Magnetic mixer
AssigneeMagnetic Mixers, Inc.
InventorDaniel F. Quigg
Life of this patent
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Abstract
An improved magnetic mixer includes an agitator that includes a plurality of agitator magnets. A bearing arrangement allows the agitator to be magnetically levitated along the outer surface of a cylindrical vessel fitting located within a mixing vessel. The same magnetic force that is used to levitate the mixer drives the agitator. The magnetic force is preferably generated by a plurality of magnets which rotate within an aperture extending into the vessel fitting. By magnetically levitating the agitator, there is no thrust generated by the agitator against the vessel fitting which eliminates the need for thrust bearings and reduces the overall frictional forces. The low friction results in reduced particle generation, reduced power consumption and reduced maintenance compared to conventional magnetic mixers.
Claims21
A mixer for agitating a fluid in a vessel, the mixer comprising:
- a vessel fitting having inner and outer surfaces for defining a generally cylindrical member extending into the vessel and having a longitudinal axis such that the outer surface of the vessel fitting is located within the vessel;
- an agitator comprising:
- a hub for fitting over the outer surface of the vessel fitting and rotatable with respect to the vessel fitting;
- a plurality of agitator magnets disposed circumferentially about the hub;
- means extending from the hub for agitating the fluid;
- and
- a first pair of inwardly facing bearing surfaces spaced from one another on the hub;
- a pair of bearing rings having a second pair of bearing surfaces for cooperating with the first pair of bearing surfaces, the pair of bearing rings for encircling the outer surface of the vessel fitting and able to move longitudinally along a portion of the outer surface of the vessel fitting;
- and
- driving means within the vessel fitting for magnetically coacting with the plurality of agitator magnets and causing the agitator to spin about the longitudinal axis within the vessel and levitate along the outer surface of the vessel fitting.
A mixer for agitating a fluid in a vessel, the mixer comprising:
- a vessel fitting having inner and outer surfaces for defining a generally cylindrical member extending into the vessel and having a longitudinal axis such that the outer surface of the vessel fitting is located within the vessel;
- an agitator comprising:
- a hub for fitting over the outer surface of the vessel fitting and rotatable with respect to the vessel fitting, the hub having a top and a bottom;
- a plurality of agitator magnets sealed within and spaced circumferentially about the agitator;
- means for agitating the fluid;
- a first bearing surface located toward the top of the agitator and above the hub magnets;
- and
- a second bearing surface located toward the bottom of the hub and below the hub magnets;
- first and second bearing rings with corresponding third and fourth bearing surfaces for cooperating with the first and second bearing surfaces, the first and second bearing rings being in longitudinal sliding engagement with a portion of the outer surface of the vessel fitting;
- and
- a plurality of drive magnets rotatably mounted within the vessel fitting for rotating about the longitudinal axis in order to create a rotating magnetic field for engaging the plurality of agitator magnets and causing the agitator to spin about the longitudinal axis within the vessel and for magnetically levitating the agitator along the vessel fitting.
A system for mixing a fluid comprising:
- a vessel having a bottom wall, the bottom wall defining a hollow and generally cylindrical drive housing extending into the vessel along an imaginary rotational axis, the drive housing having inner and outer surfaces, the outer surface being within the vessel;
- first and second bearing rings having corresponding first and second bearing surfaces, the bearing rings being slidably mounted within the vessel on the outer surface of the drive housing;
- an agitator comprising:
- a hollow cylindrical hub for fitting over and in rotatable engagement with the outer surface of the drive housing;
- a plurality of agitator magnets spaced circumferentially about the hub;
- one or more agitator blades extending radially from the hub;
- and
- third and fourth bearing surfaces for engaging the first and second bearing surfaces, respectively;
- and
- a driver within the drive housing for creating a rotating magnetic field about the rotational axis for engaging the agitator magnets and thereby rotating the agitator, and levitating the agitator along the outer surface of the drive housing.
Dependencies are inferred from the claim text.