WO2022173138A1

WO2022173138A1 - Linear compressor

Info

Publication number: WO2022173138A1
Application number: PCT/KR2022/000890
Authority: WO
Inventors: 이균영; 김주형; 이혁; 오원식
Original assignee: 엘지전자 주식회사
Priority date: 2021-02-15
Filing date: 2022-01-18
Publication date: 2022-08-18
Also published as: KR102494485B1; KR20220116743A

Abstract

Provided is a linear compressor comprising: a shell having an oil storage unit for accommodating oil, and forming the exterior; a cylinder installed inside the shell, and having an internal space; a piston installed in the cylinder so as to reciprocate in the inner space, and enabling a compression space to be formed in the inner space; and a discharge member having a discharge chamber communicable with the inner space therein, and installed on one side of the cylinder, wherein a heat dissipation member formed in a protruding structure is installed on one side of the shell so as to enable dissipation of heat inside the shell to the outside.

Description

linear compressor

The present invention relates to a linear compressor, and more particularly, to a linear compressor having a structure for preventing a decrease in compression efficiency due to overheating of a suction temperature.

The compressor may 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 method in which a compression space is formed between the piston and the cylinder and the piston moves linearly to compress the fluid. It is a method of compressing the fluid by rotating a pair of scrolls in engagement.

Reciprocating compressors are known in a crank method for compressing a refrigerant by converting a rotational force of a rotary motor into a linear motion, and a vibration method for compressing a refrigerant using a linear motor performing a linear reciprocating motion. A vibration-type reciprocating compressor is called a linear compressor, and such a linear compressor has advantages in that there is no mechanical loss associated with converting a rotary motion into a linear reciprocating motion, thereby improving efficiency and having a simple structure.

Patent Document 1 (Korean Patent Application No. 10-2018-0065583 (June 6, 2018)) discloses a compressor capable of reducing friction loss by reducing a substantial friction area between a cylinder and a piston.

In such a conventional linear compressor, the heat of the discharge chamber generated during compression is discharged to the outside of the shell through the discharge pipe, the heat is transmitted to the frame and cylinder in contact with the discharge chamber, and the heat is transmitted through the discharge cover.

Among them, the heat emitted to the inside causes the temperature of the suction gas to increase, thereby degrading the performance of the linear compressor.

In particular, the oil lubricating between the cylinder and the piston, which accounts for a large portion of the heat transferred through the discharge cover, and the high-temperature oil cooling the discharge cover are stored inside the shell including heat, and convective heat and A phenomenon in which the suction refrigerant filled in the shell is overheated due to radiant heat occurs, and it is required to develop a structure that can solve this problem.

The present invention has been devised to solve the above problems, and an object of the present invention is to lubricate between the cylinder and the piston, which occupies a large portion of the heat transferred through the discharge cover, and high-temperature oil to cool the discharge cover. It is to provide a linear compressor having a structure that is stored in the shell while including this heat, and has a structure that can solve the phenomenon that the suction refrigerant filled in the shell is overheated due to convective heat and radiant heat by these oils.

Another object of the present invention is to provide a heat dissipation member at a position where it can contact oil lubricated between the cylinder and the piston inside the shell, which occupies a large portion of the heat transferred through the discharge cover, and high-temperature oil that has cooled the discharge cover. To provide a linear compressor having a structure that is installed, the oil inside the shell can improve heat transfer to the outside.

Another object of the present invention is to transfer heat from the high-temperature cylinder of the discharge chamber to the piston so that the intake gas in the piston may be overheated. An object of the present invention is to provide a linear compressor having a structure capable of reducing suction loss by preventing overheating (preheating) of the refrigerant.

In order to solve the above problems, the linear compressor of the present invention is provided with an oil storage unit for accommodating oil, a shell forming an external appearance; a cylinder installed inside the shell and having an internal space; a piston installed in the cylinder so as to reciprocate in the inner space, and enabling a compression space to be formed in the inner space; and a discharge member provided at one side of the cylinder and having a discharge chamber communicateable with the inner space therein, wherein one side of the shell protrudes so as to allow the internal heat of the shell to be discharged to the outside. A heat dissipation member formed of is installed.

According to an example related to the present invention, the heat dissipation member is disposed inside the shell, a first heat dissipation fin formed to protrude in one direction, is connected to the first heat dissipation fin, and is disposed outside the shell, and a second heat dissipation fin formed to protrude in a direction opposite to the one direction.

In addition, the first heat dissipation fin is formed to protrude in the inner direction of the shell, and the second heat dissipation fin is formed to protrude toward the outside of the shell.

In addition, the heat dissipation member may further include a fin support portion disposed between the first and second heat dissipation fins in a direction crossing the one direction and supporting the first and second heat dissipation fins.

A length of the first heat dissipation fin protruding in one direction may be longer than a length of the second heat dissipation fin protruding in a direction opposite to the one direction.

A plurality of first and second heat dissipation fins may be provided, respectively, and an oil flow path for allowing the oil to flow may be provided between the first heat dissipation fins.

Preferably, the first heat dissipation fin extends in a direction crossing the one direction, and an oil suction unit for accommodating oil to be sucked in is provided between one end of the plurality of first heat dissipation fins. The first heat dissipation fins may be disposed in a radial direction.

The oil suction part may be provided in a circular or rectangular shape between one end of the plurality of first heat dissipation fins.

According to another example related to the present invention, some of the plurality of first heat dissipation fins are disposed in a radial direction, and another portion of the plurality of first heat dissipation fins crosses the one direction in the radial direction. can be placed as

The first heat dissipation fin may have a variable width along the inner direction.

An oil passage limiting flow passage through which the flow of the oil is restricted may be provided between the first heat dissipation fins, the ends of which are in contact with the oil flow limiting fins.

The heat dissipation member may be coupled to the shell by one of welding, bolting, and press-fitting.

An oil supply unit for supplying oil to the cylinder by pumping the oil contained in the oil suction unit to be suckable may be provided inside the shell.

According to another example related to the present invention, the linear compressor of the present invention can communicate with the inside of the oil supply unit to receive the oil from the oil supply unit and supply the supplied oil to the discharge member on one surface of the cylinder. and a frame having an oil supply passage connected thereto and coupled to an outer periphery of the cylinder so as to fix the cylinder, wherein oil passing through the oil supply passage can flow outside the discharge member provided around the discharge chamber .

According to another example related to the present invention, the discharge member may include: an inner discharge cover installed on one side of the cylinder to form the discharge chamber; and a discharge valve disposed in the discharge chamber and opened when the pressure in the compression space is greater than or equal to a predetermined pressure to allow a refrigerant to flow into the discharge chamber, wherein the oil passing through the oil supply passage is disposed around the inner discharge cover. can flow in

Preferably, the heat dissipation member may be coupled through the shell.

In order to solve the above another problem, the linear compressor of the present invention is provided with an oil storage unit for accommodating oil, a shell forming an appearance; a cylinder installed inside the shell and having an internal space; a piston installed in the cylinder so as to reciprocate in the inner space, and enabling a compression space to be formed in the inner space; and a discharge member provided at one side of the cylinder and having a discharge chamber communicateable with the inner space therein, wherein one side of the shell protrudes so as to allow the internal heat of the shell to be discharged to the outside. A heat dissipation member formed of is installed, the oil storage unit is provided at an inner lower portion of the shell, and the heat dissipation member is installed in the oil storage unit.

The heat dissipation member includes a first heat dissipation fin disposed inside the shell and formed to protrude in one direction, connected to the first heat dissipation fin, disposed outside the shell, and protruding in a direction opposite to the one direction The second heat dissipation fin may include a formed second heat dissipation fin and a fin support portion disposed between the first and second heat dissipation fins in a direction crossing the one direction and supporting the first and second heat dissipation fins.

The heat dissipation member may be coupled through the shell.

According to another example related to the present invention, the oil storage unit may be provided under the shell, and the heat dissipation member may be installed such that at least a portion is submerged in the oil stored in the oil storage unit.

An oil suction unit for accommodating oil to be sucked is provided between one end of the first heat dissipation fin, and the oil suction unit is disposed inside the shell to be surrounded by one end of the first heat dissipation fin. An oil supply unit for supplying oil to the cylinder by pumping the oil contained in the oil suction unit to be suckable by having an oil suction pipe is provided, the first heat dissipation fins are provided in plurality, and the plurality of first heat dissipation fins are provided. Between them, an oil flow path for allowing the oil to flow may be provided.

Preferably, the oil storage unit may be provided below the oil supply unit in the interior of the shell.

The plurality of first heat dissipation fins are disposed in a radial direction, some of the plurality of first heat dissipation fins are disposed in a radial direction, and another portion of the plurality of first heat dissipation fins is disposed in a radial direction in one direction and They may be arranged in an intersecting direction.

The plurality of first heat dissipation fins may be disposed in a radial direction.

A guide rib disposed between the plurality of first heat dissipation fins and protruded in a direction parallel to the plurality of first heat dissipation fins to guide the flow of oil may be installed in the fin support part.

A plurality of labyrinth ribs protruding from the plurality of first heat dissipation fins in a direction crossing the first heat dissipation fins may be installed in the fin support part.

A sealing member may be installed between the shell to which the heat dissipation member is coupled and the heat dissipation member to prevent oil leakage between the shell and the heat dissipation member.

an oil storage unit for accommodating oil, the shell forming an exterior; a cylinder installed inside the shell and having an internal space; a piston installed in the cylinder so as to reciprocate in the inner space, and enabling a compression space to be formed in the inner space; and a discharge member having a discharge chamber communicateable with the inner space therein, the discharge member being installed at one side of the cylinder, wherein the discharge member is installed at one side of the cylinder to form the discharge chamber discharge cover; and a discharge valve disposed in the discharge chamber and opened when the pressure of the compression space is greater than or equal to a predetermined pressure to allow a refrigerant to flow into the discharge chamber, and one side of the shell is configured to dissipate heat inside the shell to the outside. A heat dissipation member formed in a protruding structure to enable discharging to the furnace may be installed.

The heat dissipation member includes a first heat dissipation fin disposed inside the shell and formed to protrude in one direction, connected to the first heat dissipation fin, disposed outside the shell, and protruding in a direction opposite to the one direction It may include a second heat dissipation fin formed.

The heat dissipation member may further include a fin support that is disposed between the first and second heat dissipation fins in a direction crossing the one direction and supports the first and second heat dissipation fins.

The first heat dissipation fins extend in a direction crossing the one direction, and between one end of the plurality of first heat dissipation fins, an oil suction unit for accommodating oil to be sucked is provided, the plurality of first heat dissipation fins It may be arranged in a radial direction.

Preferably, some of the plurality of first heat dissipation fins may be disposed in one radial direction, and another portion of the plurality of first heat dissipation fins may be disposed in a direction crossing the one radial direction.

In the linear compressor of the present invention, the heat dissipation fin structure increases the contact area between the oil and the shell in the shell to increase the amount of heat dissipation.

In addition, the linear compressor of the present invention increases the heat transfer area (A) by mounting a heat dissipation member including the first and second heat dissipation fins in the oil storage unit having a high convective heat transfer coefficient (h) compared to the refrigerant, thereby increasing the heat transfer area (A) inside the shell. It is possible to maximize the amount of heat dissipation to the outside.

In addition, in the linear compressor of the present invention, the value of the convective heat transfer coefficient is increased due to the structure of the first heat dissipation fin in the direction toward the oil suction part in order to maximize the oil flow rate.

The linear compressor of the present invention is transferred from the inside of the shell to the shell through the first heat dissipation fin, and as the amount of heat emitted from the shell to the outside of the shell increases, the temperature of the shell rises more so that the temperature difference with the outside of the shell rises and the shell The heat transfer area is increased through the external heat dissipation fin, and the amount of convective heat transfer and radiant heat transfer between the shell and external air increases, thereby increasing the amount of heat emitted to the outside of the shell, reducing the suction refrigerant temperature, and increasing the efficiency of the linear compressor.

1 is a cross-sectional view showing a linear compressor of the present invention.

FIG. 2 is an exploded perspective view illustrating the cylinder and the piston in FIG. 1 in an exploded view;

Figure 3 is a perspective view showing the combination of the cylinder and the piston of Figure 2;

Fig. 4 is an enlarged cross-sectional view showing an example in which a heat dissipation member is installed inside the shell of the linear compressor;

Fig. 5 is a perspective view showing an example in which a heat dissipation member is provided at the bottom of the shell;

6 is a plan view of the heat dissipation member.

7 is a perspective view of a heat dissipation member.

8 is a perspective view of the heat dissipation member of FIG. 7 viewed from below;

Fig. 9 is a plan view showing an example of a heat dissipating member in which an oil suction portion is formed in an elongated rectangle in the reciprocating direction;

Fig. 10 is a plan view showing an example of a radiating member having a radial structure;

Fig. 11 is a plan view showing an example of a heat dissipation member having a labyrinth structure;

12 is a cross-sectional view showing the flow of heat emitted through the heat dissipation member and the flow of heat radiated to the outside of the shell.

13 is a table showing effects due to a heat dissipation member.

In the present specification, the same or similar reference numerals are given to the same or similar components in different embodiments, and a redundant description thereof will be omitted.

In addition, a structure applied to one embodiment may be equally applied to another embodiment as long as there is no structural and functional contradiction in the different embodiments.

The singular expression includes the plural expression unless the context clearly dictates otherwise.

In describing the embodiments disclosed in the present specification, if it is determined that detailed descriptions of related known technologies may obscure the gist of the embodiments disclosed in the present specification, the detailed description thereof will be omitted.

The accompanying drawings are only for easy understanding of the embodiments disclosed in the present specification, and the technical spirit disclosed in the present specification is not limited by the accompanying drawings, and all changes and equivalents included in the spirit and scope of the present invention It should be understood to include water or substitutes.

Hereinafter, the linear compressor 100 according to the present invention will be described in detail based on an embodiment shown in the accompanying drawings.

1 is a cross-sectional view showing the inside of a linear compressor 100 according to the present embodiment. Referring to FIG. 1 , the linear compressor 100 according to the present embodiment is provided with an oil storage unit 110c for accommodating oil, a shell 110 forming an external appearance, and an interior of the shell 110 . is installed in the cylinder 120 having an internal space, and a piston 130 installed in the cylinder 120 to enable reciprocating movement in the internal space, and to form a compression space P in the internal space, and the inside It has a discharge chamber (D) that can communicate with the space, and includes a discharge member 160 installed on one side of the cylinder (120).

In addition, a heat dissipation member 111 is installed on one side of the shell 110 to have a protruding structure to allow the heat inside the shell 110 to be radiated to the outside.

The linear compressor 100 of the present invention has a structure for preventing a decrease in compression efficiency due to overheating of the suction temperature.

In addition, the linear compressor 100 of the present invention has a structure capable of improving heat transfer to the outside of the shell 110 by using the piston 130 lubricating oil, which occupies a large portion of the heat transferred through the discharge cover. .

Hereinafter, the structure of the linear compressor 100 of the present invention will be described in more detail.

The shell 110 may be configured by combining the lower shell 110a and the upper shell 110b as shown in FIG. 1 .

The shell 110 includes a suction unit 101 through which the refrigerant is introduced and a discharge unit 105 through which the refrigerant compressed in the cylinder 120 is discharged. The discharge unit 105 may be, for example, a pipe that enables the compressed refrigerant to be discharged. The refrigerant sucked through the suction unit 101 moves to the inside of the piston 130 through the suction muffler 150 . Noise may be reduced while the refrigerant passes through the suction muffler 150 .

1, 4 and 5 show an example in which the heat dissipation member 111 is installed in the lower shell 110a.

In addition, a plan view of the heat dissipation member 111 is shown in FIG. 6 , and a perspective view of the heat dissipation member 111 is shown in FIGS. 7 and 8 .

Hereinafter, the configuration of the heat dissipation member 111 will be described with reference to FIGS. 6 to 8 .

As described above, the heat dissipation member 111 may be installed in the lower shell 110a, and more specifically, may be located in the vicinity of the suction unit 190 side, and more precisely, the suction unit 190. of the oil suction pipe 193 is partially accommodated by the heat dissipation member 111 .

In addition, the heat dissipation member 111 may be coupled to penetrate the lower shell 110a from the bottom surface of the lower shell 110a, and this structure is shown in FIGS. 1, 4 and 5 .

On the other hand, between a portion of the bottom surface of the lower shell 110a to which the heat dissipation member 111 is coupled and the heat dissipation member 111 to prevent oil leakage between the bottom surface of the lower shell 110a and the heat dissipation member 111 , It is preferable that a sealing member is installed to prevent oil from leaking from the bottom surface of the lower shell 110a to the periphery of the heat dissipation member 111 .

As shown in FIG. 6 , the heat dissipation member 111 may have a cylindrical shape having a predetermined width as a whole, and is formed to include a protruding structure that enables the heat inside the shell 110 to be discharged to the outside. will become

In addition, as a whole, each of the first and second

heat dissipation fins

111a and 111b to be described later is disposed in a radial direction, and the first and second

heat dissipation fins

111a and 111b along the circumferential direction are disposed while maintaining a preset interval. can be confirmed through FIG. 6 .

However, the shape of the heat dissipation member 111 is not necessarily limited to such a cylindrical shape structure, and a polygonal shape that enables efficient heat dissipation in consideration of the shape of the shell 110 or configurations around the heat dissipation member 111 . or any other shape.

The heat dissipation member 111 may include a first heat dissipation fin 111a and a second heat dissipation fin 111b.

The first heat dissipation fin 111a is disposed inside the shell 110 and is formed to protrude in one direction.

The second heat dissipation fin 111b is connected to the first heat dissipation fin 111a, is disposed outside the shell 110, and protrudes in a direction opposite to the one direction.

1 and 7, the first heat dissipation fin 111a may be formed to be longer than the second heat dissipation fin 111b. it is preferable

On the other hand, with respect to the arrangement structure of the second heat dissipation fins 111b, the linear compressor is installed in the machine room of the refrigerator. , may be formed in the same direction as the first heat dissipation fin.

However, the present invention is not necessarily limited to this structure, and the second heat dissipation fin 111b may be formed in a radial structure as in the arrangement of the first heat dissipation fins 311a and 411b of FIGS. 10 and 11 to be described later.

For example, the first heat dissipation fin 111a is formed to protrude inward from the inside of the shell 110 , and the second heat dissipation fin 111b protrudes toward the outside of the shell 110 in FIGS. 7 and FIG. 8 is shown in detail.

More specifically, in FIGS. 5, 7 and 8, the first heat dissipation fin 111a has a predetermined width in the circumferential direction in the shell 110, and the first heat dissipation fin 111a protrudes upwardly. has been

Similarly, in FIGS. 5, 7, and 8, from the outside of the shell 110, the second heat dissipation fin 111b has a predetermined width in the circumferential direction, and the second heat dissipation fin 111b is formed to protrude downward. .

In addition, the heat dissipation member 111 may further include a fin support 114 supporting the first and second

heat dissipation fins

111a and 111b. The fin support 114 includes the first and second heat dissipation fins 111a and 111b. ) between the first and second

heat dissipation fins

111a and 111b.

7 and 8, between the first and second

heat dissipation fins

111a and 111b, a fin support 114 supporting the first and second

heat dissipation fins

111a and 111b, and the fin support 114 are connected to the The first and second

heat dissipation fins

111a and 111b are shown.

6 to 8 , an example of the fin support 114 having a disk shape of a predetermined width is shown. As the fin support 114 is formed in a disk shape, the first and second

heat dissipation fins

111a and 111b) Since it extends to the circumferential surface of the silver disk, it may have a cylindrical shape as a whole.

Meanwhile, a plurality of first and second

heat dissipation fins

111a and 111b may be provided. An oil flow path 111c allowing oil to flow may be provided between the plurality of first heat dissipation fins 111a disposed inside the shell 110 .

7 and 8, a plurality of first heat dissipation fins 111a are arranged to be spaced apart in the circumferential direction, and an oil flow path 111c is provided between the first heat dissipation fins 111a. Each oil flow path 111c is formed in a radial direction and provided to communicate with an oil suction part 111d to be described later.

In addition, FIG. 7 shows an example in which the oil passage 111c is provided between the first heat dissipation fins 111a in the circumferential direction and is formed up to the oil suction part 111d in the radial direction.

With this structure, the oil accommodated in the oil storage unit 110c may be supplied to the oil suction unit 111d through the oil passage 111c.

Among the plurality of first heat dissipation fins 111a, between the first heat dissipation fins 111a in which the end of the first heat dissipation fin 111a is in contact with the oil flow restriction fin 113, the oil passage restricting flow path in which the flow of the oil is restricted. (111e) is provided.

An example in which an oil passage limiting passage 111e in which oil is restricted by an oil flow limiting pin 113 is provided around the oil passage 111c is shown in FIGS. 7 and 8 .

Meanwhile, an oil supply unit 190 to be described later may be connected to the oil suction unit 111d.

The oil storage unit 110c may be provided at an inner lower portion of the shell 110 , and the heat dissipation member 111 may be installed in the oil storage unit 110c. A place where the heat dissipation member 111 is installed in FIG. 5 may be understood as a place where oil is stored inside the shell 110 .

The first heat dissipation fins 111a extend in a direction crossing the one direction in which the first heat dissipation fins 111a protrude. In addition, between one end of the plurality of first heat dissipation fins 111a, the plurality of first heat dissipation fins 111a are disposed in a radial direction so that an oil suction unit 111d for accommodating oil to be sucked is provided. can

The oil accommodated in the oil suction unit 111d is pumped by the oil supply unit 190 to be described later, and the oil is supplied to the cylinder 120 .

As shown in FIG. 7 , the oil suction part 111d may be formed in a cylindrical shape having a predetermined volume inside the ends of the plurality of first heat dissipation fins 111a toward the center of the fin support part 114 .

However, it is not necessarily limited to this structure.

Meanwhile, the first heat dissipation fins 111a may have different widths along the inner direction.

In other words, referring to FIGS. 7 and 8 , the first heat dissipation fin 111a may have different widths in the central direction of the fin support 114 , and gradually inward toward the center of the fin support 114 . A wide width can be provided.

Due to the structure in which the first heat dissipation fins 111a have different widths, the speed of the oil flowing to the oil suction unit 111d may be improved, which may be understood as a direct oil suction structure.

The heat dissipation member 111 may further include an oil flow limiting fin 113 , the oil flow limiting fin 113 being disposed between some of the plurality of first heat dissipating fins 111a and the other to restrict the flow of oil. to limit

7 and 8 show an example in which four oil flow limiting pins 113 are arranged while maintaining a predetermined angle. Between the four oil flow limiting fins 113, a plurality of first heat dissipation fins 111a are disposed, some of the first heat dissipation fins 111a extend in the front and rear directions based on the drawing, and some of the first heat dissipation fins 111a extend in the left and right directions. The heat dissipation fin 111a is extended.

7 and 8, a total of 40 first

heat dissipation fins

111a and 4 oil flow limiting fins 113 are shown between them, 10 at the front, 9 on the right, 11 on the left and An example in which ten are arranged in the rear is shown.

However, the number of the first heat dissipation fins 111a is not necessarily limited to this number.

In this way, some of the plurality of first heat dissipation fins 111a are disposed in a radial direction, and other portions of the plurality of first heat dissipation fins 111a are disposed in a direction crossing the radial direction. be able to

10 each of the aforementioned front and rear are arranged in one radial direction (front-rear direction in the drawing), and 9 on the right side and 11 on the left side intersect with one radial direction (left-right direction in the drawing) can be placed as

On the other hand, an example in which the second heat dissipation fin 111b is formed to protrude outward from the outside of the shell 110 is shown in FIGS. 4 and 5 .

More specifically, in FIGS. 5, 7 and 8 , the second heat dissipation fin 111b has a predetermined width in the circumferential direction from the outside of the shell 110, and the second heat dissipation fin 111b is formed to protrude downward. has been

7 and 8, a plurality of second heat dissipation fins 111b are arranged to be spaced apart in the circumferential direction, and as described above, an oil flow path 111c is provided between the first heat dissipation fins 111a. Each oil flow path 111c is formed in a radial direction and provided to communicate with an oil suction part 111d to be described later.

With this structure, the oil accommodated in the oil storage unit 110c can be supplied to the oil suction unit 111d through the oil passage 111c, and at this time, the oil flow limiting fin from the first heat dissipation fin 111a Heat may be transferred to the second heat dissipation fin 111b through 113 , and heat is discharged from the second heat dissipation fin 111b to the outside.

The oil storage unit 110c may be provided at an inner lower portion of the shell 110 , and the heat dissipation member 111 may be installed in the oil storage unit 110c. In FIG. 5 , a place where the heat dissipation member 111 is installed may be understood as a place where oil is stored inside the lower shell 110b.

The second heat dissipation fin 111b extends in a direction crossing the one direction in which the second heat dissipation fin 111b protrudes, similarly to the structure of the first heat dissipation fin 111a.

On the other hand, the second heat dissipation fin 111b may also have different widths along the inner direction. By this structure, heat transferred from the first heat dissipation fin 111a through the oil flow limiting fin 113 is effectively discharged to the outside. will become

In other words, as shown in FIG. 8 , similarly to the structure of the first heat dissipation fin 111a , the second heat dissipation fin 111b may have different widths in the center direction of the fin support 114 , the fin support 114 . ), it is possible to gradually provide a wider width in the inner direction, which is the center direction.

7 shows an example in which four oil flow limiting pins 113 are arranged while maintaining a predetermined angle. A plurality of second heat dissipation fins 111b are disposed between the four oil flow limiting plates, and although not clearly shown in the drawing, some of the second heat dissipation fins 111b extend in the front and rear directions based on the drawing, and in the left and right directions Another part of the second heat dissipation fin 111b is extended.

As shown in FIG. 8, as described above with respect to the number of second heat dissipation fins 111b, a total of 40 second heat dissipation fins 111b and four oil flow limiting fins 113 are shown between them. It can be understood that 10 pieces are arranged on the bottom, 9 pieces on the right side, 11 pieces on the left side, and 10 pieces on the top side.

However, the number of the second heat dissipation fins 111b is not necessarily limited to this number.

In this way, like the above-described first heat dissipation fins 111a, some of the plurality of second heat dissipation fins 111b are disposed in a radial direction, and other portions of the plurality of second heat dissipation fins 111b are disposed in the radial direction. It can be arranged in a direction that intersects with one direction toward the .

Meanwhile, the heat dissipation member 111 may be coupled to the lower shell 110a by one of welding, bolting, and press-fitting. 5 shows an example in which the heat dissipation member 111 is coupled to the bottom surface of the lower shell 110a, and although it is not clearly shown which coupling method it is, it can be understood that it is coupled by one of welding, bolting, and press-fitting. have.

In addition, the heat dissipation member 111 is coupled to the lower shell 110a by one of welding, bolting and press-fitting, as described above, between a portion of the bottom surface of the lower shell 110a and the heat dissipation member 111 . It is preferable that a sealing member is installed to prevent oil from leaking from the bottom surface of the lower shell 110a to the periphery of the heat dissipation member 111 .

Meanwhile, FIG. 9 is a plan view showing an example of the heat dissipation member 211 in which the oil suction part 211d is formed in a long rectangular shape in the reciprocating direction.

Referring to FIG. 9 , a heat dissipation member 211 of another embodiment will be described.

The heat dissipation member 211 of the embodiment shown in FIG. 9 has no difference from the heat dissipation member 111 described above in the description of FIG. 6 in that the arrangement of the first heat dissipation fins 211a is arranged in the vertical and left and right directions. , the oil suction part 111d is formed in a circular structure in FIG. 6, whereas the heat dissipation member 211 in FIG. It is different from the above-described heat dissipation member 111 in that respect.

Due to this structure, when the oil supply unit 190 vibrates the oil suction pipe 193 in the reciprocating direction, the possibility of collision with the inner circumferential surface of the first heat dissipation fin 211a constituting the inner surface of the oil suction unit 211d can be minimized. do.

9, the second heat dissipation fin 211b, the oil passage 211c, the fin support 214, the oil suction portion 211d, the oil passage limiting passage 211e, and the oil flow limiting fin 213 are shown. , This configuration will be replaced with a description of the heat dissipation member 111 of FIGS. 6 to 8 .

10 is a plan view showing an example of the radiation member 311 having a radial structure.

Hereinafter, with reference to FIG. 10 , another embodiment, a heat dissipation member 311 having a radial structure will be described.

The heat dissipation member 311 of the embodiment shown in FIG. 10 is the heat dissipation member ( 111, 211) are different. The oil suction part 311d is formed in a circular structure as shown in FIG. 6 .

In the case of a radial structure in which the arrangement of the first heat dissipation fin 311a is arranged toward the vicinity of the center of the heat dissipation member 311, in the heat dissipation member 111 of the structure described above in FIG. 6 and the oil flow limiting fin 113 Since the oil passage limiting passage 111e is not provided, the flow of oil through the oil passage 311c without a clogging structure is possible.

On the other hand, in the fin support 314, a guide rib 311e disposed between the plurality of first heat dissipation fins 311a and formed to protrude in a direction parallel to the plurality of first heat dissipation fins 311a to guide the flow of oil. installed to guide the smooth flow of oil.

Meanwhile, FIG. 11 is a plan view showing an example of the heat dissipation member 411 having a labyrinth structure.

Hereinafter, with reference to FIG. 11 , another embodiment of the heat dissipation member 411 having a labyrinth structure will be described.

The heat dissipation member 411 of the embodiment shown in FIG. 11 is different from the heat dissipation member 311 described above in FIG. There is no difference. The oil suction part 411d has a circular structure as shown in FIGS. 6 and 10 .

In the case of a radiation-type structure in which the heat dissipation member 411 of such a labyrinth structure is arranged such that the arrangement of the first heat dissipation fins 411a faces near the center of the heat dissipation member 411, as described above in FIG. In the heat dissipating member 111 of the structure and the oil passage limiting flow passage 111e such as the oil flow limiting pin 113 is not provided, the oil can smoothly flow through the oil passage 411c without a clogging structure.

On the other hand, an example in which a plurality of labyrinth ribs 411e protruding from the plurality of first heat dissipation fins 411a in a direction intersecting with the first heat dissipation fins 411a are installed in the fin support 414 is shown in FIG. 11 . It allows the oil to stay for a long time to further increase the efficiency of heat transfer.

A compression space P in which the refrigerant is compressed by the piston 130 is formed in the cylinder 120 . In addition, a suction hole 131b for introducing a refrigerant into the compression space P is formed in the piston 130, and a suction valve 133 for selectively opening the suction hole 131b is provided at one side of the suction hole 131b. provided The suction valve 133 may be made of a steel plate.

A discharge member 160 for discharging the refrigerant compressed in the compression space (P) is provided on one side of the compression space (P). That is, the compression space P may be understood as a space formed between one end of the piston 130 and the discharge member 160 . Also, in the present invention, the discharge member 160 may be understood as a discharge valve assembly, which is a structure including the discharge valve 162 .

The discharge member 160 forms a discharge chamber D of the refrigerant, and the inner discharge cover 161 installed on one side of the cylinder 120 and the compression space P are opened when the pressure in the compression space P is equal to or greater than the discharge pressure. and a discharge valve 162 for introducing the refrigerant into the discharge chamber (D).

Oil passing through the oil supply passage 173 of the frame 170 to be described later is allowed to flow around the inner discharge cover 161 around the inner discharge cover 161 . For example, although not clearly shown in FIGS. 1 and 4 , an oil groove through which oil can flow may be provided on the outer periphery of the inner discharge cover 161 .

In addition, the discharge member 160 may further include a valve spring 163 provided between the discharge valve 162 and the inner discharge cover 161 to provide an elastic force in the reciprocating direction of the piston 130 . Here, the reciprocating direction of the piston 130 may be understood as "axial direction", and may also be understood as the same meaning as moving in the direction in which the piston 130 moves from side to side in FIG. 1 .

The suction valve 133 may be formed on one side of the compression space P, and the discharge valve 162 may be provided on the other side of the compression space P, that is, on the opposite side of the suction valve 133 .

In the process of the piston 130 reciprocating inside the cylinder 120, when the pressure in the compression space P is lower than the discharge pressure and less than the suction pressure, the suction valve 133 is opened and the refrigerant enters the compression space P ) is inhaled. On the other hand, when the pressure in the compression space (P) is greater than or equal to the suction pressure, the refrigerant in the compression space (P) is compressed in a state in which the suction valve 133 is closed.

On the other hand, when the pressure in the compression space (P) is equal to or greater than the discharge pressure, the valve spring 163 is deformed to open the discharge valve 162, and the refrigerant is discharged from the compression space P, and the inner discharge cover 161. of the discharge chamber (D).

Then, the refrigerant in the discharge chamber D flows into the roof pipe 164 through the inner discharge cover 161 . The inner discharge cover 161 may reduce the flow noise of the compressed refrigerant, and the loop pipe 164 guides the compressed refrigerant to the discharge unit 105 . The roof pipe 164 is coupled to the inner discharge cover 161 to extend curvedly, and is coupled to the discharge unit 105 . In addition, heat generated in the discharge chamber D during compression through the discharge unit 105 may be discharged to the outside of the shell 110 . The discharge member 160 may further include an outer discharge cover 165 coupled to the inner discharge cover 161 . The roof pipe 164 may be coupled to the outer discharge cover 165 spaced apart from the inner discharge cover 161 by a predetermined distance.

Meanwhile, the linear compressor 100 of the present invention may further include a frame 170 . The frame 170 is a member for fixing the cylinder 120 , and may be configured integrally with the cylinder 120 or may be fastened by a separate fastening member. Also, the inner discharge cover 161 may be coupled to the frame 170 .

In addition, the frame 170 includes an oil supply flow path 173 , the oil supply flow path 173 can communicate with the interior of the oil supply unit 190 to receive the oil from the oil supply unit 190 and receive the supplied oil. It is connected to one surface of the cylinder 120 so that oil can be supplied to the discharge member 160 .

As shown in FIG. 1 , the oil supply flow path 173 is formed from the lower side of the shell 110 to the upper left direction on a cross-sectional basis, but is not necessarily limited to this direction.

Oil passes through the oil supply passage 173 and can flow from the outside of the discharge member 160 provided around the discharge chamber D. To this end, a flow path formed to pass oil to enable heat dissipation and to be supplied back to the oil storage unit 110c may be provided on the outer periphery of the discharge member 160 .

In the present invention, the heat of the discharge chamber (D) generated by the compression of the piston 130 is discharged to the outside of the shell 110 through the above-described discharge portion 105 or a frame adjacent to the discharge chamber (D) Heat transfer is made through 170 and the cylinder 120 .

A heat transfer system inside and outside the shell 110 through oil in the linear compressor 100 of the present invention will be described.

1 and 12 , solid arrows show heat transfer systems inside and outside the shell 110 through oil, and dotted arrows indicate radiative convective heat transfer from the inner discharge cover 161 to the inside of the shell 110 . The system is shown.

1 and 12, the oil accommodated in the oil storage unit is pumped through the oil supply unit 190, and is provided to the end of the cylinder 120 through the oil supply passage 173 of the frame 170. . At the end of the cylinder 120 , oil flows into the discharge member 160 , and as shown in FIG. 1 , the oil introduced into the discharge member 160 is a discharge member provided around the discharge chamber (D). (160) will flow on the outer periphery.

In addition, the oil flowing from the outer periphery of the discharge member 160 is laminated on the oil storage unit 110c of the shell 110 .

In this way, the oil receives heat from the discharge chamber D in the discharge member 160 , and the heated oil is stacked on the oil storage unit 110c, and the first and second heat dissipation fins 111a of the heat dissipation member 111 are heated. , 111b) through the heat is emitted to the bottom of the shell 110.

12 shows the flow of heat emitted through the heat dissipation member 111 and the flow of heat emitted to the outside of the shell 110 in addition.

12 , as described above, heat is emitted to the outside of the shell 110 or oil flowing around the discharge member 160 is stored in the oil storage unit 110c, and the heat dissipation member 111 . An example of enabling heat to be discharged to the outside through

In this regard, in the linear compressor 100 of the present invention, the heat dissipation member 111 including the first and second

heat dissipation fins

111a and 111b in the oil storage unit 110c having a convective heat transfer coefficient (h) higher than that of the refrigerant. ) to increase the heat transfer area (A) to maximize the amount of heat dissipation from the inside of the shell 110 to the outside of the shell 110 .

In addition, due to the structure of the first heat dissipation fin 111a in the direction toward the oil suction part 111d in order to maximize the flow velocity of the oil, the value of the convective heat transfer coefficient was increased.

In addition, as the amount of heat transferred from the inside of the shell 110 to the shell 110 through the first heat dissipation fin 111a and emitted from the shell 110 to the outside of the shell 110 again increases, the As the temperature rises more, the temperature difference (ΔT) with the outside of the shell 110 increases, and the heat transfer area (A) increases through the shell 110 external heat dissipation fin, so that the convective heat transfer and radiant heat transfer between the shell 110 and external air By increasing the amount of heat emitted to the outside of the shell 110, the suction refrigerant temperature is reduced, and the efficiency of the linear compressor 100 is increased.

In relation to the emission of heat due to such conduction and radiation, the following [Equation 1] to [Equation 4] may be applied.

Regarding heat transfer due to conduction in the cylinder 120 , the discharge member 160 , and the shell 110 , [Equation 1] may be applied.

[Equation 1]

Q _cov = h * A * ΔT

In [Equation 1], Q _cov is the amount of heat transferred due to conduction, h is the convective heat transfer coefficient, A is the heat transfer area, and ΔT is the temperature difference.

[Equation 2] is a more concrete expression of [Equation 1].

[Equation 2]

Q _cov = h * A _s * (T _s - T _∞ )

In [Equation 2], Q _cov is the amount of heat transferred due to conduction, h is the convective heat transfer coefficient, A _s is the heat transfer area through which heat is conducted in the shell 110, T _s - T _∞ is the outside temperature and the shell 110 ) represents the difference between the temperatures.

Regarding the amount of heat transferred due to conduction, the thermal conductivity coefficient of refrigerant (R600a) is 0.0177 W/m-K (at 0.559 bar pressure and 32.2 ℃ temperature), and the thermal conductivity coefficient of oil is 0.18 W/m-K (based on 40 ℃ temperature) to be.

Regarding heat transfer due to radiation from the cylinder 120 , the discharge member 160 , and the shell 110 , [Equation 3] may be applied.

[Equation 3]

Q _rad = ε * A * (T _s - T _∞ )

In [Equation 3], Q _rad is the amount of heat transferred due to radiation, ε is the radiative heat transfer coefficient, A is the heat transfer area, and T _s -T _∞ is the difference between the outside air temperature and the temperature of the shell 110 .

[Equation 4]

Q _rad = σ * ε _s * _s * (T _s ⁴ - T _∞ ⁴ )

In [Equation 4], Q _rad is the amount of heat transferred due to radiation, σ is the Stefan Boltzmann constant 5.6703 * 10 ^-8 [W/(㎡ * K4)], ε _s is the radiative heat transfer coefficient, A _s is the shell (110 ), the heat transfer area through which heat is conducted, T _∞ is the outside air temperature, and T _s represents the temperature of the shell 110 .

The improvement effect by the heat dissipation member 111 will be described later.

In addition, the linear compressor 100 of the present invention may further include a motor unit 140 .

The motor unit 140 applies a driving force to the piston 130 . The motor unit 140 includes an outer stator 141 fixed to the frame 170 and disposed to surround the cylinder 120 , an inner stator 142 spaced apart from the inner side of the outer stator 141 , and the outer and a magnet 143 positioned in a space between the stator 141 and the inner stator 142 .

The magnet 143 is made of a permanent magnet and can reciprocate linearly by mutual electromagnetic force between the outer stator 141 and the inner stator 142 . And, the magnet 143 may be composed of a single magnet having one pole, or a plurality of magnets having three poles are combined.

In addition, the magnet 143 may be coupled to the piston 130 by the connecting member 144 . The connecting member 144 may extend from one end of the piston 130 to the magnet 143 . Accordingly, as the magnet 143 moves linearly, the piston 130 may linearly reciprocate in the axial direction together with the magnet 143 .

Meanwhile, the outer stator 141 includes a stator core 141a and a coil winding body 145 . A plurality of laminations are stacked in the stator core 141a in a circumferential direction, and the stator core 141a may be disposed to surround the coil winding body 145 .

As described above, in the linear compressor 100 according to the present embodiment, when a current is applied to the motor unit 140 , a current flows in the coil winding body 145 , and by the current flowing in the coil winding body 145 , A magnetic flux is formed around the coil winding body 145 , and the magnetic flux flows along the outer stator 141 and the inner stator 142 while forming a closed circuit.

The magnetic flux flowing along the outer stator 141 and the inner stator 142 and the magnetic flux of the magnet 143 interact to generate a force to move the magnet 143 .

A stator cover 146 is provided on one side of the outer stator 141 . One end of the outer stator 141 may be supported by the frame 170 , and the other end may be supported by the stator cover 146 .

The inner stator 142 is fixed to the outer periphery of the cylinder 120 . In the inner stator 142 , a plurality of stator cores are radially stacked on the outer circumferential surface of the cylinder 120 in the circumferential direction.

The linear compressor 100 further includes a supporter 181 for supporting the piston 130 and a back cover 182 extending from the piston 130 toward the suction unit 101 . The back cover 1182 may be disposed to cover at least a portion of the suction muffler 150 .

The linear compressor 100 includes a plurality of

springs

183a and 183b so that the piston 130 can resonate. The spring consists of a compression coil spring provided in the axial direction.

The plurality of

springs

183a and 183b includes a first spring 183a supported between the supporter 181 and the stator cover 146 and a second spring supported between the supporter 181 and the back cover 182 ( 183b). The elastic modulus of the first spring 183a and the second spring 183b may be the same.

Here, a position where the first spring 183a is installed may be defined as a “front” and a position where the second spring 183b is installed may be defined as a rearward. Accordingly, the front may be defined in a direction toward the compression space P or in a direction from the piston 130 toward the suction unit, and the rear as a direction away from the compression space P or in a direction from the suction unit toward the discharge member 160. .

A predetermined oil may be stored on the inner bottom surface of the shell 110 . As described above, a portion in which oil is stored on the inner bottom surface of the shell 110 may be referred to as an oil storage unit 110c. The oil storage unit 110c may be provided as a separate space enabling storage of oil on the bottom surface of the shell 110 , or may simply be accommodated on the inner bottom surface of the shell 110 without a separate space.

In addition, an oil supply unit 190 for pumping oil may be provided at a lower portion of the shell 110 .

The oil supply unit 190 makes it possible to supply oil to the cylinder 120 by pumping the oil accommodated in the oil suction part 111d of the above-described heat dissipation member 111 to be suctionable.

On the other hand, the oil supply unit 190 may be operated by vibration generated as the piston 130 reciprocates linear motion to pump oil upward. Accordingly, the oil pumped from the oil supply unit 190 is supplied to the space between the cylinder 120 and the piston 130, and performs a series of cooling and lubrication actions. In addition, the cylinder 120 is provided with an oil supply hole (128).

On the other hand, as described above, the oil supplied between the inner circumferential surface of the cylinder 120 and the outer circumferential surface of the piston 130 through the oil supply unit 190 lubricates between the inner circumferential surface of the cylinder 120 and the outer circumferential surface of the piston 130 . However, as long as the bearing contact between the inner circumferential surface of the cylinder 120 and the outer circumferential surface of the piston 130 , the friction loss between the cylinder 120 and the piston 130 still occurs.

Therefore, in order to reduce friction loss between the inner peripheral surface of the cylinder 120 and the outer peripheral surface of the piston 130 , it is preferable to minimize the friction area between the cylinder 120 and the piston 130 . However, if the friction area between the cylinder 120 and the piston 130 is unconditionally minimized, it may not be possible to stably support the deflection of the piston 130 supported in the cantilever shape by the spring due to the characteristics of the linear compressor 100 . have. Then, in a state where the concentricity of the cylinder 120 and the piston 130 does not match, the piston 130 makes a reciprocating linear motion, and in this process, the friction loss between the cylinder 120 and the piston 130 will further increase. can

This embodiment minimizes the friction area between the cylinder 120 and the piston 130 while maintaining the concentricity of the cylinder 120 and the piston 130 to reduce the friction loss between the cylinder 120 and the piston 130. is to make it

FIG. 2 is an exploded perspective view showing the cylinder 120 and the piston 130 according to FIG. 1 , and FIG. 3 is a perspective view showing the cylinder 120 and the piston 130 assembled in FIG. 2 .

As shown, the piston 130 according to the present embodiment has a substantially cylindrical shape and extends in the axial direction in the piston 130 body 131 and the piston 130 in the radial direction from the rear end of the body 131 . The piston 130 extending to the flange 132 is included.

The piston 130 body 131 includes a front portion 131a forming the front end of the piston 130 body 131 . A suction valve 133 is installed on the front part 131a. Accordingly, the refrigerant flowing in the piston 130 body 131 may be sucked into the compression space P through the suction hole 131b.

The piston 130 body 131 further includes an inclined portion 131c extending obliquely backward from the front portion 131a. The inclined portion 131c may extend in a direction in which the outer diameter of the main body 131 of the piston 130 is greater than the outer diameter of the front portion 131a. Accordingly, the piston 130 main body 131 may be inclined so that the outer diameter increases from the front part 131a to the rear by the inclined part 131c. Accordingly, when the piston 130 moves forward, a portion of the refrigerant in the compression space P moves to the front-end space formed between the inclined portion 131c and the inner circumferential surface of the cylinder 120 . Then, the refrigerant that has moved to the front-end space is gradually compressed so that the front-end of the piston 130 can be suppressed from contacting the inner circumferential surface of the cylinder 120 .

On the other hand, the piston 130 main body 131 is a bearing portion on the side of the first piston 130 in a direction away from the compression space P based on the compression space P (hereinafter, the first piston portion 135). 135 and the second piston 130-side bearing portion (hereinafter, the second piston portion 136) 136 are formed to be spaced apart by a predetermined interval.

Between the first piston part 135 and the second piston part 136, the piston 130 side avoiding part ( Hereinafter, a first avoidance portion) 137 is formed. 2 to 4 , the piston 130 side avoidance portion may be formed between the second piston portion 136 and the piston 130 flange 132 .

The outer diameter of the first piston part 135 and the outer diameter of the second piston part 136 are formed equal to each other, or the outer diameter of the first piston part 135 is slightly larger than the outer diameter of the second piston part 136. can Accordingly, the first piston unit 135 may function as a main bearing, and the second piston unit 136 may function as a sub bearing. This is to minimize leakage of the refrigerant compressed in the compression space P between the cylinder 120 and the piston 130 as the compression space P is formed on the front side of the first piston part 135 . .

The reciprocating length (or axial length) of the first piston part 135 is greater than the reciprocating length of the first cylinder 120-side bearing part to be described later, and the reciprocating length of the first cylinder 120-side bearing part and the cylinder (120) It may be formed smaller than the total length of the second sum of the reciprocating length of the side avoidance portion. This will be explained again later.

A surface where the first piston part 135 and the first avoiding part 137 meet or a surface where the first avoiding part 137 and the second piston part 136 meet may be formed as inclined surfaces 137a, respectively. Accordingly, the oil accumulated in the first avoidance part 137 may be smoothly introduced into each bearing surface along each inclined surface 137a during the reciprocating linear motion of the piston 130 .

On the other hand, the cylinder 120 is formed in a substantially cylindrical shape like the piston (130). The cylinder 120 has an inner diameter larger than the outer diameter of the piston 130 body 131 by several μm. Accordingly, the inner circumferential surface of the cylinder 120 and the outer circumferential surface of the piston 130 main body 131 are almost in contact or correspond to each other with a fine lubricating film therebetween.

The inner circumferential surface of the cylinder 120 has the first cylinder 120 side bearing part (hereinafter, the first cylinder part) 125 and the second cylinder ( 120) side bearing parts (hereinafter, second cylinder parts) 126 are formed at regular intervals. A second avoidance portion 127 is formed to extend between the first cylinder portion 125 and the second cylinder portion 126 . The inner diameters of the first cylinder part 125 and the second cylinder part 126 are formed to be substantially the same.

The first cylinder part 125 includes the first piston part 135 , the second cylinder part 126 includes the second piston part 136 , and the second avoidance part 127 includes the first avoidance part 137 and Each is formed to overlap at least a part.

However, if the overlapping section between the first cylinder part 125 and the first piston part 135 is too long, friction loss increases, whereas if the overlapping section is too short, the sealing area cannot be secured and the refrigerant in the compression space P may leak. Accordingly, the reciprocating length of the first cylinder part 125 may be at least equal to or longer than the maximum moving distance of the piston 130 . However, in consideration of the sealing area, it is preferable that the reciprocating length (A) of the first cylinder part 125 is formed to be larger than the maximum moving distance. Here, the maximum moving distance of the piston 130 is the distance that the front part 131a of the piston 130 can move the furthest from the discharge valve 162, which can be defined as a state in which the second spring 183b is fully pressed. have.

On the other hand, the reciprocating length of the first piston part 135 is formed to be larger than the reciprocating length of the second avoiding part 127 , and the reciprocating direction length of the first avoiding part 137 is that of the first cylinder part 125 . It may be formed to be larger than the reciprocating direction length. Accordingly, even if the piston 130 moves as much as the maximum movement distance, the first piston part 135 does not catch or fall off the second avoidance part 127 , so that the piston 130 smoothly reciprocates in the cylinder 120 . You can exercise.

In addition, when the reciprocating length of the first piston part 135 is too long, when the piston 130 moves by the maximum moving distance, the first piston part 135 moves to the first cylinder part 125 as well as the second cylinder part ( 126) can also be used. Then, as a whole, the contact area between the cylinder 120 and the piston 130 increases to increase the friction area as well as the rear end of the first piston part 135 to the front end of the second cylinder part 126 . The reciprocating linear motion of the piston 130 may be obstructed by being caught. Therefore, it is preferable that the reciprocating length of the first piston part 135 is smaller than the second total length of the first cylinder part 125 in the reciprocating direction and the reciprocating length of the second avoiding part 127 . Alternatively, the sum of the reciprocating length of the first piston part 135 and the maximum moving distance of the piston 130 is the reciprocating length of the first cylinder part 125 and the reciprocating length of the second avoiding part 127 . It is preferable to be formed smaller than the sum of the second total length.

In addition, when the reciprocating length of the first piston part 135 becomes longer and always comes into contact with the second cylinder part 126 , the first avoidance part 137 is covered by the second cylinder part 126 so that the oil is transferred to the first It may be prevented from flowing into the avoidance part 137 . Then, the oil may be blocked from being supplied between the second cylinder part 126 and the second piston part 136 . Therefore, the reciprocating length of the first piston part 135 is longer than the length of the first cylinder part 125 as defined above, but even when the piston 130 moves by the maximum moving distance, the second avoidance part 127 . and the first avoiding portion 137 may overlap the length, ie, it is preferable to form such that it does not exceed the second avoiding portion 127 .

In this embodiment, the first cylinder part 125, the second avoidance part 127, and the second cylinder part 126 are sequentially formed on the inner peripheral surface of the cylinder 120, and the second cylinder part 125 is formed on the inner peripheral surface of the piston 130 corresponding thereto. The first piston part 135 , the first avoiding part 137 , and the second piston part 136 may be sequentially formed.

Then, when the piston 130 reciprocates linearly with respect to the cylinder 120, the first piston part 135 is the first cylinder part 125 and the second piston part 136 is the second cylinder part ( 126) and each bearing contact.

When the piston 130 moves forward, the piston 130 moves toward the discharge valve 162 while compressing the refrigerant in the compression space P. At this time, in a state in which the first piston part 135 is in bearing contact with the first cylinder part 125 , the front side of the first piston part 135 is within the range of the first cylinder part 125 , the first piston part 135 . ) is outside the range of the first cylinder 125 by a predetermined interval. This is because the reciprocating length of the first piston part 135 is longer than the reciprocating length of the first cylinder part 125 . Therefore, even if the piston 130 moves to the discharge completion point at which the refrigerant is completely discharged, the piston 130 does not sag in the radial direction as the first piston unit 135 is supported by the first cylinder unit 125 . can be supported In this case, the second piston unit 136 is in bearing contact with the second cylinder unit 126 , so that the piston 130 can be supported more stably.

When the piston 130 moves backward, the piston 130 moves away from the discharge valve 162 while sucking the refrigerant into the compression space P. At this time, the first piston part 135 slides in a state of bearing contact with the first cylinder part 125 . And the rear side of the first piston part 135 moves toward the second cylinder part 125 . However, as the reciprocating length of the second avoiding part 127 is formed to be sufficiently long, the rear end of the first piston part 135 is always positioned inside the second avoiding part 127 . Accordingly, a distance is maintained by a predetermined distance between the rear end of the first piston part 135 and the front end of the second cylinder part 125 . Accordingly, since the first piston part 135 is not caught on the second cylinder part 125 , it is possible to prevent the reciprocation of the piston 130 from being blocked in advance.

As described above, the first avoiding part 137 is formed on the outer peripheral surface of the piston 130 and the second avoiding part 127 is formed on the inner peripheral surface of the cylinder 120 , respectively, and the first avoiding part 137 is the cylinder 120 . ), and the second avoidance portion 127 does not come into contact with the piston 130 . Accordingly, the frictional area between the cylinder 120 and the piston 130 is reduced as a whole, thereby reducing the frictional loss.

Furthermore, the contact area between the first piston part 135 and the first cylinder part 125 increases when the piston 130 performs a compression stroke. However, since the pressure of the compression space P increases during the compression stroke, it may be advantageous in terms of sealing to increase the contact area between the first piston part 135 and the first cylinder part 125 . Through this, it is possible to effectively suppress the refrigerant compressed in the compression space P from leaking to the bearing surface between the cylinder 120 and the piston 130 . On the other hand, when the piston 130 performs the suction stroke, the contact area between the first piston part 135 and the first cylinder part 125 is reduced. However, since the pressure in the compression space P is reduced when the suction stroke is performed, the compressor efficiency is not greatly affected.

When the piston 130 moves to the discharge completion point (the point at which the volume of the compression space P is 0), the pressure of the compression space P rapidly increases. Therefore, a large sealing area is required between the cylinder 120 and the piston 130 during the compression stroke. As described above, since the friction area between the first cylinder part 125 and the first piston part 135 gradually increases during the compression stroke, the refrigerant in the compression space P flows between the cylinder 120 and the piston 130 . leakage can be suppressed.

Conventionally, the bearing contact length between the cylinder 120 and the piston 130 is the same regardless of the movement distance of the piston 130, but in this embodiment, the cylinder 120 and the piston ( 130), the contact length of the bearings decreases linearly. Then, since the average friction length per cycle of the piston 130 is reduced, the friction loss between the cylinder 120 and the piston 130 is reduced, so that the compressor efficiency can be improved. In addition, through this, it is possible to suppress damage to the cylinder 120 and the piston 130 while facilitating the manufacture of the cylinder 120 or the piston 130 .

In addition, in the case of this embodiment, as the piston 130 is supported in a cantilever shape by a plurality of

springs

183a and 183b made of compression coil springs, if the support area for the piston 130 is small, the piston 130 is Deflection may occur depending on its own weight. However, as in this embodiment, the first piston part 135 and the second piston part 136 are arranged in the axial direction, and these piston 130

side bearing parts

135 and 136 are respectively connected to the first cylinder part 125 and As it is radially supported by the second cylinder part 126 , it is possible to stably support the sagging of the piston 130 . Accordingly, it is possible to suppress the deflection of the piston 130 supported in the cantilever shape while reducing the actual friction area between the cylinder 120 and the piston 130 , thereby further reducing the friction loss between the cylinder 120 and the piston 130 . can be lowered

That is, in the above-described embodiment, the first piston part 135 and the second piston part 136 in the piston 130 are spaced apart by the reciprocating length of the first avoiding part along the axial direction, but the piston At 130, only one piston 130-side bearing portion is formed.

As shown, the inner circumferential surface of the cylinder 120 according to the present embodiment is the same as in the above-described embodiment. That is, the first cylinder portion 125 and the second cylinder portion 126 are formed on the inner circumferential surface of the cylinder 120 with the second avoidance portion 127 interposed therebetween. The inner diameter of the first cylinder part 125 and the inner diameter of the second cylinder part 126 are formed to be the same, and the inner diameter of the second avoidance part 127 is formed to be larger than the inner diameter of both

cylinder parts

125 and 126 . Accordingly, the second avoiding portion 127 is formed to be recessed by a predetermined depth from the inner circumferential surface of the cylinder 120 toward the outer circumferential surface.

On the other hand, the piston 130 side bearing part 135 is formed on the outer peripheral surface of the piston 130 body 131 on the front side, and the piston 130 side bearing part 135 is formed on the rear end of the piston 130 side bearing part 135 . The piston 130 side avoidance portion 137 having an outer diameter smaller than the outer diameter of the portion 135 is formed. At the rear end of the piston 130 avoidance part 137 , the piston 130 flange 132 described above is formed. Accordingly, one piston 130-side bearing portion corresponding to the aforementioned first piston 130-side bearing portion is formed in the piston 130 body 131 according to the present embodiment.

The basic configuration of the cylinder 120 and the piston 130 according to the present embodiment as described above is substantially the same as that of the above-described embodiment. However, in this embodiment, as the piston 130 side bearing part 135 is formed only at the front end of the piston 130 body 131, the cylinder 120 and the piston 130 compared to the above-described embodiment. The friction area between them can be further reduced. Through this, the friction loss between the cylinder 120 and the piston 130 can be further reduced. In addition, since the weight of the piston 130 is reduced, compressor efficiency may be improved.

On the other hand, in the above-described embodiments, a plurality of springs are provided on the rear side of the piston 130 to induce a resonant motion of the piston 130, but the spring is not necessarily required. For example, the piston 130 may resonate by using the thrust and return force of the magnet except for the spring.

Even in this case, between the cylinder 120 and the piston 130 , the cylinder 120 side bearing part and the piston 130 side bearing part, and the cylinder 120 side avoidance part and the piston 130, respectively, as in the above-described embodiment, respectively. ) side avoidance portion can be formed. A detailed description thereof will be omitted.

13 is a table showing the improvement effect according to the reference condition of the suction port temperature, the energy efficiency ratio (EER) improvement, and the refrigerator shutdown. As shown in FIG. 13 , the suction port temperature was decreased by 1.5°C, the EER was increased by 0.06, and 0.6% was improved in relation to the refrigerator burnout.

As described above, by installing the heat dissipating member 111 in the shell 110, the heat dissipating member 111 of the shell 110 is increased, making it possible to reduce the suction refrigerant temperature.

Since oil has a convective heat transfer effect that is 10 times or more different than that of a refrigerant, the first and second

heat dissipation fins

111a and 111b are installed in the oil storage unit 110c in which the oil is accommodated to increase the heat transfer coefficient and heat dissipation surface area. , the heat dissipation effect can be maximized.

The above-described linear compressor 100 is not limited to the configuration and method of the embodiments described above, and embodiments may be configured by selectively combining all or part of each embodiment so that various modifications can be made.

It is apparent to those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit and essential characteristics of the present invention. Accordingly, the above detailed description should not be construed as restrictive in all respects but as exemplary. The scope of the present invention should be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the present invention are included in the scope of the present invention.

The present invention can be used in a linear compressor having a structure for preventing a decrease in compression efficiency due to overheating of the suction temperature.

Claims

an oil storage unit for accommodating oil, the shell forming an exterior;

a cylinder installed inside the shell and having an internal space;

a piston installed in the cylinder so as to reciprocate in the inner space, and enabling a compression space to be formed in the inner space; and

and a discharge member having a discharge chamber communicateable with the inner space therein, and a discharge member installed on one side of the cylinder,

A linear compressor characterized in that a heat dissipation member formed in a protruding structure so as to be able to dissipate heat inside the shell to the outside is installed on one side of the shell.
According to claim 1,

The heat dissipation member,

a first heat dissipation fin disposed inside the shell and formed to protrude in one direction;

and a second heat dissipation fin connected to the first heat dissipation fin, disposed outside the shell, and configured to protrude in a direction opposite to the one direction.
3. The method of claim 2,

The first heat dissipation fin is formed to protrude in the inner direction of the shell, and the second heat dissipation fin is formed to protrude toward the outside of the shell.
3. The method of claim 2,

The heat dissipation member,

and a fin support part disposed between the first and second heat dissipation fins in a direction crossing the one direction and supporting the first and second heat dissipation fins.
3. The method of claim 2,

A length of the first heat dissipation fin protruding in one direction is longer than a length of the second heat dissipation fin protruding in a direction opposite to the one direction.
3. The method of claim 2,

Each of the first and second heat dissipation fins is provided in plurality,

An oil flow path for allowing the oil to flow is provided between the first heat dissipation fins.
7. The method of claim 6,

The first heat dissipation fins extend in a direction crossing the one direction, and between one end of the plurality of first heat dissipation fins, an oil suction unit for accommodating oil to be sucked in is provided, the plurality of first heat dissipation fins include Linear compressor, characterized in that disposed in the radial direction.
8. The method of claim 7,

The oil suction part is a linear compressor, characterized in that provided in a circular or rectangular shape between one end of the plurality of first heat dissipation fins.
8. The method of claim 7,

Some of the plurality of first heat dissipation fins are disposed in a radial direction,

Another part of the plurality of first heat dissipation fins is disposed in a direction crossing the one direction toward the radial direction.
10. The method of claim 9,

The first heat dissipation fin is a linear compressor, characterized in that the width is variable along the inner direction.
5. The method of claim 4,

A linear compressor, characterized in that an oil passage limiting flow path for restricting the flow of the oil is provided between the first heat dissipation fins, the ends of which are in contact with the oil flow limiting fins.
According to claim 1,

The heat dissipation member is a linear compressor, characterized in that coupled to the shell by one of welding, bolting, and press-fitting.
8. The method of claim 7,

An oil supply unit is provided in the shell to pump the oil accommodated in the oil suction unit so as to be able to suck it and to supply the oil to the cylinder.
14. The method of claim 13,

and an oil supply passage connected to one surface of the cylinder so as to be able to communicate with the interior of the oil supply unit to receive oil from the oil supply unit and supply the supplied oil to the discharge member, and to fix the cylinder. Further comprising a frame coupled to the outer periphery,

A linear compressor, characterized in that the oil passing through the oil supply passage can flow outside the discharge member provided around the discharge chamber.
15. The method of claim 14,

The discharge member,

an inner discharge cover installed on one side of the cylinder to form the discharge chamber; and

and a discharge valve disposed in the discharge chamber and opened when the pressure in the compression space is greater than or equal to a predetermined pressure to allow the refrigerant to flow into the discharge chamber;

A linear compressor, characterized in that the oil passing through the oil supply passage can flow around the inner discharge cover.
According to claim 1,

The heat dissipation member is a linear compressor, characterized in that coupled through the shell.
an oil storage unit for accommodating oil, the shell forming an exterior;

a cylinder installed inside the shell and having an internal space;

a piston installed in the cylinder so as to reciprocate in the inner space, and enabling a compression space to be formed in the inner space; and

and a discharge member having a discharge chamber communicateable with the inner space therein, and a discharge member installed on one side of the cylinder,

At one side of the shell, a heat dissipation member formed in a protruding structure so as to be able to dissipate heat inside the shell to the outside is installed,

The oil storage unit is provided at an inner lower portion of the shell, and the heat dissipation member is installed in the oil storage unit.
18. The method of claim 17,

The heat dissipation member,

a first heat dissipation fin disposed inside the shell and formed to protrude in one direction;

a second heat dissipation fin connected to the first heat dissipation fin, disposed outside the shell, and formed to protrude in a direction opposite to the one direction;

and a fin support portion disposed between the first and second heat dissipation fins in a direction crossing the one direction and supporting the first and second heat dissipation fins.
19. The method of claim 18,

The heat dissipation member is a linear compressor, characterized in that coupled through the shell.
20. The method of claim 19,

The oil storage unit is provided at a lower portion of the shell, and the heat dissipation member is installed to be at least partially submerged in the oil stored in the oil storage unit.
20. The method of claim 19,

Between one end of the first heat dissipation fin, an oil suction unit for accommodating oil to be sucked is provided,

An oil suction pipe disposed in the oil suction unit is provided inside the shell to be surrounded by one end of the first heat dissipation fin, and the oil contained in the oil suction unit is pumped to suck the oil to supply the oil to the cylinder. A refueling unit that enables

The first heat dissipation fins are provided in plurality, and an oil flow path for allowing the oil to flow is provided between the plurality of first heat dissipation fins.
22. The method of claim 21,

The oil storage unit,

Linear compressor, characterized in that provided below the oil supply unit in the interior of the shell.
23. The method of claim 22,

The plurality of first heat dissipation fins are disposed in a radial direction,

Some of the plurality of first heat dissipation fins are disposed in a radial direction,

Another part of the plurality of first heat dissipation fins is disposed in a direction crossing the one direction toward the radial direction.
23. The method of claim 22,

The plurality of first heat dissipation fins are linear compressors, characterized in that disposed in a radial direction.
25. The method of claim 24,

The fin support is provided with a guide rib disposed between the plurality of first heat dissipation fins and protruded in a direction parallel to the plurality of first heat dissipation fins to guide the flow of oil.
25. The method of claim 24,

A plurality of labyrinth ribs protruding from the plurality of first heat dissipation fins in a direction intersecting with the first heat dissipation fins are installed in the fin support part.
20. The method of claim 19,

A sealing member is installed between the shell to which the heat dissipation member is coupled and the heat dissipation member so as to prevent oil leakage between the shell and the heat dissipation member.
an oil storage unit for accommodating oil, the shell forming an exterior;

a cylinder installed inside the shell and having an internal space;

a piston installed in the cylinder so as to reciprocate in the inner space, and enabling a compression space to be formed in the inner space; and

and a discharge member having a discharge chamber communicateable with the inner space therein, and a discharge member installed on one side of the cylinder,

The discharge member,

an inner discharge cover installed on one side of the cylinder to form the discharge chamber; and

and a discharge valve disposed in the discharge chamber and opened when the pressure in the compression space is greater than or equal to a predetermined pressure to allow the refrigerant to flow into the discharge chamber;

A linear compressor characterized in that a heat dissipation member formed in a protruding structure so as to be able to dissipate heat inside the shell to the outside is installed on one side of the shell.
29. The method of claim 28,

The heat dissipation member,

a first heat dissipation fin disposed inside the shell and formed to protrude in one direction;

and a second heat dissipation fin connected to the first heat dissipation fin, disposed outside the shell, and configured to protrude in a direction opposite to the one direction.
30. The method of claim 29,

The heat dissipation member,

and a fin support part disposed between the first and second heat dissipation fins in a direction crossing the one direction and supporting the first and second heat dissipation fins.
30. The method of claim 29,

Each of the first and second heat dissipation fins is provided in plurality,

An oil flow path for allowing the oil to flow is provided between the first heat dissipation fins.
32. The method of claim 31,

The first heat dissipation fins extend in a direction crossing the one direction, and between one end of the plurality of first heat dissipation fins, an oil suction unit for accommodating oil to be sucked in is provided, the plurality of first heat dissipation fins include Linear compressor, characterized in that disposed in the radial direction.
33. The method of claim 32,

Some of the plurality of first heat dissipation fins are disposed in a radial direction,

Another part of the plurality of first heat dissipation fins is disposed in a direction crossing the one direction toward the radial direction.