Method and apparatus for mixing liquid solutions using a rotating magnet to generate a stirring vortex action

• US 6,382,827 B1
• Filed: 11/01/2000
• Issued: 05/07/2002
• Est. Priority Date: 11/01/2000
• Status: Expired due to Term

• Current Assignee: Siemens Healthcare Diagnostics Incorporated (Siemens AG)
• Original Assignee: Dade Behring, Inc. (Siemens AG)
• Inventors: Gebrian, Peter Louis
• Primary Examiner(s): Cooley, Charles E.
• Application Number:
  US09/703,139
• Time in Patent Office: 552 Days
• Field of Search: 366/273, 366/274, 366/348, 416/3, 422/99, 435/302.1
• US Class Current: 366/274
• CPC Class Codes: B01F 2101/23 Mixing of laboratory samples e.g. in preparation of analysing or testing properties of materials
• CPC Class Codes: B01F 33/452 using independent floating stirring elements

Abstract

A method for rapidly mixing a liquid solution in a sample container by causing a small magnetic mixing member to rapidly revolve or orbit the container'"'"'s axis within the solution in a generally circular pattern in response to a revolving magnetic field positioned in close proximity to the sample container.

Claims

1. A method for mixing a liquid solution, the method comprising:

providing a container having a bottom with the liquid solution therein;

freely disposing a spherical ferromagnetic mixing member within the container; and

,

revolving a U-shaped, L-shaped or cup-shaped bracket having an upper arm portion in a circular pattern around the outside of and in close proximity to the container, the bracket having and a permanent or semi-permanent magnet for generating magnetic forces attached to the upper arm portion, the magnet and the upper arm portion being disposed distance above the bottom of the container,

so that magnetic forces acting upon the mixing member cause the mixing member to revolve said distance above the bottom of the container, thereby generating a mixing motion within the liquid solution.

2. The method of claim 1 wherein the mixing member is made of an iron alloy and has a diameter in the range 2-6 mm.

3. The method of claim 1 wherein the mixing member has a protective coating to prevent contamination thereon, the coating having thickness about 25 microns.

4. A method for mixing a liquid solution, the method comprising:

providing a container having a bottom with the liquid solution therein;

freely disposing a spherical ferromagnetic mixing member within the container; and

,

supporting the container with a rack;

transporting the rack proximate a magnetec field;

revolving the magnetic field in a circular pattern outside of and in close proximity to the container;

so that magnetic forces acting upon the mixing member cause it to revolve within the container thereby generating a mixing motion within the liquid solution.

5. The method of claim 4 wherein the mixing member is made of an iron alloy and has a diameter in the range 2-6 mm.

6. The method of claim 4 wherein the mixing member has a protective coating to prevent contamination thereon, the coating having thickness about 25 microns.

7. An apparatus for mixing a liquid solution contained in a liquid container, the apparatus comprising:

a container having a bottom with the liquid solution therein;

a spherical ferromagnetic mixing member freely disposed within the container;

a permanent or semi-permanent magnet; and

,

means for revolving a U-shaped, L-shaped or cup-shaped bracket in a circular pattern around the outside of and in close proximity to the liquid container, the bracket having an upper arm portion with the permanent or semi-permanent magnet attached to the upper arm portion, the magnet and the upper arm portion being disposed a distance above the bottom of the container,

so that magnetic forces acting upon the mixing member cause it to revolve said distance above the bottom of the container and generate a mixing motion within the liquid solution.

8. The apparatus of claim 7 wherein the mixing member is made of an iron alloy and has a diameter in the range 2-6 mm.

9. The apparatus of claim 7 wherein the mixing member has a protective coating to prevent contamination thereon, the coating having thickness about 25 microns.