Movement No. 115 demonstrates a balanced dual-pinion and double-rack mechanism that converts rotary motion into rectilinear motion with perfectly equal force and velocity on both sides. Two toothed wheels of identical size are positioned on opposite sides of a double rack — one engaging the top face and the other engaging the bottom face of the rack. Both pinions rotate simultaneously, each driving its respective rack surface. Because the two wheels are equal in size, they impart exactly the same force and velocity to each side of the rack, ensuring that the rack moves in a straight line without any tendency to twist, bind, or rack sideways. This balanced arrangement is particularly valuable in applications requiring precise, wobble-free linear motion under load, such as in heavy-duty presses, lifting platforms, and precision linear guides where symmetric force distribution is critical.
115. Rotary motion of the toothed wheels produces rectilinear motion of the double rack and gives equal force and velocity to each side, both wheels being of equal size.