Eccentric mechanism and its application as a pump

Abstract

The aim of this project was to build an eccentric mechanism in which rotary motion obtained from a common shaft was converted into reciprocating motion. The system used to give the eccentricity was a cam. Once the mechanism was constructed, tests were carried out on it to investigate different characteristics which it possessed. In doing so, various parameters were taken into consideration, mainly those of the efficiencies at different working loads. As a result of these tests, improvements were made and eventually the efficiency was considerably improved. The second aim of the project was to give to the system a practical application, this, being its use as a horizontal reciprocating pump. To this end a piston and cylinder were built as ready-made ones could not be obtained. The pump built was a simple one, with the closing and opening valves connected externally on to the feeding pipes. To obtain the rotary motion a rotor was also constructed. This as will be explained, was a very primitive one made up of two cup-like wind collectors. An expression for the torque at given velocity was derived. This gave only an indication of the torque which must be supplied to the mechanism. When the system was completed (eccentric mechanism, pump and rotor), it was taken out into the open. Finally, it should be noted that SI units were used in all calculations carried out.