Linear compressor for a domestic appliance and domestic refrigeration appliance

Abstract

A linear compressor for a domestic appliance has a piston that can move in the longitudinal direction of a cylinder between top and bottom dead center positions. A piston outer surface can be contactlessly supported against a corresponding cylinder inner surface owing to the formation of a gas thrust bearing in the radial direction of the cylinder. The piston outer surface and the cylinder inner surface each have a martensitic structure in specified regions. There is also provided a domestic refrigeration appliance with a refrigerant circuit and a compressor.

1 - 8 . (canceled) 
     
     
         9 . A linear compressor for a household appliance, comprising:
 a cylinder having a cylinder inner surface and defining a longitudinal direction and a radial direction;   a piston movably disposed in the longitudinal direction of said cylinder between upper and lower dead-center positions;   said piston having an outer surface to be supported in the radial direction of said cylinder in a contactless manner opposite a corresponding cylinder inner surface by way of a gas pressure bearing; and   said piston outer surface and said cylinder inner surface having a martensitic microstructure at least in predetermined regions thereof.   
     
     
         10 . The linear compressor according to  claim 9 , wherein each of said piston outer surface and said cylinder inner surface has a single said predefined region at a location where contact between said piston outer surface and said cylinder inner surface is possible, when no gas pressure bearing is embodied or when a pressure of said gas pressure bearing has fallen below a predetermined pressure threshold. 
     
     
         11 . The linear compressor according to  claim 9 , wherein said cylinder comprises a bushing forming said cylinder inner surface. 
     
     
         12 . The linear compressor according to  claim 9 , wherein said predetermined regions are formed of X15T.N steel. 
     
     
         13 . The linear compressor according to  claim 9 , wherein said microstructures of said predetermined regions in each case comprise homogeneously distributed, spherical carbides. 
     
     
         14 . The linear compressor according to  claim 13 , wherein said carbides have a diameter of 1 to 2 μm. 
     
     
         15 . The linear compressor according to  claim 9 , wherein said predetermined regions are heat-treated, surface-hardened and/or press-hardened. 
     
     
         16 . A household refrigeration appliance, comprising a refrigeration circuit and a compressor, said compressor being a linear compressor according to  claim 9 .