Patent ID: 8613350

Claim:
An anti-rotation mechanism incorporated in a wrench, said mechanism comprising: a first race having a cylindrical surface and an axis of rotation; a second race having a plurality of protrusions, said plurality of protrusions spaced regularly around said second race, said first race inside said second race, said axis of rotation of said first race coaxial with a center axis of said second race; a plurality of pairs of rollers, each one of said plurality of pairs of rollers having a first roller and a second roller, a corresponding one of said plurality of protrusions positioned between said first roller and said second roller; a plurality of springs, each one of said plurality of springs between adjacent pairs of said plurality of pairs of rollers, said plurality of springs biasing said plurality of first and second rollers toward said corresponding one of said plurality of protrusions; and a plurality of positioning members, each one of said plurality of positioning members adjacent a peak of a corresponding one of said protrusions, said plurality of positioning members movable in tandem to a first position in which each of said first rollers is positioned away from said corresponding protrusion wherein said second rollers inhibit motion of said first race relative to said second race in a first direction, said plurality of positioning members movable to a second position in which each of said second rollers is positioned away from said corresponding protrusion wherein said first rollers inhibit motion of said first race relative to said second race in a second direction that is opposite to said first direction, and wherein each one of said plurality of protrusions is defined by a first surface and a second surface joined at said peak, said first roller engaging said first surface and said second roller engaging said second surface, said peak being a rounded surface, each one of said first and second surfaces being concave and defined by a first radius, said first radius having a center proximate a corresponding one of said protrusions and within a space defined between said first race and said second race.