Patent Publication Number: US-11035349-B2

Title: Linear compressor

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims the benefit of an earlier filing date and right of priority to Korean Patent Application No. 10-2018-0022977, filed on Feb. 26, 2018, in Korea, the entire contents of which is incorporated herein by reference. 
     TECHNICAL FIELD 
     The present disclosure generally relates to a linear compressor. 
     BACKGROUND 
     In general, a compressor is a mechanical apparatus that increases the pressure of air, a refrigerant, or other various working gases by compression using power from a power generator such as an electric motor or a turbine. Compressors are generally used for appliances or in other aspects of industry. 
     Compressors can be broadly classified as a reciprocating compressor, a rotary compressor, and a scroll compressor. 
     In a reciprocating compressor, a compression space is formed between a piston and a cylinder. A working gas is suctioned into or discharged from the compression space. The piston compresses a refrigerant by reciprocating straight, or linearly, in the cylinder. 
     In a rotary compressor, a compression space is formed between a roller and a cylinder. A working gas is suctioned into or discharged from the compression space. The roller compresses a refrigerant by eccentrically rotating on the inner side of the cylinder. 
     In a scroll compressor, a compression space is formed between an orbiting scroll and a fixed scroll. A working gas is suctioned into or discharged from the compression space. The orbiting scroll compresses a refrigerant by rotating on the fixed scroll. 
     SUMMARY 
     In one aspect, a linear compressor includes: a piston configured to reciprocate along an axial direction of the linear compressor; a resonance spring configured to elastically support the piston along the axial direction; a motor assembly configured to provide a driving force to the piston, the motor assembly comprising a magnet that is disposed radially outside the piston; and a supporter configured to be coupled to the piston, the magnet, and the resonance spring. The supporter comprises: a piston coupler coupled with the piston; a magnet coupler coupled with the magnet; and a spring coupler coupled with the resonance spring. The piston coupler, the magnet coupler, and the spring coupler are integrally formed by aluminum die casting. 
     In some implementations, the piston coupler has a circular flat plate shape that extends in a radial direction, and the magnet coupler extends axially in a forward direction on an outer side of the piston coupler. 
     In some implementations, the piston coupler comprises: a muffler hole configured to receive a suction muffler; and piston holes that are arranged radially outside the muffler hole and that are configured to receive piston fasteners for coupling the piston. 
     In some implementations, the piston comprises: a piston body having a cylindrical shape and extending along the axial direction; and a piston flange extending along the radial direction from the piston body. The piston coupler is configured to contact the piston flange and to couple with the piston flange by the piston fasteners. 
     In some implementations, the linear compressor further includes: a magnet frame having a cylindrical shape that extends in the axial direction and that has the magnet attached to the outer side thereof; and a magnet-fixing member that surrounds the outer side of the magnet frame, and that is configured to fix the magnet to the magnet frame. 
     In some implementations, the magnet frame is at least partially bonded to an inner side of the magnet coupler, and at least a portion of the magnet-fixing member surrounds the outer side of the magnet coupler. 
     In some implementations, the spring coupler is axially spaced from the piston coupler and the magnet coupler, and protrudes in the radial direction further than the piston coupler and the magnet coupler. 
     In some implementations, the supporter comprises: spring bridges configured to connect a plurality of spring couplers; and body bridges configured to connect the spring bridges, the piston coupler, and the magnet coupler. 
     In some implementations, the spring bridges have a ring shape connecting the spring couplers that are circumferentially spaced from each other. 
     In some implementations, the linear compressor further includes: assistant bridges that extend in the radial direction outward from the spring couplers, and that each connects a respective pair of the spring couplers. 
     In some implementations, an axial length of the assistant bridges is larger than an axial length of the spring couplers. 
     In some implementations, the body bridges extend in the axial direction from the spring couplers to the piston coupler and to the magnet coupler. 
     In some implementations, the supporter further comprises: assistant bridges configured to connect a plurality of spring couplers, wherein an axial length of the assistant bridges is larger than an axial length of the spring couplers. 
     In some implementations, the axial length of the assistant bridges is twice the axial length of the spring couplers. 
     In some implementations, the spring couplers are composed of a plurality of pairs of spring couplers that are circumferentially spaced from each other, and the assistant bridges each connects a respective pair of the spring couplers. 
     The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features will be apparent from the description and drawings, and from the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram illustrating an example of a view showing a linear compressor according to an implementation of the present disclosure; 
         FIG. 2  is a diagram illustrating an example of a view showing the linear compressor according to an implementation with a shell and shell covers separated; 
         FIG. 3  is a diagram illustrating an example of an exploded view showing the components in the linear compressor according to an implementation of the present disclosure; 
         FIG. 4  is a diagram illustrating an example of a cross-sectional view taken along line IV-IV′ of  FIG. 1 ; 
         FIG. 5  is a diagram illustrating an example of a view showing a magnet unit of the linear compressor according to an implementation of the present disclosure; 
         FIG. 6  is a diagram illustrating an example of a cross-sectional view taken along line VI-VI′ of  FIG. 5 ; and 
         FIGS. 7 to 9  are diagrams illustrating examples of views showing an all-in-one supporter of the linear compressor according to an implementation of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     In some scenarios, linear compressors implement a piston that is directly connected to a driving motor that generates a straight reciprocating motion. Such linear compressors can improve compression efficiency with a simple structure, while reducing mechanical loss due to conversion of motions. 
     A linear compressor typically suctions, compresses, and then discharges a refrigerant by reciprocating the piston along a straight direction in a cylinder, for example using a linear motor in a sealed shell. 
     In the linear motor, a magnet may be disposed between an inner stator and an outer stator, and the magnet may be reciprocated linearly by a mutual electromagnetic force between the magnet and the inner (or outer) stator. Further, the magnet may be operated while being connected to the piston, so that the piston suctions, compresses, and then discharges a refrigerant by reciprocating linearly in the cylinder. 
     In some structures, the permanent magnet and the piston compress a refrigerant by motion, and may implement a supporter and a magnet frame that connect the permanent magnet and the piston to each other. 
     The supporter and the magnet frame may be manufactured in metal plate shapes and combined with each other by a coupler. In such structures, the coupler and a coupling processor may increase manufacturing cost and manufacturing time. 
     Further, in such structures, the weight of an operation mechanism may be increased by the supporter and the magnet frame, so that operating the operation mechanism at a higher operation frequency may be difficult. 
     Implementations of the present disclosure may alleviate such problems by providing a linear compressor that can be operated at a relatively high operation frequency by reducing the weight of an operation mechanism. 
     In some implementations of the present disclosure, a linear compressor includes an all-in-one supporter that can be freely changed in shape by being manufactured through aluminum die casting without a change in strength and is reduced in weight. 
     In some implementations of the present disclosure, a linear compressor has a relatively simple coupling structure because the all-in-one supporter is combined with a magnet, a piston, and a resonance spring. 
     Reference will now be made in detail to the implementations of the present disclosure, examples of which are illustrated in the accompanying drawings. 
       FIG. 1  is a diagram illustrating an example of a view showing a linear compressor according to an implementation of the present disclosure.  FIG. 2  is a diagram illustrating an example of a view showing a linear compressor according to an implementation with a shell and shell covers separated. 
     As shown in the examples of  FIGS. 1 and 2 , a compressor  10 , which may be a linear compressor, according to an implementation of the present disclosure includes a shell  101  and shell covers  102  and  103  combined with the shell  101 . In a broad sense, the shell covers  102  and  103  may be understood as components of the shell  101 . 
     Legs  50  may be coupled to the bottom of the shell  101 . The legs  50  may be coupled to the base of a product on which the linear compressor  10  is installed. For example, the product may include a refrigerator and the base may include the base of the mechanical chamber of the refrigerator. Alternatively, the product may include the outdoor unit of an air-conditioning system and the base may include the base of the outdoor unit. 
     The shell  101  may have a substantially cylindrical shape and may be laid down horizontally or axially. On the basis of  FIG. 1 , the shell  101  may be horizontally elongated and may have a relatively small radial height. As an example, the linear compressor  10  may be small in height, so, for example, when the linear compressor  10  is disposed on the base of the mechanical chamber of a refrigerator, the height of the mechanical chamber can be reduced. 
     A terminal  108  may be disposed on the outer side of the shell  101 . The terminal  108  is understood as a component that transmits external power to a motor assembly  140  (see  FIG. 3 ) of the linear compressor. In particular, the terminal can be connected to a lead wire of a coil  141   c  (see  FIG. 3 ). 
     A bracket  109  is disposed outside the terminal  108 . The bracket  109  may include a plurality of brackets disposed around the terminal  108 . The bracket  109  may perform a function of protecting the terminal  108  from external shock. 
     Both sides of the shell  101  are open. The shell covers  102  and  103  can be coupled to both open sides of the shell  101 . In detail, the shell covers  102  and  103  include a first shell cover  102  coupled to one open side of the shell  101  and a second shell cover  103  coupled to the other open side of the shell  101 . The internal space of the shell  101  can be sealed by the shell covers  102  and  103 . 
     In the example of  FIG. 1 , the first shell cover  102  may be positioned at the right side of the linear compressor  10  and the second shell cover  103  may be positioned at the left side of the linear compressor  10 . In other words, the first and second shell covers  102  and  103  may be arranged opposite each other. 
     The linear compressor  10  further includes a plurality of pipes  104 ,  105 , and  106  disposed at the shell  101  or the shell covers  102  and  103  to suction, discharge, or inject a refrigerant. 
     The pipes  104 ,  105 , and  106  include a suction pipe  104  for suctioning a refrigerant into the linear compressor  10 , a discharge pipe  105  for discharging a compressed refrigerant out of the linear compressor  10 , and a process pipe  106  for supplementing the linear compressor  10  with a refrigerant. 
     For example, the suction pipe  104  may be coupled to the first shell cover  102 . A refrigerant can be suctioned into the linear compressor  10  axially through the suction pipe  104 . 
     The discharge pipe  105  may be coupled to the outer side of the shell  101 . The refrigerant suctioned through the suction pipe  104  can be compressed while axially flowing. The compressed refrigerant can be discharged through the discharge pipe  105 . The discharge pipe  105  may be positioned closer to the second shell cover  103  than the first shell cover  102 . 
     The process pipe  106  may be coupled to the outer side of the shell  101 . A worker can inject a refrigerant into the linear compressor  10  through the process pipe  106 . 
     The processor pipe  106  may be coupled to the shell  101  at a different height from the discharge pipe  105  to avoid interference with the discharge pipe  105 . The height is understood as the vertical (or radial) distance from the legs  50 . Since the discharge pipe  105  and the process pipe  105  are coupled at different heights to the outer side of the shell  101 , work can be conveniently performed. 
     At least a portion of the second shell cover  103  may be positioned on the inner side of the shell  101 , close to the position where the process pipe  106  is coupled. In other words, at least a portion of the second shell cover  103  can act as resistance against the refrigerant injected through the process pipe  106 . 
     Accordingly, in terms of a channel for a refrigerant, the size of the channel for the refrigerant that flows inside through the processor pipe  106  is decreased by the second shell cover  103  when entering the shell  101  and then increased through the shell  101 . While a refrigerant flows through the channel, it may evaporate due to a drop of pressure, and in this process, oil contained in the refrigerant can be separated. Accordingly, the refrigerant without oil separated flows into a piston  130  (see  FIG. 3 ), so the performance of compressing a refrigerant can be improved. The oil may be understood as a working oil existing in a cooling system. 
     A cover supporting portion  102   a  is formed on the inner side of the first shell cover  102 . A second retainer  185  to be described below may be coupled to the cover supporting portion  102   a . The cover supporting portion  102   a  and the second retainer  185  may be understood as a mechanism that supports the body of the linear compressor  10 . The body of the compressor may include a part disposed in the shell  101 , and for example, it may include an operation mechanism that reciprocates forward and backward and a supporting mechanism that supports the operation mechanism. 
     The operation mechanism may include a piston  130 , a magnet  146 , a supporter  137 , and a muffler  150 , which will be described below. The supporting mechanism may include resonance springs  176   a  and  176   b , a rear cover  170 , a stator cover  149 , a first retainer  165 , and a second retainer  185 , which will be described below. 
     Stoppers  102   b  may be formed on the inner side of the first shell cover  102 . The stoppers  102   b  are understood as parts that prevent the body of the compressor, particularly, the motor assembly  140  from being damage by hitting against the shell  101  due to vibration or shock that is generated while the linear compressor  10  is carried. The stoppers  102   b  are positioned close to the rear cover  170  to be described below, so when the linear compressor  10  is shaken, the rear cover  170  is held by the stoppers  102   b , thereby preventing shock from being transmitted to the motor assembly  140 . 
     Spring couplers  101   a  may be disposed on the inner side of the shell  101 . For example, the spring couplers  101   a  may be positioned close to the second shell cover  103 . The spring couplers  101   a  may be coupled to a second supporting spring  186  of the first retainer  165 . Since the spring couplers  101   a  and the first retainer  165  are coupled to each other, the body of the compressor can be stably supported in the shell  101 . 
       FIG. 3  is a diagram illustrating an example of an exploded view showing components in a linear compressor according to an implementation of the present disclosure. 
       FIG. 4  is a diagram illustrating an example of a cross-sectional view taken along line IV-IV′ of  FIG. 1 . 
     Referring to the examples of  FIGS. 3 and 4 , the linear compressor  10  according to an implementation of the present disclosure includes the cylinder  120  disposed in the shell  101 , the piston  130  reciprocating straight in the cylinder  120 , and the motor assembly  140  that is a linear motor providing a driving force to the piston  130 . When the motor assembly  140  is operated, the piston  130  can be axially reciprocated. 
     The linear compressor  10  further includes a suction muffler  150  combined with the piston  130  to reduce noise that is generated by the refrigerant suctioned through the suction pipe  104 . The refrigerant suctioned through the suction pipe  104  flows into the piston  130  through the suction muffler  150 . For example, the flow noise of the refrigerant can be reduced while the refrigerant flows through the suction muffler  150 . 
     The suction muffler  150  includes a plurality of mufflers  151 ,  152 , and  153 . The mufflers include a first muffler  151 , a second muffler  152 , and a third muffler  153  that are assembled together. 
     The first muffler  151  is disposed in the piston  130  and the second muffler  152  is coupled to the rear end of the first muffler  151 . The third muffler  153  receives the second muffler  152  and may extend rearward from the first muffler  151 . In respect of the flow direction of a refrigerant, the refrigerant suctioned through the suction pipe  104  can sequentially flow through the third muffler  153 , the second muffler  152 , and the first muffler  151 . The flow noise of the refrigerant can be reduced in this process. 
     The suction muffler  150  may further include a muffler filter  155 . The muffler filter  155  may be disposed at the interface between the first muffler  151  and the second muffler  152 . For example, the muffler filter  155  may have a circular shape and the outer side of the muffler filter  155  can be supported between the first and second mufflers  151  and  152 . 
     Directions are defined as follows. 
     The term “axial direction” may be understood as the reciprocation direction of the piston  130 , that is, the horizontal direction in  FIG. 4 . In the “axial direction”, the direction going toward the compression space P from the suction pipe  104 , that is, the flow direction of a refrigerant is defined as a “forward direction” and the opposite direction is defined as a “rear direction” When the piston  130  is moved forward, the compression space P can be compressed. 
     In some scenarios, the term “radial direction”, which is the direction perpendicular to the reciprocation direction of the piston  130 , may refer to the vertical direction in  FIG. 4 . 
     The piston  130  include a substantially cylindrical piston body  131  and a piston flange  132  radially extending from the piston body  131 . The piston body  131  can reciprocate in the cylinder  120  and the piston flange  132  can reciprocate outside the cylinder  120 . 
     The cylinder  120  includes a cylinder body  121  axially extending and a cylinder flange  122  formed on the outer side of the front portion of the cylinder body  121 . At least a portion of the first muffler  151  and at least a portion of the piston body  131  are received in the cylinder  120 . 
     A gas inlet  126  through which at least some of the refrigerant discharged through a discharge valve  161  flows inside is formed at the cylinder body  121 . The gas inlet  126  may be radially recessed from the outer side of the cylinder body  121 . 
     The gas inlet  126  may be circumferentially formed around the outer side of the cylinder body  121  about the central axis. A plurality of gas inlets  126  may be provided. For example, two gas inlets  126  may be provided. 
     The cylinder body  121  includes a cylinder nozzle  125  extending radially inward from the gas inlet  126 . The cylinder nozzle  125  may extend to the inner side of the cylinder body  121 . The refrigerant flowing inside through the gas inlet  126  and the cylinder nozzle  125  may be understood as a refrigerant that is used as a gas bearing between the piston  130  and the cylinder  120 . 
     The compression space P in which a refrigerant is compressed by the piston  130  is defined in the cylinder  120 . Suction holes  133  allowing for a refrigerant to flow into the compression space P are formed at the front side of the piston body  131  and a suction valve  135  for selectively opening the suction hole  133  is disposed ahead of the suction holes  133 . 
     Further, a fastening hole  136   a  to which a predetermined fastener  136  is fastened is formed at the front side of the piston body  131 . In detail, the fastening hole  136   a  is positioned at the center of the front side of the piston body  131  and the suction holes  133  are arranged around the fastening hole  136   a . The fastener  136  is inserted in the fastening hole  136   a  through the suction valve  135 , thereby fixing the suction valve  135  to the front side of the piston body  131 . 
     In some implementations, a discharge cover and a discharge valve assembly are disposed ahead of the compression space P. For example, the discharge cover  160  defines a discharge space  160   a  for the refrigerant that is discharged from the compression space P. The discharge valve assembly is coupled to the discharge cover  160  and is configured to selectively discharge the refrigerant compressed in the compression space P. The discharge space  160   a  includes a plurality of sections divided by the inner side of the discharge cover  160 . The sections are arranged in the front-rear direction and can communicate with each other. 
     The discharge valve assembly includes a discharge valve  161  that allows a refrigerant to flow into the discharge space  160   a  of the discharge cover  160  by opening when the pressure in the compression space P becomes a discharge pressure or more. The discharge valve assembly also includes a spring assembly  163  that is disposed between the discharge valve  161  and the discharge cover  160  and axially provides elasticity. 
     The spring assembly  163  includes a valve spring  163   a  and a spring supporting portion  163   b  for supporting the valve spring  163   a  to the discharge cover  160 . For example, the valve spring  163   a  may include a plate spring. The spring supporting portion  163   b  may be integrally formed with the valve spring  163   a  by injection molding. 
     The discharge valve  161  is coupled to the valve spring  163   a  and the rear portion or the rear side of the discharge valve  161  is disposed to be able to be supported by the front side of the cylinder  120 . When the discharge valve  161  is in contact with the front side of the cylinder  120 , the compression space P is maintained in a sealing state, and when the discharge valve  161  is spaced from the front side of the cylinder  120 , the compression space P is opened and the compressed refrigerant in the compression space P can be discharged. 
     Accordingly, in some implementations, the compression space P may be a space that is defined between the suction valve  135  and the discharge valve  161 . The suction valve  135  may be formed at a side of the compression space P, and the discharge valve  161  may be disposed at the other side of the compression space P (e.g., opposite the suction valve  135 ). 
     When the pressure in the compression space P decreases to a suction pressure or less, and is lower than a discharge pressure while the piston  130  reciprocates in the cylinder  120 , then the suction valve  135  is opened and a refrigerant is suctioned into the compression space P. However, when the pressure in the compression space P increases to the suction pressure or more, then the refrigerant in the compression space P is compressed with the suction valve  135  closed. 
     When the pressure in the compression space P increases to the discharge pressure or more, then the valve spring  163   a  opens the discharge valve  161  by deforming forward and a refrigerant is discharged from the compression space P into the discharge space  160   a . When the refrigerant finishes being discharged, then the valve spring  163   a  provides a restoring force to the discharge valve  161 , so that the discharge valve  161  is closed. 
     In some implementations, the linear compressor  10  further includes a cover pipe  162   a  coupled to the discharge cover  160  to discharge the refrigerant flowing through the discharge space  160   a  of the discharge cover  160 . For example, the cover pipe  162   a  may be made of metal. 
     The linear compressor  10  further includes a loop pipe  162   b  coupled to the cover pipe  162   a  to transmit the refrigerant flowing through the cover pipe  162   a  to the discharge pipe  105 . The loop pipe  612   b  may be coupled to the cover pipe  162   a  at a side and to the discharge pipe  105  at the other side. 
     In some implementations, the loop pipe  162   b  is made of a flexible material and may have a relatively large length. The loop pipe  162   b  may be rounded along the inner side of the shell  101  from the cover pipe  162   a  and coupled to the discharge pipe  105 . For example, the loop pipe  162   b  may be wound. 
     The linear compressor  10  further includes a frame  110 . The frame  110  is component for fixing the cylinder  120 . For example, the cylinder  120  may be forcibly fitted in the frame  110 . The cylinder  120  and the frame  110  may be made of aluminum or an aluminum alloy. 
     The frame  110  includes a substantially cylindrical frame body  111  and a frame flange  112  radially extending from the frame body  111 . The frame body  111  is disposed to surround the cylinder  120 . That is, the cylinder  120  may be received in the frame body  111 . The frame flange  112  may be coupled to the discharge cover  160 . 
     A gas hole  114  allowing at least some of the refrigerant discharged through the discharge valve  161  to flow to the gas inlet  126  is formed at the frame  110 . The gas hole  114  connects the frame flange  112  and the frame body  111  to each other. 
     The motor assembly  140  includes an outer stator  141 , an inner stator  148  spaced inward from the outer stator  141 , and a magnet  146  disposed in the space between the outer stator  141  and the inner stator  148 . 
     The magnet  146  can be reciprocated straight by a mutual electromagnetic force with the outer stator  141  and the inner stator  148 . The magnet  146  may be a single magnet having one pole or may be formed by combining a plurality of magnets having three poles. 
     The inner stator  148  is fixed to the outer side of the frame body  111 . The inner stator  148  is formed by stacking a plurality of laminations radially outside the frame body  111 . 
     The outer stator  141  includes a coil assembly and a stator core  141   a . The coil assembly includes a bobbin  141   b  and a coil  141   c  that is circumferentially wound around the bobbin  141   b.    
     The coil assembly further includes a terminal  141   d  leading or exposing a power line connected to the coil  141   c  to the outside of the outer stator  141 . The terminal  141   d  may extend through the frame flange  112 . 
     The stator core  141   a  includes a plurality of core blocks formed by circumferentially stacking a plurality of laminations. The core blocks may be arranged around at least a portion of the coil assembly. 
     A stator cover  149  is disposed at a side of the outer stator  141 . In the outer stator  141 , a side may be supported by the frame flange  112  and the other side may be supported by the stator cover  149 . Consequently, the frame flange  112 , the outer stator  141 , and the stator cover  149  are sequentially disposed in the axial direction. 
     The linear compressor  10  further includes cover fasteners  149   a  for fastening the stator cover  149  and the frame flange  112 . The cover fasteners  149   a  may extend forward toward the frame flange  112  through the stator cover  149  and may be coupled to the frame flange  112 . 
     The linear compressor  10  further includes a rear cover  170  coupled to the stator cover  149 , extending rearward, and supported by the second retainer  185 . 
     In detail, the rear cover  170  has three supporting legs and the three supporting legs may be coupled to the rear side of the stator cover  149 . A spacer  181  may be disposed between the three supporting legs and the rear side of the stator cover  149 . It is possible to determine the distance from the stator cover  149  to the rear end of the rear cover  170  by adjusting the thickness of the spacer  181 . 
     The linear compressor  10  further includes an intake guide  156  coupled to the rear cover  170  to guide a refrigerant into the suction muffler  150 . The intake guide  156  may be at least partially inserted in the suction muffler  150 . 
     The linear compressor  10  further includes a plurality of resonance springs  176   a  and  176   b  of which the natural frequencies are adjusted such that the piston  130  can be resonated. By the resonance springs  176   a  and  176   b , the operation mechanism that reciprocates in the linear compressor  10  can be stably operated and vibration or noise by movement of the operation mechanism can be reduced. 
     The linear compressor  10  further includes the first retainer  165  coupled to the discharge cover  160  and supporting a side of the body of the compressor  10 . The first retainer  165  is disposed close to the second shell cover  103  and can elastically support the body of the compressor  10 . In detail, the first retainer  165  includes a first supporting spring  166 . The first supporting spring  166  may be coupled to the spring couplers  101   a.    
     The linear compressor  10  further includes the second retainer  185  coupled to the rear cover  170  and supporting the other side of the body of the compressor  10 . The second retainer  185  is coupled to the first shell cover  102  and can elastically support the body of the compressor  10 . In detail, the second retainer  185  includes a second supporting spring  186 . The second supporting spring  186  may be coupled to the cover supporting portion  102   a.    
     In some implementations, the linear compressor  10  further includes a plurality of seals for more firmly combining the frame  110  and the components around the frame  110 . For example, the seals may have a ring shape. 
     As a detailed example, the seals may include a first seal  127  disposed at the joint between the frame  110  and the discharge cover  160 . The seals further includes second and third seals  128  and  129   a  disposed at the joint between the frame  110  and the cylinder  120  and a fourth seal  129   b  disposed at the joint between the frame  110  and the inner stator  148 . 
     The linear compressor  10  includes a magnet unit  200  in which the magnet  146  is disposed. The magnet unit  200  is disposed to support the piston  130 . An example of the magnet unit  200  is described in detail hereafter. 
       FIG. 5  is a diagram illustrating an example of an exploded view of a magnet unit of a linear compressor according to an implementation of the present disclosure and  FIG. 6  is a diagram of an example of a cross-sectional view taken along line VI-VI′ of  FIG. 4 . 
     As shown in the examples of  FIGS. 5 and 6 , the magnet unit  200  includes a plurality of magnets  146  and a magnet frame  201  holding the magnet  146 . The magnet frame  201  may be formed in a cylindrical shape and the magnets  146  may be attached to the outer side of the magnet frame  201 . 
     As a detailed example, the magnet frame  201  is formed in an axially hollow cylindrical shape and has a receiving space  201   a  therein for receiving the frame body  111  and the inner stator  148  coupled to the frame body  111 . For example, the magnet frame  201  has a radius larger than that of the inner stator  148 . 
     The magnets  146  may be disposed at the front portion in the axial direction of the magnet frame  201 . The magnets  146  may be circumferentially arranged on the outer side of the magnet frame  201 . 
     The magnet unit  200  further includes a magnet-fixing ring  202  for fixing the magnets  146 . The magnet fixing ring  202  may be formed in a ring shape fitted on the outer side of the magnet frame  201 . Referring to  FIG. 6 , the magnet-fixing ring  202  may be disposed at the front end of the magnet frame  201  in contact with a side of each of the magnets  146 . 
     The magnet unit  200  further includes a magnet-fixing member  205  surrounding the outer side of the magnet frame  201 . In particular, the magnet-fixing member  205  is combined with the magnet frame  201  to surround the magnets  146  and the magnet-fixing ring  202 . 
     For example, the magnet-fixing member  206  may be an adhesive having a predetermined adhesive force. Accordingly, by bonding the magnet-fixing member  206  to the magnet frame  201  to surround the magnets  146  and the magnet-fixing ring  202 , the magnets  146  and the magnet-fixing ring  202  can be fixed. 
     The magnet unit  200  further includes an all-in-one supporter  210  (e.g., as part or whole of supporter  137  in  FIG. 2 ). In some implementations, the all-in-one supporter  210  is manufactured by aluminum die casting. The all-in-one supporter  210  may be formed in various integrated shapes, hence being referred to as an “all-in-one” supporter. However, the term “all-in-one” when used in this context is not limited to a particular combination of components, and instead generally refers to an integrated nature of the supporter  137 . 
     In the example of  FIGS. 5 and 6 , the all-in-one supporter  210  has a piston coupler  2100 , a magnet coupler  2110 , and a spring coupler  2120 . In some implementations, the all-in-one supporter  210  may be a component that is combined (e.g., coupled) with the piston  130 , the magnets  146 , and the resonance springs  176   a  and  176   b.    
       FIGS. 7 to 9  are diagrams showing examples of an all-in-one supporter of a linear compressor according to an implementation of the present disclosure. 
     As shown in the examples of  FIGS. 7 to 9 , in some implementations, the all-in-one supporter  210  may be a single unit. However, for convenience of description herein, the piston coupler  2100 , magnet coupler  2110 , and spring coupler  2120  will be described separately. 
     The piston coupler  2100  is formed in a circular flat plate shape radially extending. The radius of the piston coupler  2100  may correspond to the maximum radius of the piston flange  132 . 
     The piston coupler  2100  has a muffler hole  2101  for fitting the suction muffler  150  and piston holes  2102  for coupling the piston flange  132 . The muffler hole  2101  may have a size corresponding to the outer side of the suction muffler  150 . 
     In detail, the muffler hole  2101  is formed at the center of the piston coupler  2100  and the piston holes  2102  are formed radially outside the muffler hole  2101 . For example, three piston holes  2102  may be provided and arranged with intervals of 120 degrees around the muffler hole  2101 . 
     The linear compressor  10  further includes piston fasteners  132   a  (see  FIG. 4 ) for fastening the piston flange  132  and the all-in-one supporter  210 . The cover fasteners  132   a  are inserted in the piston holes  2102  and, in some implementations, holes may be formed at the piston flange  132  to correspond to the piston holes  2102 . 
     Piston-cut portions  2104  are formed between the piston holes  2102  through the piston coupler  2100 . In detail, the piston-cut portions  2104  may include cut portions that are configured to reduce the weight of the piston coupler  2100 . 
     In the related art, the piston-cut portions  2104  had various shapes and holes for coupling and arranging other components. However, since the all-in-one supporter  210  is a single unit, such structure is not needed and the piston-cut portions  2104  can be formed in a relatively simple shape. In particular, the piston-cut portions  2104  may be formed larger to reduce the weight. 
     Since the all-in-one supporter  210  is formed by aluminum die casting, the piston coupler  2100  can be formed in various shapes. Accordingly, it is possible to effectively reduce the weight by cutting off unnecessary portions. 
     Referring to the example of  FIG. 8 , the portions where the piston-cut portions  2104  are formed around the edge may be formed relatively thick. This may provide additional strength to compensate for the cut-off portions. For example, in scenarios where the all-in-one supporter  210  is formed by aluminum die casting, the thickness maybe different. 
     The magnet coupler  2110  is formed in a ring shape axially extending forward from the outer side of the piston coupler  2100 . The inner side of the magnet coupler  2110  has a size corresponding to the outer side of the magnet frame  201 . Accordingly, as shown in the example of  FIG. 6 , the rear end of the magnet frame  201  can be received in the magnet coupler  2110 . 
     In some implementations, a magnet seat  2111  recessed radially inward is formed on the outer side of the magnet coupler  2110 . The magnet seat  2111  may be a part formed so that the magnet-fixing member  205  can be coupled in closer contact with the magnet coupler  2110 . 
     A combination of the all-in-one supporter  210  and the magnets  146  is described with reference to the example of  FIG. 6 . In this example, the rear end of the magnet frame  201  is received in the magnet coupler  2110 . The rear end of the magnet frame  201  can be axially seated on the piston coupler  2100 . 
     The magnets  146  and the magnet-fixing ring  202  are attached to the outer side of the magnet frame  201 . The magnet-fixing member  205  is coupled to the outer side of the magnet frame  201  and the outer side of the magnet coupler  2110 . 
     For example, the magnet frame  201  is disposed radially inside the magnet coupler  2110  and the magnet-fixing member  205  is disposed radially outside the magnet coupler  2110 . Accordingly, the magnets  146  and the magnet frame  201  can be fixed to the all-in-one supporter  210 . This assembly is the magnet unit  200  described above. 
     The spring coupler  2120  is formed in a circular flat plate shape radially extending. The spring coupler  2120  is disposed radially further outside than the magnet coupler  2110  and the piston coupler  2100 . The spring coupler  2120  may have a size corresponding to the resonance springs  176   a  and  176   b  to support the resonance springs  176   a  and  176   b.    
     The resonance springs include first resonance springs  176   a  disposed axially ahead of the spring coupler  2120  and second resonance springs  176   b  disposed axially behind the spring coupler  2120 . That is, the spring coupler  2120  is disposed axially between the first resonance springs  176   a  and the second resonance springs  176   b.    
     The first resonance springs  176   a  are disposed axially between the spring coupler  2120  and the stator cover  149  and the second resonance springs  176   b  are disposed axially disposed between the spring coupler  2120  and the rear cover  170 . Consequently, the stator cover  149 , first resonance springs  176   a , spring coupler  2120 , second resonance springs  176   b , and rear cover  170  are axially sequentially arranged. 
     The first and second resonance springs  176   a  and  176   b  may be each circumferentially spaced from each other. For example, the first and second resonance springs  176   a  and  176   b  may be respectively six pieces and pairs of each of the first and second resonance springs are circumferentially arranged with intervals of 120 degrees. Further, the spring couplers  2120  may be six pieces and pairs may be circumferentially arranged with intervals of 120 degrees. 
     The all-in-one supporter  210  has bridges  2130  and  2140  connecting the piston coupler  2100 , the magnet coupler  2110 , and the spring coupler  2120 . 
     The bridges  2130  and  2140  include spring bridges  2130  connecting the spring couplers  2120  and body bridges  2140  connecting the spring bridges  2130 , the piston coupler  2100 , and the magnet coupler  2110 . 
     The spring bridges  2130  are formed in a ring shape connecting the spring couplers  2120  circumferentially spaced from each other. The spring bridges  2130  have a size corresponding to the magnet coupler  2110  and may be arranged axially in parallel with each other. 
     The body bridges  2140  axially extend to connect the spring bridges  2130  and the magnet coupler  2110  that are axially spaced from each other. For example, the magnet coupler  2110 , the body bridges  2140 , and the spring bridges  2130  axially extend. Further, in some implementations, the magnet coupler  2110 , the body bridges  2140 , and the spring bridges  2130  may have an entirely cylindrical shape. 
     The piston coupler  2100  is disposed radially inward at the upper end of the body bridges  2140 . For example, the magnet coupler  2110  axially extends upward from the upper ends of the body bridges  2140 , the piston coupler  2100  extends radially inward from the upper ends of the body bridges  2140 , and the spring bridges  2130  extend axially downward from the lower ends of the body bridges  2140 . 
     Body-cut portions  2142  are formed at the body bridges  2140 . As a detailed example, the body-cut portions  2142  can function as passage for smooth flow of a refrigerant. Accordingly, the larger the body-cut portions  2142 , the smoother the refrigerant can flow. 
     In particular, since the all-in-one supporter  210  is manufactured by aluminum die casting, the body-cut portions  2142  can be formed in desired sizes. That is, the body-cut portions  2142  may be formed smaller in comparison to those in the related art. The reduction of strength by the body-cut portions  2142  can be compensated by the thickness of the portions close to the body-cut portions  2142 . 
     The body-cut portions  2142  may be formed in various shapes. For example, the body-cut portions  2142  may be formed in the same area as the body bridges  2140  and spaced circumferentially with intervals of 120 degrees. That is, the weight of the body bridges  2140  can be reduced a half by the body-cut portions  2142 . 
     Accordingly, the body bridges  2140  may be formed in column shapes spaced circumferentially with intervals of 120 degrees. In some implementations, the cross-sections of the body bridges  2140  may have arc shapes. 
     The bridges  2130  and  2140  includes assistant bridges  2150  extending radially outward from the spring bridges  2130  and coupled to the spring couplers  2120 . 
     As a detailed example, the spring couplers  2120  extend radially outward from the spring bridges  2130 . Further, as described above, the spring couplers  2120  are provided in pairs and the assistant bridges  2150  each connect a pair of spring bridges  2130 . 
     For example, the pairs of spring couplers  2120  disposed circumferentially close to each other are respectively connected by the assistant bridges  2150  and the spring couplers  2120  circumferentially spaced from each other are connected by the spring bridges  2130 . That is, the assistant bridges  2150  may be at least portions of the spring bridges  2130 . 
     The assistant bridges  2150  and the spring bridges  2130  may be formed axially longer than the spring couplers  2120 . For example, the assistant bridges  2150  and the spring bridges  2130  may be formed thicker than the spring couplers  2120 . 
     Referring to the example of  FIG. 9 , the axial length, that is, the thickness of the spring bridges  2130 , corresponds to ‘a’ and furthermore, the axial length, that is, the thickness of the assistant bridges  2150 , corresponds to ‘b’. In this example, b is larger than a (i.e., b&gt;a) and b may be two times a (b=2a). However, these are merely examples and b may be of various values larger than a. 
     Such implementations may address a stress level that concentrates on the assistant bridges  2150  by movement of the first and second resonance springs  176   a  and  176   b . As such, some implementations may help prevent damage by increasing the thickness of the portions on which stress concentrates. 
     In some implementations, the shape of the all-in-one supporter  210  may be achieved by having the all-in-one supporter  210  manufactured by aluminum die casting. Such implementations may reduce the weight and maintain the strength by freely changing the shape. 
     Further, in some implementations, the all-in-one supporter  210  is a part that reciprocates with the magnets  146  and the piston  130 . Accordingly, as the weight is reduced, the all-in-one supporter  210  can more efficiently reciprocate and the linear compressor  10  according to an aspect of the present disclosure can be operated at a higher operation frequency. 
     According to implementations of the present disclosure, it is possible to freely change the shape by manufacturing the all-in-one supporter combined with the magnets, piston, and resonance springs through aluminum die casting. 
     In particular, it is possible to reduce the weight while maintaining the strength of the all-in-one supporter, and as the weight is reduced, the all-in-one supporter can more efficiently reciprocate. 
     In addition, since the weight of the operation mechanism including the all-in-one supporter is reduced, the linear compressor can be operated at a higher operation frequency. 
     Further, since the all-in-one supporter is combined with various components and performs various functions, the coupling structure is reduced, so the manufacturing time and coupling members are reduced, and accordingly, the manufacturing cost is reduced. 
     Although implementations have been described with reference to a number of illustrative implementations thereof, it should be understood that numerous other modifications and implementations can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this disclosure. More particularly, various variations and modifications are possible in the component parts and/or arrangements of the subject combination arrangement within the scope of the disclosure, the drawings and the appended claims. In addition to variations and modifications in the component parts and/or arrangements, alternative uses will also be apparent to those skilled in the art.