This straight line drive is not as forceful as that of No. 37. The small gear driven by crank pin in red disk, meshes with the large internal gear, thus increasing the speed. An added advantage of this motion is the great multiplication of the distance traveled by piston rod.
[Virginia Downward & William M. Clark, 1930]
[Editor’s Note: This mechanism should really be called a hypocycloid gear straight-line mechanism. When the small gear is half the diameter of the large gear, a point on the circumference of the small gear will trace a perfect straight line. Model S-16 in the Reuleaux Collection also illustrates this mathematical principle. FCM]
