Patent Publication Number: US-2023151801-A1

Title: Linear compressor

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is a divisional of U.S. application Ser. No. 16/591,191, filed on Oct. 2, 2019, which claims priority under 35 U.S.C. 119 and 35 U.S.C. 365 to Korean Patent Application No. 10-2019-0039150, filed on Apr. 3, 2019, which are hereby incorporated by reference in their entirety. 
    
    
     BACKGROUND 
     The present invention relates to a linear compressor. 
     In a reciprocating type compressor, a compression space for compressing working gas is formed between a piston and a cylinder, and the piston linearly reciprocates within the cylinder to compress refrigerant flowing into the compression space. 
     In recent years, among the reciprocating type compressors, in particular, the piston is directly connected to a driving motor which reciprocates linearly, so that the compression efficiency can be improved without mechanical loss occurring when the rotational motion of a motor is converted into linear motion, many linear compressors having simple structure are developed. 
     Generally, a linear compressor is configured to suction and compress refrigerant, and then discharge the refrigerant, while a piston is linearly reciprocated within a cylinder by a linear motor in a closed shell. 
     Related Art Korean Patent Laid-Open Publication No. 10-2016-0011009 (Jan. 29, 2016) discloses a linear compressor. Such a linear compressor of the related art has the following problems. 
     First, since the spring is provided in the space between a supporter and a stator cover and in the space between the supporter and a back cover, a plurality of springs have to be installed and thus there is a problem that the volume of the compressor due to the plurality of springs is increased. 
     Second, since both end portions of the plurality of springs have to be installed on the supporter, the stator cover, and the back cover, the fixing portions for fixing the plurality of springs are increased and complicated. Therefore, there is a problem that the possibility that the fixed portion of the spring of the compressor between the driving is broken or separated becomes higher. 
     SUMMARY 
     The present invention has been made in order to solve the above problems and an objective of the present invention is to provide a linear compressor capable of high-speed operation by supporting a repeated load of a movable portion by using a spring assembly composed of a plurality of spring parts. 
     In addition, an objective of the present invention is to provide a linear compressor capable of preventing the spring parts from being broken or separated in a process of the reciprocating motion of the movable part by fixing both side portions of the plurality of spring parts to the outer surfaces of the supporter and the rear cover. 
     In addition, an objective of the present invention is to provide a linear compressor capable of fixing in an axial direction and a radial direction of the supporter and the rear cover to easily support an axial force and a side force occurring between the driving of the compressor. 
     In addition, an objective of the present invention is to provide a miniaturized linear compressor which reduces the volume of the spring assembly and thus reduce the size of a shell of the compressor by disposing one spring assembly composed of the plurality of spring parts between the supporter and the rear cover. 
     The linear compressor according to an embodiment of the present invention includes one spring assembly composed of a plurality of spring parts and the one spring assembly is fixed to both side surfaces of a supporter and a rear cover and can easily support a load generated in the compressor. 
     In addition, both side portions of the spring part are provided with fixing brackets coupled to the supporter and the rear cover, and the fixing bracket is provided with an insertion member or a bracket coupling member so that the coupling force of the spring part can be increased. 
     In particular, the insertion member is provided so as to be capable of being in contact with the spring part, so that the spring part can be prevented from moving in a lateral direction or a radial direction. 
     In addition, since the bracket coupling member is coupled to the two ribs forming the insertion portion of the spring part, the spring part can be tightened in a state of being inserted into the fixing bracket. 
     The linear compressor according to an embodiment of the present invention includes a supporter for supporting a piston reciprocating in a frontward and rearward direction; a rear cover spaced apart from the supporter; and a spring assembly disposed between the supporter and the rear cover and thus the supporter and the rear cover can be elastically supported. 
     The spring assembly may include a plurality of spring parts each having a first side portion supported by the supporter and a second side portion supported by the rear cover, and can be supported at a plurality of points of the supporter and the rear cover. 
     The spring assembly may further include a fixing bracket which forms a spring insertion portion into which the first side portion or the second side portion is inserted and coupled to the supporter and the rear cover. 
     The fixing bracket may include a first fixing bracket configured to support the first side portions of the plurality of spring parts, the first bracket being configured to be coupled to the supporter; and a second fixing bracket configured to support the second side portions of the plurality of spring parts, the second fixing bracket being configured to be coupled to the rear cover. 
     The fixing bracket may include a bracket main body on which the spring insertion portion is formed; and a body coupling portion which is provided on both sides of the bracket main body and to which a coupling member is fastened. 
     The coupling member may include a first coupling member which is fastened to the supporter and the body coupling portion; and a second coupling member which is fastened to the rear cover and the body coupling portion. 
     The linear compressor may further include an insertion hole which is formed on the bracket main body; and an insertion member which is inserted into the insertion hole and is in contact with the first side portion or the second side portion of the spring part. 
     The insertion hole may include a first insertion hole which is formed to be recessed in an axial direction of the bracket main body and communicates with the spring insertion portion. 
     A first direction in which the spring insertion portion is recessed from an outer surface of the bracket main body may intersect with a second direction in which the first insertion hole is recessed from the outer surface of the bracket main body. 
     The insertion hole includes a plurality of the first insertion holes. 
     The insertion member may include a first insertion member inserted into the first insertion hole, and the first insertion member may extend in a normal direction of the spring part inserted into the spring insertion portion. 
     The plurality of insertion holes may further include a second insertion hole which is recessed from the bracket main body in a radial direction and communicates with the spring insertion portion, and a third direction in which the second insertion hole is recessed from the outer surface of the bracket main body may intersect with the first direction and the second direction, respectively. 
     The insertion member may include a second insertion member which is inserted into the second insertion hole, and the second insertion member may extend in a normal direction of the spring part inserted into the spring insertion portion. 
     The plurality of spring parts may include a first spring part, a second spring part, and a third spring part which are respectively supported at three points on the supporter and the rear cover. 
     The bracket main body may include first and second ribs extending from the spring insertion portion and spaced apart from each other; and a bracket coupling member configured to be fastened to the first and second ribs. 
     The supporter may include a plate-shaped supporter main body and a supporter recessed portion which is recessed from an outer surface of the supporter main body, and the bracket main body may further include a support part located in the supporter recessed portion. 
     The support part, the spring insertion portion, and the first and second ribs may be aligned in the axial direction. 
     According to the above configuration, the linear compressor can be operated at a high speed by supporting the repeated loads of the movable portion by using the spring assembly composed of a plurality of spring parts. 
     In addition, by fixing both side portions of the plurality of spring parts to the outer surfaces of the supporter and the rear cover, it is possible to prevent breakage or separation of the spring parts in a process of reciprocating motion of the movable part. 
     In addition, the spring assembly can be fixed in the axial direction and the radial direction of the supporter and the rear cover to easily support an axial force and a side force occurring between the driving of the compressor. 
     In addition, since one spring assembly composed of the plurality of spring parts is disposed between the supporter and the rear cover, the volume of the spring assembly can be reduced, and accordingly, the size of the shell of the compressor can be reduced to realize miniaturization of the linear compressor. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a conceptual diagram illustrating a linear compressor according to an embodiment of the present invention. 
         FIG.  2    is a sectional view illustrating a linear compressor according to a first embodiment of the present invention. 
         FIG.  3    is a perspective view illustrating a state where the spring assembly according to the first embodiment of the present invention is coupled to a supporter and a rear cover. 
         FIG.  4    is an exploded perspective view illustrating a spring assembly, a supporter, and a rear cover according to a first embodiment of the present invention. 
         FIG.  5    is a front view illustrating a configuration of a spring part and a fixing bracket constituting the spring assembly according to the first embodiment of the present invention. 
         FIG.  6    is an exploded perspective view illustrating the spring part and the fixing bracket. 
         FIG.  7    is a sectional view taken along line  7 - 7 ′ of  FIG.  3   . 
         FIG.  8    is a perspective view illustrating a state where a spring assembly according to a second embodiment of the present invention is coupled to a supporter and a rear cover. 
         FIG.  9    is a perspective view illustrating a configuration of a spring part and a fixing bracket constituting a spring assembly according to a second embodiment of the present invention. 
         FIG.  10    is a front view illustrating a configuration of a spring part and a fixing bracket constituting a spring assembly according to a second embodiment of the present invention. 
         FIG.  11    is a sectional view taken along line  11 - 11 ′ of  FIG.  8   . 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that, in adding reference numerals to the constituent elements of the drawings, the same constituent elements are denoted by the same reference symbols as possible even if they are illustrated in different drawings. In addition, in the description of the embodiments of the present invention, the detailed description of related known configurations or functions will be omitted in a case where it is determined that a detailed description of related known configurations or functions hinders understanding of the embodiments of the present invention. 
     Also, in the description of embodiments, terms such as first, second, A, B, (a), (b) or the like may be used herein when describing components of the present invention. Each of these terminologies is not used to define an essence, order or sequence of a corresponding component but used merely to distinguish the corresponding component from other component(s). It should be noted that if it is described in the specification that one component is “connected,” “coupled” or “joined” to another component, the former may be directly “connected,” “coupled,” and “joined” to the latter or “connected”, “coupled”, and “joined” to the latter via another component. 
       FIG.  1    is a conceptual diagram illustrating a linear compressor according to an embodiment of the present invention. 
     Referring to  FIG.  1   , the linear compressor  10  according to an embodiment of the present invention includes a motor M for generating a driving force, a piston P 1  coupled to the motor M and reciprocating in a frontward and rearward direction, a movable portion P having a supporter P 2  to be coupled to the piston P 1 , and a support portion S for supporting the movable portion P. The support portion S may be supported in a shell of the compressor. 
     The support portion S includes a rear cover S 1  forming a support main body and a spring S 2  provided between the piston P 1  and the rear cover S 1 . The spring S 2  supports a reciprocating piston P 1  in the axial direction and can be configured to limit movement of the piston P 1  in the lateral direction (the radial direction). 
     At both side portions of the spring S 2 , the fixing portion to be coupled to the rear cover S 1  and the supporter P 2  may be provided. In order to prevent the spring S 2  from being separated from the rear cover S 1  and the supporter P 2  in a process in which the piston P 1  reciprocates in the axial direction, the fixing portion of the spring S 2  has to be firmly coupled to the rear cover S 1  and the supporter P 2 . In this embodiment, the fixing structure with respect to the rear cover S 1  of the spring S 2  and the supporter P 2  is proposed. 
       FIG.  2    is a sectional view illustrating a linear compressor according to a first embodiment of the present invention. 
     Referring to  FIG.  2   , the linear compressor  10  according to the first embodiment of the present invention includes a compressor main body provided inside a shell (not illustrated). 
     The compressor main body includes a frame  22 , a cylinder  23  inserted into the frame  22  and having a compression space C, a piston  30  linearly reciprocating in the cylinder  23 , and a motor  20  for applying a driving force to the piston  30 . The motor  20  may include a linear motor which linearly reciprocates the piston  30  in an axial direction. The motor  20  has a hollow cylindrical shape, and the cylinder  23  can be inserted into the motor  20 . 
     The linear compressor  10  further includes a suction muffler  50 . The suction muffler  50  is coupled to the piston  30  and suctioned into the inside of the shell so that the refrigerant passing through the shell bracket  85  can flow there-into. A portion of the suction muffler  50  is located within the piston  30 . Ina process in which the refrigerant passes through the suction muffler  50 , the flow noise thereof is reduced and the refrigerant passing through the suction muffler  50  can flow into the piston  30 . 
     The directions are defined. The “axial direction” is a direction in which the piston  130  reciprocates and, among the axial direction, a direction from the suction muffler  50  toward the compression space C, that is, a direction in which the refrigerant flows, is referred to as “frontward direction”; and the opposite direction thereto is defined as “rearward direction”. When the piston  130  moves in the frontward direction, the compression space C can be compressed. The direction perpendicular to the “axial direction” can be defined as “radial direction”. 
     Meanwhile, a discharge cover  25  may be provided in front of the compression space P to form a discharge space for the refrigerant discharged from the compression space P. 
     The linear compressor  10  further includes a stator cover  40  coupled to the front of the motor  20 . The stator cover  40  is provided with a cover body  41  having an opening through which the piston  30  can pass and at least one cover leg  45  extending from the cover body  41  toward the rear cover  70 . A plurality of the cover legs  45  are disposed in a circumferential direction and can be fastened to the rear cover  70 . 
     The linear compressor  10  further includes a supporter  60  for supporting a rear end portion of the piston  30 . The supporter  60  is coupled to the rear side of the piston  30  and may have a supporter opening  62  (see  FIG.  3   ) through which the suction muffler  50  passes. 
     The linear compressor  10  further includes a substantially disc-like rear cover  70 . To the rear cover  70 , a body support devices  80  and  85  for supporting the rear portion of the compressor main body to the shell may be coupled. In detail, the main body support devices  80  and  85  include a support spring  80  formed of a circular leaf spring and a shell bracket  85  coupled to a central portion of the support spring  80 . 
     A cover hole  82  through which the fastening member fastened to the rear cover  70  passes is formed on the support spring  80 . A plurality of the cover holes  82  may be formed on the peripheral portion of the support spring. 
     The shell bracket  85  is coupled to the shell, and the refrigerant suctioned into the shell can flow into a side of the suction muffler  50  through the inner space of the shell bracket  85 . 
     The linear compressor  10  further includes a spring assembly  100  coupled to the supporter  60  and the rear cover  70  to support the piston  30 . The spring assembly  100  is firmly fixed to the supporter  60  and the rear cover  70  so that tension or compression deformation can be performed. 
     The supporter  60  reciprocates together with the piston  30  and the rear cover  70  is a fixed component for supporting the piston  30  and the supporter  60 , and in a process of the high-speed operation of the linear compressor  10 , the spring assembly  100  has to be prevented from separating from the rear cover  70  or the supporter  60 . Hereinafter, the configuration of the spring assembly  100  will be described. 
       FIG.  3    is a perspective view illustrating a state where the spring assembly according to the first embodiment of the present invention is coupled to a supporter and a rear cover,  FIG.  4    is an exploded perspective view illustrating a spring assembly, a supporter, and a rear cover according to a first embodiment of the present invention,  FIG.  5    is a front view illustrating a configuration of a spring part and a fixing bracket constituting the spring assembly according to the first embodiment of the present invention, and  FIG.  6    is an exploded perspective view illustrating the spring part and the fixing bracket. 
     Referring to  FIGS.  3  to  6   , the spring assembly  100  according to the first embodiment of the present invention may be configured to elastically support the reciprocating piston  30  by connecting the supporter  60  and the rear cover  70 . 
     The spring assembly  100  includes a plurality of spring parts  110 ,  120 , and  130 . The plurality of spring parts  110 ,  120 , and  130  may be coupled to the supporter  60  and the rear cover  70 , respectively. It can be understood that the plurality of spring parts  110 ,  120 , and  130  constitute a spring strand of the coil spring so that one coil spring can be formed when the plurality of spring parts  110 ,  120 , and  130  are combined. 
     One side portion of the plurality of spring parts  110 ,  120 , and  130  may be coupled in the circumferential direction of the supporter  60  and the other side portion thereof may be coupled in the circumferential direction of the rear cover  70 . 
     For example, the plurality of spring parts  110 ,  120 , and  130  may include three spring parts, and the three spring parts may be coupled to three portions of the supporter  60  and three portions of the rear cover  70 . In other words, the spring assembly  100  can be supported at three points on the supporter  60  and the rear cover  70 . 
     The plurality of spring parts  110 ,  120 , and  130  include the first spring part  110 , the second spring part  120 , and the third spring part  130 . The first to third spring parts  110 ,  120 , and  130  may be configured to have a shape bent at least twice. 
     For example, the first spring part  110  includes a first bending portion  112  (see  FIG.  5   ) and a second bending portion  114  which realize a twisted shape of the coil spring. The first spring part  110  can constitute a portion of one coil spring while connecting the supporter  60  and the rear cover  70  spaced apart in the frontward and rearward direction by the first and second bending portions  112  and  114 . 
     The supporter  60  includes a supporter body  61  having a substantial disc shape and a bracket coupling portion  64  which extends from the supporter body  61  in the radial direction and to which the fixing bracket  200  is coupled. The fixing bracket  200  may be fastened to the bracket coupling portion  64  by a first coupling member  65 . The first coupling member  65  may include a screw or a rivet. 
     A plurality of bracket coupling portions  64  are provided and the plurality of bracket coupling portions  64  may be disposed in a circumferential direction. For example, six bracket coupling portions  64  may be provided, and a supporter recessed portion  67  in which the bracket main body  210  of the fixing bracket  200  is located can be formed between the two bracket coupling portions  64 . Therefore, three supporter recessed portions  67  are formed, and three bracket main bodies  210  can be located on the three supporter recessed portions  67 . 
     A supporter opening  62  into which the suction muffler  50  is inserted is formed on the supporter body  61 . For example, the supporter opening  62  may be formed in a circular shape at the central portion of the supporter body  61 . 
     The supporter body  61  is formed with a supporter groove  63  recessed rearward from the front surface of the supporter body  61 . The supporter grooves  63  may be rounded in the circumferential direction of the supporter body  61 . A plurality of the supporter grooves  63  may be formed, and the plurality of supporter grooves  63  may be spaced apart from each other and arranged in the circumferential direction. 
     The supporter body  61  is formed with a piston fastening hole  66  through which a fastening member fastened to the piston  30  passes. A plurality of the piston fastening holes  66  may be formed, and the plurality of piston fastening holes  66  may be spaced apart in the circumferential direction. 
     The rear cover  70  includes a cover body  71  having a substantial disc shape and forming a cover opening  72 . The cover opening  72  is formed in a substantially central portion of the cover body  71 , and the shell bracket  85  may be configured to be coupled. 
     The cover body  71  is formed with a spring hole  73  to be coupled with the cover hole  82  of the support spring  80 . The spring holes  73  may have a shape corresponding to the cover holes  82  and a plurality of spring holes  73  may be arranged in the circumferential direction of the cover body  71 . The fastening member may pass through the cover hole  82  and be fastened to the spring hole  73 . 
     The cover body  71  is formed with a leg hole  74  to be coupled with the cover leg  45  of the stator cover  40 . The leg hole  74  may be disposed at a side of the spring hole  73  in the circumferential direction. 
     The rear cover  70  is provided with a cover recessed portion  76  which is recessed from the outer circumferential surface of the cover body  71  in the radial direction. The bracket main body  210  of the fixing bracket  200  may be positioned on the cover recessed portion  76 . For example, three cover recessed portions  76  may be spaced apart in the circumferential direction. Three bracket main bodies  210  may be located on the three cover recessed portions  76 . 
     A second coupling member  75  may be fastened to the cover body  71 . The second coupling member  75  may be coupled to the fixing bracket  200  through the cover body  71 . The plurality of second coupling members  75  are arranged in the circumferential direction of the cover body  71  and can be coupled with the body coupling portions  220  of the fixing brackets  200 . The second coupling member  75  may include a screw or a rivet. 
     For example, six second coupling members  75  may be provided, and two second coupling members  75  may be coupled to the body coupling portion  220  in a pair. Accordingly, three fixing brackets  200  can be coupled to the cover body  71 . The two second coupling members  75  forming a pair can be disposed on both sides of the cover recessed portion  76 . 
     The spring assembly  100  includes three spring parts  110 ,  120 , and  130  and a fixing bracket  200  provided on both side portions of the three spring parts  110 ,  120 , and  130 . 
     The fixing bracket  200  includes a first fixing bracket  200   a  (see  FIGS.  5  and  6   ) provided on the first side portion  100   a  of the three spring parts  110 ,  120 , and  130  and coupled to the supporter  60 , and a second fixing bracket  200   b  (see  FIGS.  5  and  6   ) provided on the second side portion  100   b  of the three spring parts  110 ,  120 , and  130  and coupled to the rear cover  70 . The first and second fixing brackets  200   a  and  200   b  may have the same configuration. 
     Specifically, the fixing bracket  200  includes a bracket main body  210  into which the spring parts  110 ,  120 , and  130  are inserted and body coupling portions  220  which is provided on both sides of the bracket main body  210  and coupled to the supporter body  61  and the cover body  71 . 
     The bracket main body  210  is formed with a spring insertion portion  213  into which one side portion of the spring parts  110 ,  120 , and  130  is inserted. The spring insertion portion  213  includes a groove or a hole formed to be recessed from one surface of the bracket main body  210  in the radial direction. 
     The bracket main body  210  is formed with a plurality of insertion holes  215   a ,  215   b , and  215   c  into which the insertion members  251 ,  253 , and  255  are inserted. The insertion members  251 ,  253 , and  255  may be provided so as to be capable of being in contact with the spring parts  110 ,  120 , and  130  inserted into the spring insertion portion  213 . 
     In detail, the plurality of insertion holes  215   a ,  215   b , and  215   c  include first insertion holes  215   a  and  215   b  which are formed to be recessed in the axial direction of the bracket main body  210 . The first insertion holes  215   a  and  215   b  may be configured to communicate with the spring insertion portion  213 . A plurality of first insertion holes  215   a  and  215   b , for example, two first insertion holes may be formed. 
     The first direction in which the spring insertion portion  213  is recessed from the outer surface of the bracket main body  210  can intersect with a second direction in which the first insertion holes  215   a  and  215   b  are recessed from the outer surface of the bracket main body  210 . For example, the first and second directions may be perpendicular to each other. 
     The insertion members  251 ,  253 , and  255  include first insertion members  251  and  253  inserted into the first insertion holes  215   a  and  215   b . The first insertion members  251  and  253  may be, for example, columnar pieces. In addition, a plurality of first insertion members  251  and  253 , for example, two first insertion members may be provided. 
     The first insertion members  251  and  253  extend in a normal direction of the spring part inserted into the spring insertion portion  213  and can be in contact with the surface of the spring part. For example, the first insertion members  251  and  253  can press the spring parts. 
     The plurality of insertion holes  215   a ,  215   b , and  215   c  includes a second insertion hole  215   c  formed to be recessed from the bracket main body  210  in the radial direction. The second insertion hole  215   c  may be configured to communicate with the spring insertion portion  213 . 
     The third direction in which the second insertion hole  215   c  is recessed from the outer surface of the bracket main body  210  may intersect with the first direction in which the spring insertion portion  213  is recessed from the outer surface of the bracket main body  210 . 
     In addition, the third direction in which the second insertion hole  215   c  is recessed from the outer surface of the bracket main body  210  may intersect with the second direction in which the first insertion holes  215   a  and  215   b  are recessed from the outer surface of the bracket main body  210 . For example, the third direction may be perpendicular to the first and second directions. 
     The insertion members  251 ,  253 , and  255  include second insertion members  255  inserted into the second insertion holes  215   c . The second insertion member  255  may be formed as a columnar piece, for example. 
     The second insertion member  255  extends in the normal direction of the spring part inserted into the spring insertion part  213  and can be in contact with the surface of the spring part. For example, the second insertion member  255  can press the spring part. 
     According to this configuration, one point of the outer surface of the spring part inserted into the spring insertion portion  213  can be in contact with and be pressed by the first insertion members  251  and  253  and the other point thereof can be in contact with and be pressed by the second insertion member  255 . Therefore, in the driving process of the linear compressor  10 , even if a load acts on the spring assembly  100  in an axial direction or a radial direction, the first to third spring parts  110 ,  120 , and  130  can be maintained in a state of being stably fixed in the fixing bracket  200 . 
     The body coupling portion  220  is provided on both sides of the bracket main body  210  and may have a fastening hole  223  into which the first coupling member  65  or the second coupling member  75  can be inserted. 
     The body coupling portion  220  provided on the first fixing bracket  200   a  is coupled to the supporter body  61  of the supporter  60  and the body coupling portion  220  provided on the second fixing bracket  200   b  can be coupled to the cover body  71  of the rear cover  70 . 
       FIG.  7    is a sectional view taken along line  7 - 7 ′ of  FIG.  3   . 
     Referring to  FIG.  7   , the spring assembly  100  according to the first embodiment of the present invention is provided between the supporter  60  and the rear cover  70  and can elastically support the reciprocating movable portion P (see  FIG.  1   ). 
     The spring assembly  100  includes the first to third spring parts  110 ,  120 , and  130  which are coupled to a plurality of points of the supporter  60  and the rear cover  70  to form a single coil spring. For example, the plurality of points form three points, and the spring assembly  100  can support the supporter  60  and the rear cover  70  by three points by means of the first to third spring parts  110 ,  120 , and  130 . The three points may form a central angle of 120 degrees at equidistant intervals based on the center of the supporter  60  and the rear cover  70 . 
     The first side portion  110   a  which are provided to each of the first to third spring parts  110 ,  120 , and  130  may be inserted into the first fixing bracket  200   a  and the first fixing bracket  200   a  may be coupled to the supporter  60 . The first and second insertion members  251 ,  253 , and  255  provided on the first fixing bracket  200   a  may support the first to third spring parts  110 ,  120 , and  130  by being in contact with the first side portion  110   a.    
     The second side portion  110   b  of each of the first to third spring parts  110 ,  120 , and  130  may be inserted into the second fixing bracket  200   b  and the second fixing bracket  200   b  may be coupled to the rear cover  70 . The first and second insertion members  251 ,  253 , and  255  provided on the second fixing bracket  200   b  can support the first to third spring parts  110 ,  120 , and  130  by being in contact with the second side portion  110   b.    
     In a process of operating the linear compressor  10 , a load F 1  in the axial direction acts on the spring assembly  100  to cause tensile or compressive deformation in the axial direction. At this time, since the first and second fixing brackets  200   a  and  200   b  are in a state of being axially fixed to the supporter  60  and the rear cover  70  by the first and second coupling members  65  and  75 , respectively, the load F 1  may be canceled by the fixing force F 1 ′ of the first and second coupling members  65  and  75 . 
     In addition, since the first insertion members  251  and  253  inserted in the first and second fixing brackets  200   a  and  200   b  in the axial direction are in contact with the first and second side portions  110   a  and  110   b  to form a supporting force F 1 ′, it is possible to prevent axial deformation or breakage of the first and second side portions  110   a  and  110   b  due to the load F 1 . 
     Meanwhile, in a process of operating the linear compressor  10 , the spring assembly  100  may be deformed laterally by a load in the radial direction, that is, a lateral force F 2  acting. At this time, since the second insertion member  255  inserted into the first and second fixing brackets  200   a  and  200   b  in the radial direction is in contact with the first and second side portions  110   a  and  110   b  to form a supporting force F 2 ′, the radial deformation or breakage of the first and second side portions  110   a  and  110   b  by the load F 2  can be prevented. 
     Hereinafter, a second embodiment of the present invention will be described. Since the present embodiment differs from the first embodiment in the configuration of the fixing bracket, differences will be mainly described, and the description and the reference numerals of the first embodiment are used for the same portions as those in the first embodiment. 
       FIG.  8    is a perspective view illustrating a state where a spring assembly according to a second embodiment of the present invention is coupled to a supporter and a rear cover,  FIG.  9    is a perspective view illustrating a configuration of a spring part and a fixing bracket constituting a spring assembly according to a second embodiment of the present invention, and  FIG.  10    is a front view illustrating a configuration of a spring part and a fixing bracket constituting a spring assembly according to a second embodiment of the present invention. 
     Referring to  FIGS.  8  to  10   , the spring assembly  100   a  according to the second embodiment of the present invention includes the first to third spring parts  110 ,  120 , and  130 . The description of the first to third spring parts  110 ,  120 , and  130  uses the description of the first embodiment. 
     The spring assembly  100   a  is connected to the supporter  60  and the rear cover  70  so as to elastically support the supporter  60  and the rear cover  70 . 
     The description of the configuration of the supporter  60 , that is, a supporter body  61 , a supporter opening  62 , a supporter groove  63 , a piston fastening hole  66 , and a supporter recessed portion  67  uses the description of the first embodiment. In addition, the first coupling member  65  can be fastened to the fixing bracket  300  through the supporter  60 . 
     The description of the configuration of the rear cover  70 , that is, a cover body  71 , a cover opening  72 , a spring hole  73 , a leg hole  74 , and a cover recessed portion  76  uses the description of the first embodiment. In addition, the second coupling member  75  may pass through the rear cover  70  and be fastened to the fixing bracket  300 . 
     The spring assembly  100   a  includes fixing brackets  300  provided on both side portions of the three spring parts  110 ,  120 , and  130 . 
     The fixing bracket  300  includes a first fixing bracket  300   a  provided on the first side portion  100   a  of the three spring parts  110 ,  120 , and  130  and coupled to the supporter  60  and a second fixing bracket  300   b  provided on the second side portion  100   b  of the three spring parts  110 ,  120 , and  130  and coupled to the rear cover  70 . The first and second fixing brackets  300   a  and  300   b  may have the same configuration. 
     In detail, the fixing bracket  300  includes a bracket main body  310  into which the spring parts  110 ,  120 , and  130  are inserted, and body coupling portions  320  which are provided on both sides of the bracket main body  210  and are coupled to the supporter body  61  and the cover body  71 . The body coupling portion  320  may be formed with a fastening hole  323  into which the first coupling member  65  or the second coupling member  75  described in the first embodiment is inserted. 
     The bracket main body  310  includes a support part  311  inserted into a supporter recessed portion  67  of the supporter  60  or a cover recessed portion  76  of the rear cover  70 . The support part  311  may be located between the two body coupling portions  320 . 
     The bracket main body  310  is formed with a spring insertion portion  313  into which one side portion of the spring parts  110 ,  120 , and  130  is inserted. The spring insertion portion  313  includes a groove or a hole formed to be recessed from one surface of the bracket main body  310  in a radial direction. 
     The bracket main body  310  includes ribs  312   a  and  312   b  to which the bracket coupling member  330  is coupled. A plurality of ribs  312   a  and  312   b  are provided and the plurality of ribs  312   a  and  312   b  include a first rib  312   a  and a second rib  312   b  spaced from each other. The bracket coupling member  330  includes a screw or a rivet and may be fastened through the first and second ribs  312   a  and  312   b  arranged in the radial direction. In other words, the fastening direction of the bracket coupling member  330  may be a radial direction. 
     A portion of the spaced space between the first and second ribs  312   a  and  312   b  forms the spring insertion portion  313 . After the spring parts  110 ,  120 , and  130  are inserted into the spring insertion portion  313 , the bracket coupling member  330  is fastened to the first and second ribs  312   a  and  312   b  and thus the bonding force to the spring parts  110 ,  120 , and  130  can be increased. In other words, the bracket fastening member  330  can perform a fastener function with respect to the spring parts  110 ,  120 , and  130 . 
     The spring insertion portion  313  may be located between the support part  311  and the first and second ribs  312   a  and  312   b . In other words, the bracket main body  310  is configured such that the support part  311 , the spring insertion portion  313 , and the first and second ribs  312   a  and  312   b  are disposed in order (axially aligned), and thus the bracket main body  310  can stably fix the spring parts  110 ,  120 , and  130  to the supporter  60  and the rear cover  70 . 
       FIG.  11    is a sectional view taken along line  11 - 11 ′ of  FIG.  8   . 
     Referring to  FIG.  11   , the spring assembly  100   a  according to the second embodiment of the present invention is provided between the supporter  60  and the rear cover  70  and can elastically support the reciprocating movable portion P (see  FIG.  1   ). 
     The spring assembly  100   a  includes first to third spring parts  110 ,  120 , and  130  which are coupled to a plurality of points of the supporter  60  and the rear cover  70  and constitute one coil spring. For example, the plurality of points form three points, and the spring assembly  100  can support the supporter  60  and the rear cover  70  by three points by means of the first to third spring parts  110 ,  120 , and  130 . The three points may form a central angle of 120 degrees at equidistant intervals based on the center of the supporter  60  and the rear cover  70 . 
     The first side portion  110   a  provided to each of the first to third spring parts  110 ,  120  and  130  can be inserted into the spring insertion portion  313  of the first fixing bracket  300   a  and the first fixing bracket  300   a  can be coupled to the supporter  60 . In addition, the bracket fastening member  330  can be fastened to the two ribs  312   a  and  312   b  extending from the spring insertion portion  313  and thus the first fixing bracket  300   a  can be in close contact with the first side portion  110   a.    
     The second side portion  110   b  of each of the first to third spring parts  110 ,  120 , and  130  can be inserted into the second fixing bracket  300   b  and the second fixing bracket  300   b  can be coupled to the rear cover  70 . The bracket fastening member  330  can be fastened to the two ribs  312   a  and  312   b  extending from the spring insertion portion  313  so that the first fixing bracket  300   a  can be in close contact with the first side portion  110   a.    
     In a process of operating the linear compressor  10 , a load F 3  in the axial direction acts on the spring assembly  100 , so that tensile or compressive deformation in the axial direction may occur. At this time, since the first and second fixing brackets  300   a  and  300   b  are in a state of being axially fixed to the supporter  60  and the rear cover  70  by the first and second coupling members  65  and  75 , respectively, the load F 3  may be canceled by the fixing force F 3 ′ of the first and second coupling members  65  and  75 . 
     Meanwhile, in a process of operating the linear compressor  10 , the spring assembly  100  may be deformed laterally by a load, that is, a lateral force F 4  acting in the radial direction. At this time, since the bracket coupling member  330  radially inserted into the first and second fixing brackets  300   a  and  300   b  is in contact with the first and second side portions  110   a  and  110   b  to form a supporting force F 4 ′, it is possible to prevent the first and second side portions  110   a  and  110   b  from being radially deformed or damaged by the load F 4 .