as a trailing edge tab for a helicopter or tiltrotor blade to reduce 1/rev vibrations. The device can be actuated manually or electrically using shape-memory alloy wires to snap the flexure members into their various stable positions.Type: GrantFiled: March 9, 2001Date of Patent: February 12, 2002Assignee: Continuum Dynamics, Inc.Inventors: Alan J. Bilanin, Robert M. McKillip, Jr.
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Publication number: 20020007884Abstract: The present invention relates to a semifinished product made from a shape memory alloy having a two-way effect, and to a method for manufacturing the same. An objective in this case is to produce a two-way effect in the shape memory alloy in simple fashion and using only few process steps, so that the semifinished product made of the shape memory alloy at the austenite/martensite phase transition, is able to pass through a large number of deformation cycles, and it exhibits high effect amounts, without requiring a protracted training of the shape memory alloy or externally acting forces. In one single deformation step, a linear, superelastic phase is additionally produced in the shape memory alloy, thereby introducing a restoring force to the shape memory alloy, so that, under the action of this restoring force, the shape memory alloy passes repeatedly through the deformation cycle during the austenite/martensite phase transition.Type: ApplicationFiled: June 28, 2001Publication date: January 24, 2002Inventors: Andreas Schuster, Heinz Voggenreiter
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Publication number: 20020003014Abstract: A method of treating a shape memory alloy to improve its various characteristics and to cause it to exhibit a two-way shape memory effect. A raw shape memory alloy having a substantially uniformly fine-grained crystal structure is prepared and then its crystal orientations are arranged substantially in a direction suitable for an expected operational direction, such as tensile or twisting direction or the like, in which the shape memory alloy is expected to move when used in an actuator after the completion of the treatment.Type: ApplicationFiled: June 4, 2001Publication date: January 10, 2002Inventor: Dai Homma
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Patent number: 6328822Abstract: The functionally graded alloy having a composition comprising 3-10 weight % of Al, 5-20 weight % of Mn, the balance being substantially Cu and inevitable impurities has a first portion composed essentially of a &bgr;-phase, a second portion composed essentially of an &agr;-phase and a Heusler phase, and a third portion having a crystal structure changing continuously or stepwise from the first portion to the second portion. The functionally graded alloy can be produced by forming a copper-based alloy having the above composition, keeping it at 500° C. or higher and rapidly cooling it, and then subjecting it to an aging treatment by a gradient temperature heater. Such functionally graded alloy can suitably be used for guide wires and catheters.Type: GrantFiled: June 25, 1999Date of Patent: December 11, 2001Inventors: Kiyohito Ishida, Yoshikazu Ishii, Ryosuke Kainuma
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Publication number: 20010035236Abstract: A Ti—Ni shape memory alloy with ductility, including Ti of 50˜66 atomic % in a composition, and in which precipitation of TI2Ni phases at grain boundaries is suppressed.Type: ApplicationFiled: March 15, 1999Publication date: November 1, 2001Inventors: AKIRA ISHIDA, SHUICHI MIYAZAKI
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Publication number: 20010023723Abstract: A novel shape memory alloy of Fe—Mn—Si system containing at least Fe, Mn, and Si wherein the alloy contains niobium carbide in the structure and is improved in that a sufficiently satisfactory shape memory effect is provided without carrying out a special treatment termed training.Type: ApplicationFiled: February 9, 2001Publication date: September 27, 2001Inventors: Takehiko Kikuchi, Setsuo Kajiwara, Daozhi Liu, Kazuyuki Ogawa, Norio Shinya
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Patent number: 6280539Abstract: An improved guiding member for use within a body lumen having a unique combination of superelastic characteristics. The superelastic alloy material has a composition consisting of about 30% to about 52% (atomic) titanium, and about 38% to 52% nickel and may have one or more elements selected from the group consisting of iron, cobalt, platinum, palladium, vanadium, copper, zirconium, hafnium and niobium. The alloy material is subjected to thermomechanical processing which includes a final cold working of about 10 to about 75% and then a heat treatment at a temperature between about 450° and about 600° C. and preferably about 475° to about 550° C. Before the heat treatment the cold worked alloy material is preferably subjected to mechanical straightening. The alloy material is preferably subjected to stresses equal to about 5 to about 50% of the room temperature ultimate yield stress of the material during the thermal treatment.Type: GrantFiled: February 7, 2000Date of Patent: August 28, 2001Assignee: Advance Cardiovascular Systems, Inc.Inventors: Robert M. Abrams, Sepehr Fariabi
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Patent number: 6258182Abstract: The disclosed &bgr; titanium alloys contain alloying elements of molybdenum between 10.0 and 12.0 weight percent, aluminum between 2.8 and 4.0 weight percent, chromium and vanadium between 0.0 and 2.0 weight percent, and niobium between 0.0 and 4.0 weight percent. Orthodontic arch wires and appliances of nickel-free &bgr; titanium alloys having pseudo-elastic properties associated with stress-induced martensitic transformation. These arch wires and appliances were found to possess a high strain recovery up to 3.5% strain of deformation, a lower stiffness yielding relatively constant force for tooth movement and improved formability over that of pseudo-elastic nitinol. Eyeglasses having parts made of such materials can be welded. Stents made of this material avoid problems which a certain percentage of the population have when nickel is included within alloys used in the human body. Other medical devices which are used in the body also have this benefit.Type: GrantFiled: March 5, 1999Date of Patent: July 10, 2001Assignee: Memry CorporationInventors: L. McDonald Schetky, Ming H. Wu, Chi-Yuan Loi, Charles J. Burstone
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Patent number: 6238496Abstract: A method for post-production precision modification and enhancement of pre-existing shape memory alloy (SMA) forms to precisely alter their chemical composition and properties and produce greater accuracy and versatility. The present process includes carefully controlled electrodeposition or electroless deposition of alloying agents such as Nickel, Copper, or other elements on the surface of the pre-existing SMA form to produce the desired shape memory properties, followed by application of a protective coating, then high temperature heat treatment in combination with gentle physical kneading to speed up the homogenization process (thermal diffusion) and produce rapid diffusion of the plated metal throughout the form. The present method may also use the skin effect of AC current for localized heat treatment of the SMA form and neutron activation tracer analysis for in-line quality control and diagnostics. The process can also be used to impart shape memory properties to non-SMA alloy forms.Type: GrantFiled: June 30, 1999Date of Patent: May 29, 2001Inventors: Jeffrey W. Akers, James Michael Zerkus
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Patent number: 6237663Abstract: A metal cord for reinforcing articles made from elastomeric material comprises a plurality of metal wires wound spirally around each other. At least one of the metal wires is formed from a shape memory material, has capacities of recovering a previously memorized shape, and is deformed from the memorized shape. The shape memory wire of the cord has the recovery capacities substantially active in a first heat cycle and degraded to at least a significant predetermined extent after the first heat cycle. One or more such metal cords may be incorporated in pneumatic tires, reinforcing fabric, and other articles, including by means of processes described herein.Type: GrantFiled: October 14, 1998Date of Patent: May 29, 2001Assignee: Pirelli Coordinamento Pneumatici S.p.A.Inventors: Marco Cipparrone, Gurdev Orjela, Guido Riva
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Patent number: 6236300Abstract: The present invention provides a bistable switch using a shape memory alloy, and a method for manufacturing the same. More specifically, the bistable switch includes a substrate having at least one power source; a flexible sheet having a first distal end attached to the substrate; a bridge contact formed at a second and opposite distal end of the flexible sheet; and at least one heat activated element connected to a first surface of the flexible sheet and between the second distal end and the power source. During operation, current from the power source passing through the heat activated element to indirectly bend the flexible sheet and short the signal contacts on the substrate with a sustainable force.Type: GrantFiled: March 26, 1999Date of Patent: May 22, 2001Inventor: R. Sjhon Minners
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Patent number: 6220550Abstract: A mechanical actuating device for moving an aerodynamic or hydrodynamic surface includes at least one flexure member confined in an elastically deformed condition. The flexure member is movable against the force generated by its elastic deformation to move the device into one of a plurality of stable positions, in which the device, and therefore the aerodynamic or hydrodynamic surface, are held by the force generated by elastic deformation of the flexure member. Since the flexure member is always elastically deformed, it “snaps” between discrete, stable positions and is held firmly in each. In another embodiment more flexure members can be used to provide additional stable positions. In one application, the actuating device is used as a trailing edge tab for a helicopter or tiltrotor blade to reduce 1/rev vibrations. The device can be actuated manually or electrically using shape-memory alloy wires to snap the flexure members into their various stable positions.Type: GrantFiled: March 31, 1999Date of Patent: April 24, 2001Assignee: Continuum Dynamics, Inc.Inventor: Robert M. McKillip, Jr.
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Patent number: 6053992Abstract: A mechanism that uses the shape recovery of a shape memory alloy for sealing openings or high pressure passages. A component made of a shape memory alloy can be processed in its martensitic state to have a reduced dimension smaller than that of the opening or the passage to be sealed. Upon heating, shape recovery takes place which is associated with the reverse crystalline phase transformation of martensite. The shape recovery of the previously processed shape memory alloy component yields a diameter which is greater than that of the opening or passage to be sealed. The shape recovery provides the dimensional interference and force required for sealing.Type: GrantFiled: September 30, 1997Date of Patent: April 25, 2000Assignee: Memry CorporationInventors: Ming H. Wu, L. McD. Schetky
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Patent number: 6041728Abstract: A control tab on a submarine or the like is angularly displaced by a remote control actuator system featuring a pair of shape-memory cables consist of a superelastic actuating cable connected to the control tab and a force generating thermoelastic cable anchored to the submarine frame. A force transmitting lever interconnects the cables and is selectively locked by a releasable locking mechanism in a position holding the actuating cable fully stretched with the control tab displaced a maximum amount from its neutral position by the displacing force generated in the thermoelastic cable in response to heating thereof by electric current conducted therethrough.Type: GrantFiled: July 31, 1998Date of Patent: March 28, 2000Assignee: The United States of America as represented by the Secretary of the NavyInventors: David Goldstein, Thang Dinh Nguyen
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Patent number: 6010584Abstract: The shape memory effect is displayed by near-equiatomic ruthenium alloys of Ta or Nb with compositions of Ta.sub.x Ru.sub.1-x where x can be as low as 0.38 and preferably x=0.44 to 0.63 and Nb.sub.x Ru.sub.1-x where x can be as low as 0.25 and preferably x=0.45 to 0.59 which exhibit a transition from the high-temperature cubic phase to a tetragonal phase. These alloys are prepared by melting together tantalum and ruthenium, or niobium and ruthenium, in the above mentioned ratios. A further embodiment of this invention is to alloy NiTi alloys with, one of these two ruthenium-based high-temperature alloys (i.e. either Ta--Ru or Nb--Ru) so as to obtain a similar behavior which will result in an increase in the transition temperature relative to unalloyed Ni--Ti.Type: GrantFiled: September 30, 1997Date of Patent: January 4, 2000Assignee: The United States of America as represented by the Secretary of the NavyInventors: Richard Fonda, Roy Vandermeer, Harry Jones
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Patent number: 6001195Abstract: To remarkably improve shape memory properties without the need for strictly controlling the composition, the present invention provides a Ti--Ni-based shape-memory alloy having a titanium content within a range of from 50 to 66 atomic %, which comprises an amorphous alloy heat-treated at a temperature of from 600 to 800 K., in which sub-nanometeric precipitates generating coherent elastic strains are formed and distributed in the bcc parent phase(B2).Type: GrantFiled: December 18, 1996Date of Patent: December 14, 1999Assignee: National Research Institute for MetalsInventors: Setsuo Kajiwara, Takehiko Kikuchi, Kazuyuki Ogawa, Shuichi Miyazaki, Takeshi Matsunaga
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Patent number: 5976281Abstract: A Ni--Ti superelastic alloy demonstrates superelastic properties at normal temperatures from about 0 and 30.degree. C. The superelastic alloy allows shape alteration when the temperature is in excess of 40.degree. C. The Ni--Ti superelastic alloy is produced by plastic working a composition containing essentially Ni and Ti, and subjecting the composition to heat treatment at a temperature between 600 and 800.degree. C. to impart shape memory. When the Ni--Ti superelastic alloy is used in an eyeglass frame, it allows the shape of the pad arms to be adjusted at temperatures above about 40.degree. C.Type: GrantFiled: February 29, 1996Date of Patent: November 2, 1999Assignee: Furukawa Electric Co.Inventors: Masayuki Nakamura, Mikio Takeuchi
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Patent number: 5958159Abstract: A process for the production of a superelastic material out of a nickel and titanium alloy, characterized by the fact that it consists in obtaining an ingot starting from a mixing of nickel and titanium consisting in 55.6%.+-.0.4% in weight of nickel and to proceed with a thermal treatment of martensite plaquettes generation by subjecting said ingot during 5 to 45 minutes to a temperature comprised between 480 and 520.degree. C. The process allows the obtaining of a truly superelastic material at room temperature.Type: GrantFiled: January 9, 1998Date of Patent: September 28, 1999Assignee: Memometal IndustriesInventor: Bernard Prandi
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Patent number: 5951793Abstract: The present invention provides a Ni--Ti--Pd superelastic alloy material of a composition consisting of, by atomic percent, 34 to 49% nickel, 48 to 52% titanium and 3 to 14% palladium. Optionally, in a part of nickel and/or titanium of this alloy is replaced with one or more elements selected from a group of Cr, Fe, Co, V, Mn, B, Cu, Al, Nb, W and Zr such that these elements to be replaced amount to 2% or less in total (by atomic percent), wherein a stress hysteresis between the loading and unloading stresses in the stress-strain curve at temperatures between Af and Af+5.degree. is as small as 50 to 150 MPa. Since the Ni--Ti--Pd superelastic alloy material having the above composition is excellent in hot workability, it can be hot-worked into a wire having a diameter up to the range from 1 to 5 mm and manufactured at a low cost. Then, a final heat-treatment is given to the hot-worked material at a temperature in the range from 300 to 700.degree. C.Type: GrantFiled: July 9, 1996Date of Patent: September 14, 1999Assignee: The Furukawa Electric Co., Ltd.Inventors: Kengo Mitose, Tatsuhiko Ueki
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Patent number: 5948184Abstract: An elongated flexible housing for an atherectomy or other intracorporeal catheter which is formed of a shape memory alloy such as an alloy formed predominantly of NiTi intermetallic compound. The housing preferably has an inner chamber with a tissue cutter or other diagnostic or therapeutic system provided within the chamber to sever stenotic material which is urged into the chamber through a opening or window in the housing. In one embodiment the housing has at least one section which is relatively flexible with adjacent sections which are relatively stiff to provide an increase in the overall flexibility of the housing.Type: GrantFiled: August 22, 1997Date of Patent: September 7, 1999Assignee: Devices for Vascular Intervention, Inc.Inventors: John J. Frantzen, Sepehr Fariabi
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Patent number: 5885381Abstract: The present invention provides a Ni--Ti--Pd superelastic alloy material of a composition consisting of, by atomic percent, 34 to 49% nickel, 48 to 52% titanium and 3 to 14% palladium. Optionally, a part of nickel and/or titanium of this alloy is replaced with one or more elements selected from a group of Cr, Fe, Co, V, Mn, B, Cu, Al, Nb, W and Zr such that these elements to be replaced amount to 2% or less in total (by atomic percent), wherein a stress hysteresis between the loading and unloading stresses in the stress-strain curve at temperatures between Af and Af+5.degree. is as small as 50 to 150 MPa. Since the Ni--Ti--Pd superelastic alloy material having the above composition is excellent in hot workability, it can be hot-worked into a wire having a diameter up to the range from 1 to 5 mm and manufactured at a low cost. Then, a final heat-treatment is given to the hot-worked material at a temperature in the range from 300.degree. to 700.degree. C.Type: GrantFiled: February 24, 1998Date of Patent: March 23, 1999Assignee: The Furukawa Electric Co., Ltd.Inventors: Kengo Mitose, Tatsuhiko Ueki
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Patent number: 5863360Abstract: A method of treatment of a shape memory alloy involves shot peening of the alloy sample, thereby causing a crystal to amorphous transition of a surface layer of the sample without substantially affecting bulk characteristics of the material, particularly its shape memory behavior and biocompatibility. The method may be used for surface hardening and to reduce coefficients of friction. The method may be advantageously used for treating tissue sutures and orthodontic devices such as dental archwires.Type: GrantFiled: November 19, 1996Date of Patent: January 26, 1999Assignees: The University of Dundee, The University NottinghamInventors: John Vivian Wood, David Malcolm Grant, Sarah Margaret Green
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Patent number: 5825275Abstract: A micro-dimensioned shape memory alloy composite composed of a thin film of shape memory material and a substrate film. The substrate film does not require further processing and thus the composite can be used as a switch without removing any portion of the substrate on which the SMA is deposited. It is also shown that more effective switches can be manufactured by including as a component of the composite a stress compensating film.Type: GrantFiled: October 25, 1996Date of Patent: October 20, 1998Assignee: University of MarylandInventors: Manfred Wuttig, Quanmin Su
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Patent number: 5821664Abstract: Shape memory alloy actuators comprising at least one hollow helical spring with an array of parallel shape memory alloy wires enclosed within or parallel and attached to each of the at least one hollow helical springs. Insulative end caps are attached to end of the at least one hollow helical springs, the insulative end caps defining electrodes for conducting electricity to the arrays of parallel shape memory alloy wires. Voltage means are connected to the electrodes for selectively providing electrical energy to the parallel array of shape memory alloy wires, causing the parallel array of shape memory alloy wires to expand and contract, providing either motion or measurement functions.Type: GrantFiled: March 28, 1997Date of Patent: October 13, 1998Inventor: Moshen Shahinpoor
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Patent number: 5687958Abstract: A damping body for damping periodically alternating loads uses a shape-memory alloy material to govern the damping. The damping body is sintered from metal grains or is laminated from a plurality of perforated sheet-metal layers. The individual sheet-metal layers are orientated transversely or parallel to the loading direction and are connected to one another over the full surface area. A combination formed from a multiplicity of round pins orientated parallel to the loading direction and having enclosed gussets can also be used as a damping body. A certain hollow-space portion inside the damping body can also be created by drilling, slitting or grooving. The proportion of the open pore or bore volume of the damping body to the total volume is at least 5%, preferably about 15 to 40%.Type: GrantFiled: August 28, 1992Date of Patent: November 18, 1997Assignee: Mercedes-Benz AGInventors: Rainer Renz, Johann Kramer
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Patent number: 5641364Abstract: A method of manufacturing a high-temperature shape memory alloy includes the steps of cold-working a high-temperature shape memory alloy, in which a reverse martensite transformation start temperature (As) in a first heating after cold working reaches 350.degree. C. or above. Thereafter, the cold-worked alloy undergoes a first heat treatment for a period of time within the incubation time required for recrystallization or less, and at a temperature higher than a reverse martensite transformation finish temperature (Af). Finally, the resultant alloy is annealed with a second heat treatment, at a temperature which is not less than the plastic strain recovery temperature and not more than the recrystallization temperature. Specifically, the first heat treatment is performed for a period of three minutes or less at a temperature which exceeds 500.degree. C. and which is lower than the melting point of the alloy. The composition of the high-temperature shape memory alloy is Ti.sub.50 Ni.sub.50-x Pd.sub.Type: GrantFiled: October 27, 1995Date of Patent: June 24, 1997Assignee: The Furukawa Electric Co., Ltd.Inventors: Dmitrii Victorovich Golberg, Kazuhiro Otsuka, Tatsuhiko Ueki, Hiroshi Horikawa, Kengo Mitose
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Patent number: 5611874Abstract: A composite structure comprising a body having a surface. Cladding covers at least a part of the surface. The body and the cladding are formed of different materials, at least one of which is a shape memory alloy having a recoverable strain in excess of 1.0%.Type: GrantFiled: July 26, 1995Date of Patent: March 18, 1997Assignee: Surface Genesis, Inc.Inventors: Gholam R. Zadno-Azizi, Raj Subramaniam, Mir A. Imran