Patent ID: 7728707

Claim:
A magnet arrangement for producing a magnetic field in a direction of a z axis in a working volume located on the z axis about z=0, the arrangement comprising: a first container disposed about the z-axis; a second container disposed about the z-axis at an axial separation from said first container to define a split; a first coil system disposed in said first container, said first coil system having a first coil section comprising a first coil body and a first winding package and a second coil section comprising a second coil body and a second winding package; a second coil system disposed in said second container, said second coil system having a third coil section comprising a third coil body and a third winding package, wherein said first and said third coil sections are exposed to attractive magnetic forces acting in an axial direction towards said split and said second coil section is exposed to repulsive magnetic forces acting in the axial direction away from the split, said magnetic forces being at least partially mechanically transmitted to said first and said second containers; a first mechanical structure disposed in said split to withstand compressive loads and to support at least part of said attractive magnetic forces; and a second mechanical structure disposed radially within said split within dimensions of said first and said second containers to mechanically withstand tensile loads in a z-direction and to at least partially support said repulsive magnetic forces acting in said axial direction, said second mechanical structure connected to and holding together said first and said second containers.