KR20190036310A - Linear compressor - Google Patents

Abstract

The present invention relates to a linear compressor. According to the present invention, the linear compressor may comprise: a casing with a sealed internal space; a linear motor placed in the internal space of the casing to have a mover make a reciprocating motion towards a stator; a cylinder placed in an internal side of the linear motor to form a compression space; a piston placed in the cylinder to make a reciprocating motion together with the mover and to vary the volume of the compression space; one or more discharge covers which have a discharge space to accommodate a refrigerant discharged from the compression space; a frame into which the cylinder is inserted and fixated and having a front surface combined with the discharge covers; and an insulation cover having one or more insulation space units between the discharge covers and the frame to be separated from the discharge space of the discharge covers and to communicate with the internal space of the casing. As such, the linear compressor is able to block heat from being transferred from the discharge covers to the frame, thereby increasing the efficiency of the compressor.

Description

[0001] LINEAR COMPRESSOR [0002]

The present invention relates to a linear compressor for lubricating between a cylinder and a piston with a refrigerant.

Generally, a compressor is a device that receives power from a power generating device such as a motor or a turbine and compresses a working fluid such as air or refrigerant. Compressors are widely applied to industrial and household appliances, especially vapor compression refrigeration cycles (hereinafter referred to as " refrigeration cycles ").

Such a compressor can be classified into a reciprocating compressor, a rotary compressor, and a scroll compressor according to a method of compressing a refrigerant. The reciprocating compressor is a system in which a compression space is formed between a piston and a cylinder, and a piston reciprocates linearly to compress the fluid. The rotary compressor compresses the fluid by a roller eccentrically rotated in the cylinder. The scroll compressor is a spiral type And the fluid is compressed.

BACKGROUND ART [0002] Reciprocating compressors are known as a crank system that compresses a refrigerant by converting a rotational force of a rotary motor into a linear motion, and a vibration system that compresses a refrigerant by using a linear motor that performs linear reciprocating motion. The oscillating type reciprocating compressor is referred to as a linear compressor. The linear compressor has no mechanical loss in converting the rotational motion into a linear reciprocating motion, thereby improving the efficiency and simplifying the structure.

On the other hand, the linear compressor can be divided into an oil-lubricated linear compressor and a gas-type linear compressor according to the lubrication system. The oil-lubricated linear compressor is configured to store a predetermined amount of oil in the casing and lubricate the cylinder and the piston using the oil, as disclosed in Patent Document 1 (Korean Patent Laid-Open Publication No. KR10-2015-0040027). On the other hand, as disclosed in Patent Document 2 (Korean Patent Laid-Open Publication No. KR10-2016-0024217), the gas-lubricated linear compressor has a structure in which a part of the refrigerant discharged from the compression space without guiding oil into the casing is guided between the cylinder and the piston And is configured to lubricate between the cylinder and the piston by the gas force of the refrigerant.

The oil-lubricated linear compressor can prevent the cylinder and the piston from being overheated by the heat of the motor, the heat of compression, etc., as the oil of relatively low temperature is supplied between the cylinder and the piston. As a result, the oil-lubricated linear compressor can prevent the suction loss from being generated by suppressing the rise of the refrigerant heated by the suction passage of the refrigerant passing through the suction passage of the piston into the compression chamber of the cylinder.

However, in the oil-lubricated linear compressor, when the oil discharged to the refrigeration cycle apparatus together with the refrigerant is not smoothly recovered to the compressor, oil shortage may occur in the casing of the compressor. Which may cause the reliability to deteriorate.

On the other hand, the gas-lubricated linear compressor is advantageous in that it can be downsized as compared with the oil-lubricated linear compressor and lubricates between the cylinder and the piston with the refrigerant, so that the reliability of the compressor is not lowered due to oil shortage.

However, in the conventional gas lubricating type linear compressor as described above, since the cylinder and the piston are heated by the refrigerant by using the high-temperature refrigerant gas, the refrigerant is sucked into the compression space, The refrigerant compressed in the space is overheated to cause a suction loss or a compression loss.

Further, in the conventional gas lubricated linear compressor, the refrigerant discharged from the compression space of the cylinder to the discharge space of the discharge cover heats the discharge cover, and the heated discharge cover transfers heat to the frame in contact with the discharge cover, There is a problem that the suction loss and the compression loss described above are increased.

Further, in the conventional gas lubricated linear compressor, the refrigerant discharged from the compression space of the cylinder to the discharge space of the discharge cover directly contacts the frame and the cylinder, and the frame is heated together with the cylinder, so that the suction loss and the compression loss, There was also a problem.

Korean Unexamined Patent Application Publication No. 10-2015-0040027 A (published on Apr. 14, 2014) Korean Patent Laid-Open Publication No. KR10-2016-0024217 A (published on March 23, 2014)

It is an object of the present invention to provide a linear compressor capable of suppressing generation of suction loss or compression loss due to overheat of a refrigerant compressed by the refrigerant in the compression space or a refrigerant sucked into the compression space by the cylinder and the piston heated by the refrigerant I'm trying to.

It is another object of the present invention to provide a linear compressor capable of preventing conduction of heat between a discharge cover and a frame so as to suppress heating of the frame by the discharge cover.

It is another object of the present invention to provide a refrigerating apparatus which is capable of preventing the refrigerant discharged to the discharge space of the discharge cover from contacting the frame and the cylinder and suppressing the heating of the frame and the cylinder by the refrigerant discharged to the discharge cover, And to provide a linear compressor capable of increasing the linearity of the linear compressor.

In order to achieve the object of the present invention, there is provided a linear compressor in which a gas bearing is applied between a cylinder and a piston, in which a linear compressor including a heat insulating member is provided between a frame supported by the cylinder and a discharge cover coupled to the frame .

Here, the heat insulating member may be provided so that at least a part thereof is in contact with the frame and the discharge cover.

The heat insulating member may be provided so that at least a part of the heat insulating member is separated from the frame and the discharge cover.

In addition, the frame may be formed with a spacing groove that is spaced apart from the heat insulating member, and the spacing groove may be communicated with an inner space of the casing.

Further, in order to achieve the object of the present invention, there is provided an air conditioner comprising: a casing having a sealed inner space; A linear motor provided in an inner space of the casing and reciprocating with respect to the stator; A cylinder located inside the linear motor and forming a compression space; A piston provided inside the cylinder and varying the volume of the compression space while reciprocating with the mover; At least one discharge cover having a discharge space for receiving the refrigerant discharged from the compression space; A frame in which the cylinder is inserted and fixed, and the discharge cover is coupled to a front surface; And a heat insulating cover which is provided between the discharge cover and the frame and which is separated from the discharge space of the discharge cover so that at least one heat insulating space portion communicating with the internal space of the casing is formed between the discharge cover and the frame May be provided.

Here, at least a part of the heat insulating cover is provided to be in contact with the discharge cover and the frame, and at least a part of the heat insulating space part may be formed to be included in the discharge space range of the discharge cover.

At least one spacing groove may be formed on the front surface of the frame facing the discharge cover, and the heat insulating cover may overlap the spacing grooves of the frame to form the heat insulating space.

A space sealing member is provided on the front surface of the frame to form an inner rim constituting an inner rim of the spacing groove and to be in close contact with the heat insulating cover around the outer circumferential surface of the inner rim to seal the inside of the heat insulating space .

The heat insulating cover may be provided so as to be at least partially overlapped with the cylinder in the radial direction.

A cover seating surface having a predetermined depth may be formed on the outer circumferential surface on the front side of the cylinder, and a space sealing member may be provided on the cover seating surface to seal the inside of the heat insulating space.

The front surface of the cylinder may be provided with a space portion sealing member which is in close contact with the heat insulating cover to seal the inside of the heat insulating space portion.

The heat insulating cover may be recessed toward the discharge space to form the heat insulating space.

The heat insulating cover may be formed of a material having a thermal conductivity lower than that of the discharge cover.

The discharge cover may further include a gas bearing for guiding a part of the refrigerant discharged to the discharge space between the cylinder and the piston and lubricating the space between the cylinder and the piston with the refrigerant.

In addition, a bearing inlet groove constituting an inlet of the gas bearing is formed in the heat insulating space portion of the frame, and a bearing which surrounds the bearing inlet groove and seals the bearing inlet groove with respect to the heat insulating space portion is formed around the bearing inlet groove A sealing member may be provided, and the bearing sealing member may be in close contact with the heat insulating cover.

Further, in order to achieve the object of the present invention, there is provided an air conditioner comprising: a casing having a sealed inner space; A linear motor provided in an inner space of the casing and reciprocating with respect to the stator; A compression unit arranged to be spaced apart from an inner circumferential surface of the casing, the piston connected to the mover of the linear motor reciprocating in the cylinder and forming a compression space in the cylinder; A gas bearing for guiding a part of the refrigerant discharged from the compression space between the cylinder and the piston to lubricate between the cylinder and the piston; At least one discharge cover spaced from an inner circumferential surface of the casing and coupled to the compression unit, the discharge space being provided with a discharge space for receiving the refrigerant discharged from the compression space; And a heat insulating cover formed of a material having a lower thermal conductivity than that of the discharge cover and provided between the compression unit and the discharge cover, and at least a part of which is formed to be accommodated within a range of the discharge space have.

Here, the heat insulating cover may include: a first heat insulating portion contacting the compression unit and the discharge cover; And a second adiabatic portion spaced apart from the compression unit and the discharge cover and located in the discharge space of the discharge cover.

The compression unit facing the discharge cover is provided with a spacing groove spaced apart from the discharge cover, and the heat insulating cover can overlap the spacing groove.

The spacing groove can communicate with the inner space of the casing.

The linear compressor according to the present invention is provided with a heat insulating cover between the discharge cover and the frame to prevent the heat from being conducted from the discharge cover to the frame to prevent the refrigerant in the suction passage and the compression space from being overheated, .

Further, the heat insulating cover covers the front face of the frame or the front face of the cylinder to block or reduce the direct contact of the refrigerant received in the discharge cover with the frame or the cylinder, so that the frame or the cylinder is heated by the refrigerant contained in the discharge cover, Can be suppressed from being heated. The refrigerant in the suction passage and the compression space can be prevented from being overheated, thereby improving the efficiency of the compressor.

In addition, a heat insulating space is formed between the heat insulating cover and the frame, and the heat insulating space is communicated with the internal space of the casing so that the refrigerant of the suction pressure is filled in the heat insulating space, So that the efficiency of the compressor can be further increased.

1 is a longitudinal sectional view showing a linear compressor according to the present invention,
FIG. 2 is a perspective view of the discharge cover assembly shown in FIG. 1,
FIG. 3 is a perspective view of the discharge cover assembly shown in FIG. 2,
FIG. 4 is a longitudinal sectional view showing a state in which the discharge cover assembly according to FIG.
5 and 6 are a plan view showing a front side of a frame to which a cylinder is coupled in the linear compressor according to the embodiment of the present invention,
FIG. 7 is a plan view showing a state in which the heat insulating cover is coupled to the front surface of the frame in FIG. 5,
8 is a cross-sectional view taken along the line "IV-IV" showing a state in which the heat insulating cover is assembled in Fig. 7,
9 is a plan view for explaining another embodiment of the heat insulating cover according to the present invention,
10 and 11 are cross-sectional views taken along line V-V for other embodiments of the heat-insulating cover in Fig. 9,
12 is a longitudinal sectional view showing the periphery of the frame and the discharge cover for explaining another embodiment of the heat insulating cover according to the present invention,
13 is a longitudinal sectional view showing another embodiment of the assembling structure of the heat insulating cover according to the present invention,
14 and 15 are longitudinal sectional views showing an embodiment in which a heat insulating cover and a gasket are provided in the linear compressor according to the present invention.

Hereinafter, a linear compressor according to the present invention will be described in detail with reference to an embodiment shown in the accompanying drawings.

The linear compressor according to the present invention performs an operation of sucking and compressing a fluid, and discharging a compressed fluid. The linear compressor according to the present invention may be a constituent of a refrigeration cycle. Hereinafter, the fluid will be described by taking a refrigerant circulating in a refrigeration cycle as an example.

Referring to FIG. 1, the linear compressor 100 according to the present embodiment is configured such that the inner space 101 of the casing 110 forms a closed space, and the inner space 101 of the casing 110 A frame 120 that is resiliently supported by the springs 161 and 162 may be provided. A linear motor 130 is coupled to the frame 120 and the linear motor 130 is coupled to a compression unit 140 for sucking, compressing and discharging the refrigerant. Accordingly, the compression unit 140 can be coupled to the frame 120 together with the linear motor 130, and can be elastically supported with respect to the casing 110.

The casing 110 may be formed of a thermally conductive material. The heat generated in the inner space 101 of the casing 110 can be dissipated through the casing 110 to the outside.

The casing 110 includes a shell 111 having openings at both ends and formed into a substantially cylindrical shape in a substantially transverse direction, a first shell cover 112 coupled to the rear side of the shell 111, 2 shell cover 113 as shown in FIG. The first shell cover 112 is disposed on the right side of the shell 111 and the second shell cover 113 is disposed on the left side of the shell 111 Can be combined. In a broad sense, the first shell cover 112 and the second shell cover 113 may form part of the shell 111. [

The inner diameter of the shell 110 may vary according to the size of the linear motor 130. However, since the linear compressor 100 of the present embodiment excludes the oil bearings and the gas bearing is applied, (101) need not be filled with oil. Therefore, the inner diameter of the shell 110 is formed to be as small as possible, for example, to such an extent that the flange portion 122 of the frame 120, which will be described later, can be spaced apart from the inner peripheral surface 111a of the casing 110 May be desirable. Accordingly, in the linear compressor 100 according to the present embodiment, the outer diameter of the shell 111 can be formed to be very small as compared with the above-described Patent Document 1.

The first shell cover 112 is coupled to the shell 111 so as to seal the rear side of the shell 111 as described above and the suction tube 114 can be inserted and coupled to the first shell cover 112 .

A cylindrical suction side support member 116a is coupled to the inner circumferential surface of the first shell cover 112. The suction side support member 116a is coupled to the first support spring 116 of the leaf spring . And the suction guide 116b may be inserted into the suction side support member 116a. The center of the first support spring 116 is coupled to the suction guide 116b described above, while the edge of the first support spring 116 can be coupled to the back cover 134 to be described later. The rear side of the compressor main body C including the back cover 134 is elastically supported by the first support spring 116 in the radial direction of the casing 110 including the first shell cover 112 .

The suction guide 116b is formed in a cylindrical shape and communicates with the suction pipe 114 so that the refrigerant sucked through the suction pipe 114 passes through the suction guide 116b and is sucked into the suction muffler assembly 150 Lt; / RTI >

A damping member 116c made of rubber or the like may be provided between the suction side support member 116a and the suction guide 116b. Accordingly, it is possible to prevent the vibration, which may be generated in the course of suction of the refrigerant through the suction pipe 114, from being transmitted from the suction guide 116b to the suction side support member 116a.

The second shell cover 113 is coupled to the shell 111 so as to seal the front side of the shell 111 as described above and includes a discharge pipe 115 connected to the loop pipe 115a to be described later Can be inserted and combined. Accordingly, the refrigerant discharged from the compression space 103b passes through the discharge cover assembly 160, which will be described later, and is discharged through the loop pipe 115a and the discharge pipe 115 to the refrigeration cycle.

The discharge side support member 117a is coupled to the inner circumferential surface of the shell 111 where the inner side surface of the second shell cover 113 or the inner side surface of the second shell cover 113 is in contact with the discharge side support member 117a, And a second support spring 117 made of a leaf spring can be engaged.

The central portion of the second support spring 117 may be coupled by a support guide 117b, a support cover 117c and a first support bracket 117d which are coupled to a discharge cover assembly 160 to be described later. The first support bracket 117d can be inserted into the second support bracket 113a fixed to the inner circumferential surface of the second shell cover 113 and supported in the axial direction and the radial direction. The front side of the compressor main body C including the discharge cover assembly 160 which will be described later is fixed to the casing 110 including the second shell cover 113 by the second support spring 117 in the radial direction It can be resiliently supported.

Meanwhile, a frame 120 constituting a part of the compressor main body C is provided in the casing 110. The frame 120 may be coupled with a motor 141 constituted by a linear motor 130 and a cylinder 141 constituting a compression unit 140. The frame 120 can be resiliently supported with respect to the casing 110 by the first support spring 116 and the second support spring 117 together with the linear motor 130 and the compression unit 140. [

The frame 120 may include a body portion 121 formed in a cylindrical shape and a flange portion 122 extending in a radial direction from a front end of the body portion 121.

An inner stator 132 to be described later may be coupled to the outer circumferential surface of the body portion 121 and a cylinder 141 may be coupled to the inner circumferential surface of the body portion 121, respectively. An outer stator 131 to be described later is attached to the rear surface of the flange portion 122 and a discharge cover assembly 160 to be described later can be coupled to the front surface of the flange portion 122, respectively.

A bearing communicating hole 125b which penetrates from the bearing inlet groove 125a to the inner circumferential face of the body portion 121 is formed at one side of the front surface of the flange portion 122, And a bearing communicating groove 125c may be formed in the inner circumferential surface of the body portion 121 to communicate with the bearing communicating hole 125b.

The bearing communicating hole 125b is formed to be inclined toward the inner circumferential surface of the body portion 121 by a hole having a smaller cross sectional area than the bearing entrance groove 125a . The bearing communication groove 125c may be formed in an annular shape having a predetermined depth and an axial length on the inner peripheral surface of the body portion 121. [ However, the bearing communication groove 125c may be formed on the outer circumferential surface of the cylinder 141 in contact with the inner circumferential surface of the body portion 121, or may be formed on the inner circumferential surface of the body portion 121 and the outer circumferential surface of the cylinder 141, respectively.

A bearing hole 141a may be formed in the cylinder 141 corresponding to the bearing communicating groove 125c to form a nozzle part of the gas bearing. This will be described again while explaining the cylinder.

Meanwhile, the linear motor 130 may include a stator 130a and a motor 130b that reciprocates with respect to the stator 130a.

The stator 130a includes an outer stator 131 fixed to the flange portion 122 of the frame 120 and an inner stator 132 disposed inside the outer stator 131 by a predetermined gap 130c Lt; / RTI > The inner stator 132 may be inserted and coupled to the outer circumferential surface of the body portion 121 so as to surround the body portion 121 of the frame 120. [

The outer stator 131 includes a stator core 136 laminated so as to surround the coil winding body 135 and the coil winding body 135. The coil winding body 135 includes a bobbin 135a and a bobbin 135a And a coil 135b wound in the circumferential direction may be included. The cross section of the coil 135b may be circular or polygonal, and may have a hexagonal shape, for example.

In addition, the stator core 136 may be laminated with a plurality of lamination sheets radially, and a plurality of lamination blocks may be laminated along the circumferential direction.

A stator cover 137 may be provided on the other side of the outer stator 131. Accordingly, one side portion of the outer stator 131 can be supported by the frame 120, and the other side portion can be supported by the stator cover 137, respectively.

The inner stator 132 may be inserted and fixed to the outer peripheral surface of the frame 120. The inner stator 132 may be formed by stacking a plurality of laminations radially.

Meanwhile, the mover 130b may be formed of a magnet holder 133a and a magnet 133b supported by the magnet folder 133a. One end of the magnet holder 133a is coupled to the piston 142 and the other end of the magnet holder 133a is reciprocally inserted into the gap between the outer stator 131 and the inner stator 132.

The magnet 133b may be adhered and fixed to the outer circumferential surface of the magnet holder 133a or may be fixed using a separate fixing ring (not shown). The magnet 133b can reciprocate linearly together with the magnet holder 133a by the mutual electromagnetic force formed between the outer stator 131 and the inner stator 132. [

A spring supporter 138 is coupled to the other end of the magnet holder 133a together with a piston 142. A motor 130b of the linear motor 130 and a motor 130b of the compression unit 140 are connected to both sides of the spring supporter 138, A first resonance spring 139a and a second resonance spring 139b for resonating the piston 142 may be provided.

Here, the first resonance spring 139a is disposed between the rear surface of the stator cover 137 and the front surface of the spring supporter 138, the second resonance spring 139b is disposed between the rear surface of the spring supporter 138 and the back surface 134, respectively. The back cover 134 is coupled to the stator cover 137 and can support the other end of the second resonance spring 139b in the axial direction as described above. The mover 130b of the linear motor 130 and the piston 142 of the compression unit 140 are linearly moved along the axial direction by the electromagnetic force of the linear motor 130 and the elastic forces of the resonance springs 139a and 139b. So that the refrigerant can be sucked into the compression space 103b to be compressed and discharged.

On the other hand, the compression unit 140 may include a cylinder 141, a piston 142, a suction valve 143, and a discharge valve assembly 144.

The cylinder 141 is formed in a cylindrical shape so as to have a compression space 103b therein and can be inserted and fixed to the inner circumferential surface of the frame 120. [ A discharge cover assembly 160 to be described later in which refrigerant compressed in the compression space 103b is discharged is provided on the front side of the suction muffler assembly 150 to be described later in which the refrigerant is sucked into the compression space 103b Respectively.

The cylinder 141 may be provided with a remaining portion of a gas bearing for supplying a discharge gas between the cylinder 141 and the piston 142 to gas lubrication between the cylinder 141 and the piston. For example, in the cylinder 141, the compressed refrigerant, which is radially passed through the bearing communicating groove 125c and communicated with the bearing communicating groove 125c, is communicated with the inner circumferential surface of the cylinder 141 and the inner circumferential surface of the piston 142 A bearing hole 141a for guiding to the outer circumferential surface can be formed. Of course, as described above, the bearing communicating groove 125c may be formed on the outer circumferential surface of the cylinder 141, which is more advantageous from the viewpoint of processing.

The bearing hole 141a may be formed as a fine hole so that the inlet is wide and the outlet is a nozzle. And a filter (not shown) for blocking foreign matter from entering the bearing hole 141a. The filter may be a metal mesh filter or may be formed by winding a member such as a cecile. Therefore, the inlet and outlet of the bearing hole 141a may be formed individually so as to communicate with each other independently. The inlet may be formed as an annular groove, and the outlet may be formed at a predetermined distance along the annular groove.

The bearing hole 141a may be formed only on the side adjacent to the compression space 103b (hereinafter referred to as the front side) with respect to the axial center of the cylinder 141, Or may be formed on the rear side.

The piston 142 may have a cylindrical shape such that the piston 142 has a suction passage 103a therein and the front end is partially opened while the rear end is fully opened. As described above, the rear end of the piston 142, which is an open end, is connected to the magnet holder 133a and can reciprocate together with the magnet holder 133a.

A suction port 142a communicating between the suction passage 103a and the compression space 103b is formed at the front end of the piston 142. The suction port 142a is selectively provided on the front surface of the piston 142, A suction valve 143 may be provided. The refrigerant sucked into the inner space 101 of the casing 110 is discharged through the suction passage 103a and the suction port 142a of the piston 142 while opening the suction valve 143, As shown in FIG.

At the front end of the cylinder 141, a discharge valve assembly 144 for opening and closing the compression space 103b may be detachably provided.

The discharge valve assembly 144 may include a discharge valve 144a and a valve spring 144b provided on the front side of the discharge valve 144a to elastically support the discharge valve 144a. The valve spring 144b may be formed of a compression coil spring, but may be formed of a leaf spring in consideration of an occupied space or reliability. Thus, when the pressure in the compression space 103b becomes equal to or higher than the discharge pressure, the valve spring 144b is deformed forward to open the discharge valve 144a, and the refrigerant is discharged from the compression space 103b, And discharged into the first discharge space 104a of the assembly 160. [ When discharge of the refrigerant is completed, the valve spring 144b provides a restoring force to the discharge valve 144a so that the discharge valve 144a is closed.

Meanwhile, a suction muffler assembly 150 is coupled to the rear end of the piston 142 to attenuate the noise generated during the suction of the refrigerant.

The suction muffler assembly 150 includes a suction muffler 151 communicating with the internal space 101 of the casing 110 and an internal guide connected to one side of the suction muffler 151 to guide the refrigerant to the suction port 142a 152).

The suction muffler 151 is provided outside the piston 142, and a plurality of sound-deadening spaces 102 may be formed therein by the baffle. Although the suction muffler 151 may be formed of metal, it may be formed of a plastic material in consideration of weight and insulation.

The inner guide 152 may be formed in a pipe shape so as to communicate with the noise space of the suction muffler and may be inserted deeply into the suction passage 103a of the piston 142. [ The inner guide 152 may be formed in a cylindrical shape having the same inner diameters at both ends, but it may be formed larger than the inner diameter of the rear end, which is the opposite side of the inner diameter of the front end which is the discharge side.

Meanwhile, a discharge cover assembly 160 for attenuating noise generated in the process of discharging the refrigerant in the discharge space 103b may be coupled to the front surface of the frame 120. [

The discharge cover assembly 160 may be provided on the front side of the cylinder to receive the discharge valve assembly 144. For this purpose, the discharge cover assembly 160 may be fixedly coupled to the front face of the flange portion 122, which constitutes a part of the frame 120.

Here, the discharge cover assembly 160 is formed of a thermally conductive material. When the high-temperature refrigerant flows into the discharge cover assembly 160, the heat contained in the refrigerant is transferred to the casing 110 through the discharge cover assembly 160 and dissipated to the outside of the compressor.

The discharge cover assembly 160 may be composed of a single discharge cover, or may be arranged so that a plurality of discharge covers sequentially communicate with each other. In this embodiment, the case where there are three discharge covers will be described as an example.

FIG. 2 is a perspective view of the discharge cover assembly shown in FIG. 1, and FIG. 3 is a perspective view of the discharge cover assembly shown in FIG. 10 is a longitudinal sectional view showing the assembled state.

Referring to these drawings, when there are three discharge covers, a discharge space (hereinafter referred to as a first discharge space) 104a of a discharge cover (hereinafter, referred to as a first cover) 161 coupled to the frame 120, (Hereinafter referred to as the second discharge space) 104b of the second discharge cover (hereinafter referred to as the second cover) 162 which is coupled to the front side of the first discharge chamber 161 and the second discharge space 104b communicates with the discharge space (Hereinafter referred to as a third discharge space) 104c of a third discharge cover (hereinafter referred to as a third cover) 163 coupled to the front side of the cover 162. [

2, a first space portion 161a is formed in a central portion of the first cover 161, a second space portion 162a is formed in a central portion of the second cover 162, And a third space portion 163a may be formed at the center portion.

The first space portion 161a includes a first discharge space 104a for accommodating the compression space 103b and a second space portion 162a for accommodating the first discharge space 104a. And the third space portion 163a may be formed with a third discharge space 104c for accommodating the second discharge space 104b.

The first discharge space 104a selectively communicates with the compression space 103b by the discharge valve 144a and the second discharge space 104b communicates with the first discharge space 104a. And the space 104c can communicate with the second discharge space 104b. Accordingly, the refrigerant discharged in the compression space 103b passes through the first discharge space 104a, the second discharge space 104b, and the third discharge space 104c in order to attenuate the discharge noise, And can be discharged to the outside of the casing 110 through the loop pipe 115a and the discharge pipe 115 communicating with the valve unit 163a.

 Here, the second space 162a may be formed to be wider than the first space 161a so that the first space 161a can be completely accommodated in the second space 162a. The first communication hole 105a may be formed in the first space portion 161a and the first communication hole 105a may be formed in the second discharge space 104b. Accordingly, the first discharge space 104a and the second discharge space 104b can be directly communicated by the first communication hole 105a.

The second space portion 162a may be formed such that a portion of the second space portion 162a is exposed to the outside of the third space portion 163a without being completely accommodated in the third space portion 163a. If the second space portion 162a is sufficiently accommodated in the third space portion 163a, the third space portion 163a may become too large and the discharge cover assembly 160 may be enlarged, Interference with parts may occur or the size of the entire compressor may increase.

Accordingly, the third space 163a is formed to be smaller than the second space 162a, and the third space 163a is formed in the second discharge space 104b and the third space 163a of the second space 162a, And the third discharge space 104c.

To this end, the second communication hole 105b formed in the second space portion 162a and the third communication hole 105c formed in the third space portion 163a are spaced apart from each other by a predetermined distance, and the second communication hole 105b and the third communication hole 105c may be connected to each other by a connection pipe 106. [ As a result, the third space 163a is not formed too large, so that the interference with the peripheral components and the increase in the size of the entire compressor can be suppressed, and the noise attenuation effect can be further increased by the length of the coupling pipe 106 .

A part of the first space portion 161a is exposed outside the range of the second space portion 162a so that the first discharge space 104a and the second space portion 161a of the first space portion 161a 162a may be connected to each other through a separate connection pipe (not shown). In this case, as the length of the coupling pipe becomes long, the effect of attenuating noise in the first cover 161 and the second cover 162 can be further improved.

The inner diameter D11 of the first space 161a may be larger than the inner diameter D2 of the cylinder 141. In addition, the first space portion 161a may be formed to have a width enough to receive the bearing inlet groove 125a forming the inlet of the gas bearing described above.

When the second heat insulating portion 172 of the heat insulating cover 170 described later covers the bearing entrance groove 125a, a gas hole 170c may be formed in the second heat insulating portion 172. [ It is possible to communicate with the first discharge space 104a in a state where the bearing inlet groove 125a is covered by the second heat insulating portion 172 by the gas passage hole 170c.

Of course, even if the inner diameter D11 of the first space portion 161a is formed to be small enough to accommodate the inlet of the gas bearing, the first discharge space 104a may be formed separately from the bearing inlet groove 125a (Not shown), or may be formed to communicate with the bearing inlet groove 125a by radially protruding a part of the first discharge space 104a. Accordingly, the first space portion 161a and the second space portion 162a may be formed into a non-circular cross-sectional shape if necessary.

The first space portion 161a may be folded in one step in the first fixing portion 161b, which will be described later, and formed to be convex on the front side. However, it is preferable that the first space portion 161a is folded in two or more stages to form a plurality of step surfaces S1 and S2.

For example, the first space section 161a is formed with the first stepped surface S1 and the second stepped surface S2 in the order close to the frame. In the first stepped surface S1, And the discharge valve assembly is inserted into the second stepped surface S2 so as to be supported in the axial direction.

The first communication hole 105a is disposed closer to the cylinder 141 than the valve spring 144b and the flow path resistance to the refrigerant discharged from the compression space 103b to the first discharge space 104a is reduced . Thereby, the refrigerant discharged into the first discharge space 104a can quickly move to the second discharge space 104b through the first communication hole 105a.

The discharge valve assembly 144 fixed to the second stepped surface S2 is configured such that the discharge valve 144a is elastically supported by a valve spring 144b formed of a leaf spring, Thereby opening and closing the space 103b. Therefore, it is preferable that the depth D12 of the first discharge space 104a is formed to be at least larger than the thickness D3 of the discharge valve 144a.

The first cover 161 includes a first fixing portion 161b extending from the edge of the first space portion 161a and a second fixing portion 161b extending from the edge of the second space portion 162a. The second fixing portion 162b and the third cover 163 may further include a third fixing portion 163b extending from the edge of the third space portion 163a. The first cover 161 is coupled to the frame 120 by the first fixing portion 161b and the second cover 162 is coupled to the first cover 161 by the second fixing portion 162b. And the third cover 163 can be coupled to the second cover 162 by the third fixing portion 163b.

Each of the space portions 161a, 162a and 163a is convexly formed so as to have the discharge spaces 104a, 104b and 104c, respectively, while the respective fixing portions 161b, 162b and 163b May be formed in a flange shape extending radially in the respective space portions 161a, 162a, and 163a so as to be closely attached to the front surface of the flange portion 122 of the frame 120. [

The first fixing portion 161b and the second fixing portion 162b are formed to be wide and can be bolted to the flange portion 122 of the frame 120 by the same bolts in a state of overlapping each other, The first cover 163b may be formed narrower than the first and second fixing portions 161b and 162b and welded or attached to the front surface of the second cover 162 to be fixed.

The linear compressor according to this embodiment operates as follows.

That is, when a current is applied to the coil 135b of the linear motor 130, a magnetic flux is formed between the outer stator 131 and the inner stator 132. By the electromagnetic force generated by the magnetic flux, And the magnet 130b made of the magnet 133b reciprocate in a straight line at the gap between the outer stator 131 and the inner stator 132. [

Then, the piston 142 connected to the magnet holder 130b reciprocates in a straight line in the cylinder 141, and the volume of the compression space 103b is increased or decreased. At this time, when the volume of the compression space 103b is increased due to the backward movement of the piston 142, the suction valve 143 is opened so that the refrigerant in the suction passage 103a is sucked into the compression space 103b, The piston 142 compresses the refrigerant in the compression space 103b when the volume of the compression space 103b is reduced. The compressed refrigerant is discharged into the first discharge space 104a while opening the discharge valve 144a.

A part of the refrigerant discharged into the first discharge space 104a flows into the bearing hole 125a of the cylinder 141 through the bearing inlet hole 125a and the bearing communicating hole 125b and the bearing communicating groove 125c of the gas bearing, 141a to the outer peripheral surface of the piston 142 to support the piston 142 with respect to the cylinder 141. [ On the other hand, the remaining refrigerant moves to the second discharge space 104b through the first communication hole 105a, and then flows through the second communication hole 105b, the connection pipe 106, and the third communication hole 105c 3, the noise is attenuated while moving to the discharge space 104c. The refrigerant moving to the third discharge space 104c is discharged to the outside of the compressor through the loop pipe 115a and the discharge pipe 115 and is moved to the condenser of the refrigeration cycle.

At this time, motor heat is generated in the linear motor 130, and the compressed heat is received by the refrigerant discharged from the compression space 103b in the discharge cover assembly 160. [ The motor heat and the compression heat are transferred to the cylinder 141 and the piston 142 through the frame 120, respectively.

The refrigerant sucked into the compression space 103b of the cylinder 141 as well as the refrigerant sucked into the suction passage 103a of the piston 142 is heated and the suction loss or the compression loss is generated Which may reduce the efficiency of the compressor as a whole.

Particularly, when the oil bearing is applied to the linear compressor, the temperature of the compression portion can be lowered by circulating the relatively low temperature oil between the cylinder and the piston. However, when the oil bearing is excluded and the gas bearing is applied As the high-temperature refrigerant flows into the space between the cylinder and the piston, the temperature of the compressed portion further rises and the temperature rise of the refrigerant described above can be further increased.

Further, since the temperature of the discharge cover assembly is maintained at a high temperature of about 70 캜 by the refrigerant discharged from the compression space to the discharge cover assembly, the refrigerant is discharged to the discharge side of the cylinder, which is in contact with the refrigerant held in the discharge cover assembly, The temperature of the liquid also increases. Then, the temperature of the refrigerant described above may further rise, and the compressor efficiency may be lowered.

Accordingly, the linear compressor according to the present invention includes a heat insulating cover between the front surface of the frame and the discharge cover assembly facing the front cover, so that the heat of the discharge cover assembly can be prevented from being transmitted to the frame or the cylinder. This prevents overheating of the refrigerant being sucked or the refrigerant being compressed, thereby preventing suction loss or compression loss from occurring in the compression unit.

FIG. 5 is a plan view showing a front side of a frame coupled with a cylinder in the linear compressor according to FIG. 1, and FIG. 7 is a plan view showing a state in which a heat insulating cover is coupled to a front side of the frame in FIG. And Fig. 8 is a sectional view taken along the line "IV-IV" in which the heat insulating cover is assembled in Fig.

1 to 4, the heat insulating cover 170 is provided between the front surface 122b of the frame 120 and the first fixing portion 161b of the first cover 161, And can be bolted to the frame 120 together with the cover 161. The heat insulating cover 170 may be formed of a material having a thermal conductivity lower than that of the first cover 161. The heat insulating cover 170 can prevent direct contact of the first cover 161 with the frame 120 and prevent the heat contained in the first cover 161 from being transmitted to the frame 120 .

Here, the heat insulating cover 170 is formed in an annular shape, and the radial width of the heat insulating cover 170 may be formed to be substantially equal to the radial width of the first fixing portion 161b. The heat insulating cover 170 is positioned only between the frame 120 and the first fixing portion 161b so that the heat of the first cover 161 is transferred to the frame 120 through the first fixing portion 161b It is only possible to block the conduction.

However, since the first space portion 161a of the first cover 161 has an area accommodating the center portion of the front surface 122b of the frame 120, as described above, The refrigerant in the first space portion 161a is in direct contact with the frame 120 and the front surface 141b of the cylinder 141, (141) can be heated.

Accordingly, the heat insulating cover 170 according to the present embodiment is partially disposed between the frame 120 and the first fixing portion 161b to block heat transfer due to conduction, while a part of the heat insulating cover 170 covers the frame 120 and the cylinder And is positioned between the first space 141 and the first space 161a to prevent heat transfer due to convection. A portion located between the frame 120 and the first fixing portion 161b is referred to as a first heat insulating portion 171 and a portion between the frame 120 and the cylinder 141 and the first space portion 161a And the portion where it is positioned is referred to as a second heat insulating portion 172.

The first heat insulating portion 171 is formed on the outer side of the heat insulating cover 170 and the second heat insulating portion 172 is formed on the inner side of the heat insulating cover 170. The first heat insulating portion 171 is supported on an outer protruding portion 122c provided on the front surface 122b of the frame 120 to be described later while the second heat insulating portion 172 is supported on the front surface 122b of the frame 120, May be held in close contact with a space sealing member 166 provided on the front surface 122b of the frame 120 while being spaced apart from the surface 122b.

As shown in FIGS. 2 and 5, the front surface 122b of the frame 120 may be provided with an outer protrusion 122c on the radially outer side and an inner protrusion 122d on the radially inner side. The outer protrusion 122c is formed continuously along the outer edge and the inner protrusion 122d can be formed to surround the periphery of the cylinder insertion hole 123 into which the cylinder 141 is inserted. Accordingly, a spacing groove 122e, which is recessed by a predetermined depth and forms a kind of the heat insulating space V, may be formed between the outer protrusion 122c and the inner protrusion 122d.

Here, it is preferable that the spacing groove 122e constituting the heat insulating space V is formed so as to be at least partially overlapped within the range of the first discharge space 104a. For example, the inner peripheral surface of the spacing groove 122e may be formed to a position closer to the cylinder 141 than the first stepped surface S1 of the first cover 161. [ Accordingly, even if the refrigerant in the first discharge space 104a comes into contact with the heat insulating cover 170 and the heat of the refrigerant passes through the heat insulating cover 170, the heat is also clogged in the heat insulating space portion V, It is possible to effectively block transmission to the frame 120.

A part of the outer protrusion 122c corresponds to a bolt seat for supporting the discharge cover assembly 160 to the frame 120. The outer protrusion 122c forming the bolt seat surface is formed flat, The frame 122c may be formed in a thin rib shape so as to maintain the strength while reducing the weight of the frame 120. [

A communicating portion 122f for communicating the inner space 101 of the casing 110 with a portion of the outer projecting portion 122c to allow the spacing groove 122e to communicate with the inner space 101 of the casing 110, Can be formed. Accordingly, the spacing groove 122e constituting the heat insulating space V is always communicated with the internal space 101 of the casing 110, so that the refrigerant of relatively low suction pressure is filled.

Since the first protruding portion 171 or the gasket 165 of the heat insulating cover 170 is held in close contact with the outer protruding portion 122c so that the thickness of the heat insulating cover 170 It can be stably supported on the frame. Thus, leakage of the refrigerant in the first discharge space 104a can be effectively suppressed.

When the outer protrusion 122c is formed in an annular shape as described above, at least one or more refrigerant passage grooves 122g may be formed at a predetermined depth in the middle of the outer protrusion 122c. In the case where the heat insulating space portion V is formed in one annular shape, only one refrigerant passage groove 122g can be formed, but when the heat insulating space portion V is divided into a plurality of the heat insulating space portions V, At least one refrigerant passage groove 122g may be formed for each of the heat insulating space portions V of the heat exchanger.

On the other hand, the inner protrusion 122d may be formed to surround the cylinder insertion hole 123 of the frame 120 as described above.

The inner protrusion 122d may be formed such that the front surface of the inner protrusion 122d has the same height as the front surface 141b of the cylinder 141. [ However, considering that the heat insulating cover 170 surrounds the periphery of the inner protruding portion 122d, it is preferable that the height of the inner protruding portion 122d is formed to be equal to the thickness of the heat insulating cover 170. [ 7, the front surface 122b of the frame 120 is covered with the heat insulating cover 170 so that the heat insulating cover 170 is interposed between the spacing groove 122e of the frame 120 and the heat insulating cover 170. As a result, The space V may be formed.

The inner protrusion 122d may be formed as a single protrusion having one height. However, since the inner protrusion 122d is formed not only in the first discharge space 104a but also adjacent to the compression space 103b, the inner protrusion 122d is formed in a two-stage structure so that a sealing member such as an O-ring can be installed. May be desirable.

For example, as shown in Figs. 7 and 8, the inner protrusion 122d has a first inner protrusion 122d1 formed continuously from the spacing groove 122e, a second inner protrusion 122d1 extending from the first inner protrusion 122d1, And a stepped portion that is higher than the protruding portion 122d1 may be composed of the second inner protruding portion 122d2. Accordingly, a stepped surface (not shown) may be formed between the first inner protruding portion 122d1 and the second inner protruding portion 122d2.

The first sealing member insertion groove 122h is formed on the front surface of the first inside protrusion 122d1 so as to surround the second inside protrusion 122d2 and the first sealing member insertion groove 122h is formed with a space sealing The member 166 is inserted to surround the stepped surface forming the outer peripheral surface of the second inner protruding portion 122d2.

The space sealing member 166 is in close contact with the inner rear surface of the heat insulating cover 170 so that the spacing groove 122e is communicated with the first discharge space 104a formed in the first space 161a of the first cover 161 Of course, can be separated from the compression space 103b formed in the cylinder 141 and maintained in a sealed state.

On the other hand, the above-described bearing inlet groove 125a may be formed in the spacing groove 122e. As the bearing inlet groove 125a communicates with the first discharge space 104a, the bearing inlet groove 125a and the spacing groove 122e can communicate with each other. Then, since the pressure of the bearing inlet groove 125a is higher than the pressure of the spacing groove 122e, the refrigerant in the bearing inlet groove 125a can leak into the spacing groove (heat insulating space portion) 122e. Accordingly, a separate sealing member needs to be provided around the bearing inlet groove 125a.

To this end, a second sealing member insertion groove 122i is formed in the periphery of the bearing inlet groove 125a and a bearing sealing member 167 such as a small O-ring is formed in the second sealing member insertion groove 122i. Can be inserted.

Reference numeral 145 denotes a cylinder fixing ring, 170a an outer peripheral surface of the heat insulating cover, and 170b an inner peripheral surface of the heat insulating cover.

The above-described linear compressor according to the present invention has the following operational effects.

That is, the refrigerant discharged in the compression space 103b flows into the first discharge space 104a of the first cover 161. [ This refrigerant contacts the first space portion 161a constituting the first discharge space 104a to heat the first space portion 161a and the first space portion 161a is connected to the extended first fixing portion 161b, . At this time, if the first fixing portion 161b is in contact with the frame 120 facing the first fixing portion 161b, the heat of the first fixing portion 161b is conducted to the frame 120 so that the temperature of the frame 120 is raised.

However, as in the embodiment shown in FIG. 8, between the first fixing portion 161b and the front surface 122b of the frame 120, the first heat insulating portion (not shown) of the heat insulating cover 170 made of a material having a low thermal conductivity 171 are positioned, heat conduction from the first cover 161 toward the frame 120 is blocked, thereby preventing the frame 120 from being heated.

The second heat insulating portion 172 of the heat insulating cover 170 is positioned between the first space portion 161a and the front surface 122b of the frame 120 and the front surface 141b of the cylinder 141 The first discharge space 104a forming the interior of the first space portion 161a is interrupted between the front surface 122b of the frame 120 and the front surface 141b of the cylinder 141. [ The refrigerant in the first discharge space 104a can not directly contact the frame 120 or the cylinder 141 and the frame 120 or the cylinder 141 is heated directly by the refrigerant in the first cover 161 Can be suppressed.

Furthermore, a heat insulating space portion V, which is a spacing groove 122e, is formed between the second heat insulating portion 172 of the heat insulating cover 170 and the front surface 122b of the frame 120, and the heat insulating space portion V The relatively cool refrigerant flows in the inner space 101 of the casing 110 through the communication portion 122f or the refrigerant passage groove 122g. Therefore, the heat toward the frame 120 or the cylinder 141 in the first discharge space 104a is blocked in the heat-insulating space portion V so that the frame 120 and the cylinder 141 are prevented from being heated more effectively .

Thus, overheating of the refrigerant in the suction passage or the compression space can be suppressed while the temperature of the frame is maintained at about 60 DEG C or lower, whereby the suction loss and the compression loss of the refrigerant can be reduced and the efficiency of the compressor can be improved .

In the meantime, another embodiment of the heat insulating cover in the linear compressor according to the present invention is as follows. That is, in the above-described embodiment, the second heat insulating portion of the heat insulating cover covers a part of the frame, but in the present embodiment, the second heat insulating portion of the heat insulating cover covers a part of the cylinder beyond the frame.

FIG. 9 is a plan view for explaining another embodiment of the heat insulating cover according to the present invention, and FIGS. 10 and 11 are cross-sectional views taken along line V-V of FIG. 9 for another embodiment of the heat insulating cover. As shown in these drawings, the cylinder 141 according to the present embodiment is formed such that the front surface 141b thereof protrudes more toward the discharge cover assembly than the front surface 122b of the frame 120, and the cylinder 141 The cover seating surface 141c may be formed to be stepped by a predetermined depth in the axial direction on the front surface so that the second heat insulating portion 172 of the heat insulating cover 170 is supported.

The sealing member insertion groove 141d is formed in the cover seating surface 1410c in an annular shape along the outer circumferential surface of the front side of the cylinder 141 and the space sealing member 166 described above is inserted into the sealing member insertion groove 141d Can be combined.

The space sealing member 166 is brought into close contact with the inner rear surface of the heat insulating cover 170 so that the first discharge space 104a or the compression space 103b can be separated from the heat insulating space portion V. [

Even when the second heat insulating portion 172 of the heat insulating cover 170 extends beyond the frame to the cylinder as described above, the basic structure of the heat insulating cover 170 including the first heat insulating portion 171 and the frame 120 And the effect of the present invention is similar to the above-described embodiment. However, the present embodiment can prevent the refrigerant in the first discharge space 104a from being in direct contact with the frame 120 as the heat insulating cover 170 completely covers the front surface 122b of the frame 120 . In addition, as the heat insulating cover 170 partially covers the front surface 141b of the cylinder 141, the area of the cylinder 141 in which the refrigerant directly contacts the first discharge space 104a is also reduced.

Accordingly, it is possible to reduce heating of the frame 120 and the cylinder 141 by the refrigerant, thereby suppressing the overheating of the refrigerant in the compression space and the suction space.

Here, the heat insulating cover 170 may be provided by covering the entire front surface 141b of the cylinder 141. For example, when the heat insulating cover 170 covers only a part of the front surface 141b of the cylinder 141 as shown in FIG. 10, the portion not covered by the heat insulating cover 170 is still separated from the first discharge space 104a The insulation effect may be limited. However, when the heat insulating cover 170 overlaps the entire front surface 141b of the cylinder 141 as shown in FIG. 11, the heat insulating effect can be further improved without being exposed in the first discharge space 104a. In this case, however, since the discharge valve 144 is brought into contact with the heat insulating cover 170, the valve seat of the heat insulating cover 170 must be precisely machined so that leakage of the compression space 103b can be suppressed.

Meanwhile, another embodiment of the heat insulating cover in the linear compressor according to the present invention is as follows. That is, in the above-described embodiment, the heat insulating cover is formed flat and the heat insulating space is formed only on the front surface of the frame. However, in this embodiment, the heat insulating cover is formed to be recessed in the direction toward the first space, And the rear surface of the heat insulating cover 170 are formed together.

FIG. 12 is a longitudinal sectional view showing a periphery of a frame and a discharge cover for explaining another embodiment of the heat insulating cover according to the present invention, and FIG. 13 is a longitudinal sectional view showing another embodiment of the heat insulating cover according to the present invention. .

12, the heat insulating cover 170 according to the present embodiment is formed such that the second heat insulating portion 172 is recessed toward the first space portion of the first cover 161 from the first heat insulating portion 171 It may be formed by stepping or bending. Accordingly, the first heat insulating space V1 provided in the frame 120 and the second heat insulating space V2 facing the heat insulating cover 170 can be formed in an annular shape.

The basic construction of the heat-insulating cover according to the present embodiment as described above and the operation and effect of the heat-insulating cover according to the present embodiment are similar to those of the above-described embodiment. However, when the first heat insulating space V1 is formed on the front surface 122b of the frame 120 and the second heat insulating space V2 is formed on the heat insulating cover 170, V) can be increased. As a result, the amount of the refrigerant contained in the heat insulating space V increases, thereby improving the heat insulating effect. In addition, the height H of the heat insulating space V in the entire axial direction is increased, so that the heat insulating effect can be enhanced.

In the above embodiments, the front surface 122b of the frame 120 or the spacing groove 122e for forming the heat insulating space V is formed in the heat insulating cover 170. However, 13, the heat insulating space portion may be excluded.

For example, when the heat insulating cover 170 is formed of a material having a high thermal insulation property, that is, a material having a thermal conductivity lower than that of the first cover 161, a spacing groove is formed in the frame 120 or the first cover 161 The heat insulating effect can be expected by the heat insulating cover 170 alone. Therefore, the front surface 122b of the frame 120 and the heat insulating cover 170 contacting the front surface 122b may be formed flat.

In this case, a heat insulating material may be coated on the front surface 122b of the frame 120. Then, the adiabatic effect can be further enhanced. Of course, when the coated surface is formed of a material having a heat insulating property on the front surface 122b of the frame 120, a separate heat insulating cover 170 may not be provided.

The basic construction of the above-described embodiments and the operation and effect of the above embodiments are similar to those of the above-described embodiments. However, in this embodiment, the frame 120 can be easily processed or the heat insulating cover 170 can be omitted, thereby reducing the manufacturing cost.

In the above-described embodiments, the heat insulating cover is directly contacted with the front surface of the frame and is fastened with a bolt. However, as shown in FIGS. 14 and 15, (Between the heat insulating cover and the discharge cover assembly) may be further provided with a gasket 165 having higher elasticity than the heat insulating cover 170.

The gasket 165 may be formed over the entirety of the first heat insulating portion 171 and the second heat insulating portion 172 of the heat insulating cover 170 so as to have a width corresponding to that of the first heat insulating portion 171 . Accordingly, the thermal conductivity between the discharge cover assembly 160 and the frame 120 can be further reduced by the gasket 168.

100: Linear compressor 101: Suction space
102: Suction flow path 103: Compression space
104a, 104b, 104c: Discharge spaces 105a, 105b, 105c:
106: connector 110: casing
120: frame 121:
122: flange portion 122b: front face of the frame
122c: outer projecting portion 122d: inner projecting portion
122e: spacing groove 122f:
122g: refrigerant passage grooves 122h, 122i: sealing member insertion groove
130: Linear motor 130a:
130b: Mover 140: Compression unit
141: cylinder 141b: front face of the cylinder
141c: cover seat surface 141d: sealing member insertion groove
142: piston 143: suction valve
144: Discharge valve assembly 160: Discharge cover assembly
161, 162, and 163: first, second, and third covers 161a, 162a, and 163a:
161b, 162b, 163b: first, second and third fixing parts 170:
171: a first heat insulating portion 172: a second heat insulating portion
V:

Claims (15)

A casing having a sealed inner space;
A linear motor provided in an inner space of the casing and reciprocating with respect to the stator;
A cylinder located inside the linear motor and forming a compression space;
A piston provided inside the cylinder and varying the volume of the compression space while reciprocating with the mover;
At least one discharge cover having a discharge space for receiving the refrigerant discharged from the compression space;
A frame in which the cylinder is inserted and fixed, and the discharge cover is coupled to a front surface; And
And a heat insulating cover which is provided between the discharge cover and the frame and which is separated from the discharge space of the discharge cover so that at least one heat insulating space portion communicating with the internal space of the casing is formed between the discharge cover and the frame Linear compressor. The method according to claim 1,
Wherein the heat insulating cover is provided so that at least a part thereof is in contact with the discharge cover and the frame,
And at least a part of the heat insulating space portion is formed to be included in the discharge space range of the discharge cover. The method according to claim 1,
At least one spacing groove is formed on the front surface of the frame facing the discharge cover,
Wherein the heat insulating cover covers the spacing grooves of the frame to form the heat insulating space portion. The method according to claim 1,
Wherein an inner side of the frame is formed with an inner side wall which forms an inner edge of the spacing groove,
And a space portion sealing member that is in close contact with the heat insulating cover to seal the inside of the heat insulating space portion is provided around the outer circumferential surface of the inner protrusion. The method according to claim 1,
Wherein the heat insulating cover is provided so as to be at least partially overlapped with the cylinder in the radial direction. 6. The method of claim 5,
A cover seating surface having a predetermined depth is formed on the outer circumferential surface on the front side of the cylinder,
Wherein the cover seating surface is provided with a space portion sealing member which is in close contact with the heat insulating cover to seal the inside of the heat insulating space portion. 6. The method of claim 5,
And a space sealing member for sealing the inside of the heat insulating space part in close contact with the heat insulating cover is provided on a front surface of the cylinder. The method according to claim 1,
Wherein the heat insulating cover is recessed toward the discharge space to form the heat insulating space. The method according to claim 1,
Wherein the heat insulating cover is formed of a material having a thermal conductivity lower than that of the discharge cover. 10. The method according to any one of claims 1 to 9,
Further comprising a gas bearing for guiding a part of the refrigerant discharged to the discharge space of the discharge cover between the cylinder and the piston to lubricate between the cylinder and the piston with the refrigerant. 11. The method of claim 10,
A bearing inlet groove forming an inlet of the gas bearing is formed in the heat insulating space portion of the frame,
And a bearing sealing member surrounding the bearing inlet groove to seal the bearing inlet groove with respect to the heat insulating space portion is provided in the periphery of the bearing inlet groove,
And the bearing sealing member is in close contact with the heat insulating cover. A casing having a sealed inner space;
A linear motor provided in an inner space of the casing and reciprocating with respect to the stator;
A compression unit arranged to be spaced apart from an inner circumferential surface of the casing, the piston connected to the mover of the linear motor reciprocating in the cylinder and forming a compression space in the cylinder;
A gas bearing for guiding a part of the refrigerant discharged from the compression space between the cylinder and the piston to lubricate between the cylinder and the piston;
At least one discharge cover spaced from an inner circumferential surface of the casing and coupled to the compression unit, the discharge space being provided with a discharge space for receiving the refrigerant discharged from the compression space; And
And a heat insulating cover which is formed of a material having a lower thermal conductivity than the discharge cover and is provided between the compression unit and the discharge cover, and at least a part of which is formed to be accommodated within the discharge space. 13. The heat exchanger according to claim 12,
A first heat insulating portion contacting the compression unit and the discharge cover; And
And a second adiabatic portion spaced apart from the compression unit and the discharge cover and located in the discharge space of the discharge cover. 14. The method of claim 13,
Wherein the compression unit facing the discharge cover is formed with a spacing groove spaced apart from the discharge cover,
And the heat insulating cover covers the spacing groove. 15. The method of claim 14,
And the spacing groove communicates with the inner space of the casing.

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