Paul & Paul
Compressor assembly
 A reciprocating piston assembly for a compressor is disclosed in that a piston with at least one groove formed in its outer surface is slidably mounted in a cylinder bore and at least one piston ring made of polymers of fluorine-containing olefin monomers, the outer diameter of said piston ring being smaller than the diameter of said cylinder bore prior to operation of the compressor but said piston ring being in contact with the inner wall defining said cylinder bore during operation of the compressor. 
Kabushiki Kaisha Toyoda Jidoshokki Seisakusho
F F F F
F05C F16J F04B F04B
additional inventional inventional inventional
Shozo Mitsuhiro Kimio
Nakayama Hattori Kato