Patent ID: 8381607

Claim:
A roller screw, comprising: a plurality of rollers, each said roller comprising a radial surface in a cylindrical shape; a long shaft shaped like a long bar, said long shaft comprising a cylindrical peripheral surface and a V-channel spirally extending around said cylindrical peripheral surface, said V-channel comprising two opposing sidewalls defining a first track face and a second track face and a contained angle between said first track face and said second track face which substantially equal to 90°; a screw nut module, said screw nut module comprising a turnover passage, a turnaround passage and an axial hole for the passing of said long shaft, an internal surface surrounding said axial hole and a V-groove spirally extending around said internal surface corresponding to said V-channel of said long shaft, said V-groove comprising two opposing sidewalls defining a first contact face and a second contact face and a contained angle between said first contact face and said second contact face which substantially equal to 90°; wherein said V-channel and said V-groove constitute a load path for accommodating said rollers; said turnover passage divides said load path into a first load path and a second load path, said first load path and said second load path each having one end thereof respectively connected to one end of said turnover passage and an opposite end thereof respectively connected to two distal ends of said turnaround passage; said turnover passage extends over the cylindrical peripheral surface of said long shaft; wherein said rollers are movable in an order through said first load path into said turnaround passage and then into said second load path and then into said turnover passage and then back to said first load path; wherein the radial surface of each said roller is kept in contact with said first track face and said first contact face when each said roller enters said first load path; the radial surface of each said roller is kept in contact with said second track face and said second contact face when each said roller enters said second load path.