It  resembles a roller bearing, but instead of cylindrical rollers, non-revolving  asymmetric figure-eight shaped sprags are used. When the unit rotates in one  direction the rollers slip or free-wheel, but when a torque is applied in the  opposite direction, the rollers tilt slightly, producing a wedging action and  binding because of friction.
  
                              The scope of  applications for one-way clutches covers a wide spectrum from small office  machines to heavy machinery and long conveyors. 
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