Patent ID: 7038565
Filing Date: 2006-05-02
Classification: F25B,H01F,Y02B

Abstract:
1. A magnet assembly comprising: a first stationary magnet subassembly and a second stationary magnet subassembly, each stationary magnet subassembly including at least one permanent magnet section having a north end and a south end, a north concave section magnetically coupled to the north end of the permanent magnet section and including a north pole face, and a south concave section magnetically coupled to the south end of the permanent magnet section and including a south pole face opposite the north pole face in a flux direction across an air gap; a first rotating subassembly adapted to rotate about a first rotational axis to a first plurality of rotational positions and including at least one permanent magnet section having a north end and a south end, a north rounded end cap magnetically coupled to the north end of the permanent magnet section, and a south rounded end cap magnetically coupled to the south end of the permanent magnet section, wherein the rounded end caps of the first rotating subassembly are adapted to intermittently nest with the north concave sections of the first and second stationary magnetic assemblies as the first rotating subassembly rotates, a second rotating subassembly adapted to rotate about a second rotational axis to a second plurality of rotational positions and including a first rounded end cap and a second rounded end cap connected together by a magnetically permeable section, wherein the rounded end caps of the second rotating subassembly are adapted to intermittently nest with the south concave sections of the first and second stationary magnetic assemblies as the second rotating subassembly rotates, wherein when the first rotating subassembly is at a first rotational position and the second rotating subassembly is at a second rotational position, the north rounded end cap of the first rotating subassembly nests with the north concave section of the first stationary magnet subassembly, the south rounded end cap of the first rotating subassembly nests with the north concave section of the second stationary magnet subassembly, the first rounded end cap of the second rotating subassembly nests with the south concave section of the first stationary magnet subassembly, and the second rounded end cap of the second rotating subassembly nests with the south concave section of the second stationary magnet subassembly, whereby the air gap of the first stationary magnet subassembly is subjected to a relatively high magnetic field and the air gap of the second stationary magnet subassembly is subjected to a relatively low magnetic field; and wherein when the first rotating subassembly is at a third rotational position and the second rotating subassembly is at a fourth rotational position, the north rounded end cap of the first rotating subassembly nests with the north concave section of the second stationary magnet subassembly, the south rounded end cap of the first rotating subassembly nests with the north concave section of the first stationary magnet subassembly, the first rounded end cap of the second rotating subassembly nests with the south concave section of the second stationary magnet subassembly, and the second rounded end cap of the second rotating subassembly nests with the south concave section of the first stationary magnet subassembly, whereby the air gap of the second stationary magnet subassembly is subjected to a relatively high magnetic field and the air gap of the first stationary magnet subassembly is subjected to a relatively low magnetic field.