Patents by Inventor Kari M Ullakko

Kari M Ullakko has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Method for producing motion and force by controlling the twin structure orientation of a material and its uses
    Patent number: 6747377
    Abstract: The present invention refers to a method for obtaining shape changes, motion and/or force in a material having a twinned structure. According to the method, a sufficiently high external magnetic field applied to the material reorients the twin structure thereby producing motion/force. The operation is possible if the magnetocrystalline anisotropy energy is higher than or comparable to the energy of the reorientation of the twin structure to produce a certain strain.
    Type: Grant
    Filed: April 19, 2002
    Date of Patent: June 8, 2004
    Inventor: Kari M. Ullakko
  • Actuators and apparatus
    Patent number: 6515382
    Abstract: The present invention relates to actuators, linear motors and rotational motors based on magnetic-field-induced strains taking place in the actuator material. These strains are caused by the reorientation of the twin structure of the actuator materials by the applied magnetic field.
    Type: Grant
    Filed: November 3, 1999
    Date of Patent: February 4, 2003
    Inventor: Kari M Ullakko
  • Method for producing motion and force by controlling the twin structure orientation of a material and its uses
    Patent number: 6157101
    Abstract: The present invention refers to a method for obtaining shape changes, motion and/or force in a material having a twinned structure. According to the method, a sufficiently high external magnetic field applied to the material reorients the twin structure thereby producing motion/force. The operation is possible if the magnetocrystalline anisotropy energy is higher than or comparable to the energy of the reorientation of the twin structure to produce a certain strain.
    Type: Grant
    Filed: January 12, 1998
    Date of Patent: December 5, 2000
    Inventor: Kari M. Ullakko
  • High-strain, magnetic field-controlled actuator materials
    Patent number: 5958154
    Abstract: Magnetically-controlled actuator materials are provided that produce large actuation stroke, that exhibit fast actuation response time and corresponding high-frequency operation, and that enable efficient actuation energy conversion at convenient operating temperatures. The actuator materials exhibit an austenitic crystal structure above a characteristic phase transformation temperature and exhibit a martensitic twinned crystal structure below the phase transformation temperature. One actuator material provided by the invention is an alloy composition that can be defined generally as (Ni.sub.a Fe.sub.b Co.sub.c).sub.65-x-y (Mn.sub.d Fe.sub.e Co.sub.f).sub.20+x (Ga.sub.g Si.sub.h Al.sub.i).sub.15+y, where x is between about 3 atomic % and about 15 atomic % and y is between about 3 atomic % and about 12 atomic %, and where a+b+c=1, where d+e+f=1, and g+h+i=1.
    Type: Grant
    Filed: August 18, 1997
    Date of Patent: September 28, 1999
    Assignee: Massachusetts Institute of Technology
    Inventors: Robert C. O'Handley, Kari M. Ullakko