Patent Publication Number: US-2022235752-A1

Title: Reciprocating compressor

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to Korean Patent Application No. 10-2021-0009616, filed on Jan. 22, 2021, in Korea, the entire contents of which are hereby incorporated by reference in their entirety. 
     TECHNICAL FIELD 
     The present disclosure relates to a reciprocating compressor. 
     BACKGROUND 
     A reciprocating compressor is an apparatus that can compress a fluid, for example, by suctioning, compressing, and discharging a refrigerant based on a piston reciprocating in a cylinder. The reciprocating compressor may be classified into a connection type reciprocating compressor and a vibration type reciprocating compressor depending on driving manners of a piston. For instance, the connection type reciprocating compressor may compress a refrigerant based on reciprocation of a piston connected with a rotating shaft of a driving device through a connecting rod. The vibration type reciprocating compressor may compress the refrigerant based on reciprocation of a piston disposed in a cylinder and connected with a mover of a reciprocating motor to vibrate. 
     In some cases, the connection type reciprocating compressor may include a housing shell having an enclosed space, a driving device provided in the housing shell to provide driving force, a compression device connected with a rotating shaft of the driving device to compress a refrigerant through a reciprocating motion of the piston in the cylinder using the driving force received from the driving device, and a suction and discharge device to suction the refrigerant and to discharge the refrigerant compressed through the reciprocating motion of the compression device. 
     The suction and discharge device may include a valve assembly to open or close the suction space and the discharge space for the refrigerant, and a suction muffler and a discharge muffler to reduce noise caused in the procedure of opening or closing the valve assembly. 
     In some cases, the reciprocating compressor may include discharge pressure pulsations generated in the procedure of discharging the compressed refrigerant, and the discharge pressure pulsations cause a refrigerant pipe, which is connected with the compressor, to vibrate thereby totally increasing the noise of home appliances including the compressor. 
     The reciprocating compressor may be applied to a smaller-size home appliance such as a water purifier. In some cases, the noise caused by the smaller-size home appliance may degrade the reliability for the product. 
     SUMMARY 
     The present disclosure describes a reciprocating compressor having an improved inner structure to reduce a pressure pulsation of a refrigerant which is discharged. 
     For example, the present disclosure describes a reciprocating compressor that can reduce a pressure pulsation by providing a discharge guide device having a discharge fluid passage for a refrigerant, where the discharge fluid passage is defined inside a discharge muffler. 
     The present disclosure further describes a reciprocating compressor that can reduce a pressure pulsation of a refrigerant by defining a plurality of discharge rooms inside a discharge muffler by a muffler body, a wall, and a discharge guide device of a discharge muffler. 
     The present disclosure further describes a reciprocating compressor including a discharge guide device fixed inside a discharge muffler and at least one wall to reinforce the stiffness of the discharge muffler. 
     The present disclosure further describes a reciprocating compressor including a discharge guide device, where a pipe part of the discharge guide device has a bending shape such that a refrigerant discharged from a suction and discharge tank passes through a discharge fluid passage of a discharge guide device in the procedure of being discharged to a discharge part formed at a lower end portion of the discharge muffler. 
     The present disclosure further describes a reciprocating compressor including a fixing bracket provided in a discharge guide device such that a pipe part is firmly fixed inside a discharge muffler. 
     According to one aspect of the subject matter described in this application, a reciprocating compressor includes a cylinder that defines a compressing space and a discharge muffler configured to receive refrigerant compressed in the cylinder and to discharge the refrigerant. The discharge muffler includes a discharge muffler body and a discharge guide supported by the discharge muffler body. The discharge muffler body defines a discharge space configured to receive the refrigerant from the cylinder and includes a wall protruding from an inner circumferential surface of the discharge muffler body. The discharge guide is coupled to the wall and includes a pipe that defines a pipe inflow hole configured to receive the refrigerant from the discharge space and a pipe outflow hole configured to discharge the refrigerant. The discharge guide further includes a fixing bracket that couples the pipe to the discharge muffler body. 
     Implementations according to this aspect can include one or more of the following features. For example, the pipe can include a first pipe part that extends in a first direction and a second pipe part that extends from the first pipe part in a second direction that is different from the first direction. In some implementations, the discharge muffler body can define a discharge guide hole configured to introduce the refrigerant from the cylinder into the discharge muffler, where the pipe inflow hole is defined at the first pipe part and faces the discharge guide hole. 
     In some implementations, the discharge muffler body can further define a discharge part configured to discharge the refrigerant from the discharge muffler, where the pipe outflow hole is defined at the second pipe part and faces the discharge part. In some examples, the first direction is a vertical direction, and the second direction is a horizontal direction, where the discharge guide hole is spaced apart from the discharge part and defined above the discharge part in the vertical direction. 
     In some implementations, the fixing bracket can include a bracket body that defines an insertion groove coupled to the wall and has at least one stepwise section supported by the discharge muffler body. For instance, the at least one stepwise section can include a first stepwise section recessed from an outer surface of the bracket body, where the first stepwise section defines a first step width that is less than an outer width of the bracket body, and a second stepwise section recessed relative to the first stepwise section, where the second stepwise section defines a second step width that is less than the first step width. 
     In some examples, the discharge muffler body can include an inner wall that is spaced apart from an outer surface of the discharge muffler body and that includes a first jaw that supports the first stepwise section. The discharge muffler body can further include a wall protrusion part that is stepped inward relative to the inner wall, where the wall protrusion part includes a second jaw that supports the second stepwise section. 
     In some implementations, the reciprocating compressor can further include a tank that is disposed at one side of the cylinder and defines a discharge chamber configured to receive the refrigerant from the cylinder and to supply the refrigerant to the discharge space, where the discharge chamber has a primary discharge room configured to carry the refrigerant received from the cylinder. In some examples, the wall can divide the discharge space into one or more discharge rooms that are configured to receive the refrigerant from the primary discharge room. 
     In some implementations, the wall can include a first wall and a second wall that are spaced apart from each other, where the first wall and the second wall divide the discharge space into a plurality of discharge rooms that are configured to carry the refrigerant received from the cylinder. For example, the plurality of discharge rooms can include a secondary discharge room defined between the first wall and the discharge muffler body. In some examples, the plurality of discharge rooms can further include a tertiary discharge room defined between the second wall and the discharge muffler body and a quaternary discharge room defined between the first wall and the second wall, where the quaternary discharge room is in fluid communication with the tertiary discharge room. In some examples, the first wall separates the secondary discharge room from the quaternary discharge room. 
     In some implementations, the discharge muffler body can include a first muffler body that defines a discharge guide hole configured to introduce the refrigerant from the cylinder into the discharge muffler and a second muffler body that is coupled to the first muffler body and defines a discharge part configured to discharge the refrigerant from the discharge muffler, where the second muffler body has a bottom surface that supports the discharge guide. 
     In some implementations, the reciprocating compressor can include a tank disposed between the cylinder and the discharge muffler, where the tank defines a discharge chamber configured to receive the refrigerant from the cylinder and to discharge the refrigerant to the discharge space. The reciprocating compressor can further include a suction muffler disposed at one side of the tank and configured to supply the refrigerant to the tank. In some examples, the tank can be disposed between the suction muffler and the discharge muffler, where the tank faces the cylinder and connects the suction muffler to the discharge muffler. 
     In some examples, the tank can further define a suction chamber configured to receive the refrigerant from the suction muffler and to supply the refrigerant to the cylinder. 
     In some implementations, the reciprocating compressor can further include a shell that defines an enclosed space that accommodates the cylinder, the discharge muffler, the suction muffler, the tank, and the refrigerant, where the suction muffler defines a suction hole configured to introduce the refrigerant in the enclosed space into the suction muffler. In some examples, the suction muffler can further define a suction guide hole configured to supply the refrigerant in the suction muffler to the cylinder. 
     In some implementations, the inner structure of the discharge muffler can be improved to reduce the pressure pulsation of the refrigerant which is discharged. 
     In some implementations, the pressure pulsation can be reduced by providing the discharge guide device having the discharge fluid passage for a refrigerant, which is formed inside the discharge muffler. 
     In some implementations, the pressure pulsation of the refrigerant can be reduced by defining the plurality of discharge rooms inside the discharge muffler by the muffler body, the wall, and the discharge guide device of the discharge muffler. 
     In some implementations, at least one wall is included inside the discharge muffler, such that the discharge guide device can be firmly fixed inside the discharge muffler and the stiffness of the discharge muffler can be reinforced. 
     In some implementations, the pipe part of the discharge guide device is configured to have the bending shape, such that the refrigerant discharged from the suction and discharge tank easily passes through the discharge fluid passage of the discharge guide device in the procedure of being discharged to the discharge part formed at the lower end portion of the discharge muffler. 
     In some implementations, the fixing bracket can be provided in the discharge guide device such that the pipe part is firmly fixed inside the discharge muffler. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present disclosure will become more fully understood from the detailed description given herein below and the accompanying drawings, which are given by illustration only, and thus are not limitative of the present disclosure. 
         FIG. 1  is a perspective view showing an example of a reciprocating compressor. 
         FIG. 2  is a cross sectional view taken along line  2 - 2 ′ of  FIG. 1 . 
         FIG. 3  is a perspective view illustrating an example of a muffler assembly. 
         FIG. 4  is a front exploded perspective view illustrating the muffler assembly. 
         FIG. 5  is a perspective view illustrating the muffler assembly. 
         FIG. 6  is a view illustrating an example of a suction and discharge tank and first and third mufflers that are integrated with each other. 
         FIG. 7  is a perspective view illustrating an example of a second discharge muffler part coupled to a discharge guide device. 
         FIG. 8  is an exploded perspective view illustrating the second discharge muffler part and the discharge guide device. 
         FIG. 9  is a perspective view illustrating the discharge guide device. 
         FIG. 10  is a perspective view illustrating the discharge guide device. 
         FIG. 11  is a cross sectional view taken along line  11 - 11 ′ of  FIG. 3 . 
         FIG. 12  is a view illustrating an example of a refrigerant flow in a discharge muffler. 
         FIG. 13  is a graph illustrating an example of an experimental result showing an effect of reducing a pulsation with the discharge muffler having the discharge guide device. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to accompanying drawings, such that those skilled in the art can more apparently understand the present disclosure. It should be understood that the exemplary embodiments herein are provided only for the illustrative purpose, and various modifications of the embodiments are reproduced. In addition, the shapes and the sizes of elements in accompanying drawings will be exaggerated for more apparent description. 
       FIG. 1  is a perspective view illustrating an example of a reciprocating compressor, and  FIG. 2  is a cross sectional view taken along line  2 - 2 ′ of  FIG. 1 . 
     Referring to  FIGS. 1 and 2 , a reciprocating compressor  1  can include a shell  10  forming an outer appearance of the reciprocating compressor  1 . An enclosed space can be formed inside the shell  10 , and various components constituting the reciprocating compressor  1  can be received in the enclosed space. The shell  10  can be formed a metallic material. 
     A cavity can be formed in an inner space of the shell  10  to define the resonance frequency of the refrigerant. In some implementations, a structure of reducing noise caused in a cavity resonance frequency band of the refrigerant can be provided. 
     The shell  10  includes a lower shell  11  and an upper shell  16  provided at an upper side of the lower shell  11 . In detail, the lower shell  11  has a substantially hemispherical shape and forms a receiving space to receive various components, for example, a driving device  20 , a compressing device  30 , and a suction and discharge device  100 , together with the upper shell  16 . The lower shell  11  can be referred to as a “compressor body” and the upper shell  16  can be referred to as a “compressor cover.” 
     The lower shell  11  includes a suction pipe  12 , a discharge pipe  13 , a process pipe  14 , and a power supply. The suction pipe  12  is used to introduce a refrigerant into the shell  10 , and is mounted through the lower shell  11 . The suction pipe  12  can be mounted separately from the lower shell  11  or can be integrally formed with the lower shell  11 . 
     The discharge pipe  13  is used to discharge the refrigerant, which is compressed in the shell  10 , and is mounted through the lower shell  11 . The discharge pipe  13  can be separately mounted separately from the lower shell  11  or can be integrally formed with the lower shell  11 . 
     A discharge hose  60  (see  FIG. 3 ) is connected with the discharge pipe  13 . The refrigerant, which is introduced into the suction pipe  12  and compressed by the compressing device  30 , can be discharged to the discharge pipe  13  through the suction and discharge device  100  and the discharge hose  60 . 
     The process pipe  14 , which is a device provided to fill the refrigerant into the shell  10  after the inner portion of the shell  10  is sealed, can be mounted through the lower shell  11 . 
     The driving device  20  is provided in the inner space of the shell  10  to provide driving force. The driving device  20  can include a stator  21 , a rotor  24 , and a rotating shaft  22 . The stator  21  includes a stator core and a coil coupled to the stator core. 
     When power is applied to the coil, the coil generates electromagnetic force to perform electromagnetic interaction with the stator core and the rotor. Accordingly, the driving device  20  can generate driving force for a reciprocating motion of the compressing device  30 . 
     The rotor  24  has a magnet, and is rotatably provided inside the coil. The rotational force resulting from the rotation of the rotor  24  acts as driving force for driving the compressing device  20 . 
     The rotating shaft  22  can rotate together with the rotor  24 , and can be mounted through an inner portion of the rotor  24  in a vertical direction. In addition, the rotating shaft  22  is connected to a connecting rod  34  to transmit the rotational force generated by the rotor  24  to the compressing device  30   
     In detail, the rotating shaft  22  can include a base shaft  22   a , a rotational plate  22   b , and an eccentric shaft  22   c.    
     The base shaft  22   a  is mounted inside the rotor  24  in the vertical direction. When the rotor  24  rotates, the base shaft  22   a  can be rotated together with the rotor  24 . The rotational plate  22   b  can be installed on one side of the base shaft  22   a , and can be rotatably mounted to a cylinder block  31  to be described later. 
     The eccentric shaft  22   c  protrudes upward from a position eccentric from the axial center of the base shaft  22   a  to eccentrically rotate when the rotational plate  22   b  rotates. A connecting rod  34  is mounted on the eccentric shaft  22   c . As the eccentric shaft  22   c  eccentrically rotates, the connecting rod  34  can linearly reciprocate (a linear reciprocation motion) in a front-rear direction. 
     The compressing device  30  receives the driving force from the driving device  20  to compress the refrigerant through linear reciprocation motion. The compressing device  30  can include a cylinder block  31 , a connecting rod  34 , a piston  35 , and a piston pin  37 . 
     The cylinder block  31  is provided above the rotor  24 . In addition, the cylinder block  31  has a shaft opening such that the rotating shaft  22  passes through the shaft opening. A lower portion of the cylinder block  31  can rotatably support the rotational plate  22   b.    
     The cylinder  33  is provided at a front portion of the cylinder block  31  and arranged to receive the piston  35 . The piston  35  reciprocates in the front-rear direction, and a compressing space “C” for compressing the refrigerant is formed inside the cylinder  33 . 
     The connecting rod  34  is a device for transmitting the driving force, which is provided from the driving device  20 , to the piston  35 , and converts the rotational motion of the rotating shaft  22  into the linear reciprocation motion. In detail, the connecting rod  34  linearly reciprocates in the front-rear direction when the rotating shaft  22  rotates. 
     The piston  35  is a device for compressing the refrigerant, and is provided in the cylinder  33 . The piston  35  is connected with the connecting rod  34  and linearly reciprocates in the cylinder  33 , as the connecting rod  34  moves. The refrigerant introduced from the suction pipe  12  can be compressed in the cylinder  33 , as the piston  35  linearly reciprocates. 
     The piston pin  37  couples the piston  35  and the connecting rod  34 . In detail, the piston pin  37  can connect the piston  35  with the connecting rod  34  by passing through the piston  35  and the connecting rod  34  in the vertical direction. 
     The suction and discharge device  100  is configured to suction the refrigerant to be supplied to the compressing device  30  and to discharge the compressed refrigerant from the compressing device  30 . The suction and discharge device  100  can include a muffler assembly  110  and a discharge hose  60 . 
     The muffler assembly  110  transfers the suctioned refrigerant, which is received from the suction pipe  12 , into the cylinder  33 , and transfers the refrigerant, which is compressed in the compressing space “C’ of the cylinder  33 , to the discharge pipe  13 . To this end, the muffler assembly  110  has a suction space “S” for receiving the suctioned refrigerant from the suction pipe  12  and a discharge space “D” for receiving the refrigerant compressed in the compressing space C of the cylinder  33 . 
     In detail, the suctioned refrigerant from the suction pipe  12  can be introduced into the suction space “S” of a suction and discharge tank (or a tank)  120  through suction mufflers  130  and  140 . The refrigerant compressed in the cylinder  33  passes through discharge mufflers  150  and  160  through the discharge space “D” of the suction and discharge tank  120 , and is discharged of the compressor  1  through the discharge hose  60  and the discharge pipe  13 . For example, the suction mufflers  130  and  140  and the discharge mufflers  150  and  160  can be cases, containers, or reservoirs that define inner spaces configured to accommodate and guide the refrigerant. 
     The discharge hose  60  is a device to transfer the compressed refrigerant, which is contained in the discharge space “D,” to the discharge pipe  13 , and is integrally formed with a second discharge muffler part  160  of the discharge mufflers  150  and  160 . In detail, one portion of the discharge hose  60  can be coupled to the second discharge muffler part  160  to communicate with the discharge space “D,” or can be formed integrally with the second discharge muffler part  160 . 
     An opposite portion of the discharge hose  60  is coupled to the discharge pipe  13  through a connector  65 . The discharge hose  60  and the connector  65  can be jointed to each other or can be formed integrally with each other. 
     The connector  65  has a plurality of grooves, and ring members  66   a  and  66   b  can be installed in the plurality of grooves, respectively. The ring members  66   a  and  66   b  can be formed of rubber or synthetic resin material. 
       FIG. 3  is a perspective view illustrating an example configuration of the muffler assembly,  FIG. 4  is a front exploded perspective view illustrating an example configuration of the muffler assembly, and  FIG. 5  is a perspective view illustrating an example configuration of the muffler assembly. 
     Referring to  FIGS. 3 to 5 , the muffler assembly  110  can include a first suction muffler part  130  and a second suction muffler part  140  constituting the suction muffler. 
     The first suction muffler part  130  and the second suction muffler part  140  can be assembled, and a refrigerant suction space (or a suction fluid passage) can be defined inside the first and second suction mufflers  130  and  140  through the assembling between the first suction muffler part  130  and the second suction muffler part  140 . 
     When viewed based on  FIG. 3 , the first suction muffler part  130  can be coupled to an upper side of the second suction muffler part  140 . For example, the first suction muffler part  130  can include a hook  135 , and the second suction muffler part  140  can include a hook protrusion  145  coupled to the hook  135 . 
     Unlike the drawings, the hook protrusion can be provided on the first suction muffler part  130 , and the hook coupled to the hook protrusion can be provided on the second suction muffler part  140 . 
     The first suction muffler part  130  can include a first muffler body  131  including a suction guide hole  136 . An end portion of the first muffler body  131  can be open. 
     A first muffler flange  132  coupled to the second suction muffler part  140  can be provided on the first muffler body  131 . The first muffler flange  132  can be formed to be stepped from the first muffler body  131  such that an outer diameter of the first muffler flange  132  is greater than an outer diameter of the first muffler body  131 . 
     The first muffler flange  132  can be coupled to an open end portion of the second discharge muffler part  160 . For example, the first muffler flange  132  can be coupled to an outer portion of the second discharge muffler part  160 . 
     The second suction muffler part  140  can include a second muffler body  141  having a suction hole  142  communicating with the suction pipe  12 . 
     The combination of the first muffler body  131  of the first suction muffler part  130  and the second muffler body  141  of the second suction muffler part  140  can be collectively referred to as a “suction muffler body.” 
     The suction hole  142  can be formed through a portion of an outer circumferential surface of the second muffler body  141 . In addition, the suction hole  142  is positioned adjacent to the inside of one point of the lower shell  11  to which the suction pipe  12  is coupled. 
     The second suction muffler part  140  can include an oil drain part  148  such that oil separated from the refrigerant in the inner space of the suction mufflers  130  and  140  is discharged into the inner space of the shell  10 . The oil drain part  148  can protrude downward from a bottom surface of the second muffler body  141 . 
     The second suction muffler part  140  can further include a skirt  149  protruding downward from the bottom surface of the second muffler body  141  to prevent the oil discharged from the oil drain part  148  from scattering. The skirt  149  can be provided adjacent to the oil drain part  148 . 
     The suction and discharge tank  120  is connected to one side of the first suction muffler part  130 . For example, the first suction muffler part  130  and the suction and discharge tank  120  can be integrally formed. 
     The discharge mufflers  150  and  160  can be provided in opposition to each other based on the suction and discharge tank  120 . 
     In detail, the first discharge muffler part  150  of the discharge muffler can be spaced apart from one side of the first suction muffler part  130 . The suction and discharge tank  120  having the suction space “S” and the discharge space “D” are mounted between the first suction muffler part  130  and the first discharge muffler part  150 . 
     The first suction muffler part  130 , the suction and discharge tank  120 , and the first discharge muffler part  150  can be integrally configured. The first suction muffler part  130 , the suction and discharge tank  120 , and the first discharge muffler part  150  can be collectively named a “tank assembly.” 
     The first suction muffler part  130 , the suction and discharge tank  120 , and the first discharge muffler part  150  can be formed of the same material, for example, of a nylon material having higher pressure resistance. 
     The suction and discharge tank  120  can include a tank body  121  having a suction and discharge space. For example, the tank body  121  can have a cylindrical shape. 
     A suction chamber  123   a  and a discharge chamber  123   b  can be formed inside the tank body  121 . The suction chamber  123   a  can have the suction space “S,” and the discharge chamber  123   b  can have the discharge space “D” 
     The suction chamber  123   a  and the discharge chamber  123   b  can be formed to be recessed in a surface facing the valve assembly. 
     The suction chamber  123   a  can be configured to communicate with the suction guide hole  136  of the first suction muffler part  130 . The suction guide hole  136  can be formed in the connection part between the suction and discharge tank  120  and the first suction muffler part  130 . For example, the suction guide hole  136  can be formed in one side of an outer circumferential surface of the suction and discharge tank  120 . 
     The discharge chamber  123   b  can be configured to communicate with the discharge guide hole  156  of the first discharge muffler part  150 . The discharge guide hole  156  can be formed in the connection part between the suction and discharge tank  120  and the first discharge muffler part  150 . For example, the discharge guide hole  156  can be formed in an opposite side of an outer circumferential surface of the suction and discharge tank  120 . 
     The suction and discharge tank  120  can include a partition part  122  to partition the inner space of the suction and discharge tank  120  into the suction chamber  123   a  and the discharge chamber  123   b . The valve assembly can be installed at one side of the suction and discharge tank  120 . The valve assembly can include a suction valve to open and close the suction chamber  123   a  and a discharge valve to open and close the discharge chamber  123   b.    
     A retainer  124  can be provided in the discharge chamber  133   b  to limit the opening amount of the discharge valve. The retainer  124  can protrude from the bottom surface of the discharge chamber  133   b  and be disposed adjacent to the discharge guide hole  156 . 
     The suction and discharge tank  120  can further include a sealing protrusion  125  to which a sealing member is coupled. 
     The second discharge muffler part  160  of the discharge muffler can be assembled with the first discharge muffler part  150 , and a discharge space (or a discharge fluid passage) for the refrigerant can be defined inside the first and second discharge mufflers  150  and  160  through the assembling. 
     When viewed based on  FIG. 3 , the first discharge muffler part  150  can be coupled to an upper side of the second discharge muffler part  160 . 
     The first discharge muffler part  150  can include a first muffler body  151  including a discharge guide hole  156 . An end portion of the first muffler body  151  can be open. 
     A first muffler flange  152  coupled to the second discharge muffler part  160  can be provided on the first muffler body  151 . The first muffler flange  152  can be formed to be stepped from the first muffler body  151  such that an outer diameter of the first muffler flange  132  is greater than an outer diameter of the first muffler body  151 . The first muffler flange  152  can be inserted into an open end portion of the second discharge muffler part  160 . 
     The second discharge muffler part  160  can include a second muffler body  161  having a discharge part  165  coupled to the discharge hose  60 . 
     The first muffler body  151  of the first discharge muffler part  150  and the second muffler body  161  of the second discharge muffler part  160  can be collectively named a “discharge muffler body.” 
     A second muffler flange  162 , which is coupled to the first discharge muffler part  150 , can be provided on an end portion of the second muffler body  161 . The second muffler flange  162  can be formed to be stepped from the second muffler body  161  such that an outer diameter of the second muffler flange  162  is greater than an outer diameter of the second muffler body  161 . The second muffler flange  162  can be coupled to an outer portion of the first muffler flange  152 . 
     A discharge guide device or discharge guide  300  for reducing pressure pulsation of the discharged refrigerant can be provided inside the discharge mufflers  150  and  160 . The discharge guide device  300  can form the discharge fluid passage of the refrigerant, and can be supported by inner surfaces of the discharge mufflers  150  and  160 . The discharge guide  300  can include one or more pipes, tubes, or the like. 
     The discharge hose  60  can extend from the second discharge muffler part  160  and be coupled to the discharge pipe  13 . The discharge hose  60  can be coupled to the discharge part  165   
       FIG. 6  is a view illustrating an example of a suction and discharge tank that is integrated with first and third mufflers. 
     Referring to  FIG. 6 , the muffler assembly  110  can include a tank assembly. For example, the tank assembly can include the suction and discharge tank  120 , the first suction muffler part  130  provided at one side of the suction and discharge tank  120 , and the first discharge muffler part  150  provided at an opposite side of the suction and discharge tank  120 . 
     The first suction muffler part  130  and the first discharge muffler part  150  can be disposed in opposition to each other based on the suction and discharge tank  120 . 
     The first suction muffler part  130  can include a first muffler body  131  to form a flowing space (that is, the suction fluid passage) for the refrigerant which is suctioned into the muffler assembly  110 . The suction guide hole  136 , which is to suction the refrigerant into the suction and discharge tank  120 , can be formed in the first muffler body  131 . The suction guide hole  136  can be formed in a part at which the first suction muffler part  130  is connected with the suction and discharge tank  120 . 
     The first suction muffler part  130  can further include an inner wall  133  provided inside the first muffler body  131 . The inner wall  133  can extend along an inner circumferential surface of the first muffler body  131  in parallel to the first muffler body  131 . 
     The inner wall  133  can be spaced apart from the inner circumferential surface of the first muffler body  131 . An insertion space  134  can be provided between the first muffler body  131  and the inner wall  133 . An end portion of the second suction muffler part  140  can be inserted into the insertion space  134 , such that the first and second suction mufflers  130  and  140  can be assembled. 
     The first discharge muffler part  150  can include a first muffler body  151  that forms a flowing space (that is, a discharge fluid passage  150   a ) for the refrigerant discharged from the suction and discharge tank  120 . The discharge guide hole  156 , which is to discharge the refrigerant from the suction and discharge tank  120 , can be formed in the first muffler body  151 . The discharge guide hole  156  can be formed in a part at which the first discharge muffler part  150  is connected with the suction and discharge tank  120 . 
     The first discharge muffler part  150  can include at least one wall (see reference numerals  153 ,  154 , and  155 ) provided in the discharge fluid passage  150   a  to divide the discharge fluid passage  150   a  into a plurality of discharge rooms. 
     In detail, the discharge muffler bodies  151  and  161 , the walls  153 ,  154  and  155 , and the discharge guide device  300  can define an inner space of the discharge muffler, which is to be divided into a plurality of discharge rooms. 
     The walls  153 ,  154 , and  155  can be provided to protrude from the inner circumferential surface of the first discharge muffler part  150 . For example, the walls  153 ,  154 , and  155  can extend in the vertical direction when viewed based on  FIG. 11 . 
     The at least one wall can include a plurality of walls  153 , 154 , and  155   
     The plurality of walls  153 ,  154 , and  155  can function as “reinforcing walls” that prevent the discharge mufflers  150  and  160  from being damaged by the high pressure applied when the discharged refrigerant flows. 
     The plurality of walls  153 ,  154 , and  155  can include a first wall  153 , a second wall  154  spaced apart from one side of the first wall  153 , and a third wall  155  spaced apart from an opposite side of the first wall  153 . The second and third walls  154  and  155  can be provided on opposite sides of the first wall  153 . 
     The first to third walls  153 ,  154 , and  155  can function as reinforcing walls to prevent the discharge mufflers  150  and  160  from being damaged under a higher-pressure environment of the discharge mufflers  150  and  160 . 
     The discharge chamber  123   b  of the suction and discharge tank  120  can form a primary discharge room “DR 1 ” for the refrigerant (see  FIG. 11 ). 
     A space between the first wall  153  and the first muffler body  151  can form a secondary discharge room “DR 2 ” for the refrigerant (see  FIG. 11 ). 
     A space between the second wall  154  and the first muffler body  151  can form a tertiary discharge room for the refrigerant. In detail, the space formed by the second wall  154  and the discharge muffler bodies  151  and  161  can be defined as the tertiary discharge room “DR 3 ” for the refrigerant (see  FIG. 11 ). 
     A space between the first wall  153  and the second wall  154  can form a quaternary discharge room for the refrigerant. In detail, the space formed by the first and second walls  153  and  154 , the discharge muffler bodies  151  and  161 , and the discharge guide device  300  can define the quaternary discharge room “DR 4 ” (see  FIG. 11 ) for the refrigerant. 
     The discharge guide device  300  can be arranged to be positioned in the spaces among the plurality of walls  153 ,  154 , and  155 . A main stream of the refrigerant discharged to the first discharge muffler part  150  through the discharge guide hole  156  passes through an inner fluid passage of the discharge guide device  300  and is discharged to the outside through the discharge part  165  of the second discharge muffler part  160 . 
     In some implementations, a sub-stream of the refrigerant discharged to the first discharge muffler part  150  through the discharge guide hole  156  can be diffused into the secondary discharge room to the quaternary discharge room. The discharge pulsation of the refrigerant can be reduced by the main stream and the sub-stream of the refrigerant. 
     A second suction muffler part  140  can be assembled to the first suction muffler part  130 . The second suction muffler part  140  can include a second muffler body  141  that forms a suction space for the refrigerant. 
     An assembly end portion  147  inserted into the insertion space  134  of the first suction muffler part  130  can be formed in the second muffler body  141 . The assembly end portion  147  can be formed at an upper end portion of the second muffler body  141 . 
     In some implementations, the end portion of the first suction muffler part  130  is placed on protrusion parts  215   a  and  215   b  of a suction guide device  200 . Accordingly, when the first and second suction mufflers  130  and  140  are assembled, the first suction muffler parts  130  can press the upper end portion of the protrusion parts  215   a  and  215   b . Accordingly, the suction guide device  200  can be stably supported by inner parts of the first and second suction mufflers  130  and  140   
     The suction guide device  200  can include a partition wall  210  to partition the inner space of the suction mufflers  130  and  140  into two spaces, and a guide pipe  220  forming a resonance hole  225  while extending in a direction of crossing the partition wall  210 . The suction fluid passage for the refrigerant can be formed inside the guide pipe  220 . 
     Hereinafter, the configuration and the mounting structure of the discharge guide device will be described with reference to accompanying drawings. 
       FIG. 7  is a perspective view illustrating an example of a second discharge muffler part coupled to a discharge guide device, and  FIG. 8  is an exploded perspective view illustrating the second discharge muffler part and the discharge guide device.  FIG. 9  is a perspective view illustrating an example configuration of the discharge guide device, and  FIG. 10  is a perspective view illustrating an example configuration of the discharge guide device.  FIG. 11  is a cross sectional view taken along line  11 - 11 ′ of  FIG. 3 . 
     Referring to  FIGS. 7 to 11 , the second discharge muffler part  160  can be assembled to the first discharge muffler part  150 . The first discharge muffler part  150  and the second discharge muffler part  160  can be coupled to each other through laser fusion. Accordingly, the coupling status of the discharge mufflers  150  and  160  forming the high-pressure environment can be firmly maintained. 
     The second discharge muffler part  160  can include a second muffler body  161  and a second muffler flange  162  that form a discharge fluid passage  160   a  for the refrigerant. The second muffler flange  162  can be coupled to an outer portion of the first muffler flange  152 . 
     The second discharge muffler part  160  can further include an inner wall  163  provided inside the second muffler body  161 . The inner wall  163  can extend along an inner circumferential surface of the second muffler body  161  in parallel to the second muffler body  161 . 
     The inner wall  163  can be spaced apart from the inner circumferential surface of the second muffler body  161 . An insertion space  164  can be provided between the second muffler body  161  and the inner wall  163 . An end portion of the first discharge muffler part  150  is inserted into the insertion space  164 , such that the first and second discharge mufflers  150  and  160  can be assembled. 
     A portion of the discharge guide device  300  can be supported by the upper end portion of the inner wall  163 . 
     The second discharge muffler part  160  can further include an inner wall  163  provided to be stepped at an inside of the second muffler body  161 . Another portion of the discharge guide device  300  can be supported by the upper end portion of the wall protrusion part  167 . The upper end portion of the wall protrusion part  167  can be formed at a lower position than that of the upper end portion of the inner wall  163 . 
     The inner wall  163  and the wall protrusion part  167  can be understood as components including a “first jaw” and a “second jaw,” respectively, in that the inner wall  163  and the wall protrusion part  167  support the discharge guide device  300 . 
     The discharge guide device  300  can be supported by the second discharge muffler part  160 . 
     The discharge guide device  300  can be seated on a bottom surface of the second discharge muffler part  160 . 
     The discharge guide device  300  can include a pipe  310  in which a fluid passage  312  (see  FIG. 11 ; the inner fluid passage) for the refrigerant discharged to the discharge mufflers  150  and  160  is formed. 
     The pipe  310  can have a bending shape to guide the refrigerant, which is positioned at the upper side of the discharge mufflers  150  and  160 , to the discharge part  165  positioned at the lower side of the discharge mufflers  150  and  160 . 
     The pipe  310  can include a first pipe part  311  extending toward the discharge part  165  from the discharge guide hole  156  of the discharge mufflers  150  and  160 . For example, the first pipe part  311  can extend in the vertical direction when viewed based on  FIG. 7 . 
     The first pipe part  311  can include a pipe inflow hole  311   a  to introduce the refrigerant, which is introduced into the discharge mufflers  150  and  160  through the discharge guide hole  156 , into the pipe  310 . The pipe inflow hole  311   a  can be formed in an end portion of the first pipe part  311 , and can be disposed toward the discharge guide hole  156 . 
     The pipe inflow hole  311   a  can be formed at a position closest to the discharge guide hole  156  of components of the discharge guide device  300 . 
     The pipe  310  can include a second pipe part  315  bent from the first pipe part  311  to extend toward the discharge part  165 . For example, the second pipe part  315  can extend in the horizontal direction when viewed based on  FIG. 7 . 
     The second pipe part  315  can include a pipe outflow hole  315   a  to discharge the refrigerant from the pipe  310 . The pipe outflow hole  315   a  can be formed in an end portion of the second pipe part  315 , and can be disposed toward the discharge part  165 . 
     The pipe outflow hole  315   a  can be formed at a position closest to the discharge part  165  of components of the discharge guide device  300 . 
     The refrigerant can be introduced into the first pipe part  311  through the pipe inflow hole  311   a , can flow through the second pipe part  315 , and can be discharged from the second pipe part  315  through the pipe outflow hole  315   a.    
     The discharge guide device  300  can further include a fixing bracket  330  to support the pipe  310  with respect to the discharge mufflers  150  and  160 . For example, the fixing bracket  330  can be provided at an outer portion the second pipe part  315 . In other words, the fixing bracket  330  can surround a portion of the outer circumferential surface of the second pipe part  315 . 
     The discharge guide device  300  can further include a first pipe connection part  340  to connect the first pipe part  311  to the fixing bracket  330 . The first pipe part  311 , the fixing bracket  330 , and the first pipe connection part  340  can be integrally formed with each other. 
     The first pipe connection part  340  can be interposed between the first pipe part  311  and the fixing bracket  330 . The supporting status of the first pipe part  311  with respect to the discharge mufflers  150  and  160  can be firmly maintained through the first pipe connection part  340 . 
     The discharge guide device  300  can further include a second pipe connection part  350  to connect the second pipe part  315  to the fixing bracket  330 . The second pipe part  315 , the fixing bracket  330 , and the second pipe connection part  350  can be integrally formed with each other. 
     The second pipe connection part  350  can be provided on a side surface of the second pipe part  315 . In other words, the second pipe connection part  350  can be provided on an outer circumferential surface of the second pipe part  315 . The supporting status of the second pipe part  315  with respect to the discharge mufflers  150  and  160  can be firmly maintained through the second pipe connection part  350 . 
     The fixing bracket  330  can include a bracket body  331  having an insertion groove  338  into which the walls  153 ,  154 , and  155  are inserted. The first and second pipe connection parts  340  and  350  can be provided at opposite sides of the bracket body  331 . 
     The insertion groove  338  can be formed to be recessed downward from the top surface of the fixing bracket  330 . For example, the first wall  153  can be inserted into the insertion groove  338 . 
     As the first wall  153  is inserted into the insertion groove  338 , the inner space of the discharge mufflers  150  and  160  can be partitioned by the first wall  153  and the discharge guide device  300 . For example, the first wall  153  and the discharge guide device  300  can act to separate the secondary discharge room “DR 2 ” and the quaternary discharge room “DR 4 ” from each other. 
     The second wall  154  can be disposed adjacent to an upper portion of the second pipe part  315  or disposed in contact with the second pipe part  315   
     The second pipe part  315  and the second wall  154  do not completely separate the tertiary discharge room “DR 3 ” from the quaternary discharge room “DR 4 ,” and the tertiary discharge room “DR 3 ” and the quaternary discharge room “DR 4 ” can communicate with each other through the surrounding space of the second pipe part  315 . 
     The bracket body  331  can be supported by the second discharge muffler part  160 . In detail, the bracket body  331  can include stepwise sections  333  and  335  supported by the second discharge muffler part  160 . 
     The stepwise sections  333  and  335  can include a first stepwise section  333  supported by the inner wall  163  of the second discharge muffler part  160 . The first stepwise section  333  can be stepped in a direction, in which the width of the bracket body  331  is reduced, from the outer surface of the bracket body  331 . 
     The stepwise sections  335  and  335  can include a second stepwise section  333  supported by the wall protrusion part  167  of the second discharge muffler part  160 . The second stepwise section  335  can be stepped in a direction, in which the width of the bracket body  331  is reduced, from the outer surface of the first stepwise section  333 . Accordingly, the width of the second stepwise section  335  can be narrower than the width of the first stepwise section  333 . 
     The first stepwise section  333  can be positioned above the second stepwise section  335 , corresponding to that the inner wall  163  is positioned above the wall protrusion part  167 . 
     Hereinafter, the procedure of assembling the discharge guide device  300  with the discharge mufflers  150  and  160  will be described in brief. 
     The first wall  153  is inserted into the insertion groove  338  of the discharge guide device  300 , thereby assembling the discharge guide device  300  with the first discharge muffler part  150 . Then, the second discharge muffler part  160  is assembled with the first discharge muffler part  150  such that the discharge guide device  300  is seated on the second discharge muffler part  160 . The first and second discharge mufflers  150  and  160  are firmly coupled to each other by laser fusion. 
       FIG. 12  is a view illustrating an example of a refrigerant flow in the discharge muffler. Hereinafter, a refrigerant discharging action in the discharging mufflers  150  and  160  will be described in brief with reference to  FIGS. 11 and 12  together. 
     When the reciprocating compressor  1  starts to drive, the refrigerant is introduced into the shell  10  through the suction pipe  12 , and introduced into the suction mufflers  130  and  140  through the suction hole  142 . 
     The refrigerant can be introduced into the second suction muffler part  140 , and can flow through the guide pipe  220 . In this case, a portion of the refrigerant is diffused into the inner space of the suction mufflers  130  and  140  through the resonance hole  225 , and noise of the suctioned refrigerant can be reduced. 
     The refrigerant suctioned into the suction mufflers  130  and  140  is compressed in the cylinder  33  via the suction chamber  123   a  of the suction and discharge tank  120 , and the compressed higher-pressure gas refrigerant can be discharged to the discharge mufflers  150  and  160  through the discharge chamber  123   b  of the suction and discharge tank  120  and the discharge guide hole  156 . 
     The discharge chamber  123   b  can have the primary discharge room “DR 1 ” for the refrigerant. 
     The main stream (marked with a solid arrow) of the refrigerant introduced into the discharge mufflers  150  and  160  can be introduced into the pipe  310  through the pipe inflow hole  311   a . The refrigerant can be discharged through the pipe outflow hole  315   a  via the first pipe part  311  and the second pipe part  315 . 
     The pressure pulsation can be reduced in the procedure in which the refrigerant flows through the first and second pipe parts  311  and  315 . 
     The refrigerant can be discharged through the discharge part  165  of the discharge mufflers  150  and  160 , and can flow through the discharge hose  60 . 
     The secondary discharge room “DR 2 ” can be formed inside the discharge mufflers  150  and  160 . The secondary discharge chamber “DR 2 ” can be defined as an external space of the discharge guide device  300 , of spaces formed by the first wall  153  and the discharge muffler bodies  151  and  161 . 
     The secondary discharge chamber “DR 2 ” can be separated from the quaternary discharge room “DR 4 ” by the first wall  153  and the discharge guide device  300   
     A sub-stream (marked with a dotted arrow) of the discharge refrigerant other than the main stream can be diffused into the secondary discharge room “DR 2 .” 
     The tertiary discharge room “DR 3 ” can be formed inside the discharge mufflers  150  and  160 . The tertiary discharge room “DR 3 ” can include a space defined by the second wall  154  and the discharge muffler bodies  151  and  161 . The sub-stream of the refrigerant other than the main stream, which is discharged through the pipe outflow hole  315   a  of the pipe  310 , can be spread into the tertiary discharge room “DR 3 .” 
     The quaternary discharge room “DR 4 ” can be formed inside the discharge mufflers  150  and  160 . The quaternary discharge room “DR 4 ” can include a space defined by the first and second walls  153  and  154 , the discharge muffler bodies  151  and  161 , and the discharge guide device  300 . 
     The quaternary discharge room “DR 4 ” can communicate with the tertiary discharge room “DR 3 .” The communicating space can be a surrounding space (a front-rear space when viewed from the drawing) of the second pipe part  315 . 
     The sub-stream of the refrigerant other than the main stream, which is discharged through the pipe outflow hole  315   a  of the pipe  310 , can be spread into the quaternary discharge room “DR 4 ” through the tertiary discharge room “DR 3 .” 
     As described above, the refrigerant introduced into the discharge mufflers  150  and  160  has the main stream into the pipe  310  and sub-streams into the secondary discharge room “DR 2 ” to the quaternary discharge room “DR 4 .” In this procedure, the pressure pulsation can be reduced. 
       FIG. 13  is a graph illustrating an example of an experimental result showing an effect of reducing a pulsation with the discharge muffler having the discharge guide device. Specifically,  FIG. 13  illustrates the comparison between a related art and the present disclosure in terms of the intensity of sound pressure generated in a frequency range having a specific band. The frequency range having the specific band shows 2,000 Hz or less. 
     The related art relates to a technology of using a discharge muffler without a discharge guide device, and the present disclosure relates to a technology in which the discharge guide device  300  described above is provided inside the discharge mufflers  150  and  160 . 
     The intensity of the sound pressure generated from the discharge muffler according to the present disclosure can be lower than the intensity of the sound pressure generated from the discharge muffler according to the related art, throughout the whole frequency range. 
     According to the experimental result, as the discharge guide device is provided in the discharge muffler according to the preset disclosure, the pressure pulsation of the discharged refrigerant can be reduced.