Compressed-gas-operated reciprocating-piston devices

A compressed-gas-operated reciprocating piston device, which includes a composite cylinder component comprising a rigid inner metal cylinder tube in which the piston reciprocates in use and an outer sleeve moulded of polymerized plastics material and surrounding and bonded to the metal cylinder tube, the sleeve overlying the entire outer circumferential surface of the major part of the length of the tube, and the sleeve being formed on its outer surface with a plurality of longitudinally-extending outwardly-projecting integrally-moulded ribs spaced apart around the circumference of the sleeve, the device further including an outer tubular muffler made of polymerized plastics material which surrounds the ribbed sleeve and defines within the muffler a chamber referred to as the muffler chamber, which communicates with an exhaust opening leading out of the muffler into the ambient atmosphere, the cylinder component being formed with at least one gas discharge port in its wall which opens into the muffler chamber between two adjacent ribs of the sleeve, and in which a longitudinally-extending elongate moulded passage is formed in the interior of at least one of the ribs, and passage constituting a transfer passage for supplying compressed gas to one end portion of the interior of the cylinder tube.