Magnetic seal for magnetically-responsive devices, systems, and methods
AssigneeLord Corporation
InventorsMichael Jarzomski, Askari Badre-Alam, Luca Di Deco
Life of this patent
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Abstract
A magnetically-responsive device (100) having a magnetic seal (160,170) to retain magnetically responsive material within a defined space (150) is provided. The magnetically-responsive device (100) has a shaft (110), a rotor (130), a magnetic field generator (145), a magnetically-responsive medium and a magnetic seal (160,170). The seal (160,170) is preferably a non-contact seal (160,170) that does not deteriorate over time and generates little to no resistance.
Claims20
A magnetically-responsive device contained within a housing, the device comprising:
- a shaft;
- a rotor comprised of a highly magnetically permeable material, the rotor being interconnected to the shaft to restrain relative rotation therebetween;
- a magnetic field generator separated from the rotor by a void, the magnetic field generator having an electromagnet stator;
- a magnetically-responsive powder contained within and at least partially filling the void, wherein the magnetic field generator is controllable to cause the magnetically-responsive powder to align along the flux path within the void and thereby cause a change in torsional resistance of the rotor;
- and
- a magnetic seal positioned proximate the shaft, the magnetic seal comprising a magnetic element configured to generate a magnetic field to prevent passage of the magnetically-responsive powder out of the void, wherein the magnetic seal comprises a magnetic concentrator configured to concentrate magnetic flux to align magnetically-responsive medium in an area serving as a powder barrier, and wherein the magnetic concentrator comprises one or more non-magnetic spacers positioned on a side of the magnetic element.
A magnetically-responsive device comprising a magnetic seal configured to be positioned at or near a rotatable shaft, the magnetic seal including a magnetic element configured to generate a magnetic field to prevent passage of magnetically-responsive powder along a rotatable shaft;
- wherein the magnetic seal comprises a magnetic concentrator configured to concentrate magnetic flux to align magnetically-responsive medium in area serving as a powder barrier;
- and
- wherein the magnetic concentrator comprises a non-magnetic spacer positioned on a side of the magnetic element.
A method for preventing passage of a magnetically-responsive powder out of a magnetically-responsive device, the method comprising:
- positioning a magnetic seal at or near a rotating shaft associated with the magnetically-responsive device;
- generating a magnetic field to prevent passage of the magnetically-responsive powder along the shaft away from the magnetically-responsive device;
- and
- coupling a magnetic concentrator to the magnetic seal, the magnetic concentrator being configured to concentrate magnetic flux to align magnetically-responsive medium in area serving as powder barrier;
- wherein the coupling of the magnetic concentrator to the magnetic seal includes positioning a non-magnetic spacer on a side of the magnetic element.
Dependencies are inferred from the claim text.