Patent ID: 7768160

Claim:
An electromagnetic motor comprising: a stator having: a non-ferrous tube of a selected axial length having a first end and a second end; first and second stator magnetic flux producing elements surrounding said tube and spaced apart from each other a first axial distance with each of said first and second stator elements on an opposite side of a selected point on said tube between said first and second ends of said tube closest to, and spaced apart from, a correspondingly numbered end of said tube with each of said first and second stator magnetic flux producing elements disposed to direct a magnetic flux axially within said tube in the direction of said first and second ends within said tube; and a third stator magnetic flux producing element surrounding said tube spaced apart a second axial distance from a closest side of said first stator magnetic flux producing element toward said first end of said tube wherein said second axial distance is greater than said first axial distance with said third stator magnetic flux producing element providing magnetic flux axially along the axis of the tube of a selected polarity; a fourth stator magnetic flux producing element surrounding said tube spaced apart a third axial distance from a closest side of said second stator magnetic flux producing element toward said second end of said tube wherein said third axial distance is greater than said first axial distance with said fourth stator magnetic flux producing element providing magnetic flux axially along the axis of the tube of the same selected polarity as said third stator magnetic flux producing element; and a slider disposed to move axially within said tube between said first and second ends, said slider includes a slider magnetic flux producing element having a first and a second side and a width with respect to the axis of the tube that is substantially equal to said first axial distance with said slider magnetic flux producing element providing magnetic flux axially along the axis of the tube of an opposite polarity to said selected polarity of said third and fourth stator magnetic flux producing elements; wherein an at rest position of said slider magnetic flux producing element is substantially centered relative to a center of the first axial distance between said first and second stator magnetic flux producing elements.