Wedge-surface friction wheel 1 rotates about fixed axis A and its wedged external surface a contacts grooved external surface b of grooved friction wheel 2 which rotates about fixed axis B. The transmission ratio between wheels 1 and 2 without slippage is i₁₂=-(n₁/n₂)=-(R₂/R₁) where n₁ and n₂ are the speeds (in rpm) of wheels 1 and 2 and R₁ and R₂ are the mean radii of the wedge surfaces in contact on wheels 1 and 2. Rotation is transmitted between wheels 1 and 2 by friction between surfaces of contact a and b. The torque M₁ on driving wheel 1 is related to torque M₂ transmitted to wheel 2 by the equation Q≥(M₁x*sin(α))/(fR₁)=(M₂x*sin(α))/(fR₂) where Q is the normal force applied between the wheels (along line AB), x=1.5 to 2 is the traction assurance factor, f is the coefficient of sliding friction between surfaces a and b, and α is the angle shown. The force Q exerted between the wheels is varied by means of link 3 which is connected by turning pair B to wheel 2 and by a sliding pair to slider 4. Slider 4 turns about axis A. Screw device 5 regulates force Q by moving slider 4 along slot d of link 3.
$3362$SmF,3L$