'No dead centre' Steam Engine, 1887

Model of a two-cylinder Vertical Engine with triangular connecting rod. This type of 'no dead centre' engine was built by John Musgrave & Sons of Bolton, based upon a patent of 1887.

This engine was designed so that it will alwyas be able to start, regardless of the position it has previously stopped in. Two cylinders, arranged side by side, have a common connecting-rod in the form of a triangle, the apex of which encloses the pin of the overhanging crank. The two other corners of the triangle are, by very short links, connected respectively with the two piston-rods, the crossheads of which slide in ordinary guides. From the middle of the top of the triangle two bridle-rods couple the connecting-rod to a stationary centre on the side of the framing, and so restrict the movement and close the chain. The valves are in the form of cylindrical slides, and receive their motion from a common eccentric. The example has 3 in. cylinders, with 4 in. stroke, and is intended to run at 300 r.p.m., when it will indicate about 3 h.p.