A reciprocating surroundings compressor is a positive displacement compressor that uses a crankshaft-driven piston and cylinder to compress the air. … A two-stage compressor contains an additional step where the atmosphere is compressed by another, smaller sized piston to a pressure as high as 175 PSI.
Like a small internal combustion engine, a conventional piston compressor has a crankshaft, a connecting rod and piston, a cylinder and a valve head. … As the piston moves down, a vacuum is Piston Air Compressor created above it. This allows outside atmosphere at atmospheric pressure to press open up the inlet valve and fill up the area above the piston.