Patent ID: 8491281

Claim:
A compressor comprising: a housing comprising a stationary coil assembly; a moving assembly comprising one or more magnets and configured to compress a gas within a compression volume; a guide rod connected to the moving assembly which reciprocates axially with the moving assembly; and a bellows seal positioned between the moving assembly and the housing, the bellows seal defining the compression volume, wherein the moving assembly is configured to reciprocally move between a top-stroke position and a bottom-stroke position while each time passing through a mid-stroke position, in which the moving assembly is in substantial alignment with the stationary coil assembly, wherein the moving assembly moves from the mid-stroke position to each respective top-stroke and bottom-stroke position due to forces generated by the stationary coil assembly, the moving assembly forming an enlarged gap between the one or more magnets and the stationary coil assembly that is larger, while in the top-stroke position and the bottom-stroke position, relative to a nominal gap formed while in the mid-stroke position, and wherein the stationary coil assembly generates a force that biases the moving assembly toward the mid-stroke position from each respective top-stroke and bottom-stroke position.