Integrated stirling refrigerator

Abstract

An integrated Stirling refrigerator includes an eccentric shaft box defining a sealed cavity therein filled with a gas medium; an eccentric shaft provided rotatably around a rotation axis within the sealed cavity and including an eccentric segment and a non-eccentric segment; a stator assembly provided around the rotation axis and fixed within the sealing cavity; a rotor assembly arranged on the non-eccentric segment about the rotation axis, with an air gap formed between the stator assembly and the rotor assembly along the axial direction; a compression link assembly arranged within the sealed cavity and coupled to the eccentric segment; and an expansion link assembly arranged within the sealed cavity and coupled to the eccentric segment. The stator assembly and the rotor assembly form an axial flux motor arranged in the axial direction and configured to drive the eccentric shaft to rotate about the rotation axis through the rotor assembly.

What is claimed is: 
     
         1 . An integrated Stirling refrigerator, comprising:
 an eccentric shaft box defining therein a sealed cavity filled with a gas medium;   an eccentric shaft provided rotatably around a rotation axis within the sealed cavity and comprising an eccentric segment with its center line offset from the rotation axis and a non-eccentric segment with its center line coinciding with the rotation axis;   a stator assembly provided around the rotation axis and fixed within the sealed cavity;   a rotor assembly provided on the non-eccentric segment around the rotation axis, with an air gap formed between the rotor assembly and the stator assembly along an axial direction;   a compression link assembly provided within the sealed cavity and coupled to the eccentric segment; and   an expansion link assembly provided within the sealed cavity and coupled to the eccentric segment;   wherein the stator assembly and the rotor assembly form an axial flux motor arranged in the axial direction and configured to drive the eccentric shaft to rotate about the rotation axis through the rotor assembly.   
     
     
         2 . The integrated Stirling refrigerator according to  claim 1 , wherein the eccentric shaft box comprises a housing and an end plate, the housing having an opening and the end plate being sealingly connected to the opening. 
     
     
         3 . The integrated Stirling refrigerator according to  claim 2 , wherein the opening in the housing is circular in shape, and the end plate is in a shape of a circular plate matching the shape of the opening. 
     
     
         4 . The integrated Stirling refrigerator according to  claim 2 , wherein the housing and the end plate are made of aluminum alloy, and the end plate and the housing are connected by a sealing ring or are sealingly welded. 
     
     
         5 . The integrated Stirling refrigerator according to  claim 2 , wherein two ends of the eccentric shaft are connected to one bearing fixed to the housing and another bearing fixed to the end plate, respectively. 
     
     
         6 . The integrated Stirling refrigerator according to  claim 2 , wherein one end of the eccentric shaft is connected to an inner ring of a deep groove ball bearing fixed inside the housing, and another end thereof is connected to an inner ring of a thrust ball bearing fixed to an inner side of the end plate. 
     
     
         7 . The integrated Stirling refrigerator according to  claim 6 , wherein the stator assembly is fixed to the inner side of the end plate and is coaxially provided with respect to the thrust ball bearing. 
     
     
         8 . The integrated Stirling refrigerator according to  claim 5 , wherein motor lead pins protrude from an outer side of the end plate, and the motor lead pins extend through the end plate in the axial direction and are electrically isolated from the end plate through insulation sintering. 
     
     
         9 . The integrated Stirling refrigerator according to  claim 1 , wherein the stator assembly comprises a stator core and a winding; the stator core is provided with a bottom portion perpendicular to the axial direction, a plurality of teeth protruding from the bottom portion in the axial direction towards the rotor assembly; the winding comprises a plurality of coils, each of which is arranged around and electrically isolated from a corresponding one of the teeth;
 the rotor assembly comprises a rotor disk and a plurality of permanent magnets; the rotor disk is mounted around the non-eccentric segment, the permanent magnets are fixed on a side of the rotor disk facing towards the stator assembly, and the permanent magnets are magnetized in the axial direction, with each two circumferentially adjacent permanent magnets having opposite polarities therebetween.   
     
     
         10 . The integrated Stirling refrigerator according to  claim 9 , wherein the air gap between the rotor assembly and the stator assembly is 0.2 mm. 
     
     
         11 . An integrated Stirling refrigerator, comprising:
 a housing configured to be a hollow structure and having an opening on one side thereof;   an end plate sealingly connected to the housing to close the opening, with a sealed cavity formed between the housing and the end plate;   an eccentric shaft rotatably arranged in the sealed cavity, the eccentric shaft defining a rotation axis, and comprising an eccentric segment and a non-eccentric segment arranged along the rotation axis, the eccentric segment configured to be drivingly connected with a compression link assembly and an expansion link assembly;   an axial flux motor configured to drive the eccentric shaft to rotate about the rotation axis, the axial flux motor comprising:
 a stator assembly fixedly mounted to an inner side of the end plate; and 
 a rotor assembly mounted on the non-eccentric segment for rotation with the non-eccentric segment, with an air gap formed between the rotor assembly and the stator assembly along an axial direction of the axial flux motor. 
   
     
     
         12 . The integrated Stirling refrigerator according to  claim 11 , wherein the eccentric shaft has opposite two ends along the rotation axis, one end of the eccentric shaft is connected to one bearing fixed to the housing, and the other end of the eccentric shaft is connected to another bearing fixed to the inner side of the end plate. 
     
     
         13 . The integrated Stirling refrigerator according to  claim 12 , wherein the stator assembly is fixed to the inner side of the end plate and is coaxially provided with respect to the another bearing. 
     
     
         14 . The integrated Stirling refrigerator according to  claim 12 , wherein the one bearing is a deep groove ball bearing. 
     
     
         15 . The integrated Stirling refrigerator according to  claim 12 , wherein the another bearing is a thrust ball bearing. 
     
     
         16 . The integrated Stirling refrigerator according to  claim 11 , wherein motor lead pins extend through the end plate and configured for supplying power to the axial flux motor, and the motor lead pins are electrically isolated from the end plate through insulation sintering. 
     
     
         17 . The integrated Stirling refrigerator according to  claim 11 , wherein the stator assembly comprises a stator core and a winding, the stator core comprises a bottom portion fixed to the inner side of the end plate, and a plurality of teeth protruding from the bottom portion in the axial direction towards the rotor assembly, and the winding is arranged around the teeth;
 the rotor assembly comprises a rotor disk and a plurality of permanent magnets; the rotor disk is mounted around the non-eccentric segment, the permanent magnets are fixed on a side of the rotor disk facing towards the stator assembly and spaced apart from each other along a circumferential direction of the rotor disk, and the permanent magnets are magnetized in the axial direction, with each two circumferentially adjacent permanent magnets having opposite polarities therebetween.   
     
     
         18 . The integrated Stirling refrigerator according to  claim 11 , wherein the air gap between the rotor assembly and the stator assembly is 0.2 mm.