Agustin de Betancourt’s plunger lock: Approach to its geometric modeling with Autodesk Inventor Professional

A geometric modeling of Agustin de Betancourt’s plunger lock with the parametric Autodesk Inventor Professional 2016 software has been obtained, which has made it possible to get a simulation of movement, as well as perspectives and exploded views. The process of geometric modeling has followed several steps: First, the only available mapping has been only a couple of unscaled sheets found in several documents. These are accompanied by a report on which parts of the plunger are detailed, the dimensions of some parts and the purpose of the joint, allowing a first approach to the reconstruction of the plunger lock as conceived by Betancourt. Also, some dimensional hypothesis that the engineer does not specify while considering the design has been done, such as transmitting motion to the shaft which gives the counterweight raising and lowering the diver and the dimensions of shafts and gears (with the gearing for transmitting the motion of the crank shaft of the counterweight). The main contribution is that for the first time the sub-system of the counterweight (gears, pulleys, girder bridge, chains, mobile counterweight and tilting counterweights) has been dimensioned to always achieve the equilibrium position between the movable counterweight and the plunger, independent of the part which is outside the water. This unprecedented research values one of Betancourt´s main contributions to civil engineering which provided a real solution to the problems of navigation canals of the French rivers in the early nineteenth century and was highly valued by the French Academy of Sciences.