Scroll compressor

Abstract

A scroll compressor of the present disclosure comprises: a casing; a rotating shaft centered on an axis extending in the vertical direction within the casing; a bearing that supports the rotating shaft and partitions the interior of the casing into upper and lower sections; a compression part that is located above the bearing and includes a movable scroll capable of eccentric rotation about the axis in accordance with rotation of the rotating shaft, and a fixed scroll that meshes with the movable scroll from above to form a compression chamber on the inside; a first oil supply part that supplies lubricating oil stored below the bearing in the casing to a machine chamber partitioned between the bearing and the movable scroll; and a second oil supply part that is provided separately from the first oil supply part and supplies lubricating oil stored below the bearing to an upper space in the casing partitioned by the bearing, by routing the lubricating oil via the exterior of the rotating shaft.

Description

Scroll Compressor

[0001] The present disclosure relates to a scroll compressor. The present application claims priority to Japanese Patent Application No. 2025-038953 filed in Japan on March 12, 2025, the content of which is incorporated herein by reference.

[0002] Patent Document 1 discloses a scroll compressor. The scroll compressor includes a casing, a compression unit, and a seal portion. The casing accommodates a rotating shaft, a driving unit, the compression unit, and a main bearing that supports an upper end of the rotating shaft, and stores lubricating oil therein. The compression unit includes a movable scroll and a fixed scroll. A compression chamber for compressing refrigerant is formed between the movable scroll and the fixed scroll. The seal portion seals fluid flow between the inside and the outside of the compression unit in the casing.

[0003] Further, in the scroll compressor described in Patent Document 2, a first oil supply passage and a second oil supply passage are formed in the rotating shaft. The first oil supply passage guides the lubricating oil stored in the lower oil sump to a space above the rotating shaft, and supplies the lubricating oil to the compression unit and sliding portions around the compression unit. The second oil supply passage extends downward from the space above the rotating shaft separately from the first oil supply passage. Furthermore, an oil supply lateral hole that branches from these oil supply passages and supplies lubricating oil to the sliding portion is provided in an upper portion of the first oil supply passage or the second oil supply passage.

[0004] Japanese Unexamined Patent Publication No. 2020-51406Japanese Unexamined Patent Publication No. 2014-129740

[0005] In the scroll compressor described in Patent Document 1, the seal portion prevents excessive inflow of lubricating oil into the compression unit. However, there is no description regarding the pressing force of the seal portion. For example, when the amount of lubricating oil flowing into the compression unit becomes extremely small, wear progresses in the compression unit and sliding portions around the compression unit, which may lower durability.

[0006] Furthermore, while the scroll compressor described in Patent Document 2 can increase the amount of lubricating oil supplied to the sliding parts, multiple passages for lubrication are formed inside the rotating shaft. As a result, the amount of material removed from the rotating shaft increases, leaving the problem of reduced stability and rigidity of the rotating shaft.

[0007] This disclosure was made to solve the above problems and aims to provide a scroll compressor that enables a stable supply of lubricating oil to the space in which the compression section is housed, and suppresses a decrease in the stability and rigidity of the rotating shaft.

[0008] To solve the above problems, the scroll compressor according to the present disclosure comprises a casing, a rotating shaft extending vertically within the casing and centered on an axis, a bearing that supports the rotating shaft so as to be rotatable around the axis and divides the inside of the casing vertically, a compression section having a movable scroll connected to the rotating shaft above the bearing and capable of eccentrically rotating around the axis as the rotating shaft rotates, and a fixed scroll that meshes with the movable scroll from above to form a compression chamber on the inside and has an intake port for drawing in refrigerant from an intake chamber outside the compression chamber, a first lubrication section that supplies lubricating oil stored below the bearing in the casing to a machine room partitioned between the bearing and the movable scroll, and a second lubrication section provided separately from the first lubrication section that supplies lubricating oil stored below the bearing to the upper space inside the casing partitioned by the bearing via the outside of the rotating shaft.

[0009] The scroll compressor of this disclosure enables a stable supply of lubricating oil to the space in which the compression section is housed, and suppresses a decrease in the stability and rigidity of the rotating shaft.

[0010] This is a configuration diagram of a scroll compressor according to an embodiment of the present disclosure. This is an enlarged view of the area around the compression section according to an embodiment of the present disclosure. This is a schematic diagram of the internal configuration of a lubrication pump according to an embodiment of the present disclosure, viewed from above. This is a configuration diagram of a scroll compressor according to a first modified example of the present disclosure. This is a configuration diagram of a scroll compressor according to a second modified example of the present disclosure.

[0011] (Configuration of the scroll compressor) Hereinafter, a scroll compressor 1 according to an embodiment of the present disclosure will be described with reference to Figures 1 to 3. As shown in Figures 1 and 2, the scroll compressor 1 comprises a casing 2, a rotating shaft 3, a main bearing 4 (bearing), a sub-bearing 5, a drive unit 6, a compression unit 7, a coupling 8, a balance weight 9, a thrust bearing 10, an Oldham ring 11, a seal unit 12, a discharge valve mechanism 13, and a lubrication mechanism 14.

[0012] (Casing) The casing 2 extends vertically. The casing 2 is provided with an intake pipe 15 and a discharge pipe 16. The intake pipe 15 draws refrigerant R from outside the casing 2 into the upper space above the main bearing 4, which will be described later, inside the casing 2. The intake pipe 15 is located at the top of the casing 2. The intake pipe 15 is located opposite the compression section 7 in a direction perpendicular to the axis O1. The discharge pipe 16 discharges the refrigerant R, which has become high-pressure after being compressed by the compression section 7. The discharge pipe 16 is located at the top of the casing 2, above the intake pipe 15. Lubricating oil L (refrigerant oil) is stored at the bottom of the casing 2.

[0013] (Rotation Axis) The rotation axis 3 is located inside the casing 2. The rotation axis 3 is formed in a cylindrical shape with axis O1 as its center. In this embodiment, axis O1 extends in the vertical direction. Hereinafter, the direction in which axis O1 of the rotation axis 3 extends will be referred to as the "axial direction".

[0014] The rotating shaft 3 is supported within the casing 2 so as to be rotatable around the axis O1 by a main bearing 4 and a sub-bearing 5, which will be described later. An eccentric shaft 3a is provided at the upper end of the rotating shaft 3. The eccentric shaft 3a is provided at an offset (eccentric) position with respect to the axis O1. The eccentric shaft 3a is formed in a columnar shape with an eccentric axis O2, which is different from the axis O1, as its center. The eccentric axis O2 extends parallel to the axis O1. When the rotating shaft 3 is rotating around the axis O1, the eccentric shaft 3a revolves around the axis O1 of the rotating shaft 3.

[0015] (Main Bearing) The main bearing 4 supports the upper end of the rotating shaft 3 so that it can rotate around the axis O1. The outer surface of the main bearing 4 is fixed by welding or interference fit, etc., in contact with the inner surface of the casing 2 over its entire circumference. The main bearing 4 divides the space inside the casing 2 into upper and lower sections. The lower space inside the casing 2 below the main bearing 4 is the drive chamber V1 which houses the drive unit 6. The upper space inside the casing 2 above the main bearing 4 houses the compression unit 7. This upper space is divided into the machine chamber V2, which will be described later, the intake chamber V3, and the discharge chamber V4.

[0016] The main bearing 4 comprises a bearing lower part 4a, a bearing end plate 4b, and a bearing outer cylinder portion 4c. The bearing lower part 4a is provided to cover the upper end of the rotating shaft 3 from the outer circumference. The bearing end plate 4b is provided above the bearing lower part 4a and is formed in a disc shape that extends horizontally. A balance weight chamber 4d is formed in the center of the bearing end plate 4b. The balance weight chamber 4d houses a balance weight 9 that is attached to the eccentric shaft 3a. The bearing outer cylinder portion 4c is formed to rise upward along the entire circumference of the outer edge of the bearing end plate 4b. The outer circumferential surface of the bearing end plate 4b and the outer circumferential surface of the bearing outer cylinder portion 4c are fixed to the inner circumferential surface of the casing 2.

[0017] Furthermore, a machine chamber V2 is formed between the main bearing 4 and the movable scroll 20, which will be described later. The machine chamber V2 is partitioned not only by the main bearing 4 and the movable scroll 20, but also by the fixed scroll 21, which will be described later. The machine chamber V2 houses movable members such as the eccentric shaft 3a, the coupling 8, balance weight 9, thrust bearing 10, and Oldham ring 11, which will be described later. When the compression section 7 is driven, the lubricating oil L stored in the drive chamber V1 is guided to the machine chamber V2 by the lubrication mechanism 14, which will be described later. In addition, a through hole 4e is formed on the outer peripheral edge of the bearing end plate 4b, inside the bearing outer cylinder 4c. The through hole 4e penetrates the bearing end plate 4b in the axial direction. The through hole 4e returns the lubricating oil L supplied to the machine chamber V2 back to the drive chamber V1. In addition, a keyway 4f is formed on the upper surface of the bearing end plate 4b, into which the Oldham ring 11 is slidably engaged.

[0018] (Sub-bearing) The sub-bearing 5 rotatably supports the lower end of the rotating shaft 3. The sub-bearing 5 is fixed to the inner circumferential surface of the casing 2.

[0019] (Drive Unit) The drive unit 6 is an electric motor located in the drive chamber V1 inside the casing 2. The drive unit 6 rotates the rotating shaft 3.

[0020] (Compression section) The compression section 7 is connected to the drive section 6 by a rotating shaft 3. The compression section 7 compresses the refrigerant R by being driven by the rotation of the rotating shaft 3. The compression section 7 includes a movable scroll 20, a fixed scroll 21, and a discharge cover 22.

[0021] (Movable Scroll) The movable scroll 20 is connected to the rotating shaft 3 above the main bearing 4. The movable scroll 20 has a movable end plate 20a and a movable lap 20b. The movable end plate 20a is formed in the shape of a disc extending in the horizontal direction. The movable lap 20b protrudes upward from the upper surface of the movable end plate 20a and is formed in the shape of a spiral. A boss 23 is integrally provided on the lower surface of the movable end plate 20a. An eccentric shaft 3a is fitted into the boss 23 via a coupling 8, which will be described later. As a result, when the rotating shaft 3 rotates, the movable scroll 20 revolves around the axis O1 without rotating on its own. In this way, the movable scroll 20 is made capable of eccentric rotation around the axis O1 in conjunction with the rotation of the rotating shaft 3.

[0022] (Fixed Scroll) The fixed scroll 21 is provided to engage with the movable scroll 20 from above. When the fixed scroll 21 and the movable scroll 20 engage, a volume-variable compression chamber V5 is formed inside the fixed scroll 21. The fixed scroll 21 has a fixed end plate 21a, a fixed wrap 21b, and a fixed outer cylinder portion 21c. The fixed end plate 21a is formed in the shape of a disc extending in the horizontal direction. A discharge port 24 is formed in the center of the fixed end plate 21a, penetrating in the axial direction. The discharge port 24 discharges the refrigerant R compressed in the compression chamber V5. The fixed wrap 21b protrudes downward from the lower surface of the fixed end plate 21a and is formed in a spiral shape. The fixed wrap 21b is housed between the movable wraps 20b. The fixed outer cylinder portion 21c is formed to rise downward from the outer peripheral edge of the fixed end plate 21a. The fixed outer cylinder portion 21c surrounds the fixed wrap 21b from the outer circumference. The fixed outer cylinder portion 21c is formed to cover the fixed wrap 21b and the movable wrap 20b from the outer circumference. The fixed outer cylinder portion 21c is fitted into the casing 2 and abuts against the bearing outer cylinder portion 4c of the main bearing 4. The fixed outer cylinder portion 21c is fixed to the bearing outer cylinder portion 4c by bolts 25. An intake chamber V3 is formed on the outer circumference of the fixed outer cylinder portion 21c. That is, the intake chamber V3 is formed outside the compression chamber V5. The intake chamber V3 is partitioned by the fixed scroll 21 and the discharge cover 22, which will be described later. An intake pipe 15 is connected to the intake chamber V3, and refrigerant R is introduced from outside the casing 2 through the intake pipe 15. In addition, an intake port 21d that penetrates radially is formed in the fixed outer cylinder portion 21c. The intake port 21d draws refrigerant R from the intake chamber V3 into the compression chamber V5. The compression chamber V5 moves to the center of the compression section 7, decreasing in volume due to the eccentric movement of the movable scroll 20. As a result, the refrigerant R in the compression chamber V5 is compressed. The refrigerant R compressed in the compression chamber V5 is discharged from the discharge port 24.

[0023] (Discharge Cover) The discharge cover 22 is positioned above the fixed scroll 21. The discharge cover 22 is formed in a horizontally extending disc shape. A discharge port 26 is formed in the center of the discharge cover 22. The discharge cover 22 further divides the upper space above the main bearing 4 within the casing 2 vertically. The space above the discharge cover 22, which is divided by the discharge cover 22, is designated as the discharge chamber V4. An intermediate chamber V6 is also formed between the discharge cover 22 and the fixed scroll 21. Refrigerant R discharged from the compression chamber V5 flows into the intermediate chamber V6 through the discharge port 24. Refrigerant R discharged from the intermediate chamber V6 flows into the discharge chamber V4 through the discharge port 26. The discharge piping 16 described above is connected to the discharge chamber V4. The refrigerant R in the discharge chamber V4 is discharged outside the casing 2 through the discharge piping 16.

[0024] (Coupling) The coupling 8 is a cylindrical member fitted onto the outer surface of the eccentric shaft 3a. The coupling 8 is located within the boss 23 of the movable scroll 20. As the eccentric shaft 3a rotates around the axis O1, the rotational force is transmitted to the movable scroll 20 through the coupling 8. The coupling 8 is also referred to as a drive bush.

[0025] (Balance weight) The balance weight 9 is attached to the eccentric shaft 3a via the coupling 8. The balance weight 9 balances the weight of the movable scroll 20, which is mounted eccentrically with respect to the rotating shaft 3.

[0026] (Thrust bearing) The thrust bearing 10 is provided between the movable end plate 20a of the movable scroll 20 and the bearing end plate 4b of the main bearing 4. The thrust bearing 10 supports the axial load applied to the rotating shaft 3.

[0027] (Oldham ring) The Oldham ring 11 is located between the movable scroll 20 and the bearing end plate 4b of the main bearing 4, and is provided on the outer circumference side of the thrust bearing 10. The Oldham ring 11 restricts the rotation of the movable scroll 20 (rotation around the eccentric axis O2). The Oldham ring 11 has a key 11a that slidably engages with a keyway 4f formed in the main bearing 4.

[0028] (Sealing section) The sealing section 12 is provided between the fixed scroll 21 and the movable scroll 20. The sealing section 12 seals the flow of fluid between the inside (compression chamber V5) and the outside of the compression section 7. The sealing section 12 suppresses the inflow of lubricating oil L into the inside of the compression section 7.

[0029] (Discharge valve mechanism) The discharge valve mechanism 13 prevents backflow of the refrigerant R flowing through the discharge ports 24 and 26. The discharge valve mechanism 13 is provided in both the intermediate chamber V6 and the discharge chamber V4. The discharge valve mechanism 13 in the intermediate chamber V6 is attached to the upper surface of the fixed end plate 21a of the fixed scroll 21. The discharge valve mechanism 13 in the discharge chamber V4 is attached to the upper surface of the discharge cover 22.

[0030] (Lubrication Mechanism) The lubrication mechanism 14 supplies lubricating oil L stored at the bottom of the casing 2 to the sliding parts in the space above the main bearing 4. The sliding parts refer to the sliding parts in the machine chamber V2 and the compression chamber V5. The sliding parts include, for example, the sliding parts between the main bearing 4 and the rotating shaft 3, the sliding parts between the eccentric shaft 3a, the balance weight 9, the boss 23, the balance weight chamber 4d, the sliding parts between the Oldham ring 11 and the keyway 4f, and the sliding parts between the movable scroll 20 and the fixed scroll 21. The lubrication mechanism 14 comprises a lubrication pump 30, a first lubrication section 40, and a second lubrication section 50.

[0031] (Oil supply pump) The oil supply pump 30 is attached to the lower end of the rotating shaft 3. The oil supply pump 30 pumps up the lubricating oil L stored at the bottom of the casing 2.

[0032] An example of a lubrication pump 30 will be described with reference to Figure 3. As shown in Figure 3, the lubrication pump 30 has a case 31 and a pump rotor 32. The pump rotor 32 is twinned. The pump rotor 32 has two rotors, an outer rotor 32a and an inner rotor 32b. Therefore, the lubrication pump 30 is capable of handling two separate lubrication oil supply circuits L.

[0033] The case portion 31 has a cylinder 31a that covers the lower end of the rotating shaft 3 from the outer circumference. An outer rotor 32a and an inner rotor 32b are housed on the inner circumference side of the cylinder 31a. The outer rotor 32a and the inner rotor 32b are each formed in an annular shape. The inner rotor 32b is provided on the inner circumference side of the outer rotor 32a. The outer rotor 32a and the inner rotor 32b are each provided so as to be able to rotate eccentrically around the axis O1 as the rotating shaft 3 rotates. A first pressurizing chamber 33a is formed between the outer circumference surface of the outer rotor 32a and the inner circumference surface of the cylinder 31a. A second pressurizing chamber 33b is formed between the outer circumference surface of the inner rotor 32b and the inner circumference surface of the outer rotor 32a.

[0034] Furthermore, the case portion 31 is provided with a first inlet 34a, a first discharge port 34b, a second inlet 34c, a second discharge port 34d, and a third discharge port 34e. The first inlet 34a draws in lubricating oil L stored in the lower part of the casing 2 and guides it to the first pressurizing chamber 33a. The volume of the first pressurizing chamber 33a is variable due to the eccentric movement of the outer rotor 32a. When the volume of the first pressurizing chamber 33a increases, lubricating oil L is drawn into the first pressurizing chamber 33a from the bottom of the casing 2 through the first inlet 34a. Subsequently, as the volume of the first pressurizing chamber 33a decreases, the lubricating oil L inside the first pressurizing chamber 33a is pressurized. The first discharge port 34b discharges the pressurized lubricating oil L in the first pressurizing chamber 33a to the second lubrication path 51, which will be described later. The second inlet 34c is in communication with the first inlet 34a. The second intake port 34c draws in lubricating oil L stored in the lower part of the casing 2 from the first intake port 34a and guides it to the second pressurizing chamber 33b. The volume of the second pressurizing chamber 33b is variable due to the eccentric movement of the inner rotor 32b. When the volume of the second pressurizing chamber 33b increases, lubricating oil L is drawn into the second pressurizing chamber 33b from the communication point with the first intake port 34a through the second intake port 34c. Subsequently, as the volume of the second pressurizing chamber 33b decreases, the lubricating oil L in the second pressurizing chamber 33b is pressurized. The second discharge port 34d discharges the lubricating oil L pressurized in the second pressurizing chamber 33b to the third discharge port 34e. The third discharge port 34e discharges the lubricating oil L to the first lubrication path 41, which will be described later.

[0035] (First Lubrication Unit) As shown in Figure 1, the first lubrication unit 40 supplies lubricating oil L stored below the main bearing 4 in the casing 2 to the machine room V2. The first lubrication unit 40 has a first lubrication path 41 formed inside the rotating shaft 3. The first lubrication path 41 extends upward from the lubrication pump 30 along the axis O1. The first lubrication path 41 guides the lubricating oil L pumped up by the lubrication pump 30 to the balance weight chamber 4d of the machine room V2.

[0036] (Second lubrication section) The second lubrication section 50 is provided separately from the first lubrication section 40. The second lubrication section 50 supplies lubricating oil L stored below the bearing to the upper space within the casing 2 partitioned by the main bearing 4, via the outside of the rotating shaft 3. In this embodiment, the second lubrication section 50 supplies lubricating oil L to the balance weight chamber 4d. The second lubrication section 50 has a second lubrication path 51, a branch path 52, and a valve 53.

[0037] (Second lubrication route) The second lubrication route 51 is provided to pass through the outside of the casing 2. The second lubrication route 51 guides the lubricating oil L stored below the bearing to the upper space formed above the main bearing 4 within the casing 2. The second lubrication route 51 has a first connection route 51a, an external route 51b, and a second connection route 51c. The first connection route 51a connects the lubrication pump 30 to the lower end of the external route 51b. The external route 51b is located outside the casing 2. The external route 51b extends in the axial direction. Lubricating oil L, pumped up by the lubrication pump 30 and pressurized, is supplied to the external route 51b through the first connection route 51a. The second connection route 51c connects the upper end of the external route 51b to the upper part of the scroll compressor 1 with respect to the main bearing 4. The second connection path 51c guides the lubricating oil L that has passed through the external path 51b into the upper space within the casing 2, which is partitioned by the main bearing 4.

[0038] In this embodiment, the second connection path 51c connects the upper end of the external path 51b to the balance weight chamber 4d. That is, the second lubrication path 51 guides lubricating oil L to the balance weight chamber 4d of the machine chamber V2.

[0039] (Branching route) The branching route 52 guides the lubricating oil L flowing through the external route 51b to the lower space (drive chamber V1) within the casing 2, which is partitioned by the main bearing 4. The branching route 52 extends horizontally from the external route 51b to the portion of the casing 2 below the drive unit 6.

[0040] (Valve) Valve 53 is a solenoid valve that is capable of opening and closing the branch path 52. Valve 53 is located outside the casing 2.

[0041] (Effects) According to the present embodiment, the following effects are achieved.

[0042] A conventional oil supply pump is driven by a rotational driving force transmitted from a rotating shaft, and pumps out the lubricating oil stored at the bottom of a casing to supply it to a machine room. For this reason, there has been a concern that the supply amount of lubricating oil to the machine room decreases during low-speed operation compared with during high-speed operation.

[0043] In contrast, in the present embodiment, a scroll compressor 1 includes a first oil supply portion 40 and a second oil supply portion 50. The first oil supply portion 40 supplies the lubricating oil L stored below a main bearing 4 in a casing 2 to a machine room V2 defined between the main bearing 4 and a movable scroll 20. The second oil supply portion 50 is provided separately from the first oil supply portion 40. The second oil supply portion 50 supplies the lubricating oil L stored below the main bearing 4 to an upper space in the casing 2 defined by the main bearing 4 via the outside of a rotating shaft 3.

[0044] Thereby, the lubricating oil L stored in the lower part of the casing 2 is supplied via the first oil supply portion 40 and the second oil supply portion 50 to the upper space in the casing 2, which accommodates a compression portion 7 defined by the main bearing 4. Therefore, regardless of the rotation speed of the rotating shaft 3, it is possible to stably supply the lubricating oil L to the space accommodating the compression portion 7 including the machine room V2. Therefore, wear of the seal portion 12 and seizure on the wrap surface of the movable scroll 20 can be prevented. In addition, since the second oil supply portion 50 supplies the lubricating oil L to the upper space via the outside of the rotating shaft 3, hollowing inside the rotating shaft 3 is reduced, and the reduction in stability and rigidity of the rotating shaft 3 is suppressed.

[0045] In addition, in the present embodiment, the second oil supply portion 50 supplies the lubricating oil L to a balance weight chamber 4d. Thereby, the oil supply amount to the balance weight chamber 4d is increased, and stable supply of the lubricating oil L to the sliding portion around the balance weight chamber 4d is enabled. Therefore, the durability and reliability of the main bearing 4 are improved. In addition, since the main bearing 4 is easier to process than other members, the processing for providing the second oil supply portion 50 can be easily performed.

[0046] Furthermore, in the present embodiment, the second oil supply unit 50 includes a second oil supply path 51. The second oil supply path 51 is provided so as to pass through the outside of the casing 2. The second oil supply path 51 guides the lubricating oil L stored below the bearing to the upper space. This allows the second oil supply path 51 to be installed outside the casing 2 where work is easy. Therefore, the degree of freedom in installing the second oil supply unit 50 can be improved, and manufacturing efficiency can be enhanced.

[0047] By the way, simply providing the second oil supply unit 50 may cause an excessive supply of the lubricating oil L through the second oil supply path 51 during high-speed operation, which raises a concern that oil rising will be accelerated. In response to this, in the present embodiment, the second oil supply unit 50 includes a branch path 52 and a valve 53. The branch path 52 branches from an external path 51b arranged outside the casing 2 in the second oil supply path 51. The branch path 52 guides the lubricating oil L flowing in the external path 51b to the lower space inside the casing 2 defined and formed by the main bearing 4. The valve 53 is provided so as to be able to open and close the branch path 52. Thus, by opening the valve 53, at least part of the lubricating oil L flowing through the second oil supply path 51 can be returned to the lower space inside the casing 2. Therefore, the supply amount of the lubricating oil L by the second oil supply unit 50 can be adjusted. For example, during low-speed operation, the valve 53 is closed to supply the lubricating oil L from both the first oil supply unit 40 and the second oil supply unit 50 to above the main bearing 4, whereas during high-speed operation, the valve 53 is opened to reduce the oil supply amount of the second oil supply unit 50, so that oil can be supplied mainly through the first oil supply unit 40. During high-speed operation, the valve 53 may be fully opened so that oil is supplied only by the first oil supply unit 40. Therefore, excessive supply of the lubricating oil L through the second oil supply path 51 during high-speed operation can be suppressed. Accordingly, more stable supply of the lubricating oil L can be achieved.

[0048] In the present embodiment, the valve 53 for opening and closing the branch path 52 is provided outside the casing 2. This makes the valve 53 easy to operate, and facilitates adjustment of the supply amount of the lubricating oil L by the second oil supply unit 50.

[0049] (First Modification) Next, the first modification will be described with reference to Figure 4. As shown in Figure 4, in this modification, the second connection path 51c connects the upper end of the external path 51b to the keyway 4f. Therefore, the second lubrication unit 50 is able to supply lubricating oil L to the keyway 4f.

[0050] According to this modified example, the amount of lubricant supplied to the keyway 4f is increased, enabling a stable supply of lubricating oil L to the sliding portion of the Oldham ring 11. Therefore, wear on the Oldham ring 11 can be prevented, thereby improving the durability and reliability of the Oldham ring 11.

[0051] (Second Modification) Next, a second modification will be described with reference to Figure 5. As shown in Figure 5, in this modification, the second connection path 51c connects the upper end of the external path 51b to the suction pipe 15. Therefore, the second lubrication unit 50 is able to supply lubricating oil L to the suction pipe 15.

[0052] According to this modified configuration, lubricating oil L can be directly supplied into the suction pipe 15. The lubricating oil L supplied into the suction pipe 15 is then guided to the compression section 7. This allows for a direct supply of lubricating oil L to the compression section 7. Therefore, a stable supply of lubricating oil L to the sliding portion between the movable scroll 20 and the fixed scroll 21 becomes possible.

[0053] In this modified example, the mechanism for adjusting the amount of fuel supplied by the second fuel supply unit 50 (branching path 52 and valve 53) does not need to be provided.

[0054] (Other Embodiments) Although embodiments of the present disclosure have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments and may include design changes and the like that do not depart from the gist of the present disclosure.

[0055] In the above embodiment, the case in which the pump rotor 32 of the fuel supply pump 30 has two rotors, an outer rotor 32a and an inner rotor 32b, was described, but it is not limited to this. The fuel supply pump 30 can be selected as appropriate.

[0056] In the above embodiment, the case in which the second lubrication unit 50 supplies lubricating oil L to only one of the balance weight chamber 4d, keyway 4f, and suction pipe 15 was described, but it is not limited to this. The second lubrication unit 50 may supply lubricating oil L to two of the three supply destinations of the balance weight chamber 4d, keyway 4f, and suction pipe 15. Alternatively, the second lubrication unit 50 may supply lubricating oil L to all three supply destinations of the balance weight chamber 4d, keyway 4f, and suction pipe 15.

[0057] <Note> The scroll compressor 1 described in each embodiment can be understood, for example, as follows.

[0058] (1) The scroll compressor 1 according to the first embodiment comprises a casing 2, a rotating shaft 3 centered on an axis O1 extending vertically within the casing 2, a bearing that supports the rotating shaft 3 so as to be rotatable around the axis O1 and divides the inside of the casing 2 vertically, a movable scroll 20 connected to the rotating shaft 3 above the bearing and capable of eccentrically rotating around the axis O1 as the rotating shaft 3 rotates, and a compression chamber V5 formed on the inside by meshing with the movable scroll 20 from above, and The device comprises a compression unit 7 having a fixed scroll 21 with an intake port 21d formed therein for drawing in refrigerant R from an intake chamber V3 outside the compression chamber V5; a first lubrication unit 40 that supplies lubricating oil L stored below the bearing in the casing 2 to a machine chamber V2 partitioned between the bearing and the movable scroll 20; and a second lubrication unit 50 provided separately from the first lubrication unit 40 that supplies lubricating oil L stored below the bearing to the upper space within the casing 2 partitioned by the bearing via the outside of the rotating shaft 3. Examples of the upper space include, for example, the machine chamber V2 and intake chamber V3 in the above-described embodiment. An example of the lower space is, for example, the drive chamber V1 in which the drive unit 6 is housed in the above-described embodiment. An example of the bearing is, for example, the main bearing 4 in the above-described embodiment.

[0059] As a result, the lubricating oil L stored in the lower part of the casing 2 is supplied through the first lubrication section 40 and the second lubrication section 50 to the upper space within the casing 2, which is partitioned by the bearing and houses the compression section 7. Therefore, a stable supply of lubricating oil L to the space housing the compression section 7 becomes possible. In addition, since the second lubrication section 50 supplies the lubricating oil L to the upper space via the outside of the rotating shaft 3, the amount of material removed from the inside of the rotating shaft 3 is reduced, and the decrease in the stability and rigidity of the rotating shaft 3 is suppressed.

[0060] (2) The scroll compressor 1 of the second embodiment is the scroll compressor 1 of (1), wherein the second lubrication unit 50 is provided so as to pass outside the casing 2 and has a second lubrication path 51 that guides lubricating oil L stored below the bearing into the upper space.

[0061] This allows the second lubrication route 51 to be installed outside the casing 2, which is easier to work with. Therefore, the degree of freedom in installing the second lubrication unit 50 is improved, and the machinability is also improved.

[0062] (3) The scroll compressor 1 of the third embodiment is the scroll compressor 1 of (2), wherein the second lubrication section 50 may have a branch path 52 that branches off from the external path 51b located outside the casing 2 in the second lubrication path 51 and guides the lubricating oil L flowing in the external path 51b into the lower space inside the casing 2 which is partitioned by the bearing, and a valve 53 that is provided to open and close the branch path 52.

[0063] This allows at least a portion of the lubricating oil L flowing through the second lubrication passage 51 to be returned to the lower space inside the casing 2 by opening the valve 53. Therefore, the amount of lubricating oil L supplied by the second lubrication section 50 can be adjusted.

[0064] (4) The scroll compressor 1 of the fourth embodiment is any one of the scroll compressors 1 of (1) to (3), wherein the second lubrication unit 50 may supply lubricating oil L to a balance weight chamber 4d which houses a balance weight 9 that balances the weight of the movable scroll 20 which is mounted eccentrically with respect to the rotating shaft 3.

[0065] This allows for an increase in the amount of lubrication supplied to the balance weight chamber 4d. Furthermore, it facilitates the processing required to install the second lubrication section 50.

[0066] (5) The scroll compressor 1 of the fifth embodiment is any one of the scroll compressors 1 of (1) to (3), wherein the second lubrication unit 50 may supply lubricating oil L to a keyway 4f formed in the bearing, in which an Oldham ring 11 that restricts the rotation of the movable scroll 20 is slidably engaged.

[0067] This allows for an increase in the amount of lubrication supplied to the keyway 4f. Therefore, wear on the Oldham ring 11 can be prevented.

[0068] (6) The scroll compressor 1 of the sixth embodiment is any one of the scroll compressors 1 of (1) to (3), wherein the second lubrication unit 50 may supply lubricating oil L to a suction pipe 15 that draws refrigerant R into the upper space inside the casing 2 from outside the casing 2.

[0069] This allows lubricating oil L to be directly supplied to the compression section 7. Therefore, a stable supply of lubricating oil L to the sliding portion between the movable scroll 20 and the fixed scroll 21 becomes possible.

[0070] The scroll compressor of this disclosure enables a stable supply of lubricating oil to the space in which the compression section is housed, and suppresses a decrease in the stability and rigidity of the rotating shaft.

[0071] 1 Scroll compressor 2 Casing 3 Rotating shaft 3a Eccentric shaft 4 Main bearing 4a Lower part of bearing 4b Bearing end plate 4c Bearing outer cylinder 4d Balance weight chamber 4e Through hole 4f Keyway 5 Sub bearing 6 Drive unit 7 Compression unit 8 Coupling 9 Balance weight 10 Thrust bearing 11 Oldham ring 11a Key 12 Seal unit 13 Discharge valve mechanism 14 Lubrication mechanism 15 Intake piping 16 Discharge piping 20 Movable scroll 20a Movable end plate 20b Movable lap 21 Fixed scroll 21a Fixed end plate 21b Fixed lap 21c Fixed outer cylinder 21d Intake port 22 Discharge cover 23 Boss 24 Discharge port 25 Bolt 26 Discharge port 30 Lubrication pump 31 Case unit 31a Cylinder 32 Pump rotor 32a Outer rotor 32b Inner rotor 33a First pressurizing chamber 33b Second pressurizing chamber 34a First inlet 34b First discharge port 34c Second inlet 34d Second discharge port 34e Third discharge port 40 First lubrication section 41 First lubrication route 50 Second lubrication section 51 Second lubrication route 51a First connection route 51b External route 51c Second connection route 52 Branch route 53 Valve L Lubricating oil O1 Axis O2 Eccentric axis R Refrigerant V1 Drive chamber V2 Machine chamber V3 Inlet chamber V4 Discharge chamber V5 Compression chamber V6 Intermediate chamber

Claims

1. A scroll compressor comprising: a casing; a rotating shaft centered on an axis extending vertically within the casing; a bearing that supports the rotating shaft so as to be rotatable around the axis and divides the inside of the casing vertically; a compression section having a movable scroll connected to the rotating shaft above the bearing and capable of eccentrically rotating around the axis as the rotating shaft rotates, and a fixed scroll that meshes with the movable scroll from above to form a compression chamber on its inside and has an intake port for drawing in refrigerant from an intake chamber outside the compression chamber; a first lubrication section that supplies lubricating oil stored below the bearing within the casing to a machine chamber partitioned between the bearing and the movable scroll; and a second lubrication section provided separately from the first lubrication section that supplies lubricating oil stored below the bearing to the upper space inside the casing partitioned by the bearing via the outside of the rotating shaft.

2. The scroll compressor according to claim 1, wherein the second lubrication section is provided so as to pass outside the casing and has a second lubrication path that guides lubricating oil stored below the bearing into the upper space.

3. The scroll compressor according to claim 2, wherein the second lubrication section comprises a branch path that branches off from an external path located outside the casing in the second lubrication path and guides lubricating oil flowing through the external path to a lower space within the casing partitioned by the bearing, and a valve provided to open and close the branch path.

4. The scroll compressor according to any one of claims 1 to 3, wherein the second lubrication unit supplies lubricating oil to a balance weight chamber that houses a balance weight that balances the weight of the movable scroll, which is mounted eccentrically with respect to the rotating shaft.

5. The scroll compressor according to any one of claims 1 to 3, wherein the second lubrication section supplies lubricating oil to a keyway formed in the bearing, into which an Oldham ring that restricts the rotation of the movable scroll is slidably engaged.

6. The scroll compressor according to any one of claims 1 to 3, wherein the second lubrication unit supplies lubricating oil from outside the casing to an intake pipe that draws refrigerant into the upper space inside the casing.

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