Permanent magnet device

• US 8,310,325 B2
• Filed: 01/30/2012
• Issued: 11/13/2012
• Est. Priority Date: 10/04/2007
• Status: Active Grant

• Current Assignee: Hussmann Corporation (Panasonic Holdings Corporation)
• Original Assignee: Hussmann Corporation (Panasonic Holdings Corporation)
• Inventors: Zhang, Ming, Madireddi, Sesha
• Primary Examiner(s): Musleh, Mohamad
• Application Number:
  US13/361,417
• Publication Number:
  US 20120126922A1
• Time in Patent Office: 288 Days
• Field of Search: 335/219, 335284-285, 335/296, 335/297, 335302-306, 62/31
• US Class Current: 335/306
• CPC Class Codes: F25B 21/00 Machines, plants or systems, using electric or magnetic effects
• CPC Class Codes: F25B 2321/0023 with modulation, influencing or enhancing an existing magnetic field
• CPC Class Codes: H01F 7/0205 Magnetic circuits with PM in general
• CPC Class Codes: H01F 7/021 Construction of PM H01F7/0278 takes precedence; PM compositions H01F1/032
• CPC Class Codes: H01F 7/0273 Magnetic circuits with PM for magnetic field generation
• CPC Class Codes: Y02B 30/00 Energy efficient heating, ventilation or air conditioning [HVAC]

Abstract

A magnet arrangement for creating a magnetic field. The magnet arrangement includes a first magnet having a first surface defining a first pole and a second surface defining a second pole opposite the first pole, and a second magnet having a third surface defining a third pole and a fourth surface defining a fourth pole opposite the third pole. The second surface has a higher magnetic flux density than the first surface. The third surface has a higher magnetic flux density than the fourth surface. The second magnet is spaced from the first magnet to define a first gap between the second surface and the third surface. Magnetic field lines of the magnetic field run from the first surface to the second surface, from the second surface to the third surface through the first gap, and from the third surface to the fourth surface.

Claims

1. A magnet arrangement for creating a magnetic field, comprising:

a first magnet having a first surface defining a first pole and a second surface defining a second pole opposite the first pole, wherein the second surface has a higher magnetic flux density than the first surface;

a second magnet having a third surface defining a third pole and a fourth surface defining a fourth pole opposite the third pole, wherein the third surface has a higher magnetic flux density than the fourth surface, wherein the second magnet is spaced from the first magnet to define a first gap between the second surface and the third surface, and wherein magnetic field lines of the magnetic field run from the first surface to the second surface, from the second surface to the third surface through the first gap, and from the third surface to the fourth surface;

a third magnet spaced from the second magnet and having a fifth surface defining a fifth pole and a sixth surface defining a sixth pole opposite the fifth pole, wherein the sixth surface has a higher magnetic flux density than the fifth surface, and wherein the magnetic field lines run from the fourth surface to the fifth surface and from the fifth surface to the sixth surface;

a fourth magnet spaced from the third magnet and having a seventh surface defining a seventh pole and an eighth surface defining an eighth pole opposite the seventh pole, wherein the seventh surface has a higher magnetic flux density than the eighth surface, wherein the fourth magnet is spaced from the third magnet to define a second gap between the sixth surface and the seventh surface, and wherein the magnetic field lines run from the sixth surface to the seventh surface through the second gap, and from the seventh surface to the eighth surface;

wherein the magnetic field converges through the first magnet, then passes through the first gap, then diverges through the second magnet, then converges through the third magnet, then passes through the second gap, then diverges through the fourth magnet and then returns from the fourth magnet to the first magnet.

2. The magnet arrangement of claim 1, wherein the magnetic flux density in the gap is larger than the magnetic flux density of the first surface.

3. The magnet arrangement of claim 1, wherein the magnetic flux density in the second gap is larger than the magnetic flux density of the eighth surface.

4. The magnet arrangement of claim 1, further comprising a first magnetically permeable element disposed between the second magnet and the third magnet to create a path for the magnetic field lines to run from the fourth surface to the fifth surface through the first magnetically permeable element.

5. The magnet arrangement of claim 4, further comprising a second magnetically permeable element disposed adjacent the first surface and the eighth surface to create a path for the magnetic field lines to run from the first surface to the eighth surface through the second magnetically permeable element.

6. The magnet arrangement of claim 5, wherein the first magnetically permeable element includes a cylindrical tube.

7. The magnet arrangement of claim 6, wherein the second magnetically permeable element includes a cylindrical tube that is larger in diameter than the first magnetically permeable element.

8. The magnet arrangement of claim 1, wherein the second surface has less surface area than the first surface.

9. The magnet arrangement of claim 1, further comprising a magnetocaloric material disposed in the first gap.

10. The magnet arrangement of claim 1, wherein the first magnet is formed of a plurality of magnet segments, wherein at least one of the magnet segments includes a portion of the first surface and a portion of the second surface, wherein each of the magnet segments includes parallel magnetic field lines, and wherein the first magnet includes non-parallel magnetic field lines.

11. The magnet arrangement of claim 1, wherein the second surface is arcuate and the third surface is arcuate, and wherein the second surface and the third surface share a common arc center.

12. A magnet arrangement, comprising:

a first magnet having a first generally arc-shaped cross section;

a second magnet spaced from the first magnet to define a first gap between the first magnet and the second magnet, the second magnet having a second generally arc-shaped cross section;

a third magnet having a third generally arc-shaped cross section; and

a fourth magnet spaced from the third magnet to define a second gap between the third magnet and the fourth magnet, the fourth magnet having a fourth generally arc-shaped cross section;

wherein the first and second generally arc-shaped cross sections share a common arc center;

wherein the first magnet and the second magnet create a magnetic field including magnetic field lines that converge in the first magnet, run through the first gap between the first and second magnets, and diverge in the second magnet;

wherein the first gap is remote from the arc center;

wherein the third magnet and the fourth magnet contribute to the magnetic field including magnetic field lines that run from the second magnet to the third magnet, converge in the third magnet, run through the second gap, and diverge in the fourth magnet; and

wherein the second gap is remote from the arc center and wherein the arc center is substantially between the first gap and the second gap.

13. The magnet arrangement of claim 12, further comprising magnetocaloric material disposed in the first gap and in the second gap.

14. The magnet arrangement of claim 12, further comprising magnetocaloric material disposed in the first gap.

15. The magnet arrangement of claim 14, wherein the surface areas of the poles of the first magnet decrease in the direction of the magnetic field lines and the surface areas of the poles of the second magnet increase in the direction of the magnetic field lines.