A random collection of Compressed Air Engine videos

This engine uses a valve of my own design to emulate a 4 stroke action, much like an internal combustion engine. However, this engine runs on Air. The intake valve is a standard poppet valve like an automobile engine uses. However, instead of a cam actuated exhaust valve, the engine uses a sliding piston in the head. When the intake valve is closed, a spring pushes the piston valve right and allows air out (and in) of the cylinder through the exhaust port. When the intake valve opens, the incoming pressurized air pushes the sliding piston to the left, closing the exhaust port and directing the input air to the cylinder where it pushes the piston down. A cam, which runs at 1/2 the speed of the crankshaft, admits air for a power stroke every other revolution of the crankshaft. The flywheels are about 3" in diameter, the bore is 3/4" and the stroke about an inch.

This is a video of a simple, model oscillating radial air engine I built in 2007. In this video I am running this self-starting engine with an air compressor. The plans for this engine came from McCabe's model engine website ( http://npmccabe.tripod.com/steam.htm). I made a slight modification by using ball bearings and an outer bearing to make the crankshaft more stable. The cylinders are steel, and the pistons are brass rod. Each cylinder has one hole at the end of the bore for the inlet and exhaust port. The three manifold pieces are drilled for inlet and exhaust passage of the air from the compressor. It is routed as you can see from the manifold block at the back where the airline comes in. The flywheel was machined and mounted on a rotary table to mill the spokes. The engine has very little output power because it runs on less than 10psi air pressure. This engine was a fun build, but it isn't an efficient style engine.

This is my Robinson Hot air engine displayed at an engine rally on 18th of march 2007, This engine was made around 1880 and is around 128 years old. Thanks for watching

Replica engine built in my workshop from my own castings.