gearbox mounted compressor

[Lang]

Sylvian

The bottom part of the compressor is just the drive from the gearbox with a crankshaft, connecting rod and piston (just like a car engine)

The air section all happens on top of the piston, like a car. As the piston goes down it draws air in through a one way valve. As the piston goes up again that valve closes and the air is squeezed out a second one way valve into an air tank or air hose.

The round hole in the bottom of the cover is to drain the oil, it needs a plug.

The big opening in the cover is there because, when the piston goes up and down, the volume of the crankcase changes. If you put your hand over it when it is running you will feel air going in when the piston goes up and blowing out when it goes down. When it is running fast at normal speed this will just be a continuous pulsing. This air vent is what makes most of the "choof-choof-choof" compressor noise.

Lang

Here is a drawing.