Linear compressor

Patent metadata

Field	Value
Publication number	US-11261856-B2
Application number	US-201916414114-A
Country	US
Kind code	B2
Filing date	May 16, 2019
Priority date	May 16, 2018
Publication date	Mar 1, 2022
Grant date	Mar 1, 2022

Abstract

Provided is a linear compressor including a linear motor having a mover reciprocating with respect to a stator; a piston coupled to the mover to reciprocate; a cylinder into which the piston is slidingly inserted, the cylinder having an inner circumferential surface forming a bearing surface together with an external circumferential surface of the piston, the cylinder forming a compression space together with the piston, and the cylinder having at least one first hole formed through the inner circumferential surface of the cylinder and an outer circumferential surface of the cylinder to guide refrigerant discharged from the compression space to the bearing surface; and a porous member inserted into the outer circumferential surface of the cylinder and configured to cover the first hole, the porous member having multiple micropores smaller than the first hole.

First claim

What is claimed is:

1. A linear compressor comprising:
a linear motor that comprises a stator and a mover configured to reciprocate with respect to the stator;
a piston coupled to the mover and configured to move based on reciprocation of the mover;
a cylinder that accommodates the piston and that defines a compression space together with the piston, the cylinder defining at least one first hole that extends from an inner circumferential surface of the cylinder to an outer circumferential surface of the cylinder and that is configured to guide refrigerant discharged from the compression space to a bearing surface defined between the inner circumferential surface of the cylinder and an outer surface of the piston;
a porous member located at the outer circumferential surface of the cylinder and configured to cover the at least one first hole, the porous member defining micropores having a diameter smaller than a diameter of the at least one first hole;
a cover member that has a cylindrical shape surrounding the porous member and that is located at an outer circumferential surface of the porous member, the cover member defining a plurality of second holes that are in communication with the micropores of the porous member and extend from an outer circumferential surface of the cover member to an inner circumferential surface of the cover member; and
a frame that surrounds the cover member and is located at the outer circumferential surface of the cover member, the frame defining a bearing communication hole configured to guide the refrigerant discharged from the compression space to the plurality of second holes of the cover member,
wherein the plurality of second holes are arranged in a circumferential direction of the cover member and configured to supply the refrigerant into the at least one first hole through the micropores of the porous member.

2. The linear compressor of claim 1 , wherein a diameter of one of the plurality of second holes is greater than the diameter of the micropores.

3. The linear compressor of claim 1 , further comprising:
a sealing member located at each of a first end of the porous member and a second end of the porous member.

4. The linear compressor of claim 3 , wherein the cover member surrounds the sealing member and is configured to restrict movement of the sealing member.

5. The linear compressor of claim 4 , wherein the cylinder defines an annular recess configured to receive the sealing member and to restrict movement of the sealing member in the annular recess.

6. The linear compressor of claim 1 , wherein the inner circumferential surface of the cover member is in contact with the outer circumferential surface of the porous member, and
wherein the outer circumferential surface of the cover member is in contact with an inner circumferential surface of the frame.

7. The linear compressor of claim 1 , wherein the piston is configured to move between a front side of the cylinder and a rear side of the cylinder opposite to the front side, a volume of the compression space decreasing based on the piston moving from the rear side toward the front side,
wherein the at least one first hole comprises a plurality of first holes, the plurality of first holes comprising a plurality of front holes defined at the front side of the cylinder and a plurality of rear holes defined at the rear side of the cylinder, and
wherein at least one of the plurality of second holes is located at a position between the plurality of first holes.

8. The linear compressor of claim 7 , wherein:
the plurality of front holes are arranged along a lengthwise direction of the cylinder,
the plurality of rear holes are arranged along the lengthwise direction of the cylinder, and
the at least one of the plurality of second holes is located at a position circumferentially between the plurality of front holes and circumferentially between the plurality of rear holes.

9. The linear compressor of claim 8 , wherein the at least one of the plurality of second holes is located at a position spaced apart by a same distance from each hole of the plurality of first holes.

10. A linear compressor comprising:
a casing;
a linear motor located in an inner space of the casing, the linear motor comprising a stator and a mover configured to reciprocate with respect to the stator;
a cylinder that is located inside the linear motor and that defines a compression space, the cylinder defining a first hole that extends from an outer circumferential surface of the cylinder to an inner circumferential surface of the cylinder;
a piston located inside the cylinder and configured to reciprocate relative to the cylinder based on movement of the mover, the piston being configured to compress refrigerant in the compression space;
a discharge valve configured to open and close at least a portion of the compression space;
a discharge cover that accommodates the discharge valve, the discharge cover defining a discharge space configured to receive refrigerant discharged from the compression space;
a frame located in the inner space of the casing and configured to support the cylinder;
a porous filter membrane that is located between the outer circumferential surface of the cylinder and an inner circumferential surface of the frame, the porous filter membrane defining micropores having a diameter smaller than a first diameter of the first hole;
a sealing member located at one of two lengthwise sides of the porous filter membrane; and
a shrink tube that surrounds the porous filter membrane and that is located at an outer circumferential surface of the porous filter membrane, the shrink tube defining a second hole having a second diameter larger than the diameter of the micropores,
wherein the frame defines a refrigerant passage that allows communication between the discharge space and the second hole and that is configured to guide the refrigerant discharged from the compression space to the second hole of the shrink tube.

11. The linear compressor of claim 10 , wherein the first hole comprises a plurality of first holes that are arranged along a lengthwise direction of the cylinder,
wherein the second hole is located between the plurality of first holes in the lengthwise direction of the cylinder, and
wherein the plurality of first holes are arranged about the second hole.

12. The linear compressor of claim 11 , wherein each of the plurality of first holes is located at a position spaced apart by a same distance from the second hole.

13. The linear compressor of claim 10 , wherein the shrink tube surrounds the sealing member.

14. The linear compressor of claim 10 , wherein the outer circumferential surface of the porous filter membrane is in contact with an inner circumferential surface of the shrink tube, and
wherein the inner circumferential surface of the frame is in contact with an outer circumferential surface of the shrink tube.

15. The linear compressor of claim 1 , wherein an end of the bearing communication hole is connected to and in fluid communication with the plurality of second holes of the cover member.

16. The linear compressor of claim 10 , further comprising an additional sealing member located at the other of the two lengthwise sides of the porous filter membrane.

17. The linear compressor of claim 16 , wherein the shrink tube surrounds the sealing member and the additional sealing member.

18. The linear compressor of claim 1 , wherein the plurality of second holes are spaced apart from one another in the circumferential direction of the cover mem

Assignees

• Lg Electronics Inc

Inventors

• Ahn Kwangwoon
• Kim Donghan
• Noh Kiwon
• Park Joonsung

Classifications

• Y10S92/02

  Fluid bearing · CPC title

• F04B39/02

  Lubrication (of machines or engines in general F01M) · CPC title

• F04B39/16 Primary

  Filtration; Moisture separation · CPC title

• F16C33/1005

  with gas, e.g. air, as lubricant · CPC title

• F16C33/105

  Conditioning, e.g. metering, cooling, filtering · CPC title