KR101991443B1 - Linear compressor - Google Patents

Abstract

A linear compressor according to the present invention includes: 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 plate formed of a material having a lower thermal conductivity than the frame and provided on a front surface of the frame facing the discharge cover. Accordingly, heat transmission from the discharge cover to the frame is blocked, 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.

Another object of the present invention is to provide a linear compressor which can prevent the refrigerant discharged to the discharge space of the discharge cover from contacting the frame and the cylinder, thereby suppressing the heating of the frame and the cylinder and thereby increasing the efficiency of the compressor have.

In order to achieve the object of the present invention, in a linear compressor to which a gas bearing is applied between a cylinder and a piston, at least a part of the heat insulating member is provided between the discharge cover and the frame so as to prevent the frame from being heated by the discharge cover Can be provided.

Here, the heat insulating member may be inserted into the frame and integrally joined, or may be assembled after being assembled. In the case of inserting inserts, the number of sealing members can be reduced to reduce the manufacturing cost and the manufacturing can be facilitated. In the case of post-assembly, the height of the heat insulating member can be made higher than the frame so that the area of contact between the discharging cover and the frame can be minimized.

The heat insulating member may be provided with a sealing member for sealing between the discharge cover and the sealing cover, or a sealing member may be provided between the insulating cover and the frame in contact with the heat insulating member.

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 plate formed of a material having a lower thermal conductivity than the frame and provided on a front surface of the frame facing the discharge cover.

Here, a plate insertion groove having a predetermined depth may be formed on the front surface of the frame, and the heat insulation plate may be inserted and fixed to the plate insertion groove.

The heat insulator plate may be detachably inserted into the plate inserting groove, and the depth of the plate inserting recess may be smaller than the thickness of the heat insulator plate.

Here, the heat insulating plate may include a first heat insulating portion formed in an annular shape; And at least one second heat insulating part extending radially from the outer circumferential surface of the first heat insulating part.

A sealing member insertion groove may be formed on one side of the first heat insulating portion facing the discharge cover, and a sealing member which is in close contact with the discharge cover may be inserted into the sealing member insertion groove.

The first adiabatic portion may be formed so that at least a portion thereof overlaps with a discharge space range of the discharge cover.

In the frame, a bearing inlet groove for communicating the inner peripheral surface of the cylinder and the outer peripheral surface of the piston with the discharge space of the discharge cover is formed, and a through hole communicating with the bearing inlet groove is formed in the first heat insulating portion .

A bolt hole for bolting the discharge cover to the frame may be formed in the second heat insulating portion.

Here, the heat insulating plate is formed in an annular shape, and at least one protruding surface protruding from the surface facing the discharge cover by a predetermined height and in contact with the discharge cover may be formed between the outer circumferential surface and the inner circumferential surface.

Here, a sealing member may be provided on at least one of the heat insulating plate and the discharge cover, or between the heat insulating plate and the frame.

A sealing member insertion groove may be formed on one side of the heat insulating plate facing the discharge cover to insert the sealing member.

The sealing member insertion groove may be formed on the front surface of the frame facing the heat insulating plate so that the sealing member is inserted.

A gasket having a higher elasticity than the heat-insulating plate may be provided between the discharge cover and the frame, and the gasket may be disposed to overlap the part of the heat-insulating plate in the axial direction.

The gasket may further include 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, and lubricating the cylinder and the piston with the refrigerant.

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 frame provided inside the casing; A linear motor which is supported by the frame and is provided in an internal space of the casing, the mover being reciprocated with respect to the stator; A compression unit supported on the frame so as 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 frame, the discharge space being provided with a discharge space for receiving the refrigerant discharged from the compression space; A heat insulating plate formed of a material having a thermal conductivity lower than that of the discharge cover and disposed between the frame and the discharge cover and inserted and fixed to a front surface of the frame facing the discharge cover; And a first sealing member provided between the heat insulating plate and the discharge cover and sealing the discharge space.

Here, the first sealing member insertion groove may be formed in the heat insulating plate to insert the first sealing member.

The heat-insulating plate may further include a second sealing member provided between the heat-insulating plate and the frame to seal the discharge space. At least one of the frame and the heat- The second sealing member insertion groove may be formed.

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

The heat insulating plate covers the front face of the frame or the front face of the cylinder to block or reduce the direct contact of the refrigerant accommodated in the discharge cover with the frame or the cylinder so that the frame or cylinder is cooled 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.

Also, as the heat insulating plate is inserted into the front surface of the frame, the heat transmitted from the discharge cover to the frame can be effectively blocked without increasing the axial length of the compressor due to the heat insulating plate.

In addition, the heat insulating plate can be inserted into the frame or assembled afterwards. In the case of inserting inserts, the number of sealing members is reduced to reduce the manufacturing cost and the manufacturing can be facilitated. In case of post-assembly, the height of the heat insulating member can be made higher than the frame so that the area of contact between the discharging cover and the frame can be minimized.

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.
FIG. 5 is a plan view showing a front surface of a frame coupled with a cylinder in the linear compressor according to FIG. 1,
Figs. 6 and 7C are cross-sectional views taken along the line "IV-IV" showing the assembled heat insulating plate in Fig. 5,
8 is a plan view for explaining another embodiment of the heat insulating plate according to the present invention,
9 and 10B are cross-sectional views taken along line V-V for other embodiments of the insulating plate in FIG. 8,
11 is a plan view for explaining another embodiment of the heat insulating plate 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.

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 linearly 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 the heat insulating plate between the front surface of the frame and the discharge cover assembly facing the front surface of the frame, 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 surface of a frame coupled with a cylinder in the linear compressor according to Fig. 1 according to an embodiment. Fig. 6 and Fig. 7 are sectional views of " Sectional views.

1 to 4, the heat insulating plate 170 is inserted into the front surface 122b of the frame 120 to form the first surface 122b of the frame 120 and the first surface 122b of the first cover 161, And may be provided between the first and second portions 161a and 161b. The heat insulating plate 170 may be formed in such a manner that the heat insulating plate 170 is insert-injected into the plate inserting groove 122f of the frame 120 or may be separately assembled and reassembled in a later-described plate inserting groove 122f. This will be explained later.

The heat insulating plate 170 may be made of a material having a thermal conductivity lower than that of the first cover 161, such as plastic. Accordingly, the heat insulating plate 170 completely or partially suppresses the direct contact of the first cover 161 with the frame 120, so that the heat contained in the first cover 161 is transmitted to the frame 120 You can block things.

The heat insulating plate 170 may be formed in the same shape as the front surface 122b of the frame 120 to cover the entire front surface 122b of the frame 120. [ However, when the heat insulating plate 170 is formed to be large enough to cover the entire front surface 122b of the frame 120 because the strength of the heat insulating material is weaker than that of the frame 120, the proportion of the frame 120 is small . Therefore, in order to secure the strength of the frame 120, the thickness of the heat insulating plate 170 increases and the compressor must be enlarged, or a high-strength heat insulating plate must be used, resulting in cost loss. Therefore, it may be desirable to form the frame 120 so as to maximize the heat insulating performance while maintaining the strength of the frame 120.

In addition, the heat insulating plate 170 may be installed between the front cover 122 and the discharge cover assembly 160 outside the frame 120, but in this case, the stability against the heat insulating plate 170 may be reduced. Therefore, it is stable to insert and fix the heat insulating plate 170 on the front surface 122b of the frame 120. [

For example, as shown in FIGS. 2 and 5, the front surface 122b of the frame 120 may be formed 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.

The recess 122d is formed between the inner side of the recess 122d and the inner side of the recess 122e so as to be spaced apart from the outer side wall 122c by a predetermined depth. The plate insertion groove 122f may be formed such that the plate insertion groove 122f is recessed by a depth at which the insertion hole 171 can be inserted. The depth of the plate insertion groove 122f may be deeper than the spacing groove 122e.

The depth of the plate inserting groove 122f may be different depending on the method of forming the heat insulating plate 170. For example, when the heat insulating plate 170 is insert-molded, the depth of the plate inserting groove 122f should be at least equal to or greater than the thickness of the heat insulating plate 170. So that the molten metal does not flow out during the molding of the heat insulating plate 170. On the other hand, when the heat insulating plate 170 is detachably assembled and reassembled into the plate inserting groove 122f, the depth of the plate inserting groove 122f need not be larger than the thickness of the heat insulating plate 170. [ Rather, it is advantageous in terms of heat insulation that the depth of the plate insertion groove 122f is formed to be smaller than the thickness of the heat insulating plate 170. [

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

Here, the outer protruding portion (hereinafter, referred to as a first outer protruding portion) 122c1 forming the bolt seat surface is formed with a groove having a predetermined depth to insert the second heat insulating portion 172 of the heat insulating plate 170 to be described later Or may be formed in the form of a thin rim surrounding the second insulating portion 172 to be separated from the spacing groove 122e. On the other hand, the outer projecting portion 122c2 (excluding the bolt seat surface) may be formed to protrude from the spacing groove 122e by a predetermined height.

A part of the outer protrusion 122c is communicated with the inner space 101 of the casing 110 so that the spacing groove 122e can communicate with the inner space 101 of the casing 110. [ The space 122e may be filled with the refrigerant at a relatively low suction pressure while being always in communication with the inner space 101 of the casing 110, so that a kind of heat insulating space portion may be formed.

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. [

The plate inserting groove 122f includes a first plate inserting groove 122f1 into which a first heat insulating portion 171 is inserted and a second plate inserting groove 122f2 into which a second heat insulating portion 172 is inserted Lt; / RTI >

The first plate insertion groove 122f1 may be formed between the outer protrusion 122c and the inner protrusion 122d or exactly between the inner protrusion 122d and the spacing groove 122e as described above. The plate insertion groove 122f may be formed with a thin separation protrusion 122g between itself and the spacing groove 122e so as to be separated from the spacing groove 122e. However, since the plate insertion groove 122f is formed in the same shape as the heat-insulating plate 170 as a whole, a detailed description thereof will be given instead of the description of the heat-insulating plate.

The heat insulating plate 170 according to the present embodiment is preferably made of a material having a lower thermal conductivity than the discharge valve assembly 160 or the frame 120 because heat insulating effect can be enhanced.

The heat insulating plate 170 may be formed in an annular shape as a whole. However, in some cases, they may be formed in an arc shape and arranged at regular intervals along the circumferential direction.

2 and 5, the heat insulating plate 170 includes a first heat insulating portion 171 formed in an annular shape, a second heat insulating portion 171 extending in the radial direction from the outer peripheral surface of the first heat insulating portion 171, 172).

The first heat insulating portion 171 has a width in the radial direction from the point where the first space portion 161a of the first cover 161 and the first fixing portion 161b are connected to the middle of the first fixing portion 161b As shown in FIG. Accordingly, the outer peripheral surface 171a and the inner peripheral surface 171b of the first heat insulating portion 171 can be located outside the range of the first discharge space 104a. However, the inner peripheral surface 171b of the first heat insulating portion 171 may be formed to be located within the range of the first discharge space 104a. This will be described later in another embodiment.

The front surface 171c and the rear surface 171d of the first heat insulating portion 171 may be formed flat. A first sealing member 166a such as an O-ring is inserted into the front surface 171c facing the first cover 161 from the front surface 171c and the rear surface 171d, The groove 171e may be formed between the outer peripheral surface 171a and the inner peripheral surface 171b. The first sealing member 166a is inserted into the front surface 171c of the heat insulating plate 170 and is brought into close contact with the first fixing portion 161b of the first cover 161, Can be sealed by the first sealing member 166a.

The rear surface 171d of the first heat insulating portion 171 can be brought into tight contact with the plate insertion groove 122f of the frame 120. [ Thus, a separate sealing member is not provided between the rear surface 171d of the first heat insulating portion 171 and the bottom surface of the plate insertion groove 122f facing the rear surface 171d, 104a may be sealed.

However, a sealing member may be provided between the rear surface 171d of the first heat insulating portion 171 and the bottom surface of the plate insertion groove 122f according to the method of forming the heat insulating plate 170. [ For example, in the case where the heat insulating plate 170 is integrally formed in the plate inserting groove 122f by the insert injection method as shown in FIG. 6, the first heat insulating portion 171 is in close contact with the plate inserting groove 122f , And a separate sealing member may not be required on the rear surface 171d of the first heat insulating portion 171. [

7A to 7C, when the heat insulating plate 170 is separately manufactured and is coupled to the plate inserting groove 122f in a rear assembling manner, the first insulator 171 and the plate inserting groove 122f The refrigerant in the first discharge space 104a may leak. Therefore, the second sealing member 166b is provided between the first heat insulating portion 171 and the first plate inserting groove 122f1 so that the refrigerant in the first discharge space 104a flows into the first heat insulating portion 171, It is possible to restrain leakage to the plate insertion groove 122f1.

The installation position of the second sealing member 166b can be determined in consideration of the width of the first heat insulating portion 171. [ For example, when the width of the first heat insulating portion 171 is narrow, the second sealing member 166b is inserted into the second sealing member insertion groove (not shown) provided on the bottom surface of the first plate insertion groove 122f1 The second sealing member inserting groove 122h2 provided on the inner surface of the first plate inserting groove 122f1 as shown in Fig. 7b or the second sealing member inserting groove 122h2 inserted into the first plate inserting groove 122f1, 122h1 and tightly contacted with the rear surface 171d of the first heat insulating portion 171, And may be in close contact with the inner circumferential surface 171b of the first heat insulating portion 171. In the case of FIG. 7B, since the inner diameter of the second sealing member 166b is small, assembly is easy and reliability can be improved.

7C, the second sealing member 166b is inserted into the second sealing member insertion groove 171f provided on the rear surface 171d of the first heat insulating portion 171 and inserted into the first plate insertion groove 122f1, It may be made to be in close contact with the bottom surface. The embodiment of Figure 7c may be advantageous in terms of modularity compared to the embodiment of Figures 7a and 7b.

As described above, according to the present embodiment, as the heat insulating plate 170 is back-assembled to the frame 120, the second external protruding portion 122c2, as well as the first embodiment for molding the heat insulating plate 170, It is not necessary to form the outer projection 122c1 at a high height. Accordingly, the height of the heat insulating plate 170 is made higher than that of the frame 120, so that the contact area between the first cover 161 and the frame 120 can be minimized.

In the present embodiment, since the bearing inlet groove 125a is positioned inside the inner peripheral surface 171b of the heat insulating plate 170, the bearing inlet groove 125a and the first discharge space 104a can communicate with each other . Therefore, it is not necessary to provide a separate sealing member around the bearing inlet groove 125a.

It is preferable that the second insulating portion 172 is formed at a portion where the first cover 161 and the frame 120 are most widely contacted. That is, the portion of the first cover 161 that contacts the frame 120 most widely is the bolt supporting surface, It may be desirable to be formed in the position. Therefore, the second heat insulating portion 172 may be formed at an interval of about 120 degrees along the circumferential direction at the outer peripheral surface 171a of the first heat insulating portion 171. [

A bolt hole 172a may be formed in the second heat insulating portion 172 to bolt the first cover 161 and the frame 120 with the second heat insulating portion 172 interposed therebetween.

However, the bolt hole may be unnecessary in some cases. For example, when the heat insulating plate 170 is formed by the insert injection method, the side surface of the heat insulating plate 170 is formed to be inclined so that the heat insulating plate 170 is not detached from the plate inserting groove 122f without being bolted thereto . At this time, the second heat insulating portion 172 can be inserted into the plate inserting groove 122f to prevent the heat insulating plate 170 from being turned in the circumferential direction.

2 and 4, a separate heat insulating member such as a gasket 165 may be further disposed between the first cover 161 and the frame 120, which are in contact with the second heat insulating portion 172. The second outer protrusion 122c2 not included in the heat insulating plate 170 is directly contacted with the first cover 161 by the gasket 165 so that the heat of the discharge cover assembly 160 is transferred to the frame 120 ) Can be minimized.

Reference numeral 145 denotes a cylinder retaining ring.

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, when the heat insulating plate 165 made of a material having a low thermal conductivity is placed between the first fixing portion 161b and the front surface 122b of the frame 120, It is possible to prevent heat from being conducted in the direction of the frame 120 and to prevent the frame 120 from being heated.

Further, when the gasket 165 is provided between the first cover 161 and the frame 120 in addition to the heat insulating plate 170, it is preferable that heat is conducted from the first cover 161 to the frame 120 It is possible to effectively block the heating of the frame 120 to a minimum.

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, in the linear compressor according to the present invention, another embodiment of the heat insulating plate is as follows.

That is, in the above-described embodiment, the first heat insulating portion of the heat insulating plate is located outside the first discharge space, but in this embodiment, the first heat insulating portion of the heat insulating plate is located within the range of the first discharge space.

FIG. 8 is a plan view for explaining another embodiment of the heat insulating plate according to the present invention, and FIGS. 9 to 10B are cross-sectional views taken along line V-V of FIG. 8 for another embodiment of the heat insulating plate.

8 and 9, the heat insulating plate 170 according to the present embodiment is formed such that the inner peripheral surface 171b of the first heat insulating portion 171 extends into the range of the first discharge space 104a, 1 discharge space 104a. The inner circumferential surface 171b of the first heat insulating portion 171 is formed so as to be in contact with the inner circumferential surface of the inner protruding portion 122d, As shown in FIG.

The first annular surface 171b of the first annular surface 171b extends in the cylinder direction so that the bearing inlet groove 125a provided on the front surface 122b of the frame 120 is supported by the first annular surface 171 Can be covered. Therefore, the first heat insulating portion 171 may be provided with a gas passage 171g so that the first discharge space 104a and the bearing inlet groove 125a can communicate with each other.

Also in this case, a heat insulating member such as a gasket 165 may be provided on the outer side of the heat insulating plate 170 between the first cover 161 and the frame 120 by axially overlapping with the second heat insulating portion 172 .

The basic constitution of the heat insulating plate according to the present embodiment as described above and the operation and effect of the heat insulating plate according to the present embodiment are similar to those of the above-described embodiment. However, since the first heat insulating portion 171 of the heat insulating plate 170 covers most of the front surface 122b of the frame 120 located within the range of the first discharge space 104a, The high temperature refrigerant accommodated in the space 104a is prevented from being in direct contact with the frame 120, so that the heating of the frame 120 can be more effectively suppressed. This prevents the suction passage and the refrigerant in the compression space from being heated, thereby reducing suction loss and compression loss.

In addition, when the width of the first heat insulating portion is wide as in the present embodiment, the thickness of the heat insulating plate is made as thin as possible while the first sealing member and the second sealing member are both coupled to the heat insulating plate.

10A, a first sealing member insertion groove 171e is formed in a front surface 171c of the first heat insulating portion 171 and a second sealing member insertion groove 171f is formed in a rear surface 171d of the first heat insulating portion 171. [ Respectively. It is preferable that the first sealing member insertion groove 171d and the second sealing member insertion groove 171f are spaced apart from each other by a predetermined distance t in the radial direction.

This makes it possible to prevent the thickness of the heat insulating plate 170 from being too thick while securing the sealing members 166a and 166b on both sides of the heat insulating plate 170, So that the strength of the frame 120 can be maintained.

Meanwhile, in the above-described embodiment, the first heat insulating portion covers the front surface of the frame and blocks the frame from being heated by the refrigerant in the first discharge space. However, as shown in FIG. 10B, The first discharge passage 171 may cover part (or the entirety) of the front surface 141b of the cylinder 141 beyond the frame 120 to block the refrigerant in the first discharge space 104a from the cylinder 141 to the cylinder 141. [ However, in this case, as the frame 120 and the cylinder 141 are separated from each other, the heat insulating plate 170 can not be formed by insert injection. Therefore, in this case, sealing members 166a and 166b must be provided on the front surface 171c and the rear surface 171d of the heat insulating plate 170 to effectively prevent the refrigerant in the first discharge space 104a from leaking can do.

Hereinafter, another embodiment of the heat insulating plate according to the present invention will be described. That is, in the above-described embodiments, the plurality of second heat insulating portions extend radially from the outer circumferential surface of the first heat insulating portion. However, in this embodiment, the portion constituting the second heat insulating portion is formed to be annularly extended from the outer circumferential surface of the first heat insulating portion .

11 is a plan view for explaining another embodiment of the heat insulating plate according to the present invention. As shown in the figure, the heat insulating plate 170 according to the present embodiment is formed in an annular shape having an outer circumferential surface 171a in a circular shape, and an outer circumferential surface 171a thereof is engaged with the first cover 161 and the frame 120 Position to be located outside the position.

Accordingly, the outer diameter of the heat insulating plate 170 is substantially equal to the outer diameter of the frame 120 or the outer diameter of the first cover 161 (precisely, the outer diameter of the first fixing portion) Or more.

The basic structure of the heat insulating plate according to the present embodiment as described above and the operation and effect of the heat insulating plate can be similar to those of the above-described embodiments. In this embodiment, however, the heat insulating plate 170 is positioned between the first fixing portion 161b of the first cover 161 and the front surface 122b of the frame 120, The first fixing part 161b of the first cover 161 is blocked by the first fixing part 161b of the first cover 161. This prevents heat from being transmitted to the frame 120 through the first fixing part 161b of the first cover 161 effectively.

In this embodiment, since the heat insulating plate 170 adheres to the portion of the first cover 161 that contacts the first fixing portion 161b, it is not necessary to provide a separate gasket.

Also, in the above-described embodiment, the inner peripheral surface 171b of the heat insulating plate 170 may be extended inward to a range overlapping the first discharge space 104a. In this case, since most of the front surface 122b of the frame 120 is covered with the heat insulating plate 170 or covers the front surface 141b of the cylinder 141 beyond the frame 120, the refrigerant in the suction passage, It is possible to more effectively suppress the heating of the refrigerant.

When the heat insulating plate 170 is to be reassembled, the plate inserting groove is not formed and the heat insulating plate 170 is tightly fastened to the front surface 122b of the frame 120, And fixed.

101: inner space of casing 102: noise space
103a: Suction flow path 103b: 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
122f: plate insertion groove 122f1: first plate insertion groove
122f2: second plate insertion groove 122g: separating projection
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 165: gasket
166a, 166b: first and second sealing members 170:
171: first heat insulating portion 171a: outer peripheral surface
171b: inner peripheral surface 171c: front surface
171e: first sealing member insertion groove 171d: rear face
171f: second sealing member insertion groove 171g: gas cylinder
172: second heat insulating portion 172a: bolt hole

Claims (17)

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 plate formed of a material having a lower thermal conductivity than the frame and provided on a front surface of the frame facing the discharge cover,
Wherein the heat insulating plate comprises:
A first heat insulating portion formed in an annular shape; And
And at least one second heat insulating portion extending radially from the outer circumferential surface of the first heat insulating portion. The method according to claim 1,
A plate insertion groove having a predetermined depth is formed on a front surface of the frame,
And the heat insulating plate is inserted and fixed to the plate insertion groove. 3. The method of claim 2,
Wherein the heat insulating plate is detachably inserted into a front surface of the frame,
Wherein a depth of the plate insertion groove is smaller than a thickness of the heat insulating plate. The method according to claim 1,
Wherein the first heat insulating portion is formed such that an inner circumferential side thereof overlaps with at least a part of the cylinder. The method according to claim 1,
A sealing member insertion groove is formed on one side of the first heat insulating portion facing the discharge cover,
And a sealing member in close contact with the discharge cover is inserted into the sealing member insertion groove. The method according to claim 1,
Characterized in that at least a part of the first heat insulating portion is formed so as to overlap a discharge space range of a discharge cover to which the frame contacts. The method according to claim 6,
A bearing inlet groove is formed in the frame for communicating an inner circumferential surface of the cylinder and an outer circumferential surface of the piston with a discharge space of the discharge cover,
And a through hole communicating with the bearing inlet groove is formed in the first heat insulating portion. The method according to claim 1,
And a bolt hole for bolt-tightening the discharge cover to the frame is formed in the second heat insulating portion. The method according to claim 1,
Wherein at least one protruding surface protruding from the surface facing the discharge cover by a predetermined height and in contact with the discharge cover is formed between the outer circumferential surface and the inner circumferential surface. The method according to claim 1,
And a sealing member is provided on at least one of the heat insulating plate and the discharge cover or between the heat insulating plate and the frame. 11. The method of claim 10,
And a sealing member insertion groove is formed on one side surface of the heat insulating plate facing the discharge cover to insert the sealing member. 12. The method of claim 11,
And a sealing member insertion groove is formed in a front surface of the frame facing the heat insulating plate so that the sealing member is inserted. The method according to claim 1,
A gasket having a higher elasticity than the heat-insulating plate is provided between the discharge cover and the frame,
Wherein the gasket is arranged to overlap with a part of the heat insulating plate in the axial direction. 14. The method according to any one of claims 1 to 13,
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. delete delete delete

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