圆上泽文大学 Involute Profile(渐开线齿廓) The line(string)is always tangent to the basic circle. The center of curvature of the involute is always at the point of PK tangency of the string with the B cylinder. A tangency to the involute is then always normal to the string, the length of which is the instantaneous radius of curvature(曲率半径)of the involute curve BK=Pk There is no involute curve within the base circle. 圆上泽夫道大学 Involute Profile ▣Conclusion: KiK2=Kik2 ▣Why? K BK=BA 1313  The line(string) is always tangent to the basic circle.  The center of curvature of the involute is always at the point of tangency of the string with the cylinder.  A tangency to the involute is then always normal to the string, the length of which is the instantaneous radius of curvature(曲率半径) of the involute curve  There is no involute curve within the base circle. K B A K BK =  Involute Profile（渐开线齿廓）  Conclusion:  Why? K1 K2 K1' K2' B B' A1 A2 Involute Profile 1 2 , 2 , K1 K  K K BK = BA