Multi-stage compressor with annular ring valve service

Claim 1

IN COMBINATION A COMPRESSOR INCLUDING A CASING, PARTITION MEANS DIVIDING THE CASING INTO A FIRST AND SECOND COMPARTMENT, A FIRST AND SECOND COMPRESSION MEANS IN THE CASING AND A PORTION OF EACH OF SAID FIRST AND SECOND COMPRESSION MEANS DISPOSED IN THE FIRST COMPARTMENT, EACH OF SAID FIRST AND SECOND COMPRESSION MEANS INCLUDING MEANS FORMING A CYLINDER, AN INLET AND AN OUTLET DISPOSED IN COMMUNICATION WITH THE CYLINDERS OF EACH OF SAID FIRST AND SECOND COMPRESSION MEANS, SAID INLETS OF EACH OF THE COMPRESSION MEANS COMMUNICATING WITH THE FIRST COMPARTMENT AND THE OUTLETS OF EACH OF THE COMPRESSION MEANS CONNECTED TO THE SECOND COMPARTMENT; WITH MEANS FOR CONVERTING SAID COMPRESSOR TO MULTI-STAGE OPERATION WHEREIN THE MEANS FORMING SAID CYLINDER OF SAID SECOND COMPRESSION MEANS COMPRISES A LINER HAVING A PASSAGE MEANS COMMUNICATING SAID CYLINDER WITH THE INLET OF SAID SECOND COMPRESSION MEANS, MEANS MOUNTED ON SAID SECOND COMPRESSION MEANS TO PRECLUDE COMMUNICATION BETWEEN THE INLET OF SAID SECOND COMPRESSION MEANS AND THE FIRST COMPARTMENT, CONVERSION MEANS MOUNTED TO SAID CASING RELATIVE THE INLET OF SAID SECOND COMPRESSION MEANS AND CONNECTING THE INLET THEREOF WITH THE SECOND COMPARTMENT, SAID SECOND COMPRESSION MEANS FORMING A HIGH PRESSURE STAGE, MEANS FORMING A DISCHARGE COMPARTMENT CONNECTED TO SAID SECOND COMPRESSION MEANS, AND SAID OUTLET OF THE COMPRESSION MEANS FORMING SAID HIGH PRESSURE STAGE COMMUNICATING WITH SAID DISCHARGE COMPARTMENT.