JP7636428B2 - Compressor and refrigeration cycle device - Google Patents

Description

The present invention relates to a compressor and a refrigeration cycle device.

A rotary compressor is known that includes a compressor housing having a vertically-placed cylindrical sealed container in which lubricating oil is stored, a compression mechanism disposed in the lower part of the sealed container, a motor disposed in the upper part of the sealed container as an electric motor section that drives the compression mechanism, and a rotating shaft. The rotating shaft is provided along a center line that extends vertically through the compressor housing. The compression mechanism is connected to the motor via the rotating shaft.

The compression mechanism comprises an annular cylinder, an upper end plate that closes the upper side of the cylinder, a lower end plate that closes the lower side of the cylinder, a main bearing provided on the upper end plate, and an auxiliary bearing provided on the lower end plate. The compression mechanism also comprises an annular piston that is fitted into the eccentric portion of the rotating shaft and revolves along the inner circumferential surface of the cylinder. The piston is disposed in a cylinder chamber within the cylinder. The main shaft portion of the rotating shaft is rotatably supported by the main bearing, and the auxiliary shaft portion of the rotating shaft is rotatably supported by the auxiliary bearing.

A spiral oil supply groove is provided on the inner peripheral surface of the shaft hole of the auxiliary bearing to supply lubricating oil from the lower end to the upper end of the shaft hole. The oil supply groove is inclined with respect to the rotational direction of the rotating shaft and extends from the lower end to the upper end in the rotational direction of the rotating shaft.

In conventional rotary compressors, the rotation of the rotating shaft draws up the lubricating oil stored in the compressor housing along an oil supply groove that extends from the lower end to the upper end of the shaft hole of the auxiliary bearing. The drawn-up lubricating oil lubricates the sliding parts between the rotating shaft and the auxiliary bearing.

JP 2019-183768 A

A multi-cylinder rotary compressor is known that includes a main muffler that covers the main bearing and a sub-muffler that covers the sub-bearing. Such a multi-cylinder rotary compressor includes a first cylinder that discharges refrigerant compressed in a first cylinder chamber into the main muffler, and a second cylinder that discharges refrigerant compressed in a second cylinder chamber into the sub-muffler. The sub-muffler covers the lower end of the shaft hole of the sub-bearing. The lower end of the shaft hole of the sub-bearing is not submerged in the lubricating oil stored in the compressor housing.

In addition, a balancer is provided on the protruding portion of the rotating shaft that protrudes from the secondary bearing to adjust the imbalance of the rotating body. This balancer is located in the space defined by the secondary bearing and the secondary muffler attached to the secondary bearing.

The lubricating oil that is sucked up moves downwards due to gravity. As a result, the lubricating oil can flow through gaps between the parts into the space defined by the sub-bearing and sub-muffler. However, a balancer attached to the rotating shaft is located in this space. If the lubricating oil accumulates in this space, it can become a resistance to the balancer. An increase in the resistance of the balancer is undesirable in terms of improving the performance and reliability of the compressor.

Therefore, the present invention aims to provide a compressor and a refrigeration cycle device that can reduce the amount of lubricating oil supplied to the space partitioned by the auxiliary bearing and the auxiliary muffler attached to the auxiliary bearing, thereby improving performance and reliability.

In order to solve the above-mentioned problems, a compressor according to an embodiment of the present invention includes a cylindrical sealed container having a center line extending in a vertical direction, a compression mechanism housed in the sealed container and compressing a refrigerant introduced into the sealed container, an electric motor having a cylindrical stator fixed to an inner surface of the sealed container and a rotor disposed inside the stator to generate a rotational driving force for the compression mechanism, and an oil supply mechanism that supplies lubricating oil stored in the sealed container to the compression mechanism, and the compression mechanism is integral with the rotor and rotates below the rotor. a rotating shaft extending toward the eccentric portion and having an eccentric portion, a roller fitted to the eccentric portion and having a lower surface located lower than a lower surface of the eccentric portion, a sub-bearing rotatably supporting a lower end of the rotating shaft, a cylinder having a cylinder chamber that is closed by the sub-bearing and that houses the eccentric portion and the roller, a sub-muffler that covers the sub-bearing and separates a space into which a refrigerant compressed in the cylinder is discharged, and a balancer that is provided on a protruding portion of the rotating shaft protruding from the sub-bearing and that is housed in the sub-muffler. a storage space for storing the lubricating oil guided by the oil supply mechanism and supplied to the compression mechanism is formed at a position surrounded by a lower surface of the eccentric portion, an inner circumferential surface of the roller, and an upper surface of the sub-bearing, the sub-bearing has a through passage formed penetrating the sub-bearing and communicating the storage space with the inside of the sealed container, the through passage having a first opening disposed on a side surface of the sub-bearing and opening into the sealed container, and a second opening disposed on an upper surface of the sub-bearing and opening into the storage space, penetrating the sub-bearing in an L-shape, The rotating shaft has an oil supply hole that supplies lubricating oil guided to the compression mechanism by the oil supply mechanism into a gap with the auxiliary bearing, and an oil supply groove that is provided on the outer peripheral surface of a portion supported by the auxiliary bearing and extends toward the cylinder chamber to reach the cylinder, the auxiliary bearing has a recessed step portion provided on an upper surface of the auxiliary bearing and leading to the storage space, the through passage connects the step portion to the inside of the sealed container, the step portion is dish-shaped and is located inside the rotational locus described by the roller as the rotating shaft rotates.

It is preferable that the auxiliary bearing of the compressor according to the embodiment of the present invention has a recessed step portion provided on the upper surface of the auxiliary bearing and leading to the storage space, and that the through passage connects the step portion to the inside of the sealed container.

The auxiliary bearing of the compressor according to an embodiment of the present invention has a ring-shaped groove portion that is larger in diameter than the portion supporting the rotating shaft, opens toward the upper side of the auxiliary bearing, and leads to the storage space, and it is preferable that the through passage connects the ring-shaped groove portion to the inside of the sealed container.

In addition, the refrigeration cycle device of an embodiment of the present invention includes the compressor, a radiator, an expansion device, a heat absorber, and refrigerant piping that connects the compressor, the radiator, the expansion device, and the heat absorber and allows the refrigerant to circulate.

The present invention provides a compressor and a refrigeration cycle device that can reduce the amount of lubricating oil supplied to the space partitioned by the auxiliary bearing and the auxiliary muffler attached to the auxiliary bearing, thereby improving performance and reliability.

1 is a schematic diagram of a refrigeration cycle device and a compressor according to an embodiment of the present invention. FIG. 2 is an enlarged vertical cross-sectional view of the compressor according to the first embodiment of the present invention. FIG. 2 is a vertical cross-sectional view of a sub-bearing of the compressor according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view of a sub-bearing of the compressor according to the first embodiment of the present invention. FIG. 2 is an enlarged vertical cross-sectional view of the compressor according to the first embodiment of the present invention. FIG. 6 is a longitudinal sectional view of a sub-bearing of a compressor according to a second embodiment of the present invention.

An embodiment of a compressor and a refrigeration cycle device according to the present invention will be described with reference to Figures 1 to 6. Note that in multiple drawings, the same or corresponding components are given the same reference numerals.

First Embodiment
FIG. 1 is a schematic diagram of a refrigeration cycle device and a compressor according to a first embodiment of the present invention.

As shown in FIG. 1, the refrigeration cycle device 1 according to this embodiment is, for example, an air conditioner. The refrigeration cycle device 1 includes a hermetically sealed rotary compressor 2 (hereinafter simply referred to as "compressor 2"), a radiator 3, an expansion device 5, a heat absorber 6, an accumulator 7, and a refrigerant pipe 8. The refrigerant pipe 8 sequentially connects the compressor 2, the radiator 3, the expansion device 5, the heat absorber 6, and the accumulator 7 to allow the refrigerant to flow. The radiator 3 is also called a condenser. The heat absorber 6 is also called an evaporator.

The compressor 2 draws in the refrigerant that has passed through the heat absorber 6 through the refrigerant piping 8, compresses it, and discharges the high-temperature, high-pressure refrigerant through the refrigerant piping 8 to the radiator 3.

The compressor 2 comprises a cylindrical sealed container 11 that is placed vertically, an open-winding type electric motor section 12 (hereinafter simply referred to as the "electric motor section 12") that is housed in the upper half of the sealed container 11, a compression mechanism section 13 that is housed in the lower half of the sealed container 11, a rotating shaft 15 that transmits the rotational driving force of the electric motor section 12 to the compression mechanism section 13, a main bearing 16 that rotatably supports the rotating shaft 15, an auxiliary bearing 17 that rotatably supports the rotating shaft 15 in cooperation with the main bearing 16, and an oil supply mechanism section 22 that supplies lubricating oil 21 (refrigeration oil) stored in the sealed container 11 to the compression mechanism section 13.

The center line of the sealed container 11, which is placed vertically, extends in the vertical direction. The sealed container 11 includes a cylindrical body 11a extending in the vertical direction, a mirror plate 11b that closes the upper end of the body, and a mirror plate 11c that closes the lower end of the body.

A discharge pipe 8a that discharges the refrigerant outside the sealed container 11 is connected to the upper mirror plate 11b of the sealed container 11. The discharge pipe 8a is connected to the refrigerant piping 8. In addition, a pair of sealed terminals 25, 26 that guide the power supplied to the motor unit 12 from the outside to the inside of the sealed container 11 and a pair of terminal blocks 27, 28 are provided on the upper mirror plate 11b of the sealed container 11. Each of the terminal blocks 27, 28 is provided on each of the sealed terminals 25, 26. A plurality of power lines 29 that are electrically connected to the respective sealed terminals 25, 26 and supply power are fixed to each of the terminal blocks 27, 28. The power lines 29 are so-called lead wires.

The electric motor unit 12 generates a driving force that rotates the compression mechanism unit 13. The electric motor unit 12 is disposed above the compression mechanism unit 13. The electric motor unit 12 includes a cylindrical stator 31 fixed to the inner surface of the sealed container 11, a rotor 32 disposed inside the stator 31 and generating a rotational driving force for the compression mechanism unit 13, and a plurality of output wires 33 drawn out from the stator 31 and electrically connected to a pair of sealed terminals 25, 26.

The rotor 32 includes a rotor core 35 having a magnet receiving hole (not shown) and a permanent magnet (not shown) received in the magnet receiving hole. The rotor 32 is fixed to the rotating shaft 15. The rotation center line C of the rotor 32 and the rotating shaft 15 substantially coincides with the center line of the stator 31. The rotation center line C of the rotor 32 and the rotating shaft 15 substantially coincides with the center line of the sealed container 11.

The multiple output wires 33 are power lines that supply power to the stator 31 through the sealed terminals 25, 26, and are so-called lead wires. Multiple output wires 33 are wired depending on the type of the motor unit 12. In this embodiment, six output wires 33 are wired.

In addition, the motor section 12 may be an open winding type or may be an electric motor section having multiple systems, for example, two systems of three-phase windings.

The rotating shaft 15 connects the electric motor unit 12 and the compression mechanism unit 13. The rotating shaft 15 transmits the rotational driving force generated by the electric motor unit 12 to the compression mechanism unit 13. The rotating shaft 15 rotates integrally with the rotor 32 and extends downward from the rotor 32.

The middle portion 15a of the rotating shaft 15 connects the electric motor section 12 and the compression mechanism section 13, and is rotatably supported by the main bearing 16. The lower end portion 15b of the rotating shaft 15 is rotatably supported by the secondary bearing 17. The main bearing 16 and the secondary bearing 17 are also part of the compression mechanism section 13. In other words, the rotating shaft 15 passes through the compression mechanism section 13.

The rotating shaft 15 also has multiple, for example three, eccentric parts 36 between the middle part 15a supported by the main bearing 16 and the lower end part 15b supported by the sub-bearing 17. Each eccentric part 36 is a disk or cylinder having a center that does not coincide with the rotation center line C of the rotating shaft 15.

A balancer 38 is provided on the protruding portion of the rotating shaft 15 that protrudes from the secondary bearing 17.

The compression mechanism 13 compresses the refrigerant introduced into the sealed container 11. When the electric motor 12 rotates the rotating shaft 15, the compression mechanism 13 draws in and compresses the gaseous refrigerant from the refrigerant pipe 8, and discharges the compressed high-temperature, high-pressure refrigerant into the sealed container 11.

The compression mechanism 13 is a rotary type with multiple cylinders, for example, three cylinders. The compression mechanism 13 includes multiple cylinders 42, each having a circular cylinder chamber 41, and multiple annular rollers 43 arranged in each cylinder chamber 41. The compression mechanism 13 may be a rotary type with a single cylinder.

Here, the cylinder 42 closest to the electric motor unit 12 is referred to as the first cylinder 42A, the cylinder 42 farthest from the electric motor unit 12 is referred to as the third cylinder 42C, and the cylinder 42 disposed between the first cylinder 42A and the third cylinder 42C is referred to as the second cylinder 42B.

The compression mechanism 13 includes a main bearing 16 that covers the upper surface of the first cylinder 42A, a first partition plate 45A that covers the lower surface of the first cylinder 42A and the upper surface of the second cylinder 42B, a second partition plate 45B that covers the lower surface of the second cylinder 42B and the upper surface of the third cylinder 42C, and an auxiliary bearing 17 that covers the lower surface of the third cylinder 42C.

In other words, the upper surface of the first cylinder 42A is closed by the main bearing 16. The lower surface of the first cylinder 42A is closed by the first partition plate 45A. The upper surface of the second cylinder 42B is closed by the first partition plate 45A. The lower surface of the second cylinder 42B is closed by the second partition plate 45B. The upper surface of the third cylinder 42C is closed by the second partition plate 45B. The lower surface of the third cylinder 42C is closed by the sub-bearing 17.

That is, the first cylinder 42A is sandwiched between the main bearing 16 and the first partition plate 45A. The second cylinder 42B is sandwiched between the first partition plate 45A and the second partition plate 45B. The third cylinder 42C is sandwiched between the second partition plate 45B and the sub-bearing 17.

The main bearing 16 and the first partition plate 45A are fixed together to the second cylinder 42B by a fastening member 46 such as a bolt. In other words, the main bearing 16 and the first partition plate 45A are fastened together to the second cylinder 42B by the fastening member 46. The main bearing 16 is provided with a first discharge valve mechanism 51A that discharges the refrigerant compressed in the cylinder chamber 41 of the first cylinder 42A, and a first discharge muffler 52 (main muffler) that covers the first discharge valve mechanism 51A. When the pressure difference between the pressure in the cylinder chamber 41 of the first cylinder 42A and the pressure in the first discharge muffler 52 reaches a predetermined value due to the compression action of the compression mechanism 13, the first discharge valve mechanism 51A opens a discharge port (not shown) and discharges the compressed refrigerant into the first discharge muffler 52.

The first discharge muffler 52 separates the space into which the refrigerant compressed in the cylinder 42 is discharged. The first discharge muffler 52 has a discharge hole (not shown) that connects the inside and outside of the first discharge muffler 52. The compressed refrigerant discharged into the first discharge muffler 52 is discharged into the sealed container 11 through the discharge hole.

The second partition plate 45B is provided with a second discharge valve mechanism 51B that discharges the refrigerant compressed in the cylinder chamber 41 of the second cylinder 42B, and a discharge chamber 53. The main bearing 16, the first cylinder 42A, the first partition plate 45A, and the second cylinder 42B have a first hole (not shown) that connects the discharge chamber 53 of the second partition plate 45B to the first discharge muffler 52. When the pressure difference between the pressure in the cylinder chamber 41 of the second cylinder 42B and the pressure in the discharge chamber 53 reaches a predetermined value due to the compression action of the compression mechanism part 13, the second discharge valve mechanism 51B opens a discharge port (not shown) and discharges the compressed refrigerant into the discharge chamber 53. The refrigerant discharged into the discharge chamber 53 is discharged into the first discharge muffler 52 through the first hole. The refrigerant discharged into the first discharge muffler 52 through the first hole merges with the refrigerant compressed in the first cylinder 42A.

The auxiliary bearing 17, the third cylinder 42C, and the second partition plate 45B are fixed together to the second cylinder 42B by fastening members 55 such as bolts. In other words, the auxiliary bearing 17, the third cylinder 42C, and the second partition plate 45B are fastened together to the second cylinder 42B by the fastening members 55. The auxiliary bearing 17 is provided with a third discharge valve mechanism 51C that discharges the refrigerant compressed in the cylinder chamber 41 of the third cylinder 42C, and a second discharge muffler 56 (auxiliary muffler) that covers the third discharge valve mechanism 51C. The second discharge muffler 56 divides the space into which the refrigerant compressed in the third cylinder 42C is discharged. The main bearing 16, the first cylinder 42A, the first partition plate 45A, the second cylinder 42B, the second partition plate 45B, and the third cylinder 42C have a second hole 57 that connects the space in the second discharge muffler 56 to the first discharge muffler 52. When the pressure difference between the pressure in the cylinder chamber 41 of the third cylinder 42C and the pressure in the second discharge muffler 56 reaches a predetermined value due to the compression action of the compression mechanism 13, the third discharge valve mechanism 51C opens a discharge port (not shown) to discharge the compressed refrigerant into the second discharge muffler 56. The refrigerant discharged into the second discharge muffler 56 passes through the second hole 57 and is discharged into the first discharge muffler 52. The refrigerant discharged into the first discharge muffler 52 merges with the refrigerant compressed in the first cylinder 42A and the refrigerant compressed in the second cylinder 42B.

The first hole may be a part of the second hole 57. The discharge chamber 53 of the second partition plate 45B may be connected to the inside of the second discharge muffler 56. In other words, the first hole may be connected to the inside of the second discharge muffler 56.

The first cylinder 42A is fixed to the sealed container 11 at multiple locations by welding, for example, spot welding, with fastening members 59 such as bolts to a frame 58. In other words, the frame 58 supports the rotor 32 of the motor unit 12, the compression mechanism unit 13, and the rotating shaft 15 to the sealed container 11 via the first cylinder 42A. Note that it is preferable that the center of gravity of the rotor 32 of the motor unit 12, the compression mechanism unit 13, and the rotating shaft 15 in the height direction of the sealed container 11 is located within the range of the thickness of the frame 58 (the dimension of the compressor 2 in the height direction).

The balancer 38 is housed in the second discharge muffler 56 that covers the auxiliary bearing 17. The balancer 38 is, for example, a disk having a center line parallel to the direction of the rotation center line C of the rotating shaft 15, or a sector-shaped plate that is centered on the rotation center line C of the rotating shaft 15. The balancer 38 is provided at a position eccentric to the center line of the balancer 38 and has a through hole 38a that passes through the balancer 38. The lower end of the rotating shaft 15 is press-fitted into the through hole 38a of the balancer 38. The amount of eccentricity of the through hole 38a is adjusted so as to reduce the imbalance of the rotating body of the compression mechanism unit 13 during compression operation.

Incidentally, when a balancer is provided at the upper end of the rotating shaft 15 that protrudes above the rotor 32, the distance between the balancer and the bearing (main bearing 16) that supports the rotating shaft 15 depends on the axial dimension of the rotor 32. By providing a balancer 38 at the lower end of the rotating shaft 15 that protrudes from the secondary bearing 17 as in this embodiment, the distance between the balancer 38 and the bearing (secondary bearing 17) that supports the rotating shaft 15 is significantly shortened compared to when a balancer is provided at the upper end of the rotating shaft 15. Therefore, by arranging the balancer 38 as in this embodiment, deflection of the rotating shaft 15 and the rotor 32 is suppressed.

The multiple suction pipes 61 pass through the sealed container 11 and are connected to the cylinder chambers 41 of the respective cylinders 42. Each cylinder 42 has a suction hole that is connected to each suction pipe 61 and reaches the cylinder chamber 41. The first suction pipe 61A is connected to the cylinder chamber 41 of the first cylinder 42A. The second suction pipe 61B is connected to the cylinder chamber 41 of the second cylinder 42B. The third suction pipe 61C is connected to the cylinder chamber 41 of the third cylinder 42C. The number of the multiple suction pipes 61 may be the same as the number of the multiple cylinders 42 as in this embodiment, or may be shared by two cylinders 42 and may be less than the number of the multiple cylinders 42. For example, the second suction pipe 61B may be connected to the second partition plate 45B. The second partition plate 45B is provided with a refrigerant passage (not shown) that is connected to the second partition plate 45B and branches into the cylinder chamber 41 of the second cylinder 42B and the cylinder chamber 41 of the third cylinder 42C, connecting the two cylinder chambers 41.

The lower part of the sealed container 11 is filled with lubricating oil 21. And most of the compression mechanism part 13 is immersed in the lubricating oil 21 in the sealed container 11.

The oil supply mechanism 22 draws up the lubricating oil 21 in the sealed container 11 and supplies it to the sliding parts of the compression mechanism 13. The oil supply mechanism 22 includes a pump 65 that draws up the lubricating oil 21 in the sealed container 11, and an oil passage 66 that sends the lubricating oil 21 drawn up by the pump 65 to the sliding parts of the compression mechanism 13.

Here, the "sliding parts of the compression mechanism part 13" include, for example, the gap between the eccentric part 36 and the roller 43, the gap between the main bearing 16 and the rotating shaft 15, and the gap between the secondary bearing 17 and the rotating shaft 15.

The pump 65 is, for example, a screw pump (Archimedian screw, Archimedes' spiral). The suction port of the screw pump is immersed in the lubricating oil 21 stored in the sealed container 11.

Here, the second discharge muffler 56 has an oil supply mechanism insertion hole 68 that exposes the lower end of the rotating shaft 15 to the outside of the second discharge muffler 56. The lower end of the rotating shaft 15 is immersed in the lubricating oil 21 in the sealed container 11 through the oil supply mechanism insertion hole 68. The rotating shaft 15 also has a pump arrangement hole 69 that opens at the lower end of the rotating shaft 15 and extends toward the upper end of the rotating shaft 15.

The pump 65 is disposed in the pump arrangement hole 69 of the rotating shaft 15 and has a rotor 71 that extends in a spiral shape along the rotation center line C of the rotating shaft 15. The rotor 71 is integrally rotated with the rotating shaft 15. The rotor 71 rotates together with the rotating shaft 15 to continuously pump the lubricating oil 21 from the opening at the lower end of the rotating shaft 15 into the pump arrangement hole 69 of the rotating shaft 15.

In addition, the pump 65 is not limited to the rotor 71, so long as it is provided in the sealed container 11 and can continuously supply the lubricating oil 21 into the pump mounting hole 69 of the rotating shaft 15. The pump 65 may be a turbo pump driven by the rotational driving force of the rotating shaft 15, or may be a volumetric pump. In this case, the pump mounting hole 69 serves as part of the oil passage 66.

The oil passage 66 sends the lubricating oil 21 pumped up to the pump arrangement hole 69 of the rotating shaft 15 by the pump 65 which rotates integrally with the rotating shaft 15 to the sliding parts of the compression mechanism 13 for lubrication.

The oil passage 66 has a first cylinder oil supply hole 73A that supplies the lubricating oil 21 in the pump arrangement hole 69 to the gap between the eccentric portion 36 and the roller 43 housed in the first cylinder 42A, a second cylinder oil supply hole 73B that supplies the lubricating oil 21 in the pump arrangement hole 69 to the gap between the eccentric portion 36 and the roller 43 housed in the second cylinder 42B, and a third cylinder oil supply hole 73C that supplies the lubricating oil 21 in the pump arrangement hole 69 to the gap between the eccentric portion 36 and the roller 43 housed in the third cylinder 42C.

In addition, the oil passage 66 has a main bearing oil supply hole 75A that supplies the lubricating oil 21 in the pump arrangement hole 69 to the gap between the main bearing 16 and the rotating shaft 15, and a secondary bearing oil supply hole 75B that supplies the lubricating oil 21 in the pump arrangement hole 69 to the gap between the secondary bearing 17 and the rotating shaft 15.

The accumulator 7 prevents liquid refrigerant that has not been completely gasified in the heat absorber 6 from being sucked into the compressor 2.

Next, the structure surrounding the rotating shaft 15 and the auxiliary bearing 17 will be described in detail.

Figure 2 is an enlarged vertical cross-sectional view of the compressor according to the first embodiment of the present invention.

Figure 3 is a longitudinal cross-sectional view of a sub-bearing of a compressor according to the first embodiment of the present invention.

Figure 4 is a cross-sectional view of a compressor according to the first embodiment of the present invention.

The rotating shaft 15 rotates counterclockwise in a plan view of the compressor 2. That is, when the rotating shaft 15 rotates, the outer peripheral surface 77 of the rotating shaft 15 depicted in Fig. 2 moves so as to cross the rotation center line C from left to right as indicated by the solid arrow R. Also, when the rotating shaft 15 rotates, the outer peripheral surface 77 of the rotating shaft 15, which faces the inner peripheral surface 78 of the auxiliary bearing 17 depicted in Fig. 3, moves so as to cross the rotation center line C from right to left as indicated by the solid arrow R.

2, the vertical dimension of the eccentric portion 36 of the compressor 2 according to this embodiment is shorter than the vertical dimension of the roller 43. The upper surface of the eccentric portion 36 is located below the upper surface of the roller 43, and the lower surface of the eccentric portion 36 is located above the lower surface of the roller 43. In other words, the eccentric portion 36 is located in the vertical center of the roller 43.

In addition, the underside of roller 43 and the upper surface of secondary bearing 17 are in contact within a range that allows smooth rotational movement of roller 43. Therefore, a gap 90 is present between the underside of eccentric portion 36 and the upper surface of secondary bearing 17. The sides of gap 90 are defined by the inner circumferential surface of roller 43. In other words, gap 90 is surrounded by the underside of eccentric portion 36, the inner circumferential surface of roller 43, and the upper surface of secondary bearing 17.

Hereinafter, a part of the inner peripheral surface of the roller 43 that defines the gap 90 is referred to as the side wall of the gap 90. The inner diameter of the side wall of the gap 90 is larger than the outer diameter of the eccentric portion 36. In addition, the upper half of the side wall of the gap 90 is inclined so as to gradually widen as it goes downward, and the lower half of the side wall of the gap 90 hangs down vertically. Therefore, the lubricating oil 21 supplied to the gap between the eccentric portion 36 and the roller 43 gradually flows downward by gravity and reaches the upper end of the side wall of the gap 90. The lubricating oil 21 that reaches the upper end of the side wall of the gap 90 flows toward the lower end of the side wall of the gap 90 and is stored in the gap 90. Hereinafter, this gap 90 is referred to as a storage space 90 that temporarily stores the lubricating oil 21.

The auxiliary bearing 17 has a through passage 91 that passes through the auxiliary bearing 17 and connects the storage space 90 to the inside of the sealed container 11. In other words, the storage space 90 in the compression mechanism 13 and the sealed container 11 that houses the compression mechanism 13 are connected through the through passage 91 of the auxiliary bearing 17.

The through passage 91 has an L-shape in vertical cross section. An opening at one end of the through passage 91 is open to the storage space 90. An opening at the other end of the through passage 91 is open to the side of the auxiliary bearing 17. The through passage 91 is formed, for example, by a drill. The auxiliary bearing 17 may have multiple through passages 91. The multiple through passages 91 are preferably spaced apart in the circumferential direction of the auxiliary bearing 17. The multiple through passages 91 may be spaced apart at equal intervals or different intervals. The multiple through passages 91 can increase the flow rate of the lubricating oil 21 and can easily prevent clogging with dirt.

3, the auxiliary bearing 17 of the compressor 2 according to this embodiment has a recessed step 92 provided on the upper surface of the auxiliary bearing 17 and leading to the gap 90. The step 92 is recessed in a dish shape with a vertical dimension shorter than the radial dimension of the auxiliary bearing 17. The step 92 is located below the storage space 90 and defines a space integral with the storage space 90. In other words, the step 92 functions as the storage space 90 for the lubricating oil 21 together with the gap 90.

As shown in FIG. 4, the step portion 92 of the compressor 2 according to this embodiment is circular in plan view. The dimensions of the outer peripheral edge portion of the step portion 92 are set so that it is not blocked by the roller 43 and connected to the cylinder chamber 41. In other words, the step portion 92 has dimensions and is arranged so that it is located inside the trajectory of the eccentric portion 36 and the roller 43 when they rotate eccentrically. The roller 43 that fits into the eccentric portion 36 moves eccentrically around the center of the auxiliary bearing 17. The two-dot chain line in FIG. 4 indicates the position where the roller 43 exists at every 90-degree rotation position of the eccentric portion 36. As is clear from FIG. 4, the step portion 92 is located inside the roller 43 during the entire process of the eccentric movement of the roller 43. In other words, the step portion 92 is provided on the upper surface of the auxiliary bearing 17 in a range where it is not blocked by the roller 43 and connected to the cylinder chamber 41.

The through passage 91 connects the step portion 92 to the inside of the sealed container 11. That is, an opening at one end of the through passage 91, which opens to the storage space 90, is provided in the step portion 92 and opens toward the gap 90.

The auxiliary bearing 17 has a ring-shaped groove 93 that is larger in diameter than the inner peripheral surface 78, i.e., the portion that supports the lower end portion 15b of the rotating shaft 15. This ring-shaped groove 93 is open toward the upper side of the auxiliary bearing 17 and communicates with the gap 90 and the step portion 92. The groove 93 functions as a storage space 90 for the lubricating oil 21 together with the gap 90, similar to the step portion 92. In other words, the groove 93 defines a space that is integrated with the storage space 90. The groove 93 is also provided on the inner peripheral side of the auxiliary bearing 17 than the through passage 91. In other words, the groove 93 is connected to the through passage 91 via the step portion 92. The through passage 91 may be directly connected to the groove 93. Furthermore, the groove 93 also has the function of imparting flexibility to the auxiliary bearing 17.

As shown by the solid arrow in FIG. 2, the lubricating oil 21 pumped up from the sealed container 11 by the pump 65 is supplied from the third cylinder oil supply hole 73C to the gap between the eccentric part 36 and the roller 43 housed in the third cylinder 42C. Furthermore, the lubricating oil 21 is collected downward by gravity, and flows into the gap 90 from the gap between the eccentric part 36 and the roller 43. The lubricating oil 21 that reaches the upper end of the side wall of the gap 90 flows toward the lower end of the side wall of the gap 90 and is temporarily stored in the gap 90. Since the gap 90 defines a storage space 90 integrated with the step part 92 and the ring-shaped groove part 93, the lubricating oil 21 is also stored in the step part 92 and the ring-shaped groove part 93. Note that it is sufficient that the storage space 90 has at least the gap 90. The storage space 90 may have the gap 90 and the groove part 93, except for the step part 92.

The lubricating oil 21 that has accumulated in the gap 90, the step portion 92, and the groove portion 93 branches into the gap between the rotating shaft 15 and the auxiliary bearing 17 and into the through passage 91, and is discharged from the compression mechanism 13. The lubricating oil 21 that has flowed into the gap between the rotating shaft 15 and the auxiliary bearing 17 moves downward by gravity and flows out from the oil supply mechanism insertion hole 68 into the sealed container 11. The lubricating oil 21 that has flowed into the through passage 91 flows out into the sealed container 11 through the through passage 91. In other words, the lubricating oil 21 sucked up by the oil supply mechanism 22 branches into the gap between the rotating shaft 15 and the auxiliary bearing 17 and into the through passage 91, and returns to the sealed container 11 side, generating a circulating flow F1 to lubricate the third cylinder 42C and its surroundings.

Figure 5 is an enlarged vertical cross-sectional view of the compressor related to the first embodiment of the present invention.

5, the rotating shaft 15 of the compressor 2 according to this embodiment has an oil supply groove 81 provided on the outer circumferential surface 77 of the portion supported by the auxiliary bearing 17, and extending in the opposite direction to the rotation direction of the rotating shaft 15 and toward the third cylinder 42C. In other words, the oil supply groove 81 faces the inner circumferential surface 78 of the auxiliary bearing 17. The oil supply groove 81 is recessed toward the rotation center line C of the rotating shaft 15, connects to the auxiliary bearing oil supply hole 75B, and extends from the connection portion with the auxiliary bearing oil supply hole 75B to reach the third cylinder 42C. The oil supply groove 81 extends in a spiral shape along the outer circumferential surface 77 of the rotating shaft 15. In the compressor 2 that rotates the rotating shaft 15 counterclockwise in a plan view, the oil supply groove 81 draws a clockwise spiral from the connection portion with the auxiliary bearing oil supply hole 75B toward the third cylinder 42C.

When the lower end side of the secondary bearing 17 is used as a reference, the oil supply groove 81 describes a clockwise spiral from the lower end to the upper end of the secondary bearing 17. When the upper end side of the secondary bearing 17 is used as a reference, the oil supply groove 81 describes a counterclockwise spiral from the upper end to the lower end of the secondary bearing 17.

In the lubrication structure for the rotating shaft 15 and the secondary bearing 17 configured as described above, the lubricating oil 21 is pumped up into the pump arrangement hole 69 of the rotating shaft 15 by the pump 65 that rotates integrally with the rotating shaft 15 and flows out of the secondary bearing oil supply hole 75B, and flows into the oil supply groove 81 of the rotating shaft 15 to lubricate the gap between the rotating shaft 15 and the secondary bearing 17. The lubricating oil 21 that has flowed into the oil supply groove 81 of the rotating shaft 15 creates a flow F2 from the secondary bearing oil supply hole 75B toward the third cylinder 42C as the rotating shaft 15 rotates, lubricating the range S1 above the secondary bearing oil supply hole 75B.

The lubrication structure between the rotating shaft 15 and the auxiliary bearing 17 adjusts the amount of oil supplied to the sliding portion between the rotating shaft 15 and the auxiliary bearing 17 by appropriately setting at least one of the flow passage cross-sectional area of the oil supply groove 81, the flow passage length of the oil supply groove 81, the inclination of the oil supply groove 81 relative to the rotation center line C of the rotating shaft 15, and the cross-sectional area of the auxiliary bearing oil supply hole 75B connecting the oil supply groove 81 and the oil passage 66 upstream of it.

The flow passage cross-sectional area of the oil supply groove 81 is set by a combination of the groove depth and groove width of the oil supply groove 81.

Furthermore, the length of the oil groove 81 according to this embodiment is shorter than the length around the outer circumferential surface 77 of the rotating shaft 15. In other words, the oil groove 81 does not go around the rotating shaft 15. The oil groove 81 of the rotating shaft 15 is constantly supplied with the lubricating oil 21 pumped up by the pump 65.

However, if the lubricating oil 21 leaks excessively into the second discharge muffler 56, the balancer 38 in the second discharge muffler 56 may reduce the function of adjusting the imbalance of the rotating body of the compression mechanism 13. Therefore, the oil supply groove 81 is open to the inside (storage space 90) of the roller 43 of the third cylinder 42C. In other words, the oil supply groove 81 allows the lubricating oil 21 to flow out to the inside of the roller 43 of the third cylinder 42C.

As described above, the compressor 2 and the refrigeration cycle device 1 according to this embodiment have a through passage 91 that connects the storage space 90 (gap 90) that stores the lubricating oil 21 that is surrounded by the lower surface of the eccentric portion 36 of the rotating shaft 15, the inner peripheral surface of the roller 43, and the upper surface of the auxiliary bearing 17 and is guided by the oil supply mechanism 22 and supplied to the compression mechanism 13, and the inside of the sealed container 11 through the auxiliary bearing 17. Therefore, the lubricating oil 21 sucked up by the oil supply mechanism 22 is supplied from the third cylinder oil supply hole 73C and temporarily stored in the storage space 90 (gap 90). This storage space 90 reduces the amount of lubricating oil 21 that flows into the space partitioned by the auxiliary bearing 17 and the second discharge muffler 56 from the gap between the parts. Furthermore, the through passage 91 discharges the lubricating oil 21 temporarily stored in the storage space 90 (gap 90) into the sealed container 11. This makes it even more difficult for the lubricating oil 21 to flow into the space defined by the auxiliary bearing 17 and the second discharge muffler 56. In other words, the through passage 91 can reduce the amount of lubricating oil 21 supplied to the space defined by the auxiliary bearing 17 and the second discharge muffler 56. This reduces the risk that the operation of the balancer 38 housed in the second discharge muffler 56 will be hindered by the lubricating oil 21, and maintains the function of the balancer 38 to adjust the imbalance of the rotating body. As a result, the performance and reliability of the compressor 2 and the refrigeration cycle device 1 can be improved.

The compressor 2 and the refrigeration cycle device 1 also have an oil passage 66 including a third cylinder oil supply hole 73C that supplies the lubricating oil 21 guided to the compression mechanism 13 by the oil supply mechanism 22 to the gap between the auxiliary bearing 17 and the rotating shaft 15, and an oil supply groove 81 that is provided on the outer circumferential surface 77 of the portion supported by the auxiliary bearing 17 and extends toward the cylinder chamber 41. Therefore, the amount of oil supplied from the oil passage 66 and the oil supply groove 81 to the storage space 90 increases. If the amount of oil supplied to the storage space 90 increases, the discharge of the lubricating oil 21 stored in the storage space 90 is promoted, and the reliability of the compressor 2 and the refrigeration cycle device 1 is improved.

Furthermore, the compressor 2 and the refrigeration cycle device 1 according to this embodiment have a recessed step portion 92 provided on the upper surface of the auxiliary bearing 17 and leading to the gap 90, and a through passage 91 connecting the step portion 92 and the inside of the sealed container 11. Therefore, the compressor 2 and the refrigeration cycle device 1 can collect the lubricating oil 21 guided downward by gravity in the step portion 92 and smoothly discharge the lubricating oil 21 collected in the step portion 92 through the through passage 91, thereby improving the reliability of the compressor 2 and the refrigeration cycle device 1.

Second Embodiment
FIG. 6 is a vertical sectional view of a sub-bearing of a compressor according to a second embodiment of the present invention.

6, the compressor 2 and the auxiliary bearing 17A of the refrigeration cycle device 1 according to this embodiment have a portion that supports the rotating shaft 15, that is, a ring-shaped groove 93A that is provided with a larger diameter than the inner peripheral surface 78 of the auxiliary bearing 17A and opens toward the top of the auxiliary bearing 17A and leads to the gap 90, and a through passage 91A that connects the ring-shaped groove 93 and the inside of the sealed container 11. The through passage 91A also connects the lower end of the ring-shaped groove 93A and the inside of the sealed container 11. In other words, the lubricating oil 21 stored in the ring-shaped groove 93A is discharged to the sealed container 11 side through the through passage 91A.

The secondary bearing 17A according to this embodiment has a step portion 92, similar to the secondary bearing 17 according to the first embodiment. A ring-shaped groove portion 93 is provided in the step portion 92. Therefore, the lubricating oil 21 guided downward by gravity is collected in the step portion 92, and is further collected from the step portion 92 in the ring-shaped groove portion 93A. The lubricating oil 21 stored in the groove bottom of the ring-shaped groove portion 93A is then discharged to the sealed container 11 side through the through passage 91A.

As described above, the compressor 2 and the refrigeration cycle device 1 according to this embodiment have a ring-shaped groove 93A that is larger in diameter than the portion supporting the rotating shaft 15, opens toward the upper side of the auxiliary bearing 17A, and leads to the storage space 90, and a through passage 91 that connects the ring-shaped groove 93A to the inside of the sealed container 11. Therefore, the compressor 2 and the refrigeration cycle device 1 can collect the lubricating oil 21 guided downward by gravity in the ring-shaped groove 93A and smoothly discharge the lubricating oil 21 collected in the groove 93A through the through passage 91. Moreover, the ring-shaped groove 93A also has the function of imparting flexibility to the auxiliary bearing 17A, thereby improving the reliability of the compressor 2 and the refrigeration cycle device 1.

Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the gist of the invention. These embodiments and their modifications are included within the scope and gist of the invention, and are included in the scope of the invention and its equivalents as set forth in the claims.

1...refrigeration cycle device, 2...rotary compressor, 3...radiator, 5...expansion device, 6...heat absorber, 7...accumulator, 8...refrigerant piping, 8a...discharge pipe, 11...sealed container, 11a...body, 11b...head plate, 11c...head plate, 12...open winding type motor section, 13...compression mechanism section, 15...rotating shaft, 15a...middle section, 15b...lower end section, 16...main bearing, 17, 17A...auxiliary bearing, 21...lubricating oil , 22...oil supply mechanism, 25, 26...sealed terminal, 27, 28...terminal block, 29...power line, 31...stator, 32...rotor, 33...lead wire, 35...rotor core, 36...eccentric portion, 38...balancer, 38a...through hole, 41...cylinder chamber, 42...cylinder, 42A...first cylinder, 42C...third cylinder, 42B...second cylinder, 43...roller, 45A...first partition plate, 4 5B...second partition plate, 46...fastening member, 51A...first discharge valve mechanism, 51B...second discharge valve mechanism, 51C...third discharge valve mechanism, 52...first discharge muffler, 53...discharge chamber, 55...fastening member, 56...second discharge muffler, 57...second hole, 58...frame, 59...fastening member, 61...suction pipe, 61A...first suction pipe, 61B...second suction pipe, 61C...third suction pipe, 65...pump, 66...oil passage, 68...Oil supply mechanism insertion hole, 69...Pump arrangement hole, 71...Rotor, 73A...First cylinder oil supply hole, 73B...Second cylinder oil supply hole, 73C...Third cylinder oil supply hole, 75A...Main bearing oil supply hole, 75B...Auxiliary bearing oil supply hole, 77...Outer peripheral surface of rotating shaft, 78...Inner peripheral surface of auxiliary bearing, 81...Oil supply groove, 90...Storage space, 91, 91A...Through passage, 92...Step portion, 93, 93A...Ring-shaped groove portion.

Claims (2)

A cylindrical sealed container having a center line extending in the vertical direction;
a compression mechanism portion that is accommodated in the sealed container and compresses a refrigerant that is introduced into the sealed container;
an electric motor unit including a cylindrical stator fixed to an inner surface of the sealed container and a rotor disposed inside the stator to generate a rotational driving force for the compression mechanism unit;
an oil supply mechanism that supplies the lubricating oil stored in the sealed container to the compression mechanism,
The compression mechanism includes:
a rotating shaft that rotates integrally with the rotor, extends downward from the rotor, and has an eccentric portion;
a roller having a lower surface located below a lower surface of the eccentric portion and fitted to the eccentric portion;
A sub-bearing that rotatably supports a lower end of the rotating shaft;
a cylinder having a cylinder chamber that is closed by the auxiliary bearing and that houses the eccentric portion and the roller;
a sub-muffler that covers the sub-bearing and separates a space into which the refrigerant compressed in the cylinder is discharged;
a balancer that is provided on a protruding portion of the rotating shaft that protrudes from the sub-bearing and is housed in the sub-muffler,
The auxiliary bearing has a through passage that connects a storage space that stores the lubricating oil supplied to the compression mechanism by the oil supply mechanism and the inside of the sealed container, the storage space being surrounded by a lower surface of the eccentric portion, an inner peripheral surface of the roller, and an upper surface of the auxiliary bearing, through the auxiliary bearing,
The through passage has a first opening arranged on a side surface of the sub-bearing and opening into the sealed container, and a second opening arranged on an upper surface of the sub-bearing and opening into the storage space, and penetrates the sub-bearing in an L-shape;
The rotation shaft is
an oil supply hole that supplies lubricating oil guided to the compression mechanism by the oil supply mechanism to a gap between the auxiliary bearing and the compression mechanism;
an oil supply groove provided on an outer peripheral surface of a portion supported by the auxiliary bearing, extending toward the cylinder chamber and reaching the cylinder;
The auxiliary bearing has a recessed step portion provided on an upper surface of the auxiliary bearing and communicating with the storage space,
The through passage connects the step portion and the inside of the sealed container,
The step portion is recessed in a dish shape and is positioned inside the rotation path described by the roller as the rotating shaft rotates. A compressor according to claim 1;
A heat sink;
An expansion device;
A heat sink;
a refrigerant pipe that connects the compressor, the radiator, the expansion device, and the heat absorber and through which the refrigerant flows.

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