Linear Compressor

Abstract

A linear compressor ( 1 ) includes a cylinder ( 21 ) with a piston ( 22 ) connected through a main spring ( 19 ) and a planar spring ( 20 ). One or more flat blocks of permanent magnet material ( 17 ) with large faces of the blocks facing a stator ( 15 ) and defining armature poles are secured to a connecting rod ( 30 ). A lateral support ( 52 ) acts between the cylind ( 21 ) and the connecting rod ( 30 ) at a location midway between the permanent magnet material and the piston ( 22 ) allowing axial movement of the connecting rod ( 30 ) but transferring side loads to the cylinder ( 21 ).

1 . A linear compressor comprising:
 a cylinder part including a cylinder bore,   a piston disposed in said bore and slidable therein,   a main spring connecting directly or indirectly said cylinder part to said piston,   a connecting member connecting between said main spring and said piston,   a stator having an air gap, said connecting member passing through said air gap, and   one or more substantially flat blocks of permanent magnet material secured to said connecting member with the large faces of said blocks facing the stator, said permanent magnet material magnetised to define at least one armature pole; and wherein said main spring comprises a combination of a plurality of individual spring elements acting in parallel.   
   
   
       2 . A linear compressor as claimed in  claim 1 , wherein the combination includes at least one planar spring element contributing higher lateral stiffness. 
   
   
       3 . A linear compressor as claimed in  claim 1 , wherein the combination includes at least one planar spring and at least one coil spring. 
   
   
       4 . A linear compressor comprising:
 a cylinder part including a cylinder bore,   a piston disposed in said bore and slidable therein,   a main spring connecting directly or indirectly said cylinder part to said piston,   a connecting member connecting between said main spring and said piston,   a stator having an air gap, said connecting member passing through said air gap, and   at least one armature pole located along said connecting member,   wherein said connecting member is supported only by said piston at one end and by said main spring away from said one end, and said main spring comprises a combination of individual spring elements acting in parallel.   
   
   
       5 . A linear compressor as claimed in  claim 4 , wherein the combination includes at least one planar spring element contributing higher lateral stiffness. 
   
   
       6 . A linear compressor as claimed in  claim 4 , wherein the combination includes at least one planar spring and at least one coil spring. 
   
   
       7 . A linear compressor comprising:
 a cylinder part including a cylinder bore,   a piston disposed in said bore and slidable therein,   a main spring connecting directly or indirectly said cylinder part to said piston, and   a connecting member connecting between said main spring and said piston, with a compliant element in said connecting member transmitting side and axial loads but allowing rotation about axes transverse to the axis of reciprocation of said piston in said bore; wherein said main spring comprises a combination of a plurality of individual spring elements acting in parallel.   
   
   
       8 . A linear compressor as claimed in  claim 7 , wherein the combination includes at least one planar spring element contributing higher lateral stiffness. 
   
   
       9 . A linear compressor as claimed in  claim 7 , wherein the combination includes at least one planar spring and at least one coil spring. 
   
   
       10 . A linear compressor comprising:
 a cylinder part including a cylinder bore,   a piston disposed in said bore and slidable therein,   a main spring connecting directly or indirectly said cylinder part to said piston,   a connecting member connecting between said main spring and said piston and connecting said main spring to said piston,   a stator having an air gap, said connecting member passing through said air gap,   one or more substantially flat blocks of permanent magnet material secured to said connecting member with the large faces of said blocks facing the stator, said permanent magnet material magnetised to define at least one armature pole, and   a lateral support acting between said cylinder part and said connecting member, at a location intermediate said permanent magnet material and said piston, said lateral support allowing axial movement of said connecting rod, but transferring side loads to said cylinder part.   
   
   
       11 . A linear compressor as claimed in  claim 10 , wherein the main spring provides lateral support acting between said cylinder part and said connecting member, at a location such that said armature pole or poles are between said main spring location and said lateral support located so that the armature of said motor is supported at one end by said main spring and at the other end by said lateral support. 
   
   
       12 . A linear compressor as described in  claim 10 , wherein said lateral support comprises one or more planar springs. 
   
   
       13 . A linear compressor as described in  claim 10 , wherein said lateral support comprises one or more sliding bearings acting on the connecting member. 
   
   
       14 . A linear compressor as claimed in  claim 10 , wherein, between the lateral support and the piston, the connecting member is laterally flexible or includes at least one flexible portion, so as to effectively transmit axial forces but to have lateral and angular compliance of the piston relative to the axis and line of reciprocation of the connecting member. 
   
   
       15 . (canceled)