KR102458151B1 - Linear compressor - Google Patents

Abstract

A linear compressor is provided. A linear compressor according to an aspect of the present specification includes a cylinder; a piston reciprocating in the axial direction within the cylinder; a first muffler unit coupled to the piston and forming a first refrigerant passage; a back cover including a first opening formed in a radially central region and disposed behind the piston; and a second muffler unit coupled to the rear of the back cover. In this case, the first muffler unit includes an inner guide disposed inside the piston, a first suction muffler disposed behind the inner guide, and a rear side of the first suction muffler and passing through the first opening. and a first extension, wherein the second muffler unit includes a second suction muffler communicating with the first extension and a second radially outer side of the second suction muffler and communicating with the second suction muffler. including extensions.

Description

Linear compressor {LINEAR COMPRESSOR}

This specification relates to a linear compressor. More particularly, it relates to a linear compressor that compresses a refrigerant by a linear reciprocating motion of a piston.

In general, a compressor refers to a device configured to compress a working fluid such as air or refrigerant by receiving power from a power generating device such as a motor or a turbine. Specifically, the compressor is widely applied to the entire industry or home appliances, in particular, a vapor compression refrigeration cycle (hereinafter referred to as a 'refrigeration cycle').

Such a compressor may be classified into a reciprocating compressor, a rotary compressor (rotary compressor), and a scroll compressor according to a method of compressing the refrigerant.

In the reciprocating compressor, a compression space is formed between the piston and the cylinder and the piston moves in a linear reciprocating motion to compress the fluid. It is a method of compressing the fluid by rotating a pair of scrolls in engagement.

Recently, among reciprocating compressors, the use of a linear compressor using a linear reciprocating motion without using a crankshaft is gradually increasing. The linear compressor has advantages in that the efficiency of the compressor is improved because the mechanical loss involved in converting the rotational motion into a linear reciprocating motion is small, and the structure is relatively simple.

The linear compressor is configured such that a cylinder is positioned inside a casing forming a closed space to form a compression chamber, and a piston covering the compression chamber reciprocates within the cylinder. In a linear compressor, when the piston is positioned at the bottom dead center (BDC), the fluid in the enclosed space is sucked into the compression chamber, and when the piston is positioned at the top dead center (TDC, top dead center), the fluid in the compression chamber is The process of being compressed and discharged is repeated.

A compression unit and a driving unit (motor) are respectively installed inside the linear compressor, and the compression unit performs a process of compressing and discharging refrigerant while reciprocating in the axial direction through movement generated in the driving unit.

The piston of the linear compressor sucks the refrigerant into the casing through the suction pipe while reciprocating at high speed inside the cylinder by the resonance spring, and then is discharged from the compression space by the forward movement of the piston, and the discharged refrigerant is discharged from the discharge pipe A series of processes moving to the condenser are repeatedly performed.

Meanwhile, noise is generated while the piston continuously sucks, compresses, and discharges the refrigerant while reciprocating inside the cylinder. In order to reduce the noise generated in this way, a muffler is installed in the conventional linear compressor. The muffler includes an insertion portion inserted into the piston, a silencer disposed axially rearward of the insertion portion and having a larger inner diameter than the insertion portion, and an extension portion extending axially rearward from the silencer.

In the muffler, the insertion part is fixedly inserted into the gas flow path of the piston and coupled to the piston, and the extension part is positioned on the same line as the suction pipe coupled to the casing. Such a muffler reciprocates immediately before the piston as it reciprocates in a straight line, and the refrigerant sucked into the suction pipe flows into the piston through the extension part, the silencer, and the insertion part. And the noise generated in the compression space formed by the cylinder and the piston is attenuated in the process of going through the muffler through the piston.

Such a linear compressor is disclosed in Korean Patent Publication No. 10-0314064 B (hereinafter, Prior Art 1).

Meanwhile, in a typical refrigerator, a compressor, a suction pipe, and a cooling fan are sequentially arranged from the front in the axial direction. Referring to FIG. 11 , in the conventional linear compressor, the suction pipe 314 is coupled to the rear surface of the casing 110 , that is, the first shell cover 312 . Therefore, since the suction pipe installation space G2 in which the suction pipe 314 can be disposed between the casing 110 and the cooling fan PAN is required, the space utilization inside the refrigerator machine room is reduced, and the There is a problem that the cooling efficiency is lowered.

In addition, the natural sound field frequency inside the casing of the compressor filled with the suction refrigerant is inversely proportional to the casing length in each direction. In general, since the length of the casing of the linear compressor is long in the axial direction and short in the radial direction, the axial resonance noise has a low frequency, and the radial resonance noise has a high frequency. Referring to FIG. 12 , in the conventional linear compressor, the pressure fluctuation sound is most strongly radiated in the axial direction along the extension of the muffler. Accordingly, there was also a problem in that the low-frequency resonance noise in the range of 300 to 400 Hz, which is the natural sound field frequency in the axial direction, was generated the most.

Korean Patent Publication No. 10-0314064 B (2015.01.20. Announcement)

An object of the present specification is to provide a linear compressor capable of increasing space efficiency by reducing an installation space of a suction pipe formed at the rear of a casing, and improving compressor cooling efficiency by a cooling fan.

Another object of the present invention is to provide a linear compressor capable of reducing low-frequency resonance noise generated due to a structure of a linear compressor extending in an axial direction.

A linear compressor according to an aspect of the present specification for achieving the above object includes: a cylinder; a piston reciprocating in the axial direction within the cylinder; a first muffler unit coupled to the piston; a back cover including a first opening formed in a radially central region and disposed behind the piston; and a second muffler unit coupled to the rear of the back cover.

In this case, the first muffler unit includes an inner guide disposed inside the piston, a first suction muffler disposed behind the inner guide, and a rear side of the first suction muffler and passing through the first opening. and a first extension, wherein the second muffler unit includes a second suction muffler communicating with the first extension and a second radially outer side of the second suction muffler and communicating with the second suction muffler. It may include an extension.

Through this, it is possible to increase the space efficiency by reducing the installation space of the suction pipe formed at the rear of the casing, and to increase the cooling efficiency of the compressor by the cooling fan.

In addition, it is possible to reduce the low-frequency resonance noise generated due to the structure of the linear compressor formed long in the axial direction.

In addition, a second noise space may be formed between the second suction muffler and the rear surface of the back cover, and the rear end of the first extension may reciprocate in the axial direction within the second noise space.

In addition, the second extension part may be in close contact with the back cover, and a second flow path communicating with the second noise space may be formed between the back cover and the second extension part.

In addition, the second opening formed in the second extension portion may be disposed in front of the second suction muffler.

The second extension portion may include a vertical portion communicating with the second suction muffler and extending radially outward, and a horizontal portion communicating with the vertical portion and extending forward.

Also, the second muffler unit may include a second opening, and the second opening may radially overlap the first muffler unit.

Also, an inner circumferential surface of the first opening may be adjacent to an outer circumferential surface of the first extension portion.

In addition, a radial length of the inner surface of the second suction muffler may be greater than an inner diameter of the first extension.

In addition, a cross-sectional area of the passage of the second suction muffler may be greater than a cross-sectional area of the passage of the second extension.

In addition, the casing for accommodating the cylinder; a rear elastic member having one end connected to the casing and the other end connected to the back cover; and a fixing member for fixing the second muffler unit to the back cover.

In this case, the second muffler unit includes a fixing part extending outwardly from the second suction muffler, the fixing member passing through the fixing part and coupled to the back cover, and the other end of the rear elastic member is It may be disposed between the fixing part and the back cover.

In addition, the casing for accommodating the cylinder; and a suction pipe passing through the casing in a radial direction and supplying a refrigerant to the second muffler unit.

In addition, the second muffler unit may include a second opening formed in the second extension, and one end of the suction pipe may face the second opening.

In addition, a nozzle part disposed between the second opening part and the suction pipe may be included, and a radially inner radius of the nozzle part may be smaller than a radially outer radius of the nozzle part.

Also, the second muffler unit may include a connection auxiliary part protruding outwardly of the second opening, and the radially inner side of the nozzle part may be press-fitted to the connection auxiliary part.

A linear compressor according to another aspect of the present specification for achieving the above object includes: a cylinder; a piston reciprocating in the axial direction within the cylinder; and a muffler unit forming a flow path of the refrigerant supplied to the piston.

In this case, the flow path may include a first flow path extending rearward from the inside of the piston, and a second flow path extending radially outward from the first flow path.

In addition, a second noise space is provided between the first flow path and the second flow path, wherein a radial length of the second noise space is greater than a radial length of the first flow path, and the second noise space A flow passage cross-sectional area of may be greater than a flow passage cross-sectional area of the second flow passage.

In addition, a portion of the second flow path may extend forward in a radial direction outside the first flow path.

The muffler unit may include a first muffler unit forming the first flow path and a second muffler unit forming the second flow path, the first muffler unit being coupled to the piston, and the first muffler unit being coupled to the piston. The rear end of the unit may reciprocate in the axial direction inside the second muffler unit.

In addition, the casing for accommodating the cylinder; and a suction pipe passing through the side surface of the casing and supplying a refrigerant to the second flow path.

Through the present specification, it is possible to increase the space efficiency by reducing the installation space of the suction pipe formed at the rear of the casing, and to increase the cooling efficiency of the compressor by the cooling fan.

In addition, it is possible to reduce the low-frequency resonance noise generated due to the structure of the linear compressor formed long in the axial direction.

1 is a perspective view of a linear compressor according to an embodiment of the present specification.
2 is a cross-sectional view of a linear compressor according to an embodiment of the present specification.
Figure 3 is a rear view of the linear compressor according to an embodiment of the present specification with the first shell cover removed.
4 is a perspective view of a partial configuration of a linear compressor according to an embodiment of the present specification.
5 is a cross-sectional view of a partial configuration of a linear compressor according to an embodiment of the present specification.
6 is an exploded perspective view of a partial configuration of a linear compressor according to an embodiment of the present specification.
7 is a perspective view of a second muffler unit of the linear compressor according to an embodiment of the present specification.
8 is a cross-sectional view of a partial configuration of a linear compressor according to another embodiment of the present specification.
9 is a perspective view of a second muffler unit of a linear compressor according to another embodiment of the present specification.
10 is a side view of a linear compressor according to an embodiment of the present specification.
11 is a side view of a linear compressor according to the prior art.
12 is a graph showing the magnitude (dB) of the resonance noise for each frequency (Hz) generated when the linear compressor according to the prior art is started.

Hereinafter, the embodiments disclosed in the present specification (discloser) will be described in detail with reference to the accompanying drawings, but the same or similar components are given the same reference numerals regardless of reference numerals, and redundant description thereof will be omitted.

In the description of the embodiments disclosed herein, when a component is referred to as being “connected” or “connected” to another component, it may be directly connected or connected to the other component, It should be understood that other components may exist in between.

In addition, in describing the embodiments disclosed in the present specification, if it is determined that detailed descriptions of related known technologies may obscure the gist of the embodiments disclosed in the present specification, the detailed description thereof will be omitted. In addition, the accompanying drawings are only for easy understanding of the embodiments disclosed in the present specification, and the technical spirit disclosed in this specification is not limited by the accompanying drawings, and all changes included in the spirit and scope of the present specification , should be understood to include equivalents or substitutes.

On the other hand, the terms of the specification (discloser) can be replaced with terms such as document, specification, description.

1 is a perspective view of a linear compressor 100 according to an embodiment of the present specification.

Referring to FIG. 1 , the linear compressor 100 according to an embodiment of the present specification may include a casing 110 . The casing 110 may include a shell 111 and shell covers 112 and 113 coupled to the shell 111 . In a broad sense, the shell covers 112 and 113 may be understood as one configuration of the shell 111 .

The lower side of the shell 111, the leg 20 may be coupled. The leg 20 may be coupled to the base of the product on which the linear compressor 100 is installed. For example, the product may include a refrigerator, and the base may include a machine room base of the refrigerator. As another example, the product may include the outdoor unit of the air conditioner, and the base may include the base of the outdoor unit.

The shell 111 has a substantially cylindrical shape, and may form an arrangement lying in a transverse direction or an arrangement lying in an axial direction. Referring to FIG. 1 , the shell 111 extends long in the horizontal direction, and may have a rather low height in the radial direction. That is, since the linear compressor 100 may have a low height, for example, when the linear compressor 100 is installed in the machine room base of the refrigerator, there is an advantage that the height of the machine room can be reduced.

In addition, the longitudinal central axis of the shell 111 coincides with the central axis of the main body of the linear compressor 100 to be described later, and the central axis of the main body of the linear compressor 100 is the cylinder 140 constituting the main body of the linear compressor 100 . ) and coincides with the central axis of the piston 150 .

The terminal 30 may be installed on the outer surface of the shell 111 . The terminal 30 may transmit external power to the driving unit 130 of the linear compressor 100 . Specifically, the terminal 30 may be connected to a lead wire of the coil 132b.

A bracket 31 may be installed on the outside of the terminal 30 . The bracket 31 may include a plurality of brackets surrounding the terminal 30 . The bracket 31 may function to protect the terminal 30 from an external impact.

Both sides of the shell 111 may be open. Shell covers 112 and 113 may be coupled to both sides of the opened shell 111 . Specifically, the shell covers 112 and 113 include a first shell cover 112 coupled to one open side of the shell 111 and a second shell cover 113 coupled to the other open side of the shell 111 . ) may be included. The inner space of the shell 111 may be sealed by the shell covers 112 and 113 .

Referring to FIG. 1 , the first shell cover 112 may be located on the right side of the linear compressor 100 , and the second shell cover 113 may be located on the left side of the linear compressor 100 . In other words, the first and second shell covers 112 and 113 may be disposed to face each other. In addition, it may be understood that the first shell cover 112 is located on the suction side of the refrigerant, and the second shell cover 113 is located on the discharge side of the refrigerant.

The linear compressor 100 is provided on the shell 111 or the shell covers 112 and 113 and may include a plurality of pipes 114 , 115 , and 40 capable of sucking, discharging, or injecting refrigerant.

A plurality of pipes (114, 115, 40) is a suction pipe (114) so that the refrigerant is sucked into the interior of the linear compressor (100), and a discharge pipe (115) so that the compressed refrigerant is discharged from the linear compressor (100), It may include a replenishment pipe 40 for replenishing the refrigerant to the linear compressor 100 .

The suction pipe 114 may radially penetrate the casing 110 and supply a refrigerant to the second muffler unit 190 . Specifically, the suction pipe 114 may supply the refrigerant to the second flow path 106 formed in the second extension 192 of the second muffler unit 190 . In this case, the suction pipe 114 may pass through the casing 110 at a location corresponding to the location of the second opening 193 formed in the second muffler unit 190 inside the casing 110 .

When the casing 110 includes a cylindrical shell 111 having both ends open, and a first shell cover 112 and a second shell cover 113 coupled to both ends of the shell 111, the suction pipe 114 ) may be coupled through the shell 111 in the radial direction. Since the first shell cover 112 is welded to fit into the right opening of the shell 111 , a portion in which the edges of the shell 111 and the first shell cover 112 overlap in a radial direction may be formed. At this time, the suction pipe 114 may be coupled through the shell 111 at a position where the shell 111 and the first shell cover 112 do not overlap.

The discharge pipe 115 may be coupled to the outer peripheral surface of the shell 111 . The refrigerant sucked through the suction pipe 114 may be compressed while flowing in the axial direction. And the compressed refrigerant may be discharged through the discharge pipe (115). The discharge pipe 115 may be disposed at a position closer to the second shell cover 113 than the first shell cover 112 .

Supplement pipe 40 may be coupled to the outer peripheral surface of the shell (111). The operator may inject the refrigerant into the linear compressor 100 through the supplementary pipe 40 .

The supplementary pipe 40 may be coupled to the shell 111 at a different height from the discharge pipe 115 in order to avoid interference with the discharge pipe 115 . Here, the height may be understood as the distance in the vertical direction from the leg 20 . The discharge pipe 115 and the supplementary pipe 40 are coupled to the outer circumferential surface of the shell 111 at different heights, thereby improving work convenience.

At least a portion of the second shell cover 113 may be located adjacent to the inner circumferential surface of the shell 111 corresponding to the point at which the supplementary pipe 40 is coupled. In other words, at least a portion of the second shell cover 113 may act as a resistance of the refrigerant injected through the supplementary pipe 40 .

Accordingly, the size of the flow path of the refrigerant introduced through the supplementary pipe 40 is reduced by the second shell cover 113 as it enters the inner space of the shell 111 , passes therethrough, and becomes larger again. In this process, the pressure of the refrigerant is reduced and the refrigerant may be vaporized, and in this process, the oil contained in the refrigerant may be separated. Accordingly, as the refrigerant from which oil is separated flows into the piston 150 , the compression performance of the refrigerant may be improved. Oil can be understood as the hydraulic fluid present in the cooling system.

2 is a cross-sectional view of the linear compressor 100 according to an embodiment of the present specification. Figure 3 is a rear view of the linear compressor 100 according to an embodiment of the present specification with the first shell cover removed. 4 is a perspective view of a partial configuration of the linear compressor 100 according to an embodiment of the present specification. 5 is a cross-sectional view of a partial configuration of the linear compressor 100 according to an embodiment of the present specification. 6 is an exploded perspective view of a part of the linear compressor 100 according to an embodiment of the present specification. 7 is a perspective view of the second muffler unit 190 of the linear compressor 100 according to an embodiment of the present specification.

Hereinafter, the compressor according to the present specification will be described as an example of a linear compressor 100 in which the piston 150 performs an operation of sucking and compressing a fluid while linearly reciprocating, and discharging the compressed fluid.

The linear compressor 100 according to an embodiment of the present specification includes a cylinder 140 , a piston 150 , a muffler unit 160 , 190 , a spring supporter 119 , a resonance spring 118 , and a magnet The frame 136 and the mover 135 may be included, but may be implemented except for some of these configurations, and additional configurations are not excluded.

The detailed configuration of the linear compressor 100 according to an embodiment of the present specification according to FIGS. 4 to 8, which is not described below, is the same as the detailed configuration of the linear compressor 100 according to an embodiment of the present specification according to FIG. 3 . can be understood as

The linear compressor 100 may be a component of a refrigeration cycle, and the fluid compressed in the linear compressor 100 may be a refrigerant circulating in the refrigeration cycle. The refrigeration cycle may include a condenser, an expansion device and an evaporator in addition to the compressor. In addition, the linear compressor 100 may be used as one component of the cooling system of the refrigerator, and is not limited thereto, and may be widely used throughout the industry.

Referring to FIG. 2 , the linear compressor 100 may include a casing 110 and a body accommodated in the casing 110 . The main body of the linear compressor 100 includes a frame 120 , a cylinder 140 fixed to the frame 120 , a piston 150 reciprocating in the axial direction in the cylinder 140 , and fixed to the frame 120 . and may include a driving unit 130 and the like for applying a driving force to the piston 150 . Here, the cylinder 140 and the piston 150 may be referred to as compression units 140 and 150 .

The linear compressor 100 may include bearing means for reducing friction between the cylinder 140 and the piston 150 . The bearing means may be oil bearings or gas bearings. Alternatively, a mechanical bearing may be used as the bearing means.

The main body of the linear compressor 100 may be elastically supported by elastic members 116 and 117 installed inside the casing 110 . The elastic members 116 and 117 may include a rear elastic member 116 supporting the rear of the main body and a front elastic member 117 supporting the front of the main body. The elastic members 116 and 117 may absorb vibrations and shocks generated according to the reciprocating motion of the piston 150 while supporting the internal components of the main body of the linear compressor 100 .

The casing 110 may form an enclosed space. The sealed space includes an accommodation space 101 in which the sucked refrigerant is accommodated, a suction space 102 filled with the refrigerant before being compressed, a compression space 103 that compresses the refrigerant, and a discharge space filled with the compressed refrigerant ( 104) may be included.

A portion of the refrigerant sucked from the suction pipe 114 may be filled in the accommodation space 101 , and the remainder may be introduced into the second muffler unit 190 . The refrigerant flowing into the second muffler unit 190 may move to the compression space 103 along the refrigerant passages 105 and 106 formed inside the first muffler unit 160 and the second muffler unit 190 . . The refrigerant moving into the compression space 103 is compressed by the axial reciprocating motion of the piston 150 and discharged to the discharge space 104 , and is discharged to the outside through the discharge pipe 115 connected to the front side of the casing 110 . can be emitted.

The casing 110 includes a shell 111 having both ends open and formed in a substantially transversely long cylindrical shape, a first shell cover 112 coupled to the rear side of the shell 111, and a second coupled to the front side. It may include a shell cover 113 . Here, the front side may be interpreted to mean a direction in which the compressed refrigerant is discharged to the left of the drawing, and the rear side may be interpreted to mean a direction in which the refrigerant is introduced to the right side of the drawing. In addition, the first shell cover 112 or the second shell cover 113 may be integrally formed with the shell 111 .

The casing 110 may be formed of a thermally conductive material. Through this, heat generated in the inner space of the casing 110 can be quickly radiated to the outside.

The linear compressor 100 may include a rear elastic member 116 . The rear side of the main body of the linear compressor 100 may be elastically supported in the axial direction and/or radial direction by the rear elastic member 116 . The rear elastic member 116 may have one end connected to the casing 110 and the other end connected to the back cover 123 . The rear elastic member 116 may absorb vibration and shock generated according to the reciprocating motion of the piston 150 .

The rear elastic member 116 may be formed as a pair. Referring to FIG. 4 , when viewed from the rear in the axial direction, the pair of rear elastic members 116 may be formed symmetrically left and right, respectively. In this case, the main body can be effectively elastically supported not only in the axial direction but also in the radial direction.

The rear elastic member 116 includes an elastic part 116a having elasticity, a first connection part 116b disposed at one end of the elastic part 116a, and a second connection part 116c disposed at the other end of the elastic part 116a. ) may be included.

One end of the elastic part 116a may be fixed to the first connection part 116b , and the first connection part 116b may be connected to the inner circumferential surface of the casing 110 . In this case, the rear elastic members 116 formed as a pair may share one first connecting portion 116b. Accordingly, one end of the rear elastic member 116 may be connected to the inner circumferential surface of the casing 110 .

The second connection part 116c may be disposed between the back cover 123 and the first fixing part 1961 of the second muffler unit 190 . When the first fixing part 1961 is coupled to the back cover 123 , the second connecting part 116c may also be coupled to the back cover 123 . Accordingly, the other end of the rear elastic member 116 may be coupled to the rear surface of the back cover 123 , and the linear compressor 100 may be elastically supported in the axial direction and/or radial direction by the rear elastic member 116 . .

When the front elastic member 117 is connected to the lower portion of the inner circumferential surface of the casing 110 , the first connecting portion 116b may be preferably connected to the upper portion of the inner circumferential surface of the casing 110 . However, unlike FIG. 3 , when the front elastic member 117 is connected to the upper portion of the inner circumferential surface of the casing 110 , it may be preferable that the first connecting portion 116b is connected to the lower portion of the inner circumferential surface of the casing 110 .

When the front elastic member 117 and the rear elastic member 116 are connected to the lower and upper portions, or upper and lower portions, respectively, on the inner circumferential surface of the casing 110 (that is, connected to each other at a diagonal position when viewed from the side), the piston 150 ) can cancel the rotational moment of the main body caused by the axial reciprocating motion. However, the present invention is not limited thereto, and the second connection portion 116c may be coupled to various positions on the inner circumferential surface of the casing 110 according to the arrangement or shape of the inner configuration of the casing 110 .

The rear elastic member 116 may be formed of a wire spring. The wire spring may be formed by bending a wire having elasticity. At this time, the elastic modulus of the wire spring may be adjusted by adjusting the bending direction, the number of bending times, the bending degree, and the like.

Unlike FIGS. 2 to 7 , the rear elastic member 116 may be formed of various elastic members such as a leaf spring and a coil spring.

The second shell cover 113 may be coupled to the shell 111 to seal the front side of the shell 111 , and the discharge pipe 115 may be inserted through the roof pipe 115a to be coupled thereto. The refrigerant discharged from the compression space 103 may be discharged to the refrigerating cycle through the loop pipe 115a and the discharge pipe 115 after passing through the discharge cover assembly 180 .

The front side of the main body of the linear compressor 100 may be elastically supported in the axial direction and/or radial direction of the shell 111 or the second shell cover 113 by the front elastic member 117 .

The front elastic member 117 may include a circular leaf spring. The opened central portion of the front elastic member 117 may be supported in a rearward direction with respect to the discharge cover assembly 180 by the first support guide 117b. The edge of the front elastic member 117 may be supported in the forward direction with respect to the inner surface of the shell 111 or the inner peripheral surface of the shell 111 adjacent to the second shell cover 113 by the support bracket 117a.

Unlike FIG. 3 , the edge of the front elastic member 117 is adjacent to the inner surface of the shell 111 or the second shell cover 113 through a separate bracket (not shown) coupled to the second shell cover 113 . It may be supported in the forward direction with respect to the inner circumferential surface of the shell 111 .

The first support guide 117b may be formed in a cylindrical shape. A cross-section of the first support guide 117b may include a plurality of diameters. The front side of the first support guide 117b may be inserted into the central opening of the front elastic member 117 , and the rear side may be inserted into the central opening of the discharge cover assembly 180 . The support cover 117c may be coupled to the front side of the first support guide 117b with the front elastic member 117 interposed therebetween. A cup-shaped second support guide 117d concave in the front may be coupled to the front side of the support cover 117c. A cup-shaped third support guide 117e corresponding to the second support guide 117d and recessed rearward may be coupled to the inside of the second shell cover 113 . The second support guide 117d may be inserted inside the third support guide 117e to be supported in the axial direction and/or the radial direction. In this case, a gap may be formed between the second support guide 117d and the third support guide 117e.

The linear compressor 100 may include a back cover 123 . The back cover 123 may include a back plate part 123a, a bridge part 123b, and a first opening 123c. The back cover 123 may be elastically supported in the axial direction and/or radial direction with respect to the casing 110 by the rear elastic member 116 .

The back cover 123 may include a back plate part 123a. The back plate part 123a may be formed to extend outwardly in the radial direction of the first extension part 163 of the first muffler unit 160 . That is, the radial central area of the back plate part 123a may include a first opening 123c through which the first extension part 163 of the first muffler unit 160 passes.

The back cover 123 may include a bridge part 123b. The bridge part 123b may extend forward in the axial direction from the radially outer side of the back plate part 123a. The front end of the bridge part 123b may be coupled to the first flange part 122 of the frame 120 with the driving unit 130 interposed therebetween. That is, since the back cover 123 is coupled to the frame 120 , it may be understood as a stator. Through this, the body including the frame 120 , the driving unit 130 , and the like may be elastically supported in the axial direction and/or radial direction with respect to the casing 110 .

The back cover 123 may include a first opening 123c. The first opening 123c may be formed in a radially central region of the back plate part 123a. The first extension 163 of the first muffler unit 160 may reciprocate in the axial direction together with the piston 150 inside the first opening 123c.

The shape of the first opening 123c may correspond to the shape of the outer peripheral surface of the first extension 163 of the first muffler unit 160 . For example, when the first extension 163 has a pipe shape having a circular cross-sectional shape, the first opening 123c may also be formed in a circular shape.

An inner circumferential surface of the first opening 123c may be adjacent to an outer circumferential surface of the first extension 163 . Since the first extension part 163 can reciprocate in the axial direction inside the first opening part 123c , the radius of the first opening part 123c is slightly smaller than the radius of the outer surface of the first extension part 163 . can be large

When the refrigerant introduced through the suction pipe 114 flows into the first muffler through the second muffler unit 190 , all of the refrigerant in the second muffler unit 190 moves to the first muffler unit 160 . may be desirable. However, as described above, since the radius of the first opening 123c is slightly larger than the radius of the outer surface of the first extension 163, a portion of the refrigerant passes through the gap between the housing 110 and the receiving space ( 101) can flow.

The frame 120 may include a body portion 121 supporting the outer circumferential surface of the cylinder 140 , and a first flange portion 122 connected to one side of the body portion 121 and supporting the driving unit 130 . can The frame 120 may be elastically supported with respect to the casing 110 by the rear and front elastic members 116 and 117 together with the driving unit 130 and the cylinder 140 .

The body portion 121 may surround the outer circumferential surface of the cylinder 140 . The body portion 121 may be formed in a cylindrical shape. The first flange portion 122 may be formed to extend radially from the front end of the body portion 121 .

A cylinder 140 may be coupled to the inner circumferential surface of the body portion 121 . An inner stator 134 may be coupled to an outer circumferential surface of the body 121 . For example, the cylinder 140 may be fixed to the inner circumferential surface of the body portion 121 by press fitting, and the inner stator 134 may be fixed using a separate fixing ring (not shown).

The outer stator 131 may be coupled to the rear surface of the first flange part 122 , and the discharge cover assembly 180 may be coupled to the front surface thereof. For example, the outer stator 131 and the discharge cover assembly 180 may be fixed through a mechanical coupling means.

A bearing inlet groove 125a constituting a part of the gas bearing is formed on one side of the front surface of the first flange portion 122 , and a bearing communication hole 125b penetrates from the bearing inlet groove 125a to the inner circumferential surface of the body portion 121 . ) is formed, and a gas groove 125c communicating with the bearing communication hole 125b may be formed on the inner circumferential surface of the body portion 121 .

The bearing inlet groove 125a is formed by being depressed in the axial direction to a predetermined depth, and the bearing communication hole 125b is a hole having a smaller cross-sectional area than the bearing inlet groove 125a and is inclined toward the inner circumferential surface of the body portion 121. can In addition, the gas groove 125c may be formed in an annular shape having a predetermined depth and an axial length on the inner circumferential surface of the body portion 121 . Alternatively, the gas groove 125c may be formed on the outer circumferential surface of the cylinder 140 in contact with the inner circumferential surface of the body portion 121 or may be formed on both the inner circumferential surface of the body portion 121 and the outer circumferential surface of the cylinder 140 .

In addition, a gas inlet 142 corresponding to the gas groove 125c may be formed on the outer peripheral surface of the cylinder 140 .

Meanwhile, the frame 120 and the cylinder 140 may be formed of aluminum or an aluminum alloy material.

The cylinder 140 may be formed in a cylindrical shape in which both ends are open. The piston 150 may be inserted through the rear end of the cylinder 140 . The front end of the cylinder 140 may be closed via the discharge valve assembly 170 . A compression space 103 may be formed between the cylinder 140 , the front end of the piston 150 , and the discharge valve assembly 170 . Here, the front end of the piston 150 may be referred to as a head portion (151). The volume of the compression space 103 increases when the piston 150 moves backward, and decreases as the piston 150 moves forward. That is, the refrigerant introduced into the compression space 103 may be compressed while the piston 150 advances and discharged through the discharge valve assembly 170 .

The cylinder 140 may include a second flange portion 141 disposed at the front end. The second flange portion 141 may be bent to the outside of the cylinder 140 . The second flange portion 141 may extend in an outer circumferential direction of the cylinder 140 . The second flange portion 141 of the cylinder 140 may be coupled to the frame 120 . For example, the front side end of the frame 120 may be formed with a flange groove corresponding to the second flange portion 141 of the cylinder 140, the second flange portion 141 of the cylinder 140 is the It may be inserted into the flange groove and coupled through a coupling member.

On the other hand, a gas bearing means capable of lubricating the gas between the cylinder 140 and the piston 150 by supplying the discharge gas at an interval between the outer circumferential surface of the piston 150 and the outer circumferential surface of the cylinder 140 may be provided. The gas discharged between the cylinder 140 and the piston 150 may provide levitation force to the piston 150 to reduce friction between the piston 150 and the cylinder 140 .

For example, the cylinder 140 may include a gas inlet 142 . The gas inlet 142 may communicate with the gas groove 125c formed on the inner circumferential surface of the body 121 . The gas inlet 142 may radially penetrate the cylinder 140 . The gas inlet 142 may guide the compressed refrigerant flowing into the gas groove 125c between the inner circumferential surface of the cylinder 140 and the outer circumferential surface of the piston 150 . Alternatively, in consideration of the convenience of processing, the gas groove 125c may be formed on the outer peripheral surface of the cylinder 140 .

The inlet of the gas inlet 142 may be relatively wide, and the outlet may be formed as a fine hole to serve as a nozzle. A filter (not shown) for blocking the inflow of foreign substances may be additionally provided at the inlet of the gas inlet 142 . The filter may be a metal mesh filter, or may be formed by winding a member such as a fine thread.

A plurality of gas inlets 142 may be independently formed, or an inlet may be formed in an annular groove and a plurality of outlets may be formed at regular intervals along the annular groove. The gas inlet 142 may be formed only on the front side with respect to the middle of the cylinder 140 in the axial direction. Alternatively, the gas inlet 142 may also be formed on the rear side with respect to the middle of the cylinder 140 in the axial direction in consideration of the deflection of the piston 150 .

The piston 150 is inserted into the open end at the rear of the cylinder 140 , and is provided to seal the rear of the compression space 103 .

The piston 150 may include a head part 151 and a guide part 152 . The head part 151 may be formed in a disk shape. The head part 151 may be partially open. The head part 151 may partition the compression space 103 . The guide part 152 may extend rearward from the outer circumferential surface of the head part 151 . The guide part 152 may be formed in a cylindrical shape. The guide part 152 may be hollow inside and partially sealed by the head part 151 at the front. The rear of the guide part 152 may be opened to be connected to the first muffler unit 160 . The head unit 151 may be provided as a separate member coupled to the guide unit 152 . Alternatively, the head part 151 and the guide part 152 may be integrally formed.

The piston 150 may include a suction port 154 . The suction port 154 may pass through the head part 151 . The suction port 154 may communicate with the suction space 102 and the compression space 103 inside the piston 150 . For example, the refrigerant flowing into the suction space 102 inside the piston 150 from the receiving space 101 passes through the suction port 154 and the compression space 103 between the piston 150 and the cylinder 140 . ) can be inhaled.

The suction port 154 may extend in an axial direction of the piston 150 . The suction port 154 may be formed to be inclined in the axial direction of the piston 150 . For example, the suction port 154 may extend toward the rear of the piston 150 to be inclined in a direction away from the central axis.

The suction port 154 may have a circular cross-section. The suction port 154 may have a constant inner diameter. Alternatively, the suction port 154 may be formed as a long hole in which the opening extends in the radial direction of the head portion 151, or may be formed such that the inner diameter thereof increases toward the rear.

A plurality of suction ports 154 may be formed in any one or more directions of a radial direction and a circumferential direction of the head part 151 .

A suction valve 155 for selectively opening and closing the suction port 154 may be mounted on the head 151 of the piston 150 adjacent to the compression space 103 . The suction valve 155 may open or close the suction port 154 by operating by elastic deformation. That is, the suction valve 155 may be elastically deformed to open the suction port 154 by the pressure of the refrigerant flowing into the compression space 103 through the suction port 154 .

The piston 150 may be connected to the mover 135 . The mover 135 may reciprocate in the front-rear direction according to the movement of the piston 150 . An inner stator 134 and a cylinder 140 may be disposed between the mover 135 and the piston 150 . The mover 135 and the piston 150 may be connected to each other by a magnet frame 136 formed by bypassing the cylinder 140 and the inner stator 134 to the rear.

The linear compressor 100 may include muffler units 160 and 190 . The muffler units 160 and 190 are a first muffler unit 160 inserted into the rear of the piston 150 and coupled to the piston 150 , and a second muffler unit 190 coupled to the rear of the back cover 123 . may include The muffler units 160 and 190 may be formed of a plastic material in consideration of weight or insulation.

The muffler units 160 and 190 may include a first muffler unit 160 . The first muffler unit 160 includes an inner guide 161 disposed inside the piston 150 , a first suction muffler 162 disposed behind the inner guide 161 , and a first suction muffler 162 . It may include a first extension 163 disposed behind the second suction muffler 191 and communicating.

The first muffler unit 160 may include an inner guide 161 . One side of the inner guide 161 may be deeply inserted into the piston 150 , and the other side may communicate with the first first suction muffler 162 . The inner guide 161 may be formed in a pipe shape. Both ends of the inner guide 161 may have the same inner diameter. The inner guide 161 may be formed in a cylindrical shape. Alternatively, the inner diameter of the front end, which is the discharge side, may be formed to be larger than the inner diameter of the rear end, which is the opposite side.

The first muffler unit 160 may include a first suction muffler 162 . The first suction muffler 162 may be disposed behind the inner guide 161 . The first suction muffler 162 may be disposed inside the piston 150 and/or behind the piston 150 . The first extension part 163 may be disposed inside the first opening 123c formed in the back plate part 123a of the back cover 123 .

The first suction muffler 162 and the inner guide 161 may be provided in various shapes, and the pressure of the refrigerant passing through the muffler units 160 and 190 may be adjusted through them. The first suction muffler 162 and the inner guide 161 may be integrally formed.

The first muffler unit 160 may include a first extension part 163 . The first extension 163 may be disposed behind the first suction muffler 162 . The first extension 163 may be formed in a pipe shape. Both ends of the first extension 163 may have the same inner diameter. The first extension 163 may be formed in a cylindrical shape.

The first extension 163 may pass through the first opening 123c. That is, the first extension portion 163 may radially overlap the back plate portion 123a. In this case, the rear end of the first extension 163 passing through the first opening 123c may be disposed inside the second suction muffler 191 coupled to the rear of the back cover 123 . Accordingly, the first flow path 105 inside the first muffler unit 160 and the second flow path 106 inside the second muffler unit 190 may communicate with each other.

The first muffler unit 160 may form a first flow path 105 through which a refrigerant may flow. The first flow path 105 may extend from the front side through the inner guide 161 and the first suction muffler 162 in the axial direction to the first extension part 163 . The first flow path 105 may guide the refrigerant flowing into the first extension 163 from the second muffler unit 190 to the suction space 102 inside the piston 150 .

The first suction muffler 162 may form a first noise space 107 therein. The first noise space 107 may be disposed between the inner guide 161 and the first extension part 163 . The first noise space 107 may be formed to extend outwardly in the radial direction of the first flow path 105 from the middle of the first flow path 105 . Specifically, the radial length of the first noise space 107 may be greater than the inner diameter of the inner guide 161 and the inner diameter of the first extension 163 .

The flow passage cross-sectional area increases when the refrigerant moves from the first flow passage 105 of the first extension 163 to the first noise space 107 , and in the first noise space 107 , the first flow passage of the inner guide 161 again. It can be understood that it becomes smaller when moving to (105).

Unlike FIGS. 2 to 7 , a plurality of noise spaces divided by baffles may be formed inside the first suction muffler 162 . That is, the first suction muffler 162 may be formed by coupling two or more members to each other.

The muffler units 160 and 190 may include a second muffler unit 190 . The second muffler unit 190 may be coupled to the rear of the back cover 123 . The second muffler unit 190 may communicate with the first muffler unit 160 at the rear of the first muffler unit 160 . The second muffler unit 190 may include a second suction muffler 191 , a second extension part 192 , a second opening 193 , a connection auxiliary part 194 , and a nozzle part 195 . have.

The second muffler unit 190 may include a second suction muffler 191 . The second suction muffler 191 may be coupled to the rear of the back plate part 123a. The second suction muffler 191 may be in close contact with the rear surface of the back cover 123 . The rear of the second suction muffler 191 may be blocked. The second suction muffler 191 may be understood as a cap shape that covers the rear end of the first extension part 163 from the rear. Since the rear of the second suction muffler 191 is blocked, the refrigerant flow from the second suction muffler 191 to the rear in the axial direction may be blocked.

A second noise space 108 may be formed between the second suction muffler 191 and the rear surface of the back cover 123 . A rear end of the first extension 163 may be disposed in the second noise space 108 . At this time, since the first muffler unit 160 including the first extension part 163 is connected to the piston 150 and reciprocates in the axial direction, the rear end of the first extension part 163 is connected to the second noise space ( 108) can reciprocate in the axial direction.

That is, the rear end of the first muffler unit 160 may reciprocate in the axial direction inside the second muffler unit 190 . As such, when the first muffler unit 160 reciprocates independently from the second muffler unit 190 , the second muffler unit 190 communicates with the first muffler unit 160 , but may be fixed. can Accordingly, the refrigerant may be stably introduced into the second muffler unit 190 through the suction pipe 114 . In addition, it is possible to prevent a problem of a decrease in durability that may occur when the second muffler unit 190 collides with another part.

The second muffler unit 190 may include a second extension part 192 . The second extension 192 may be disposed radially outside the second suction muffler 191 and communicate with the second suction muffler 191 .

The second extension 192 may be in close contact with the back cover 123 . The second extension 192 may have a closed rear side. Accordingly, the second flow path 106 communicating with the second noise space 108 may be formed between the back cover 123 and the second extension part 192 .

In this case, the side surface of the back cover 123 of the second extension 192 is not blocked, and the second flow path 106 may be formed in which the second extension 192 is in close contact with the back cover 123 . . Accordingly, the manufacturing cost of the second muffler unit 190 can be reduced, and the space utilization inside the casing 110 can be improved.

It can be understood that the second flow path 106 is not limited to the inside of the second extension part 192 and extends to the inside of the second suction muffler 191 .

The radial length r2 of the inner surface of the second suction muffler 191 may be greater than the inner diameter r1 of the first extension part 163 . This is, from the viewpoint of the flow paths 105 and 106 through which the refrigerant flows, the axial flow path cross-sectional area of the second noise space 108 formed in the second suction muffler 191 is formed in the first extension portion 163 . It can be understood that the cross-sectional area of the passage 105 is larger than that of the first passage 105 .

The flow passage cross-sectional area S1 of the second suction muffler 191 may be greater than the flow passage cross-sectional area S2 of the second extension 192 . It is understood that, from the viewpoint of the flow paths 105 and 106 through which the refrigerant flows, the radial flow passage cross-sectional area S1 of the second noise space 108 is larger than the radial flow passage cross-sectional area S2 of the second flow passage 106 . can

Specifically, the second noise space 108 may be disposed between the first extension 163 and the second extension 192 . Therefore, it can be understood that the flow passage cross-sectional area increases when the refrigerant moves from the second flow passage 106 to the second noise space 108 and decreases when the refrigerant moves from the second noise space 108 back to the first flow passage 105 . have.

The linear compressor 100 according to the exemplary embodiment of the present specification may be formed as a single space without including a partition in the second noise space 108 and the second flow path 106 . However, unlike FIGS. 3 and 6 , a partition wall (not shown) may be installed between the second noise space 108 and the second flow path 106 to form a plurality of communicating spaces.

The second muffler unit 190 may include a second opening 193 . The refrigerant introduced through the suction pipe 114 may be introduced into the second muffler unit 190 through the second opening 193 . One end of the suction pipe 114 may face the second opening 193 .

On the contrary, since the accommodating space 101 inside the casing 110 is filled with refrigerant, the linear compressor 100 may operate normally even if the suction pipe 114 does not necessarily face the second opening 193 . However, as the linear compressor 100 is driven, the temperature of the refrigerant in the accommodating space may increase due to heat generated in the compression space 103 inside the cylinder. As the temperature of the refrigerant increases, the compression efficiency of the linear compressor 100 may decrease. Accordingly, as the suction pipe 114 is farther from the second opening 193 , the refrigerant having a higher temperature is introduced into the second opening 193 , thereby reducing the compression efficiency of the linear compressor 100 .

On the other hand, when the suction pipe 114 faces the second opening 193 , the refrigerant at room temperature flowing in from the outside of the casing 110 may directly flow into the second opening 193 , thereby lowering the efficiency due to the increase in the temperature of the refrigerant. problems can be avoided. Accordingly, it may be preferable that one end of the suction pipe 114 faces the second opening 193 .

The casing 110 of the linear compressor 100 according to an embodiment of the present specification includes a shell 111 having a substantially cylindrical shape with both ends open, and a first shell cover 112 coupled to both ends of the shell 111 and A second shell cover 113 may be included. Since the first shell cover 112 is welded to fit into the right opening of the shell 111 , a portion in which the edges of the shell 111 and the first shell cover 112 overlap in a radial direction may be formed. At this time, the suction pipe 114 may radially penetrate the shell 111 at a position where the shell 111 and the first shell cover 112 do not overlap in the radial direction. Accordingly, the suction pipe 114 may preferably pass through the shell 111 from the front.

As such, when one end of the suction pipe 114 is disposed in front of the first shell cover 112 , the second opening 193 opposite to one end of the suction pipe 114 also corresponds to the penetrating position of the suction pipe 114 . 2 It may be disposed in front of the suction muffler (191). That is, the second opening 193 may radially overlap the first muffler unit 160 .

In other words, the second extension portion 192 may extend radially outward from the second suction muffler 191 , and a portion of the extended portion may extend forward in the axial direction. In this case, the end extending in the axial direction may be disposed in front of the second suction muffler 191 .

Specifically, the second extension portion 192 includes a vertical portion 192a that communicates with the second suction muffler 191 and extends radially outward, and a horizontal portion 192b that communicates with the vertical portion 192a and extends forward. ) may be included.

The vertical portion 192a may be in close contact with the back plate portion 123a of the back cover 123 , and the horizontal portion 192b may be in close contact with the bridge portion 123b of the back cover 123 . Accordingly, the second extension portion 192 is in close contact with the back plate portion 123a and the bridge portion 123b of the back cover 123 , and the refrigerant flows between the second extension portion 192 and the back cover 123 . A second flow path 106 may be formed.

The second opening 193 may be disposed in the horizontal portion 192b. The second opening 193 may radially overlap the first muffler unit 160 . Specifically, the horizontal portion 192b may extend further forward than the penetrating position of the suction pipe 114 , and the second opening 193 is a position corresponding to the position of one end of the suction pipe 114 on the horizontal portion 192b. can be placed in

The axial length of the vertical portion 192a of the second extension 192 may be the same as the axial length of the second suction muffler 191 . That is, as shown in FIGS. 5 to 7 , the rear surface of the second extension part 192 and the rear surface of the second suction muffler 191 may be formed on the same plane. However, it is not limited thereto, and the axial length of the second extension part 192 and the axial length of the second suction muffler 191 are formed differently depending on the internal configuration of the linear compressor 100 or the required degree of compression noise attenuation. can be

The second muffler unit 190 may include a nozzle unit 195 . The nozzle unit 195 may be disposed between the second opening 193 and the suction pipe 114 . The nozzle unit 195 may effectively guide the refrigerant supplied from the suction pipe 114 to the second opening 193 .

A radially inner radius of the nozzle unit 195 may be smaller than a radially outer radius of the nozzle unit 195 . The radius of the nozzle part 195 may increase toward the outside in the radial direction. In other words, the shape of the nozzle unit 195 may be understood as being formed in a funnel shape.

A radially outer radius of the nozzle unit 195 may be greater than a radius of the suction pipe 114 . Through this, the refrigerant supplied from the suction pipe 114 may be effectively guided to the second opening 193 .

In addition, in order to effectively guide the refrigerant supplied from the suction pipe 114 to the second opening 193 , it may be preferable that the distance between the second opening 193 and one end of the suction pipe 114 is smaller. In this case, the nozzle part 195 may extend further outward in the radial direction than one end of the suction pipe 114 .

The nozzle unit 195 may be formed of an elastic material. For example, it may be formed of rubber. When the nozzle part 195 is made of an elastic material, it may be easy to press-fit the nozzle part 195 to the connection part. In addition, as described above, when the distance between one end of the suction pipe 114 and the second opening 193 is close, if the nozzle part 195 is formed of a rigid body rather than an elastic material, the piston 150 reciprocates. A collision between the nozzle unit 195 and the suction pipe 114 may occur due to vibration of the body due to movement. Such collision may cause noise, and may deteriorate durability of the linear compressor 100 . Therefore, the nozzle part 195 may be preferably formed of an elastic material.

Alternatively, the nozzle part 195 may be formed as a rigid body to be integrally formed with the second extension part 192 . In this case, in order to solve the above-described noise problem or durability problem, a certain distance may be provided between one end of the suction pipe 114 and the second opening 193 .

Also, unlike FIGS. 2 to 7 , the linear compressor 100 may not include the nozzle unit 195 .

The second muffler unit 190 may include a connection auxiliary unit 194 . The connection auxiliary part 194 may protrude to the outside of the second opening 193 . The connection auxiliary part 194 may be formed in a cylindrical shape. The cross-sectional shape of the inner circumferential surface of the connection auxiliary part 194 may correspond to the shape of the second opening 193 . The radially inner side of the nozzle part 195 may be coupled to the connection part by press fitting.

The second muffler unit 190 may include fixing parts 1961 and 1962. The fixing parts 1961 and 1962 may extend outwardly from the second suction muffler 191 . At least one fixing part 1961 and 1962 may be formed.

For example, it may be preferable that three fixing parts 1961 and 1962 are formed. When the number is less than three, the fixing force of the second muffler unit 190 to the back cover 123 may be reduced due to vibration of the main body due to the reciprocating motion of the piston 150 . When more than three are formed, the manufacturing cost may increase due to excessive use of the member, and the manufacturing process may become complicated. However, the present invention is not limited thereto, and the fixing parts 1961 and 1962 may be formed in various numbers according to durability required for the linear compressor 100 . When three fixing parts 1961 and 1962 are formed, each fixing part 1961 and 1962 may be formed at intervals of about 120 degrees from each other about an axis.

The fixing units 1961 and 1962 may include a first fixing unit 1961 and a second fixing unit 1962 . The first fixing part 1961 is a fixing part in which the second connection part 116c of the rear elastic member 116 is disposed, and the second fixing part 1962 is the second connection part 116c of the rear elastic member 116 is disposed. It may be a fixed part that does not work.

Since the rear elastic members 116 are formed in pairs, the first fixing part 1961 may also be formed in pairs. For example, when the rear elastic member 116 is connected to the upper portion of the inner surface of the casing 110 as shown in FIGS. 2 It may be formed in the upper right and upper left of the suction muffler 191, respectively. In this case, the second fixing part 1962 may be formed under the second suction muffler 191 .

The second connection part 116c of the rear elastic member 116 may be disposed between the back cover 123 and the first fixing part 1961 . In this case, a space for accommodating the second connection part 116c may be formed between the first fixing part 1961 and the back cover 123 . Specifically, the first fixing part 1961 may be formed in a cap shape that can cover the second connection part 116c in the front. In this case, the axial length of the first fixing part 1961 may be greater than the axial length of the second fixing part 1962 .

The first fixing part 1961 may include a first fixing hole 1961a, and the second fixing part 1962 may include a second fixing hole 1962a. The back cover 123 may include a third fixing hole 123d formed at a position corresponding to the position of the first fixing hole 1961a and the second fixing hole 1962a. The second connection part 116c may include a fourth fixing hole 116d formed at a position corresponding to the positions of the first fixing hole 1961a and the third fixing hole 123d.

The linear compressor 100 may include fixing members 1971 and 1972. The fixing members 1971 and 1972 may pass through the fixing parts 1961 and 1962 to be coupled to the back cover 123 . The other end of the rear elastic member 116 may be disposed between the fixing parts 1961 and 1962 and the back cover 123 .

Specifically, the fixing members 1971 and 1972 may include a first fixing member 1971 passing through the first fixing part 1961 and a second fixing member 1972 passing through the second fixing part 1962. can The first fixing member 1971 passes through the first fixing hole 1961a, the fourth fixing hole 116d, and the third fixing hole 123d to couple the second suction muffler 191 to the back cover 123 . can The second fixing member 1972 may pass through the second fixing hole 1962a and the third fixing hole 123d to couple the second suction muffler 191 to the back cover 123 . In this case, since the axial length of the first fixing part 1961 is greater than the axial length of the second fixing part 1962, the axial length of the first fixing member 1971 is equal to that of the second fixing member 1972. It may be greater than the axial length.

Unlike FIGS. 2 to 7 , the second suction muffler 191 may be coupled to the back cover 123 in various ways. For example, when an adhesive such as epoxy is used, the fixing members 1971 and 1972 may not be included.

Unlike FIGS. 2 to 7 , the rear elastic member 116 may be formed of various elastic members such as a leaf spring and a coil spring.

Hereinafter, the muffler units 160 and 190 will be described in terms of the flow paths 105 and 106 through which the refrigerant flows.

The muffler units 160 and 190 may form flow paths 105 and 106 of the refrigerant supplied to the piston 150 . The flow paths 105 and 106 may be understood as passages inside the muffler units 160 and 190 through which the refrigerant introduced into the muffler units 160 and 190 from the suction pipe 114 can flow. The flow paths 105 and 106 may guide the refrigerant introduced from the suction pipe 114 to the internal suction space of the piston 150 .

The flow paths 105 and 106 may include a first flow path 105 extending rearwardly in the piston 150 and a second flow path 106 extending radially outward of the first flow path 105 . The first flow path 105 may mean a flow path formed inside the first muffler unit 160 , and the second flow path 106 may mean a flow path formed inside the second muffler unit 190 .

The second flow path 106 may communicate at the rear of the first flow path 105 . Specifically, the rear end of the first flow path 105 may be disposed in the second noise space 108 . The second extension 192 may also communicate with the second noise space 108 . Accordingly, the first flow path 105 and the second flow path 106 may communicate with each other.

A portion of the second flow path 106 may extend forward from the radially outer side of the first flow path 105 . The refrigerant introduced from the suction pipe 114 may be introduced into the second flow path 106 through the second opening 193 . At this time, it is as described above that the suction pipe 114 and the second opening 193 preferably face each other. Accordingly, when the suction pipe 114 passes through the shell 111 from the front of the first shell cover 112 so as not to overlap the first shell cover 112 , the second opening 193 is formed by the first muffler unit 160 . A portion of the second flow path 106 may extend forward in response to the position of the second opening 193 and overlap in the radial direction.

The first muffler unit 160 may be connected to the piston 150 to reciprocate in the axial direction together with the piston 150 . Since the second muffler unit 190 is coupled to the back cover 123 , it may be fixed. That is, the first muffler unit 160 may be a mover, and the second muffler unit 190 may be a stator. Accordingly, the rear end of the first flow path 105 may be disposed in the second noise space 108 , and may reciprocate in the axial direction within the second noise space 108 .

The muffler units 160 and 190 may include a first noise space 107 and a second noise space 108 . The first noise space 107 may be formed inside the first suction muffler 162 , and the second noise space 108 may be formed inside the second suction muffler 191 .

The first muffler unit 160 may include a first noise space 107 . The first noise space 107 may be disposed between the inner guide 161 and the first extension part 163 . The first noise space 107 may be formed to extend outwardly in the radial direction of the first flow path 105 from the middle of the first flow path 105 . Accordingly, the flow passage cross-sectional area becomes large when the refrigerant moves from the first flow passage 105 of the first extension 163 to the first noise space 107 , and the first noise space 107 is again formed by the second internal guide 161 . It can be understood that it becomes smaller when moving to one flow path 105 .

The second muffler unit 190 may include a second noise space 108 . The second noise space 108 may be disposed between the first flow path 105 and the second flow path 106 . The radial length r2 of the second noise space 108 may be greater than the inner diameter r1 of the first flow path 105 . In other words, the cross-sectional area of the flow passage in the axial direction of the second noise space 108 may be greater than that of the first passage 105 .

Also, the flow passage cross-sectional area S1 of the second noise space 108 may be larger than the flow passage cross-sectional area S2 of the second flow passage 106 . Accordingly, it can be understood that the flow passage cross-sectional area increases when the refrigerant moves from the second flow passage 106 to the second noise space 108 and decreases when the refrigerant moves from the second noise space 108 back to the first flow passage 105 . .

When the linear compressor 100 is driven, the refrigerant is compressed in the compression space 103 inside the cylinder by the axial reciprocating motion of the piston 150 and discharged to the discharge space 104 . In this process, the pressure of the refrigerant changes and noise is generated. Compression noise generated in the compression space 103 and the piston 150 may move backward along the flow path.

Compression noise generated in front of the piston 150 passes through the inner guide 161 and is radiated to the first noise space 107 . At this time, since the passage cross-sectional area of the first noise space 107 is increased, the sound pressure of the compression noise may be lowered, and the compression noise may be attenuated. In addition, a portion of the compression noise may disappear while being reflected in the first noise space 107 .

Compressed noise passing through the first noise space 107 may be radiated to the second noise space 108 along the first extension part 163 . At this time, since the flow passage cross-sectional area of the second noise space 108 increases, the sound pressure of the compression noise may be lowered, and the compression noise may be attenuated. In addition, a portion of the compression noise may be dissipated while being reflected in the second noise space 108 .

The linear compressor 100 according to an embodiment of the present specification may include at least two noise spaces capable of attenuating compression noise as described above. That is, the linear compressor of the prior art includes one muffler unit, but the linear compressor 100 according to the exemplary embodiment of the present specification includes at least two muffler units 160 and 190, thereby increasing the compression noise attenuation effect. can do it

Meanwhile, the second suction muffler 191 may be in close contact with the rear surface of the back cover 123 . The rear of the second suction muffler 191 may be blocked. The second suction muffler 191 may be understood as a cap shape that covers the rear end of the first extension part 163 from the rear. Since the rear of the second suction muffler 191 is blocked, the refrigerant flow in the axial direction rearward in the second noise space 108 and the second flow path 106 may be blocked.

If the flow of the refrigerant is not blocked in the axial direction rearward of the flow path as in the conventional linear compressor, the compression noise may move backward along the flow path and then be radiated directly to the accommodation space inside the casing. As such, the noise radiated to the accommodation space inside the casing may resonate with the refrigerant filled in the accommodation space. That is, resonance noise may occur.

The above-described resonance noise may be generated in the axial direction and the radial direction, respectively. In general, in the case of the linear compressor 100, the length in the axial direction may be longer than the length in the radial direction. Accordingly, the axial resonance noise may have a lower frequency (300 to 400 hz) than the radial resonance noise.

Unlike the linear compressor 100 according to the exemplary embodiment of the present specification, if the refrigerant flow in the axial direction from the rear of the piston 150 is not blocked, the compression noise may be directly radiated in the axial direction along the flow path. In this case, since the noise radiated in the axial direction resonates with the refrigerant in the accommodation space 101 in the axial direction, the low-frequency resonance noise may increase.

However, in the linear compressor 100 according to the embodiment of the present specification, since the refrigerant flow in the axial direction is blocked by the second muffler unit 190 as described above, the compression noise is generated in the flow passages 105 and 106 . It is possible to prevent direct radiation in the axial direction along the Therefore, through the linear compressor 100 according to the embodiment of the present specification, it is possible to reduce the low-frequency resonance noise generated by resonating with the refrigerant in the accommodating space 101 in the axial direction.

The linear compressor 100 may include a discharge valve assembly 170 . The discharge valve assembly 170 may include a discharge valve 171 and a valve spring 172 provided on the front side of the discharge valve 171 to elastically support the discharge valve 171 . The discharge valve assembly 170 may selectively discharge the refrigerant compressed in the compression space 103 . Here, the compression space 103 means a space formed between the intake valve 155 and the discharge valve 171 .

The discharge valve 171 may be disposed to be supported on the front surface of the cylinder 140 . The discharge valve 171 may selectively open and close the front opening of the cylinder 140 . The discharge valve 171 may open or close the compression space 103 by operating by elastic deformation. The discharge valve 171 may be elastically deformed to open the compression space 103 by the pressure of the refrigerant flowing into the discharge space 104 through the compression space 103 . For example, in a state in which the discharge valve 171 is supported on the front surface of the cylinder 140 , the compression space 103 maintains a closed state, and the discharge valve 171 is spaced apart from the front surface of the cylinder 140 . The compressed refrigerant of the compressed space 103 may be discharged to the open space in the .

The valve spring 172 may be provided between the discharge valve 171 and the discharge cover assembly 180 to provide an elastic force in the axial direction. The valve spring 172 may be provided as a compression coil spring, or may be provided as a leaf spring in consideration of occupied space or reliability.

When the pressure in the compression space 103 is equal to or greater than the discharge pressure, the valve spring 172 deforms forward to open the discharge valve 171 , and the refrigerant is discharged from the compression space 103 to the discharge cover assembly 180 . It may be discharged to the first discharge space 104a. When the discharge of the refrigerant is completed, the valve spring 172 may provide a restoring force to the discharge valve 171 to close the discharge valve 171 .

A process in which the refrigerant flows into the compression space 103 through the suction valve 155 and the refrigerant in the compression space 103 is discharged to the discharge space 104 through the discharge valve 171 will be described as follows.

In the course of the piston 150 reciprocating and linear motion inside the cylinder 140 , when the pressure in the compression space 103 becomes less than a predetermined suction pressure, the suction valve 155 is opened and the refrigerant flows into the compression space 103 . is inhaled On the other hand, when the pressure in the compression space 103 exceeds the predetermined suction pressure, the refrigerant in the compression space 103 is compressed in the closed state of the suction valve 155 .

On the other hand, when the pressure in the compression space 103 is equal to or greater than the predetermined discharge pressure, the valve spring 172 deforms forward and opens the discharge valve 171 connected thereto, and the refrigerant is discharged from the compression space 103 into the discharge cover assembly ( It is discharged to the discharge space 104 of 180). When the discharge of the refrigerant is completed, the valve spring 172 provides a restoring force to the discharge valve 171 , and the discharge valve 171 is closed to seal the front of the compression space 103 .

The discharge cover assembly 180 is installed in front of the compression space 103 to form a discharge space 104 for accommodating the refrigerant discharged from the compression space 103 , and is coupled to the front of the frame 120 to provide the refrigerant. It is possible to reduce noise generated in the process of being discharged from the compressed space 103 . The discharge cover assembly 180 may be coupled to the front of the first flange portion 122 of the frame 120 while accommodating the discharge valve assembly 170 . For example, the discharge cover assembly 180 may be coupled to the first flange part 122 through a mechanical coupling member.

And between the discharge cover assembly 180 and the frame 120, a gasket 165 for insulation and an O-ring 166 (O-ring) for suppressing leakage of the refrigerant in the discharge space 104 may be provided. .

The discharge cover assembly 180 may be formed of a thermally conductive material. Accordingly, when a high-temperature refrigerant flows into the discharge cover assembly 180 , the heat of the refrigerant is transferred to the casing 110 through the discharge cover assembly 180 to be radiated to the outside of the linear compressor.

The discharge cover assembly 180 may include a single discharge cover, or a plurality of discharge covers may be arranged to communicate sequentially. When the discharge cover assembly 180 is provided with a plurality of discharge covers, the discharge space 104 may include a plurality of space portions partitioned by each discharge cover. The plurality of space portions may be disposed in the front-rear direction and may communicate with each other.

For example, when there are three discharge covers, the discharge space 104 is a first discharge space 104a formed between the frame 120 and the first discharge cover 181 coupled to the front side of the frame 120 . and a second discharging space 104b formed between the second discharging cover 182 and the first discharging cover 181 communicating with the first discharging space 104a and coupled to the front side of the first discharging cover 181 . ), and a third discharge space ( 104c).

In addition, the first discharge space 104a selectively communicates with the compression space 103 by the discharge valve 171 , the second discharge space 104b communicates with the first discharge space 104a , and the third discharge The space 104c may communicate with the second discharge space 104b. Accordingly, the refrigerant discharged from the compression space 103 passes through the first discharge space 104a, the second discharge space 104b, and the third discharge space 104c in sequence, the discharge noise is attenuated, and the third discharge It may be discharged to the outside of the casing 110 through the roof pipe 115a and the discharge pipe 115 communicating with the cover 183 .

The driving unit 130 includes an outer stator 131 disposed between the shell 111 and the frame 120 to surround the body portion 121 of the frame 120 , and between the outer stator 131 and the cylinder 140 . It may include an inner stator 134 disposed to surround the cylinder 140 , and a mover 135 disposed between the outer stator 131 and the inner stator 134 .

The outer stator 131 may be coupled to the rear of the first flange portion 122 of the frame 120 , and the inner stator 134 may be coupled to the outer peripheral surface of the body portion 121 of the frame 120 . In addition, the inner stator 134 may be disposed to be spaced apart from the inside of the outer stator 131 , and the mover 135 may be disposed in a space between the outer stator 131 and the inner stator 134 .

A winding coil may be mounted on the outer stator 131 , and the mover 135 may include a permanent magnet. The permanent magnet may be configured as a single magnet having one pole, or by combining a plurality of magnets having three poles.

The outer stator 131 may include a coil winding body 132 surrounding the axial direction in a circumferential direction and a stator core 133 stacked while surrounding the coil winding body 132 . The coil winding body 132 may include a hollow cylindrical bobbin 132a and a coil 132b wound in a circumferential direction of the bobbin 132a. The cross-section of the coil 132b may be formed in a circular or polygonal shape, for example, may have a hexagonal shape. In the stator core 133 , a plurality of lamination sheets may be radially stacked, and a plurality of lamination blocks may be stacked along a circumferential direction.

The front side of the outer stator 131 may be supported by the first flange part 122 of the frame 120 , and the rear side may be supported by the stator cover 137 . For example, the stator cover 137 may be provided in the shape of a hollow disk, the outer stator 131 may be supported on the front surface, and the resonance spring 118 may be supported on the rear surface.

The inner stator 134 may be configured by stacking a plurality of laminations on the outer circumferential surface of the body portion 121 of the frame 120 in the circumferential direction.

One side of the mover 135 may be coupled to and supported by the magnet frame 136 . The magnet frame 136 has a substantially cylindrical shape and may be disposed to be inserted into a space between the outer stator 131 and the inner stator 134 . And the magnet frame 136 is coupled to the rear side of the piston 150 may be provided to move together with the piston (150).

For example, the rear end of the magnet frame 136 is bent and extended in the radial direction to form a first coupling portion 136a, the first coupling portion 136a is a third formed in the rear of the piston (150) It may be coupled to the flange portion 153 . The first coupling portion 136a of the magnet frame 136 and the third flange portion 153 of the piston 150 may be coupled through a mechanical coupling member.

Furthermore, through this, the piston 150, the first muffler unit 160, and the mover 135 may reciprocate in the axial direction together in a state in which they are integrally coupled.

When a current is applied to the driving unit 130 , magnetic flux is formed in the winding coil, and the magnetic flux formed in the winding coil of the outer stator 131 and the magnetic flux formed by the permanent magnet of the mover 135 are mutually Electromagnetic force is generated by the action, so that the mover 135 can move. Also, the piston 150 connected to the magnet frame 136 may reciprocate in the axial direction integrally with the mover 135 at the same time as the reciprocating movement of the mover 135 in the axial direction.

Meanwhile, the driving unit 130 and the compression units 140 and 150 may be supported in the axial direction by the elastic members 116 and 117 and the resonance spring 118 .

The resonance spring 118 amplifies the vibration implemented by the reciprocating motion of the mover 135 and the piston 150, thereby achieving effective compression of the refrigerant. Specifically, the resonance spring 118 may be adjusted to a frequency corresponding to the natural frequency of the piston 150 to allow the piston 150 to perform a resonant motion. In addition, the resonance spring 118 may induce a stable movement of the piston 150 to reduce vibration and noise generation.

The resonant spring 118 may be an axially extending coil spring. Both ends of the resonance spring 118 may be connected to the vibrating body and the fixed body, respectively. For example, one end of the resonance spring 118 may be connected to the magnet frame 136 , and the other end may be connected to the back cover 123 . Therefore, the resonance spring 118 may be elastically deformed between the vibrating body vibrating at one end and the fixed body fixed at the other end.

The natural frequency of the resonant spring 118 is designed to match the resonant frequency of the mover 135 and the piston 150 during the operation of the linear compressor 100 , thereby amplifying the reciprocating motion of the piston 150 . However, since the back cover 123 provided as a fixed body is elastically supported by the rear elastic member 116 on the casing 110 , it may not be strictly fixed.

The resonance spring 118 may include a first resonance spring 118a supported on the rear side with respect to the spring supporter 119 and a second resonance spring 118b supported on the front side.

The spring supporter 119 includes a body portion 119a surrounding the first suction muffler 162 , a second coupling portion 119b bent in the inner radial direction from the front of the body portion 119a, and the body portion 119a ) may include a support portion 119c that is bent in the outer radial direction from the rear.

The front surface of the second coupling part 119b of the spring supporter 119 may be supported by the first coupling part 136a of the magnet frame 136 . The inner diameter of the second coupling portion 119b of the spring supporter 119 may surround the outer diameter of the first suction muffler 162 . For example, the second coupling portion 119b of the spring supporter 119, the first coupling portion 136a of the magnet frame 136, and the third flange portion 153 of the piston 150 are sequentially disposed It may then be integrally coupled through a mechanical member.

The first resonance spring 118a may be disposed between the front surface of the back cover 123 and the rear surface of the spring supporter 119 . The second resonance spring 118b may be disposed between the rear surface of the stator cover 137 and the front surface of the spring supporter 119 .

A plurality of first and second resonance springs 118a and 118b may be disposed in a circumferential direction of the central axis. The first resonance spring 118a and the second resonance spring 118b may be disposed side by side in the axial direction, or may be disposed alternately with each other. The first and second resonance springs 118a and 118b may be disposed at regular intervals in the radial direction of the central axis. For example, the first and second resonant springs 118a and 118b may be provided three each, and may be disposed at intervals of 120 degrees in the radial direction of the central axis.

The linear compressor 100 may include a plurality of sealing members capable of increasing the coupling force between the frame 120 and parts around the frame 120 .

For example, the plurality of sealing members are interposed in a portion where the frame 120 and the discharge cover assembly 180 are coupled, and a first sealing member inserted into an installation groove provided at the front end of the frame 120 and the frame ( It may include a second sealing member provided at a portion where the 120 and the cylinder 140 are coupled and inserted into the installation groove provided on the outer surface of the cylinder 140 . The second sealing member prevents the refrigerant in the gas groove 125c formed between the inner circumferential surface of the frame 120 and the outer circumferential surface of the cylinder 140 from leaking to the outside, and increases the coupling force between the frame 120 and the cylinder 140 . can increase In addition, the plurality of sealing members may further include a third sealing member provided at a portion where the frame 120 and the inner stator 134 are coupled and inserted into an installation groove provided on the outer surface of the frame 120 . Here, the first to third sealing members may have a ring shape.

The operation of the linear compressor 100 described above is as follows.

First, when a current is applied to the driving unit 130 , a magnetic flux may be formed in the outer stator 131 by the current flowing through the coil 132b. The magnetic flux formed in the outer stator 131 generates an electromagnetic force, and the mover 135 having a permanent magnet may reciprocate linearly by the generated electromagnetic force. This electromagnetic force is generated in the direction (forward direction) toward the top dead center (TDC) of the piston 150 during the compression stroke, and the piston 150 moves to the bottom dead center (BDC) during the suction stroke. ) may occur alternately in the direction toward (rear direction). That is, the driving unit 130 may generate thrust, which is a force that pushes the mover 135 and the piston 150 in the moving direction.

The piston 150 linearly reciprocating within the cylinder 140 may repeatedly increase or decrease the volume of the compression space 103 .

When the piston 150 moves in a direction (rear direction) to increase the volume of the compression space 103 , the pressure of the compression space 103 may decrease. Accordingly, the suction valve 155 mounted on the front of the piston 150 is opened, and the refrigerant staying in the suction space 102 may be sucked into the compression space 103 along the suction port 154 . This suction stroke may proceed until the piston 150 is positioned at the bottom dead center by maximally increasing the volume of the compression space 103 .

The piston 150 that has reached the bottom dead center may perform a compression stroke while moving in a direction (forward direction) in which the movement direction is changed to reduce the volume of the compression space 103 . During the compression stroke, the suctioned refrigerant may be compressed while the pressure of the compression space 103 is increased. When the pressure of the compression space 103 reaches the set pressure, the discharge valve 171 is pushed out by the pressure of the compression space 103 and is opened from the cylinder 140, and the refrigerant is discharged from the discharge space 104 through the spaced apart space. ) can be discharged. This compression stroke may be continued while the piston 150 moves to the top dead center where the volume of the compression space 103 is minimized.

As the suction stroke and the compression stroke of the piston 150 are repeated, the refrigerant introduced into the linear compressor 100 through the suction pipe 114 passes through the muffler units 160 and 190 to the suction space 102 inside the piston 150 . ), and the refrigerant in the suction space 102 may be introduced into the compression space 103 inside the cylinder 140 during the suction stroke of the piston 150 . After the refrigerant in the compression space 103 is compressed during the compression stroke of the piston 150 and discharged to the discharge space 104 , it is discharged to the outside of the linear compressor 100 through the loop pipe 115a and the discharge pipe 115 . An outgoing stream may be formed.

8 is a cross-sectional view of a partial configuration of the linear compressor 100 according to another embodiment of the present specification. 9 is a perspective view of the second muffler unit 290 of the linear compressor 100 according to another embodiment of the present specification.

The detailed configuration of the linear compressor 100 according to another embodiment of the present specification according to FIGS. 8 to 9, which is not described below, is a detail of the linear compressor 100 according to an embodiment of the present specification according to FIGS. 4 to 7 . It can be understood as the same as the configuration.

8 and 9 , the linear compressor 100 may include a second muffler unit 290 . The second muffler unit 290 may be coupled to the rear of the back cover 123 . The second muffler unit 190 may communicate with the first muffler unit 160 at the rear of the first muffler unit 160 .

The second muffler unit 290 may include a second suction muffler 291 , a second extension part 292 , and a connection auxiliary part 294 .

The second muffler unit 290 may include a second suction muffler 291 . The second suction muffler 291 may be coupled to the rear of the back plate part 123a. The second suction muffler 191 may be in close contact with the rear surface of the back cover 123 . The rear of the second suction muffler 291 may be blocked. The second suction muffler 291 may be understood as a cap shape that covers the rear end of the first extension part 163 from the rear. Since the rear of the second suction muffler 291 is blocked, the refrigerant flow from the second suction muffler 291 to the rear in the axial direction may be blocked.

A second noise space 208 may be formed between the second suction muffler 291 and the rear surface of the back cover 123 . A rear end of the first extension 163 may be disposed in the second noise space 208 . At this time, since the first muffler unit 160 including the first extension part 163 is connected to the piston 150 and reciprocates in the axial direction, the rear end of the first extension part 163 is connected to the second noise space ( 208) can reciprocate in the axial direction.

The second muffler unit 190 may include a second extension 292 . The second extension 292 may be disposed radially outside the second suction muffler 291 and communicate with the second suction muffler 291 .

The second extension 292 may be formed in a pipe shape. A cross-sectional shape of the second extension 292 may be formed in various ways. For example, as shown in FIG. 9 , the cross-section of the second extension 292 may have a substantially rectangular shape. However, the present invention is not limited thereto, and the cross-sectional shape of the second extension portion 292 may be variously formed, such as a circular shape, a semi-circular shape, or a polygonal shape.

The second flow path 206 may be formed inside the second extension part 292 . The second flow path 206 may be formed independently of the back cover 123 . That is, unlike the linear compressor 100 according to the exemplary embodiment of the present specification, the back cover 223 side of the second extension portion 292 may be blocked. Accordingly, the second flow path 106 may be formed inside the second extension part 292 even if it is not in close contact with the back cover 123 . It can be understood that the second flow path 206 is not limited to the inside of the second extension 292 , but extends to the inside of the second suction muffler 291 .

The second extension 292 may be integrally formed with the second suction muffler 291 . However, the present invention is not limited thereto, and the second extension portion 292 may be separately manufactured and coupled to the second suction muffler 291 . In this case, the second extension part 292 and the second suction muffler 291 may be formed of the same material or different materials.

When the second extension part 292 is separately formed and assembled from the second suction muffler 291 , the shape of each of the second suction muffler 291 and the second extension part 292 may be simplified. Accordingly, the manufacturing process can be simplified, and the manufacturing cost can be reduced.

Unlike FIGS. 8 and 9 , the second extension part 292 may be disposed behind the second suction muffler 291 and may communicate with the rear surface of the second suction muffler 291 . In this case, in order to achieve the object of the present specification, the second extension 292 may be bent radially outward.

As described above, when the second extension portion 292 is formed of a pipe, the second extension portion 292 may be formed in a more free form. Accordingly, it may be easy to match the position of the suction pipe 214 penetrating into the casing 210 with the position of the second opening 293 formed in the second extension part 292 . In addition, since it may be formed in various shapes corresponding to the arrangement of the internal components of the casing 110 , the space efficiency inside the casing 110 may be increased.

In addition, when the temperature of the refrigerant introduced from the suction pipe 114 increases, the efficiency of the linear compressor 100 may decrease. 8 and 9 , when the second extension part 292 is not in close contact with the back cover 123 , heat generated while the refrigerant is compressed in the compression space 103 is directly transferred to the second through the back cover 123 . It can be prevented from being transmitted to the extension 292 . Therefore, in the linear compressor 100 according to another embodiment of the present specification, since it is possible to prevent the temperature rise of the refrigerant passing through the second flow path 206 formed in the second extension part 292 , the linear compressor It is possible to increase the compression efficiency of (100).

10 is a side view of the linear compressor 100 according to an embodiment of the present specification.

Referring to FIG. 10 , in the machine room of the refrigerator, the linear compressor 100 and the cooling fan PAN may be disposed in this order from the front. At this time, the cooling fan PAN may serve to cool the heat of the casing 110 generated while the linear compressor 100 is driven.

Referring to FIG. 10 , in the linear compressor 100 according to an exemplary embodiment of the present specification, the suction pipe 114 may be coupled to the side surface of the casing 110 , that is, the shell 111 in a radial direction.

When viewed from the side of the linear compressor 100 , the outer portion of the casing 110 of the suction pipe 114 may be coupled to the casing 110 at a predetermined angle a. An outer portion of the casing 110 of the suction pipe 114 may be connected to a refrigerant pipe introduced into the machine room of the refrigerator. In this case, the outer portion of the casing 110 of the suction pipe 114 may be disposed to form an appropriate angle (a) according to the structure of the refrigerator machine room or the incoming position of the refrigerant pipe. When viewed from the side of the casing 110, the angle (a) may have a positive (+) value or a negative (-) value based on the vertical line (L).

In the linear compressor 100 according to the present specification, it is possible to reduce the suction pipe installation space G1 between the cooling fan PAN and the linear compressor 100 . Furthermore, only a minimum space for cooling is formed between the linear compressor 100 and the cooling fan PAN, and the suction pipe installation space G1 may not be required.

As such, it is possible to increase the space efficiency of the refrigerator machine room through the linear compressor 100 according to the embodiment of the present specification. In addition, by reducing the distance between the linear compressor 100 and the cooling fan PAN, it is possible to increase the cooling efficiency by the cooling fan PAN.

The present invention is not limited thereto, and the outer portion of the casing 110 of the suction pipe 114 may be formed in various shapes depending on the structure of the refrigerator machine room or the location of the refrigerant pipe entering the machine room.

Any or other embodiments of the present specification described above are not mutually exclusive or distinct. Any of the above-described embodiments or other embodiments of the present specification may be combined or combined in each configuration or function.

For example, it means that configuration A described in a specific embodiment and/or drawings may be combined with configuration B described in other embodiments and/or drawings. That is, even if the combination between the components is not directly described, it means that the combination is possible except for the case where it is described that the combination is impossible.

The above detailed description should not be construed as restrictive in all respects and should be considered as illustrative. The scope of this specification should be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of this specification are included in the scope of this specification.

100: linear compressor 101: accommodation space
102: suction space 103: compression space
104: discharge space 105: first flow path
106: second flow path 107: first noise space
108: second noise space 110: casing
111: shell 112: first shell cover
113: second shell cover 114: suction pipe
115: discharge pipe 115a: loop pipe
116: rear elastic member 116a: elastic part
116b: first connection portion 116c: second connection portion
116d: fourth fixing hole 117: front elastic member
117a: support bracket 117b: first support guide
117c: support cover 117d: second support guide
117e: third support guide 118: resonance spring
118a: first resonant spring 118b: second resonant spring
119: spring supporter 119a: body portion
119b: second coupling portion 119c: support portion
119d: third coupling part 119e: fourth coupling part
120: frame 121: body part
122: first flange portion 123: back cover
123a: back plate part 123b: bridge part
123c: first opening 123d: third coupling hole
130: drive unit 131: outer stator
132: coil winding body, 132a: bobbin
132b: coil 133: stator core
134: inner stator 135: mover
136: magnet frame 136a: first coupling portion
137: stator cover 140: cylinder
141: second flange portion 142: gas inlet
150: piston 151: head portion
152: guide portion 153: third flange portion
154: suction port 155: suction valve
160: first muffler unit 161: inner guide
162: first suction muffler 163: first extension
170: discharge valve assembly 171: discharge valve
172: valve spring 180: discharge cover assembly
181: first discharge cover 182: second discharge cover
183: third discharge cover 190: second muffler unit
191: second suction muffler 192: second extension
192a: vertical portion 192b: horizontal portion
193: second opening 194: connection auxiliary part
195: nozzle unit 1961: first fixing unit
1961a: first fixing hole 1962: second fixing part
1962a: second fixing hole 1971: first fixing member
1972: second fixing member

Claims (20)

cylinder;
a piston reciprocating in the axial direction within the cylinder;
a first muffler unit coupled to the piston;
a back cover including a first opening formed in a radially central region and disposed behind the piston; and
a second muffler unit coupled to the rear of the back cover;
The first muffler unit may include an inner guide disposed inside the piston, a first suction muffler disposed behind the inner guide, and a first suction muffler disposed behind the first suction muffler and passing through the first opening. including an extension;
The second muffler unit may include a second suction muffler communicating with the first extension part, and a second extension part disposed radially outside the second suction muffler and communicating with the second suction muffler. According to claim 1,
a second noise space is formed between the second suction muffler and a rear surface of the back cover;
The rear end of the first extension part reciprocates in the axial direction in the second noise space. 3. The method of claim 2,
The second extension is in close contact with the back cover,
A second flow path communicating with the second noise space is formed between the back cover and the second extension part. According to claim 1,
the second muffler unit includes a second opening formed in the second extension;
The second opening portion overlaps the first muffler unit in a radial direction. According to claim 1,
The second extension portion includes a vertical portion communicating with the second suction muffler and extending radially outward, and a horizontal portion communicating with the vertical portion and extending forward. 5. The method of claim 4,
The second opening is disposed in front of the second suction muffler. According to claim 1,
An inner circumferential surface of the first opening is adjacent to an outer circumferential surface of the first extension portion. According to claim 1,
A radial length of an inner surface of the second suction muffler is greater than an inner diameter of the first extension. According to claim 1,
A flow path cross-sectional area of the second suction muffler is larger than a flow path cross-sectional area of the second extension part. According to claim 1,
a casing accommodating the cylinder;
a rear elastic member having one end connected to the casing and the other end connected to the back cover; and
and a fixing member for fixing the second muffler unit to the back cover;
the second muffler unit includes a fixing part extending outwardly from the second suction muffler;
The fixing member passes through the fixing part and is coupled to the back cover,
The other end of the rear elastic member is disposed between the fixing part and the back cover. According to claim 1,
a casing accommodating the cylinder; and
and a suction pipe passing through the casing in a radial direction and supplying a refrigerant to the second muffler unit. 12. The method of claim 11,
the second muffler unit includes a second opening formed in the second extension;
One end of the suction pipe is opposed to the second opening. 13. The method of claim 12,
and a nozzle part disposed between the second opening and the suction pipe,
A linear compressor in which a radially inner radius of the nozzle unit is smaller than a radially outer radius. 14. The method of claim 13,
the second muffler unit includes a connection auxiliary part protruding outward from the second opening;
One side of the nozzle part is press-fitted to the connection auxiliary part. 14. The method of claim 13,
The radially outer inner diameter of the nozzle portion is larger than the outer diameter of the suction pipe linear compressor. cylinder;
a piston reciprocating in the axial direction within the cylinder; and
and a muffler unit forming a flow path of the refrigerant supplied to the piston;
The flow path includes a first flow path extending rearwardly within the piston, and a second flow path extending radially outward from the first flow path,
At least a portion of the second flow path is disposed outside the piston and the first flow path in the radial direction,
A portion of the second flow path extends forward from the radially outer side of the first flow path. 17. The method of claim 16,
and a second noise space disposed between the first flow path and the second flow path,
a radial length of the second noise space is greater than a radial length of the first flow path;
A flow passage cross-sectional area of the second noise space is larger than a flow passage cross-sectional area of the second flow passage. delete 17. The method of claim 16,
the muffler unit includes a first muffler unit forming the first flow path and a second muffler unit forming the second flow path;
the first muffler unit is coupled to the piston;
A rear end of the first muffler unit reciprocates in an axial direction inside the second muffler unit. 17. The method of claim 16,
a casing accommodating the cylinder; and
and a suction pipe passing through a side surface of the casing and supplying a refrigerant to the second flow path.

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