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"The large driving cone J is hollow, the smaller or driven one convex. The latter presses, when desired, against the ineer surface of the former; its speed depends upon its position with regard to the axis of the driver. When its axis is in line with that of the driver, it has the same speed; the further it is drawn laterally therefrom, the greater the speed." —Grimshaw, 1902

Friction Coupling for Various Speed Adjustment

"The large driving cone J is hollow, the smaller or driven one convex. The latter presses, when desired,…