Patent ID: 7588424

Claim:
A linear compressor unit, comprising: an electromagnetic alternating field surrounding at least a portion of a cylinder; a magnet located in said electromagnetic alternating field in said cylinder, said magnet displaceable back and forth in said electromagnetic alternating field; a piston located in said electromagnetic alternating field in said cylinder drivingly connected to said magnet; a buffer volume; a module casing which encloses said cylinder and said buffer volume; said cylinder mounted in said module casing so that said cylinder can oscillate in said module casing; said module casing including an inlet passage for media to be compressed; said cylinder including an inlet opening lying opposite said inlet passage without making contact therewith; a passage to said buffer volume formed between said inlet opening and said inlet passage; and at least one sound restrictor element located in said buffer volume passage, said sound restrictor element including a plurality of generally cylindrical walls, with a first group of walls attached to said module casing and a second group of walls attached to said cylinder for generally reciprocal relative motion between said first group of walls and said second group of walls with said first group of walls being intermeshed with said second group of walls, said first group of walls and said second group of walls forming a pathway, the pathway having a first run and a second run, the first run of the pathway extending from said passage to said buffer volume to a first change of direction portion communicating the first run with the second run with one surface of said first group of walls delimiting one side of the first run of the pathway and one surface of said second group of walls delimiting an opposite side of the first run of the pathway and the second run extending from the first change of direction portion to a second change of direction portion with another surface of said first group of walls delimiting one side of the second run of the pathway and another surface of said second group of walls delimiting an opposite side of the second run of the pathway, the pathway guiding media to be compressed that enters the pathway via said passage, moves in a first direction along the first run of the pathway, undergoes a change in direction while passing through the first change of direction portion, moves in a second direction along the second run of the pathway, and thereafter undergoes another change in direction while passing through the second change of direction portion.