Method for centering reciprocating bodies and structures manufactured therewith

Abstract

Methods for assembling a reciprocating body, such as a piston, within a bore using a design are described. The piston is substantially centered within the bore and then connected at one end through a rotational coupling to a substantially laterally fixed structure connected to the bore such that during normal operation the piston can rotate within the bore along the bore axis of symmetry but can no longer move laterally. Before fixing the rotational coupling, the piston is connected to an external gas source and substantially aligned along the bore axis of symmetry by a gas bearing having one or more gas bearing ports disposed toward the bore. During normal operation, the gas bearing provides a rotational force sufficient to realize a non-frictional bearing between the piston and the bore. The method of assembly is particularly useful in the assembly of Stirling cycle cryocooler comprising a piston, a compressor bore, adapted to contain the piston, a gas inlet to the piston, a plurality of gas bearing ports located within the piston and disposed toward the compressor bore, the gas inlet being in fluid communication with the gas bearing ports, a rotational coupling structure attached to one end of the piston, and a substantially laterally fixed structure affixed to the compressor bore and the rotational coupling structure.