Scroll compressor
By designing the bearing support to be separate from the rotating shaft in the scroll compressor, the problems of high friction loss and high manufacturing cost are solved, resulting in a more efficient and economical bearing system.
Patent Information
- Application Number
- CN202480042944.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-11-30
- Filing Date
- 2024-07-17
- Publication Date
- 2026-01-23
AI Technical Summary
Existing scroll compressors suffer from high frictional losses and high manufacturing costs in their bearing design, especially in the eccentric part of the rotating shaft.
The first and second bearings are overlapped in the axial direction of the rotating shaft and separated from the rotating shaft by bearing supports. External cylindrical grinding is used to reduce friction loss and lower manufacturing costs.
By reducing frictional losses and lowering manufacturing costs, the efficiency and reliability of scroll compressors have been improved.
Smart Images
Figure CN121399375A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present disclosure relates to scroll compressors, and more particularly, to a scroll compressor in which a first bearing provided between a main frame and a rotating shaft and a second bearing provided between a moving scroll and the rotating shaft are arranged to overlap in an axial direction. BACKGROUND
[0002] A compressor is a mechanical device that increases pressure by compressing air, refrigerant, or various other working gases using a motor, a turbine, or the like. Compressors are used in various ways throughout various industries.
[0003] When a compressor is used in a refrigerant cycle, the compressor can convert low-pressure refrigerant into high-pressure refrigerant and deliver it back to a condenser.
[0004] Compressors can be roughly classified into a reciprocating compressor that forms a compression space between a piston and a cylinder in which suction refrigerant and discharge refrigerant are taken in and out and that compresses refrigerant as the piston linearly reciprocates inside the cylinder, a rotary compressor that forms a compression space between an eccentrically rotating rolling piston and a cylinder in which suction refrigerant and discharge refrigerant are taken in and out and that compresses refrigerant as the rolling piston eccentrically rotates along the inner wall of the cylinder, and a scroll compressor that forms a compression space between a moving scroll and a fixed scroll in which suction refrigerant and discharge refrigerant are taken in and out and that compresses refrigerant as the moving scroll rotates with respect to the fixed scroll.
[0005] Scroll compressors are widely used in refrigeration cycle devices because they have higher efficiency, lower vibration and noise, and can be compact and light in weight compared to reciprocating compressors or rotary compressors. SUMMARY
[0006] TECHNICAL SOLUTION
[0007] According to one or more embodiments of the disclosure, a scroll compressor can include a main frame including a shaft hole, a fixed scroll disposed on an upper side of the main frame, an orbiting scroll disposed in a space formed by the fixed scroll and the main frame, a lower surface of the orbiting scroll including a boss inserted into the shaft hole of the main frame, a rotatable shaft including an eccentric portion inserted into the boss of the orbiting scroll and inserted into the shaft hole of the main frame, a first bearing disposed in the shaft hole between the shaft hole of the main frame and a bearing support coupled to an outer circumferential surface of the rotatable shaft, and a second bearing disposed between the boss of the orbiting scroll and the eccentric portion of the rotatable shaft. A position of the second bearing overlaps the first bearing in an axial direction of the rotatable shaft. An inner circumferential surface of the first bearing can be supported by an outer circumferential surface of the bearing support, and the bearing support can be separable from and couplable to the rotatable shaft.
[0008] According to one or more embodiments of the disclosure, the bearing support can have a hollow cylindrical shape, and the bearing support can be press-fitted to an outer circumferential surface of an upper end of the rotatable shaft.
[0009] According to one or more embodiments of the disclosure, the upper end of the rotatable shaft can include a stepped portion located below the eccentric portion, and the bearing support is coupled to the stepped portion.
[0010] According to one or more embodiments of the disclosure, an inner circumferential surface of the bearing support can be eccentric with respect to an outer circumferential surface of the bearing support.
[0011] According to one or more embodiments of the disclosure, the scroll compressor can further include a balance weight disposed on the rotatable shaft, wherein the bearing support can integrally extend upward from the balance weight in the axial direction of the rotatable shaft.
[0012] According to one or more embodiments of the disclosure, the rotatable shaft can be press-fitted into a fixing hole of the balance weight such that the rotatable shaft is coupled to the balance weight.
[0013] According to one or more embodiments of the disclosure, the bearing support can include an oil hole.
[0014] According to one or more embodiments of the disclosure, the first bearing and the second bearing can be oil-free bearings.
[0015] According to one or more embodiments of the present disclosure, an outer circumferential surface of the first bearing can be fixed to the shaft hole of the main frame, and an inner circumferential surface of the first bearing can support an outer circumferential surface of the bearing support in such a manner that the bearing support is rotatable.
[0016] According to one or more embodiments of the present disclosure, an outer circumferential surface of the second bearing can be fixed to an inner circumferential surface of the boss of the orbiting scroll, and an inner circumferential surface of the second bearing can support an outer circumferential surface of the eccentric portion of the rotatable shaft in such a manner that the eccentric portion is rotatable.
[0017] According to one or more embodiments of the present disclosure, a scroll compressor can include a main frame including a shaft hole, a fixed scroll disposed on an upper side of the main frame, an orbiting scroll disposed in a space formed by the fixed scroll and the main frame, a lower surface of the orbiting scroll including a boss inserted into the shaft hole of the main frame, a rotatable shaft including an eccentric portion inserted into the boss of the orbiting scroll and inserted into the shaft hole of the main frame, a first bearing disposed in the shaft hole between the shaft hole of the main frame and the rotatable shaft, a second bearing disposed between the boss of the orbiting scroll and the eccentric portion of the rotatable shaft, and a bearing support having a hollow cylindrical shape, the bearing support being separable from and couplable to an outer circumferential surface of an upper end of the rotatable shaft to support an inner circumferential surface of the first bearing, wherein a portion of the second bearing can be located in a hollow portion of the bearing support.
[0018] According to one or more embodiments of the present disclosure, a lower end of the second bearing can be located below an upper end of the first bearing in an axial direction of the rotatable shaft.
[0019] According to one or more embodiments of the present disclosure, the bearing support can be press-fitted to the outer circumferential surface of the upper end of the rotatable shaft.
[0020] According to one or more embodiments of the present disclosure, the scroll compressor can further include a balance weight disposed on the rotatable shaft below the main frame, wherein the bearing support can integrally extend upward from the balance weight in an axial direction of the rotatable shaft.
[0021] According to one or more embodiments of the present disclosure, the balance weight can include a fixed hole eccentric with respect to the hollow of the bearing support, and the rotatable shaft is press-fitted into the fixed hole of the balance weight such that the rotatable shaft is coupled with the balance weight. BRIEF DESCRIPTION OF DRAWINGS
[0022] These and / or other aspects, features, and advantages of some embodiments of the present disclosure will become apparent and more readily appreciated from the following description, taken in conjunction with the accompanying drawings, in which:
[0023] Figure 1 is a perspective view illustrating a scroll compressor according to one or more embodiments of the present disclosure.
[0024] Figure 2 is a sectional view illustrating a scroll compressor according to one or more embodiments of the present disclosure.
[0025] Figure 3 is a partial enlarged sectional view illustrating a compression part of a scroll compressor according to one or more embodiments of the present disclosure.
[0026] Figure 4 is a sectional view illustrating Figure 3 a compression part of a scroll compressor according to one or more embodiments of the present disclosure.
[0027] Figure 5 is an exploded perspective view illustrating main parts of a scroll compressor according to one or more embodiments of the present disclosure.
[0028] Figure 6 is a bottom perspective view illustrating a moving scroll of a scroll compressor according to one or more embodiments of the present disclosure.
[0029] Figure 7 is a partial perspective view illustrating a bearing support and an eccentric part of a rotating shaft of a scroll compressor according to one or more embodiments of the present disclosure.
[0030] Figure 8 is a sectional view illustrating a rotating shaft of a scroll compressor according to one or more embodiments of the present disclosure.
[0031] Figure 9 is a partial enlarged sectional view illustrating a compression part of a scroll compressor according to one or more embodiments of the present disclosure.
[0032] Figure 10 is an exploded perspective view illustrating main parts of a scroll compressor according to one or more embodiments of the present disclosure.
[0033] Figure 11 is a sectional view illustrating Figure 9a partial enlarged sectional view of the B portion of FIG. 1.
[0034] Figure 12 is a perspective view illustrating a state in which the counterweight according to one or more embodiments of the disclosure is press-fitted into a rotating shaft. DETAILED DESCRIPTION
[0035] Various embodiments of the present document and the terms used therein are not intended to limit the technical features described in the present document to particular embodiments, but are to be understood as including various modifications, equivalents, or alternatives of the embodiments.
[0036] With regard to the description of the drawings, similar reference numerals can be used for similar or related components.
[0037] The singular form of a noun corresponding to an object can include one or more of the object, unless the relevant context clearly dictates otherwise.
[0038] In the present document, each of the phrases such as "A or B", "at least one of A and B", "at least one of A or B", "A, B, or C", "at least one of A, B, and C", "at least one of A, B, C" can include any one of the listed items or any possible combination thereof, together with the corresponding phrase.
[0039] The term "and / or" includes any of the plurality of related described elements or combination thereof.
[0040] Terms such as "first", "second", "main", or "sub" can simply be used to distinguish one component from other components, and do not limit the corresponding component in other aspects (for example, importance or order), unless explicitly specified otherwise.
[0041] When one (for example, first) component is said to be "coupled" or "connected" to another (for example, second) component with or without the term "functionally" or "communicatively", it means that the one component can be connected to the other component directly (for example, wired), wirelessly, or through a third component.
[0042] Terms such as "include" or "have" are intended to specify the presence of the described features, numbers, steps, operations, components, components, or combinations thereof in the embodiments, but do not exclude the presence or addition of one or more other features, numbers, steps, operations, components, components, or combinations thereof.
[0043] When a part is referred to as being "connected", "coupled", "supported", or "contacted" to another part, it means not only that the parts are directly connected, coupled, supported, or contacted to each other but also that the parts are indirectly connected, coupled, supported, or contacted to each other by a third part.
[0044] When a part is referred to as being "on" another part, it includes not only the case where the part is in contact with the other part but also the case where another part is present between the two parts.
[0045] In addition, the terms "front end", "rear end", "upper side", "lower side", "top end", "bottom end", and the like used in the disclosure are defined with reference to the accompanying drawings. However, the shape and position of each part are not limited by these terms.
[0046] The disclosure relates to a scroll compressor, when a first bearing provided between a rotating shaft and a main frame and a second bearing provided between the rotating shaft and a moving scroll overlap in an axial direction, a bearing support is formed separately from the rotating shaft so that an outer circumferential surface of an eccentric portion of the rotating shaft can be lapped by external cylindrical lapping, which can reduce friction loss of the second bearing and manufacturing cost of the rotating shaft.
[0047] Hereinafter, a scroll compressor 1 according to one or more embodiments of the disclosure will be described with reference to the accompanying drawings. Figures 1 to 7 The scroll compressor 1 according to one or more embodiments of the disclosure will be described in detail.
[0048] Figure 1 is a perspective view illustrating a scroll compressor 1 according to one or more embodiments of the disclosure. Figure 2 is a cross-sectional view illustrating a scroll compressor 1 according to one or more embodiments of the disclosure. Figure 3 is a partially enlarged cross-sectional view illustrating a compression part of the scroll compressor 1 according to one or more embodiments of the disclosure. Figure 4 is a cross-sectional view illustrating Figure 3 a compression part of the scroll compressor 1 of Figure 5 is an exploded perspective view illustrating main parts of a scroll compressor 1 according to one or more embodiments of the disclosure. Figure 6 is a bottom perspective view illustrating a moving scroll 50 of a scroll compressor 1 according to one or more embodiments of the disclosure. Figure 7 is a partially perspective view illustrating a bearing support 70 and an eccentric portion 62 of a rotating shaft 60 of a scroll compressor 1 according to one or more embodiments of the disclosure.
[0049] Reference will now be made in detail to embodiments of the disclosure, examples of which are illustrated in the accompanying drawings. Figures 1 to 5According to one or more embodiments of the present disclosure, a scroll compressor 1 can include a housing 10, a main frame 20, a sub-frame 30, a fixed scroll 40, an orbiting scroll 50, a rotating shaft 60, and a drive motor 80.
[0050] The housing 10 is airtight container having a cylindrical shape, and can include an upper housing 11 and a lower housing 12. The housing 10 can be formed to accommodate the main frame 20, the sub-frame 30, the fixed scroll 40, the orbiting scroll 50, the rotating shaft 60, and the drive motor 80.
[0051] The housing 10 can be provided with a refrigerant inlet pipe 13 through which a refrigerant is introduced, and a refrigerant discharge pipe 15 through which a refrigerant is discharged.
[0052] The refrigerant inlet pipe 13 penetrates the housing 10, and has one end connected to the fixed scroll 40. The refrigerant discharge pipe 15 penetrates the housing 10, and one end of the refrigerant discharge pipe 15 can communicate with the inside of the housing 10.
[0053] Accordingly, a refrigerant can flow into the fixed scroll 40 provided in the housing 10 through the refrigerant inlet pipe 13, and the compressed refrigerant discharged from the fixed scroll 40 can be discharged to the outside of the housing 10 through the refrigerant discharge pipe 15.
[0054] A base 18 supporting the housing 10 can be provided at the bottom of the lower housing 12. The scroll compressor 1 can be disposed perpendicular to a support surface by means of the base 18.
[0055] The main frame 20 and the sub-frame 30 are vertically spaced apart by a predetermined distance. The main frame 20 and the sub-frame 30 are fixed inside the housing 10. The drive motor 80 rotating the orbiting scroll 50 is disposed between the main frame 20 and the sub-frame 30.
[0056] The fixed scroll 40 and the orbiting scroll 50 can be disposed on the upper side of the main frame 20.
[0057] An oil reservoir 16 storing oil or lubricating oil for lubricating and cooling components accommodated inside the housing 10 can be provided below the sub-frame 30 in the lower portion of the housing 10.
[0058] The main frame 20 can be formed in a substantially disc shape. A shaft hole 21 can be formed in the main frame 20. The shaft hole 21 can be formed at the center of the main frame 20. A first bearing 27 supporting the rotating shaft 60 can be disposed in the shaft hole 21.
[0059] The shaft hole 21 can be formed to have a stepped portion 26. The stepped portion 26 can be formed at an upper end of the shaft hole 21, that is, at a portion adjacent to the orbiting scroll 50. The stepped portion 26 can be formed in an annular shape. The stepped portion 26 can be formed along the entire circumference of the shaft hole 21. The stepped portion 26 is formed to have a diameter smaller than that of the shaft hole 21. The stepped portion 26 is formed to have a diameter smaller than that of the inner diameter of the first bearing 27.
[0060] The first bearing 27 is formed in a hollow cylindrical shape. An outer circumferential surface of the first bearing 27 can be fixed to the shaft hole 21 of the main frame 20. An inner circumferential surface of the first bearing 27 can support the rotation of the rotation shaft 60.
[0061] The first bearing 27 can be formed as an oil-free bearing. For example, the first bearing 27 can be formed as a DU bushing, that is, a self-lubricating bushing.
[0062] The receiving recess 22 can be provided on an upper surface of the main frame 20. The receiving recess 22 can be formed on the upper surface of the main frame 20 to a predetermined depth. Here, the upper surface of the main frame 20 refers to one surface of the main frame 20 on which the fixed scroll 40 is provided.
[0063] The receiving recess 22 can be formed as a circular recess. A bottom surface of the receiving recess 22 can be formed to be flat. The shaft hole 21 can be formed at a bottom portion of the receiving recess 22.
[0064] The upper protrusion 23 can be formed at the bottom portion of the receiving recess 22. The upper protrusion 23 can be formed at an edge of the shaft hole 21. The upper protrusion 23 can be formed to protrude upward from the bottom portion of the receiving recess 22. The upper protrusion 23 can be formed along the entire circumference of the shaft hole 21. The upper protrusion 23 can be formed in an annular shape.
[0065] The sealing recess 24 can be formed on an upper surface of the upper protrusion 23. The sealing recess 24 can be formed adjacent to the shaft hole 21. The sealing recess 24 can be formed at the stepped portion 26. The sealing recess 24 can be formed in an annular shape. The sealing recess 24 can be formed on the upper surface of the upper protrusion 23 to a predetermined depth. For example, a cross-section of the sealing recess 24 can be formed in a U shape having a substantially flat bottom portion. The seal 25 can be provided in the sealing recess 24.
[0066] An Oldham's ring 29 can be provided on the bottom portion of the receiving recess 22. In other words, the Oldham's ring 29 can be provided between the upper protrusion 23 and a side wall of the main frame 20. The Oldham's ring 29 is provided to prevent the orbiting scroll 50 from rotating on its own axis.
[0067] A plurality of mounting holes 201 can be provided at the edge of the upper surface of the main frame 20 to which the fixed scroll 40 is fixed. In detail, the plurality of mounting holes 201 can be formed to surround the receiving groove 22 on the upper surface of the main frame 20. A female screw can be formed on the inner surface of each of the plurality of mounting holes 201.
[0068] A plurality of first refrigerant passages 202 can be provided on the outer circumferential surface of the main frame 20. The plurality of first refrigerant passages 202 can be formed as grooves connecting the upper surface and the lower surface of the main frame 20.
[0069] The fixed scroll 40 is provided on the upper surface of the main frame 20. The fixed scroll 40 is provided to cover the receiving groove 22 of the main frame 20. The fixed scroll 40 can be fixed to the plurality of mounting holes 201 formed on the upper surface of the main frame 20 with a plurality of bolts. The orbiting scroll 50 can be accommodated in the space formed by the fixed scroll 40 and the main frame 20.
[0070] The orbiting scroll 50 is engaged with the fixed scroll 40 and is disposed between the fixed scroll 40 and the main frame 20 so that the orbiting scroll 50 can orbit with respect to the fixed scroll 40.
[0071] The fixed scroll 40 can include a scroll tooth accommodation portion 41, a fixing portion 44 disposed to surround the scroll tooth accommodation portion 41, and a fixed scroll tooth 43 disposed in the inner space of the scroll tooth accommodation portion 41.
[0072] The scroll tooth accommodation portion 41 can be formed in a shape that can be accommodated inside the housing 10. The scroll tooth accommodation portion 41 can be accommodated inside the housing 10 and can be formed in a substantially hollow cylindrical shape. For example, the scroll tooth accommodation portion 41 can include a sidewall having a cylindrical shape and an upper plate formed to block the upper end of the sidewall.
[0073] The outwardly extending fixing portion 44 can be provided at the lower end of the scroll tooth accommodation portion 41. The lower surface of the fixing portion 44, that is, the surface in contact with the mirror plate 51 of the orbiting scroll 50, forms a thrust surface.
[0074] A plurality of through holes 441 for coupling with the main frame 20 can be provided at the edge of the fixing portion 44. Accordingly, the fixed scroll 40 can be fixed to the plurality of mounting holes 201 of the main frame 20 with a plurality of bolts inserted into the plurality of through holes 441 of the fixing portion 44.
[0075] In addition, a plurality of second refrigerant passages 442 can be provided at the edge of the fixing portion 44. The plurality of second refrigerant passages 442 can be formed as grooves connecting the upper surface and the lower surface of the fixing portion 44.
[0076] The plurality of second refrigerant passages 442 can be formed to correspond to the plurality of first refrigerant passages 202 of the main frame 20. The refrigerant discharged to the upper side of the fixed scroll 40 can move to the lower side of the main frame 20 through the plurality of first refrigerant passages 202 of the main frame 20 and the plurality of second refrigerant passages 442 of the fixed scroll 40.
[0077] The upper plate of the scroll wrap accommodation portion 41 is formed in a disc shape, and can be provided with a discharge port 45 through which the refrigerant is discharged, and a plurality of bypasses. A check valve configured to open and close the discharge port 45, and a plurality of bypass valves configured to open and close the plurality of bypasses can be provided on the upper surface of the upper plate.
[0078] A fixed mirror surface can be formed on the lower surface of the upper plate facing the orbiting scroll 50. Accordingly, the upper end of the orbiting scroll wrap 52 of the orbiting scroll 50 can contact the fixed mirror surface of the fixed scroll 40.
[0079] The fixed scroll wrap 43 is disposed in the scroll wrap accommodation portion 41. The fixed scroll wrap 43 extends perpendicularly from the fixed mirror surface of the scroll wrap accommodation portion 41, and can be formed as a helically curved surface having a predetermined thickness and height. For example, the fixed scroll wrap 43 can be formed as an involute curve, an algebraic spiral curve, a hybrid curve, or the like.
[0080] A helical space, i.e., a spiral space, is formed in the inner space of the scroll wrap accommodation portion 41 by the fixed scroll wrap 43. The orbiting scroll wrap 52 of the orbiting scroll 50 is inserted into the spiral space of the scroll wrap accommodation portion 41 of the fixed scroll 40.
[0081] The discharge port 45 can be formed at the center of the scroll wrap accommodation portion 41 so as to penetrate the upper plate thereof. In other words, the discharge port 45 can be formed adjacent to the center of the spiral space formed by the fixed scroll wrap 43.
[0082] An inlet 46 through which the refrigerant flows can be formed on the side surface of the fixed scroll 40. The inlet 46 can be connected to the refrigerant inlet pipe 13 provided in the housing 10. Accordingly, the refrigerant introduced through the refrigerant inlet pipe 13 can be suctioned into the fixed scroll 40 through the inlet 46.
[0083] In detail, the inlet 46 is formed to penetrate the side wall of the scroll wrap accommodation portion 41. The inlet 46 can be formed adjacent to the outer end of the spiral space formed in the scroll wrap accommodation portion 41. Accordingly, the refrigerant can flow into the spiral space of the fixed scroll 40 through the inlet 46.
[0084] An oil groove 47 can be formed on the lower surface, i.e., the thrust surface of the fixed scroll 40. The oil groove 47 can be formed on the thrust surface with a predetermined depth. For example, the cross section of the oil groove 47 can be formed in a substantially U shape having a flat bottom. The oil groove 47 can be formed in an arc shape around the inner space of the scroll tooth accommodation portion 41.
[0085] The orbiting scroll 50 is disposed below the fixed scroll 40 so as to be rotatable with respect to the fixed scroll 40.
[0086] Referring to Figures 2 to 6 The orbiting scroll 50 can include a mirror plate 51, orbiting scroll teeth 52, and a boss 53.
[0087] The mirror plate 51 can be formed in a disc shape having a predetermined thickness and area. An orbiting mirror surface can be formed on the upper surface of the mirror plate 51 facing the fixed scroll 40.
[0088] The orbiting scroll teeth 52 extend perpendicularly from the upper surface, i.e., the orbiting mirror surface, of the mirror plate 51 and can be formed in a spiral shape. The orbiting scroll teeth 52 can be formed to be engaged with the fixed scroll teeth 43 of the fixed scroll 40.
[0089] The orbiting scroll teeth 52 can be formed in a curved surface having a predetermined thickness and height. For example, the orbiting scroll teeth 52 can be formed in an involute curve, an algebraic curve, a hybrid curve, etc.
[0090] The fixed scroll teeth 43 of the fixed scroll 40 and the orbiting scroll teeth 52 of the orbiting scroll 50 are accommodated in the scroll tooth accommodation portion 41 of the fixed scroll 40. The inner space of the scroll tooth accommodation portion 41 of the fixed scroll 40 forms a compression chamber.
[0091] The fixed scroll teeth 43 and the orbiting scroll teeth 52, which are engaged with each other, form a compression chamber, i.e., a plurality of compression pockets. When the orbiting scroll 50 rotates, the plurality of compression pockets compresses the refrigerant sucked into the inlet 46 of the fixed scroll 40, while moving the refrigerant to the center of the scroll tooth accommodation portion 41, and discharges the compressed refrigerant through the discharge port 45.
[0092] The boss 53 can be formed at the center of the lower surface of the mirror plate 51 opposite the orbiting mirror surface. The boss 53 is formed to extend downward from the lower surface of the mirror plate 51. The boss 53 can be formed in a hollow cylindrical shape with one end closed. The outer diameter of the boss 53 can be smaller than the inner diameter of the stepped portion 26 of the main frame 20.
[0093] The upper end of the rotation shaft 60 can be inserted into the hole 54 of the boss 53. That is, the eccentric portion 62 provided at the upper end of the rotation shaft 60 is inserted into the boss 53.
[0094] The second bearing 37 can be provided in the hole 54 of the boss 53. The second bearing 37 is provided to support the eccentric portion 62 of the rotating shaft 60. The second bearing 37 can be formed to have a length corresponding to that of the eccentric portion 62 of the rotating shaft 60. For example, the length of the second bearing 37 can be equal to or shorter than that of the eccentric portion 62 of the rotating shaft 60.
[0095] The second bearing 37 is formed in a hollow cylindrical shape. The outer circumferential surface of the second bearing 37 can be fixed to the hole 54 of the boss 53. The inner circumferential surface of the second bearing 37 can support the rotation of the eccentric portion 62 of the rotating shaft 60. Accordingly, when the rotating shaft 60 rotates, the orbiting scroll 50 can rotate.
[0096] The second bearing 37 can be formed as an oil-free bearing. For example, the second bearing 37 can be formed as a DU bushing (self-lubricating bushing). The first bearing 27 and the second bearing 37 can be formed of the same type of bearing.
[0097] The orbiting scroll 50 is engaged with the fixed scroll 40, and the boss 53 can be inserted into the shaft hole 21 of the main frame 20. In detail, the mirror plate 51 of the orbiting scroll 50 can be located on the upper protruding portion 23 of the main frame 20, and the boss 53 can be positioned in the shaft hole 21.
[0098] When the orbiting scroll 50 is provided in the main frame 20, the boss 53 of the orbiting scroll 50 is inserted into the shaft hole 21 of the main frame 20. At least a portion of the boss 53 of the orbiting scroll 50 can be located inside the shaft hole 21 of the main frame 20. In other words, the lower end of the boss 53 of the orbiting scroll 50 can be located below the upper surface of the upper protruding portion 23 of the main frame 20. For example, the center of the boss 53 in the longitudinal direction of the boss 53 can be located below the upper protruding portion 23 of the main frame 20.
[0099] The second bearing 37 is provided in the hole 54 of the boss 53 of the orbiting scroll 50, and the first bearing 27 is provided in the shaft hole 21 of the main frame 20. Accordingly, at least a portion of the second bearing 37 can be positioned inside the first bearing 27.
[0100] In other words, the first bearing 27 provided between the shaft hole 21 of the main frame 20 and the rotating shaft 60 and the second bearing 37 provided between the boss 53 of the orbiting scroll 50 and the eccentric portion 62 of the rotating shaft 60 can overlap in the axial direction. Here, the axial direction refers to the direction along which the rotating shaft 60 is viewed from one side of the rotating shaft 60. That is, the axial direction refers to the direction along which the rotating shaft 60 is viewed from the side of the main frame 20. Figure 3The second bearing 37 overlaps the first bearing 27, which means that, when viewed in the axial direction, the second bearing 37 is located behind the first bearing 27 and is covered by the first bearing 27. This does not mean that the first bearing 27 and the second bearing 37 are in contact with each other.
[0101] Therefore, as Figure 3 indicated, when viewed in the axial direction S, the lower portion of the second bearing 37 overlaps the upper portion of the first bearing 27.
[0102] The drive motor 80 is disposed below the main frame 20. The drive motor 80 is configured to generate a rotational force to rotate the orbiting scroll 50.
[0103] The drive motor 80 can include a stator 81 and a rotor 82. The stator 81 can be fixed to the inner surface of the housing 10. The rotor 82 can be rotatably disposed inside the stator 81.
[0104] In addition, the rotation shaft 60 can be inserted into the rotor 82 so as to penetrate the rotor 82. Since the rotor 82 is fixed to the rotation shaft 60, the rotor 82 and the rotation shaft 60 can rotate as one body.
[0105] The fixed scroll 40, the orbiting scroll 50, and the rotation shaft 60 can form a compression member that sucks, compresses, and discharges a refrigerant.
[0106] The rotation shaft 60 can include a shaft portion 61 formed to have a predetermined length and an eccentric portion 62 extending upward from an upper end of the shaft portion 61. The eccentric portion 62 can be integrally formed with the shaft portion 61. A central axis CA2 of the eccentric portion 62 is spaced apart from a center of rotation (i.e., a central axis CA1 of the shaft portion 61) of the rotation shaft 60 by a predetermined distance.
[0107] The rotor 82 of the drive motor 80 can be fixed to the shaft portion 61 of the rotation shaft 60. The upper end of the shaft portion 61 can be inserted into the shaft hole 21 of the main frame 20 and can be rotatably supported by the first bearing 27 disposed in the shaft hole 21.
[0108] The eccentric portion 62 formed at the upper end of the rotation shaft 60 can be inserted into the hole 54 of the boss 53 of the orbiting scroll 50. The eccentric portion 62 of the rotation shaft 60 can be supported by the second bearing 37 disposed in the boss 53 of the orbiting scroll 50.
[0109] A bearing support 70 can be provided at an upper end of the rotating shaft 60 (i.e., an upper end of the shaft part 61). The bearing support 70 is provided on the rotating shaft 60 to surround the eccentric part 62. The bearing support 70 can be rotatably supported by a first bearing 27 provided on the main frame 20. That is, the first bearing 27 is interposed between the bearing support 70 and the main frame 20, and can support the rotation of the bearing support 70 coupled to the rotating shaft 60. The bearing support 70 will be described in detail below.
[0110] A balance weight 75 can be provided on the shaft part 61 of the rotating shaft 60 above the rotor 82. The balance weight 75 can be provided below the bearing support 70. The balance weight 75 can be spaced apart from the bearing support 70 by a predetermined distance along the rotating shaft 60. The balance weight 75 can be provided on the shaft part 61 between the rotor 82 and the main frame 20. The balance weight 75 is provided to offset the unbalance caused by the eccentric rotation of the orbiting scroll 50.
[0111] The balance weight 75 can include a fixing hole 751. The balance weight 75 can be fixed to the rotating shaft 60 by inserting the rotating shaft 60 into the fixing hole 751. The balance weight 75 can be fixed to the rotating shaft 60 by press fitting. The diameter of the fixing hole 751 of the balance weight 75 and the diameter of the portion of the rotating shaft 60 on which the balance weight 75 is provided can be defined such that the rotating shaft 60 can be press fitted into the fixing hole 751 of the balance weight 75.
[0112] A lower portion of the shaft part 61 can be supported by a bearing 31 provided on a sub-frame 30 fixed to the housing 10. The bearing 31 of the sub-frame 30 can be formed as a bush bearing. Accordingly, the rotating shaft 60 can be rotated while being supported at both ends thereof by the main frame 20 and the sub-frame 30.
[0113] In addition, an oil passage 66 can be formed in the rotating shaft 60 to pass through the shaft part 61 and the eccentric part 62. An outlet 66a of the oil passage 66 is provided at an upper end of the eccentric part 62.
[0114] An oil pump 33 for supplying oil from the oil reservoir 16 to the oil passage 66 can be provided at a lower end of the rotating shaft 60. A lower end of the oil pump 33 can be immersed in oil contained in the oil reservoir 16 of the housing 10.
[0115] Accordingly, when the rotating shaft 60 is rotated, the oil stored in the oil reservoir 16 can be supplied to the oil passage 66 of the rotating shaft 60 by pressure acting on the oil reservoir 16 and the oil pump 33.
[0116] Oil moving along the oil passage 66 can be supplied to the hole 54 of the boss 53 of the orbiting scroll 50 through the outlet 66a. Further, oil in the hole 54 of the boss 53 can lubricate the second bearing 37 and flow downward.
[0117] Referring to Figure 2 , Figure 3 and Figure 7 , a bearing support 70 can be provided on an outer circumferential surface of the rotating shaft 60. The bearing support 70 can be provided on an outer circumferential surface of an upper end of the shaft part 61 of the rotating shaft 60. The bearing support 70 is formed separately or individually from the rotating shaft 60, and the bearing support 70 can be coupled to the outer circumferential surface of the rotating shaft 60. The bearing support 70 can be coupled to the outer circumferential surface of the upper end of the shaft part 61 of the rotating shaft 60. The bearing support 70 coupled to the rotating shaft 60 can rotate integrally with the rotating shaft 60.
[0118] The bearing support 70 can be formed in a hollow cylindrical shape. The hollow part of the bearing support 70 can be formed eccentric with respect to the outer circumferential surface. In other words, the inner circumferential surface of the bearing support 70 is formed eccentric with respect to the outer circumferential surface of the bearing support 70. That is, the bearing support 70 can be formed such that the center of the inner circumferential surface of the bearing support 70 is eccentric with respect to the center of the outer circumferential surface of the bearing support 70.
[0119] However, in another embodiment, the bearing support 70 can be formed such that the inner circumferential surface and the outer circumferential surface of the bearing support 70 are concentric. That is, the bearing support 70 can be formed such that the center of the inner circumferential surface of the bearing support 70 coincides with the center of the outer circumferential surface of the bearing support 70.
[0120] As shown in Figure 7 , when the hollow part of the bearing support 70 is formed eccentrically, the bearing support 70 can function as a sub balance weight that offsets the unbalance of the orbiting scroll 50. When the hollow part of the bearing support 70 is formed concentrically with the outer circumferential surface, the bearing support 70 does not function as a sub balance weight.
[0121] The bearing support 70 is formed to support the first bearing 27. When the bearing support 70 is coupled to the rotating shaft 60, the bearing support 70 can support the first bearing 27. That is, the outer circumferential surface of the bearing support 70 coupled to the rotating shaft 60 can support the inner circumferential surface of the first bearing 27. Accordingly, the rotating shaft 60 can be rotatably supported by the first bearing 27.
[0122] Because the first bearing 27 is fixed to the main frame 20, the bearing support 70 can rotate with respect to the first bearing 27. The bearing support 70 is coupled to the upper end of the shaft part 61 of the rotating shaft 60 and can rotate integrally with the rotating shaft 60. Accordingly, the rotation of the rotating shaft 60 can be supported by the first bearing 27.
[0123] The bearing support 70 is formed in a hollow cylindrical shape and can be coupled to the outer circumferential surface of the rotating shaft 60 by press fitting. The length of the bearing support 70 can be the same as or similar to the length of the first bearing 27.
[0124] As an example, the bearing support 70 can include a coupling hole 71 and a boss receiving groove 72.
[0125] The coupling hole 71 can be formed at one end of the bearing support 70. The coupling hole 71 is formed to be coupled to the upper end of the shaft part 61 of the rotating shaft 60. The coupling hole 71 can be disposed concentrically with the shaft part 61 of the rotating shaft 60.
[0126] The coupling hole 71 can be formed to have a step. In other words, the coupling hole 71 can include a first coupling hole 711 and a second coupling hole 712 formed concentrically. The second coupling hole 712 is formed at one end of the first coupling hole 711. The diameter of the first coupling hole 711 can be greater than the diameter of the second coupling hole 712. Accordingly, the inner circumferential surface of the first coupling hole 711 and the inner circumferential surface of the second coupling hole 712 can form a step.
[0127] The first coupling hole 711 is formed to have a diameter corresponding to the outer circumferential surface of the upper end of the shaft part 61 of the rotating shaft 60. Accordingly, the upper end of the shaft part 61 of the rotating shaft 60 can be inserted into the coupling hole 71.
[0128] The diameter of the first coupling hole 711 and the diameter of the upper end of the shaft part 61 of the rotating shaft 60 can be defined such that the upper end of the shaft part 61 of the rotating shaft 60 is press-fitted into the first coupling hole 711 of the bearing support 70. Accordingly, the bearing support 70 can be press-fitted to the upper end of the rotating shaft 60.
[0129] The rotating shaft 60 includes a stepped part 63 to which the bearing support 70 is coupled. The stepped part 63 can be provided at the upper end of the shaft part 61 of the rotating shaft 60. Accordingly, the stepped part 63 can be located below the eccentric part 62. The stepped part 63 of the rotating shaft 60 is formed to correspond to the step of the coupling hole 71 of the bearing support 70. The stepped part 63 can be inserted into the second coupling hole 712 of the bearing support 70. The stepped part 63 of the rotating shaft 60 can be formed to be press-fitted into the second coupling hole 712 of the bearing support 70.
[0130] A boss receiving groove 72 can be formed at the other end of the bearing support 70. The boss receiving groove 72 can be formed on the other end of the bearing support 70 with a predetermined depth. The boss receiving groove 72 can be formed so that the boss 53 of the orbiting scroll 50 is inserted into the boss receiving groove 72. The diameter of the boss receiving groove 72 is formed to be greater than the outer diameter of the boss 53 of the orbiting scroll 50.
[0131] Therefore, when the eccentric portion 62 of the rotating shaft 60 is inserted into the boss 53 of the orbiting scroll 50, the boss 53 of the orbiting scroll 50 is accommodated in the boss receiving groove 72 of the bearing support 70. In this case, there is a gap between the outer circumferential surface of the boss 53 and the inner circumferential surface of the boss receiving groove 72. The oil supplied to the boss 53 through the oil passage 66 can be accommodated in the space between the boss 53 and the boss receiving groove 72.
[0132] The boss receiving groove 72 can be formed to have a circular cross-section. The bottom surface of the boss receiving groove 72 can communicate with the coupling hole 71. Therefore, the eccentric portion 62 of the rotating shaft 60 can protrude into the boss receiving groove 72 through the coupling hole 71.
[0133] The boss receiving groove 72 can be formed to be eccentric with respect to the coupling hole 71. In other words, the boss receiving groove 72 can be formed so that the center of the boss receiving groove 72 and the center of the coupling hole 71 are not located on a straight line. When the boss receiving groove 72 is eccentric with respect to the coupling hole 71, the inner circumferential surface of the boss receiving groove 72 is eccentric with respect to the outer circumferential surface of the bearing support 70.
[0134] The inner circumferential surface of the boss receiving groove 72 forms the inner circumferential surface of the bearing support 70. Therefore, the inner circumferential surface of the bearing support 70 can be formed to be eccentric with respect to the outer circumferential surface of the bearing support 70.
[0135] Referring to Figure 3 and Figure 4 , the bearing support 70 is coupled to the upper end of the rotating shaft 60, and the bearing support 70 is inserted into the shaft hole 21 of the main frame 20. At this time, the first bearing 27 is interposed between the outer circumferential surface of the bearing support 70 and the inner circumferential surface of the shaft hole 21 of the main frame 20. Therefore, the rotation of the rotating shaft 60 can be supported by the first bearing 27.
[0136] In addition, the boss 53 of the orbiting scroll 50 is accommodated in the boss receiving groove 72 of the bearing support 70 coupled to the rotating shaft 60. The eccentric portion 62 of the rotating shaft 60 is inserted into the hole 54 of the boss 53 of the orbiting scroll 50. At this time, the second bearing 37 is interposed between the inner circumferential surface of the boss 53 and the eccentric portion 62. Therefore, the rotation of the eccentric portion 62 of the rotating shaft 60 can be supported by the second bearing 37.
[0137] Referring to Figure 3 and Figure 4 The second bearing 37 disposed between the boss 53 and the eccentric portion 62 is positioned inside the boss receiving groove 72 of the bearing support 70. Because the first bearing 27 is disposed on the outer circumferential surface of the bearing support 70, the second bearing 37 is positioned inside the first bearing 27. The lower end of the second bearing 37 can be located below the upper end of the first bearing 27. In other words, at least a portion of the second bearing 37 can overlap the first bearing 27 in the axial direction S. For example, the second bearing 37 can be disposed such that the center LC of the second bearing 37 in the longitudinal direction is located below the upper end of the first bearing 27. As another example, the second bearing 37 can be disposed such that the entire length of the second bearing 37 overlaps the first bearing 27 in the axial direction S.
[0138] Accordingly, the first bearing 27 and the second bearing 37 are arranged to overlap in the axial direction S. In other words, the second bearing 37 is arranged to overlap the first bearing 27 in the radial direction (the direction of the arrow R in FIG. 1) of the main frame 20. Figure 4
[0139] As another example, the boss receiving groove 72 can be formed concentrically with the coupling hole 71. In other words, the boss receiving groove 72 can be formed such that the center of the boss receiving groove 72 and the center of the coupling hole 71 are located on the same axis.
[0140] The bearing support 70 can include an oil hole 73. The oil hole 73 can be formed on the outer circumferential surface of the bearing support 70 to communicate with the boss receiving groove 72. The oil hole 73 can be formed adjacent to the bottom of the boss receiving groove 72.
[0141] Oil that has traveled through the second bearing 37 can be contained in the boss receiving groove 72 of the bearing support 70. The oil contained in the boss receiving groove 72 can be supplied to the first bearing 27 through the oil hole 73.
[0142] As described above, when the bearing support 70 is separated from or separately formed from the rotating shaft 60, external cylindrical grinding can be performed on the eccentric portion 62 of the rotating shaft 60. Accordingly, the surface roughness of the outer circumferential surface of the eccentric portion 62 can be machined to the same surface roughness as the surface roughness of the outer circumferential surface of the bearing support 70.
[0143] As in the prior art, the bearing support can be integrally formed with the rotating shaft to surround the eccentric portion. In this case, the outer circumferential surface of the bearing support is supported by the first bearing 27. The outer circumferential surface of the eccentric portion is supported by the second bearing 37. Accordingly, the bearing support and the eccentric portion need to be formed to have a high surface roughness so that they can be supported by the first bearing 27 and the second bearing 37, respectively.
[0144] Because the outer circumferential surface of the bearing support integrally formed with the rotating shaft is exposed to the outside, the outer circumferential surface of the bearing support can be formed to have a high surface roughness by performing external cylindrical grinding with a grinding wheel.
[0145] However, the eccentric portion is located inside the bearing support. Accordingly, the outer circumferential surface of the eccentric portion cannot be machined by performing external cylindrical grinding with a grinding wheel. A special grinding tool is needed to grind the outer circumferential surface of the eccentric portion. The outer circumferential surface of the eccentric portion cannot be ground with a general grinding wheel.
[0146] Accordingly, in the rotating shaft in which the bearing support is integrally formed according to the prior art, it is difficult to grind the outer circumferential surface of the eccentric portion to have the same surface roughness as the outer circumferential surface of the bearing support.
[0147] However, in the case of the scroll compressor 1 according to one or more embodiments of the present disclosure, the bearing support 70 is separately or individually formed from the rotating shaft 60. Accordingly, in the rotating shaft 60 according to one or more embodiments of the present disclosure, as shown in Figure 8 the outer circumferential surface of the eccentric portion 62 can be ground by external cylindrical grinding using a general grinding wheel.
[0148] Figure 8 is a cross-sectional view illustrating a case in which the eccentric portion 62 of the rotating shaft 60 of the scroll compressor 1 according to one or more embodiments of the present disclosure is ground using a grinding wheel 90.
[0149] As shown in Figure 8 after external cylindrical grinding is performed on the eccentric portion 62 of the rotating shaft 60 using a general grinding wheel 90, the bearing support 70 can be coupled to the upper end of the rotating shaft 60. Accordingly, in the rotating shaft 60 according to one or more embodiments of the present disclosure, the outer circumferential surface of the eccentric portion 62 of the rotating shaft 60 can be ground to have the same surface roughness as the outer circumferential surface of the bearing support 70.
[0150] Accordingly, machining deviation and machining cost of the eccentric portion 62 of the rotating shaft 60 can be reduced. In addition, because the surface roughness of the eccentric portion 62 of the rotating shaft 60 is improved, friction loss of the second bearing 37 can be reduced.
[0151] Also, as described above, when the first bearing 27 disposed in the main frame 20 and the second bearing 37 disposed in the orbiting scroll 50 are arranged to overlap in the axial direction, the distance from the upper end of the orbiting scroll 50 to the center of the first bearing 27 supporting the rotating shaft 60 can be reduced.
[0152] In the case of a scroll compressor according to the related art having a structure in which the first bearing 27 and the second bearing 37 do not overlap in the axial direction, the distance from the upper end of the orbiting scroll 50 to the center of the first bearing 27 supporting the rotating shaft 60 is farther than in the scroll compressor 1 according to one or more embodiments of the present disclosure.
[0153] Accordingly, in the scroll compressor 1 according to one or more embodiments of the present disclosure, when refrigerant is compressed by rotation of the orbiting scroll 50, the moment of force applied to the orbiting scroll 50 centered on the first bearing 27 can be reduced. Then, refrigerant leakage through the gap between the orbiting scroll 50 and the fixed scroll 40 during refrigerant compression can be reduced, thereby improving the compression efficiency of the scroll compressor 1.
[0154] Hereinafter, the scroll compressor 1 according to one or more embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Figures 9 to 12 The compression part of the scroll compressor 1 according to one or more embodiments of the present disclosure will be described in detail.
[0155] Figure 9 FIG. 2 is a partial enlarged sectional view illustrating the compression part of the scroll compressor 1 according to one or more embodiments of the present disclosure. Figure 10 FIG. 3 is an exploded perspective view illustrating main parts of the scroll compressor 1 according to one or more embodiments of the present disclosure. Figure 11 FIG. 4 is a partial enlarged sectional view of part B of FIG. 3. Figure 9 FIG. 5 is a perspective view illustrating a state in which the balance weight 75 of the scroll compressor 1 according to one or more embodiments of the present disclosure is press-fitted into the rotating shaft 60. Figure 12 FIG. 6 is a partial enlarged sectional view of part B of FIG. 5.
[0156] Referring to Figure 9 and Figure 10 , the compression part of the scroll compressor 1 according to one or more embodiments of the present disclosure can include a main frame 20, a fixed scroll 40, an orbiting scroll 50, and a rotating shaft 60.
[0157] Figure 9 and Figure 10 The compression part of the scroll compressor 1 illustrated in Figure 1 and Figure 2 may be disposed inside the housing 10 in the same manner as the compression part of the scroll compressor 1 illustrated in
[0158] The main frame 20, the fixed scroll 40, and the orbiting scroll 50 are the same as those of the scroll compressor 1 according to the above-described embodiment. Therefore, a repeated description is omitted.
[0159] The rotor 82 of the drive motor 80 is fixed to the rotating shaft 60. Therefore, the rotating shaft 60 can be integrally rotated with the rotor 82.
[0160] The rotating shaft 60 can include a shaft portion 61 formed to have a predetermined length and an eccentric portion 62 extending upward from an upper end of the shaft portion 61. The eccentric portion 62 can be integrally formed with the shaft portion 61. A central axis CA2 of the eccentric portion 62 is spaced apart from a center of rotation (i.e., a central axis CA1 of the shaft portion 61) of the rotating shaft 60 by a predetermined distance.
[0161] The rotor 82 of the drive motor 80 can be fixed to the shaft portion 61 of the rotating shaft 60. One end of the shaft portion 61 is inserted into the shaft hole 21 of the main frame 20 and can be rotatably supported by the first bearing 27 provided in the shaft hole 21.
[0162] The eccentric portion 62 formed at the upper end of the rotating shaft 60 can be inserted into the hole 54 of the boss 53 of the orbiting scroll 50. The eccentric portion 62 of the rotating shaft 60 can be supported by the second bearing 37 provided in the boss 53 of the orbiting scroll 50.
[0163] The bearing support 70 can be provided at the upper end of the rotating shaft 60 (i.e., the upper end of the shaft portion 61). The bearing support 70 is provided on the rotating shaft 60 to surround the eccentric portion 62. The bearing support 70 can be rotatably supported by the first bearing 27 provided on the main frame 20. That is, the first bearing 27 is interposed between the bearing support 70 and the main frame 20 and can support the rotation of the bearing support 70 coupled to the rotating shaft 60. Therefore, the rotating shaft 60 can be rotatably supported by the first bearing 27.
[0164] The balance weight 75 can be formed below the bearing support 70. The balance weight 75 can be integrally formed with the bearing support 70. The balance weight 75 can be formed to extend from a lower end of the bearing support 70.
[0165] The balance weight 75 can be provided on the shaft portion 61 of the rotating shaft 60 to be positioned between the main frame 20 and the rotor 82. The balance weight 75 can be formed not to interfere with the main frame 20 when the rotating shaft 60 is rotated.
[0166] The counterweight 75 can include a fixing hole 751. The counterweight 75 can be fixed to the rotating shaft 60 by inserting the rotating shaft 60 into the fixing hole 751. The counterweight 75 can be fixed to the rotating shaft 60 by press fitting. The diameter of the fixing hole 751 of the counterweight 75 and the diameter of the portion of the rotating shaft 60 on which the counterweight 75 is disposed can be defined such that the rotating shaft 60 is press fitted into the fixing hole 751 of the counterweight 75.
[0167] As an example, the counterweight 75 can be formed such that the rotating shaft 60 is press fitted into the entire length of the fixing hole 751 of the counterweight 75.
[0168] As an example, as shown in Figure 11 , the diameter of a portion 751a of the fixing hole 751 of the counterweight 75 in the longitudinal direction can be defined such that the rotating shaft 60 is press fitted into the portion 751a, and the diameter of the remaining portion 751b of the fixing hole 751 can be defined such that there is a gap between the rotating shaft 60 and the fixing hole 751.
[0169] The bearing support 70 and the counterweight 75, which are integrally formed, are disposed to offset the unbalance caused by the eccentric rotation of the orbiting scroll 50.
[0170] Referring to Figure 9 , Figure 10 and Figure 12 , the bearing support 70 can be integrally formed with the counterweight 75. The integral bearing support 70 and counterweight 75 are separately or individually formed from the rotating shaft 60, and the integral bearing support 70 and counterweight 75 can be coupled to the outer circumferential surface of the rotating shaft 60. The bearing support 70 is fixed to the rotating shaft 60 when the counterweight 75 is coupled to the rotating shaft 60. The bearing support 70 fixed to the rotating shaft 60 can integrally rotate with the rotating shaft 60.
[0171] The bearing support 70 can be formed in a hollow cylindrical shape. The hollow portion of the bearing support 70 can be formed eccentric with respect to the outer circumferential surface. In other words, the inner circumferential surface of the bearing support 70 is formed eccentric with respect to the outer circumferential surface of the bearing support 70. That is, the bearing support 70 can be formed such that the center of the inner circumferential surface of the bearing support 70 is eccentric with respect to the center of the outer circumferential surface of the bearing support 70.
[0172] As another embodiment, the bearing support 70 can be formed such that the inner circumferential surface and the outer circumferential surface of the bearing support 70 are concentric. That is, the bearing support 70 can be formed such that the center of the inner circumferential surface of the bearing support 70 coincides with the center of the outer circumferential surface of the bearing support 70.
[0173] As Figure 9 shown, when the hollow portion of the bearing support 70 is eccentrically formed, the bearing support 70 can serve as a sub counterweight to offset the unbalance of the orbiting scroll 50 together with the counterweight 75. When the hollow portion of the bearing support 70 is concentrically formed with the outer circumferential surface, the bearing support 70 does not serve as a sub counterweight.
[0174] The bearing support 70 is formed to support the first bearing 27. When the bearing support 70 is fixed to the rotating shaft 60 through the counterweight 75, the bearing support 70 can support the first bearing 27. That is, the outer circumferential surface of the bearing support 70 fixed to the rotating shaft 60 can support the inner circumferential surface of the first bearing 27. Accordingly, the rotating shaft 60 can be rotatably supported by the first bearing 27.
[0175] Since the first bearing 27 is fixed to the shaft hole 21 of the main frame 20, the bearing support 70 can rotate with respect to the first bearing 27. The bearing support 70 is integrally formed with the counterweight 75, and the counterweight 75 integrally rotates with the rotating shaft 60, and thus the rotation of the rotating shaft 60 can be supported by the first bearing 27.
[0176] The hollow portion of the bearing support 70 can form a boss receiving groove 72.
[0177] The boss receiving groove 72 can be formed at one end of the bearing support 70. The boss receiving groove 72 can be formed on one end of the bearing support 70 at a predetermined depth. The boss receiving groove 72 can be formed so that the boss 53 of the orbiting scroll 50 is inserted into the boss receiving groove 72.
[0178] The diameter of the boss receiving groove 72 is formed to be greater than the outer diameter of the boss 53 of the orbiting scroll 50. Accordingly, when the eccentric portion 62 of the rotating shaft 60 is inserted into the boss 53 of the orbiting scroll 50, the boss 53 of the orbiting scroll 50 is accommodated in the boss receiving groove 72 of the bearing support 70. In this case, there is a gap between the outer circumferential surface of the boss 53 and the inner circumferential surface of the boss receiving groove 72. The oil supplied to the boss 53 through the oil passage 66 can be accommodated in the space between the boss 53 and the boss receiving groove 72.
[0179] The boss receiving groove 72 can be formed to have a circular cross-section. The bottom surface of the boss receiving groove 72 can communicate with the fixing hole 751 of the counterweight 75. Accordingly, the eccentric portion 62 of the rotating shaft 60 can protrude into the boss receiving groove 72 through the fixing hole 751 of the counterweight 75.
[0180] The boss receiving groove 72 can be formed eccentric with respect to the fixing hole 751. In other words, the boss receiving groove 72 of the bearing support 70 can be formed such that the center of the boss receiving groove 72 is not on the same line as the center of the fixing hole 751 of the counterweight 75. When the boss receiving groove 72 is eccentric with respect to the fixing hole 751, the inner circumferential surface of the boss receiving groove 72 is eccentric with respect to the outer circumferential surface of the bearing support 70.
[0181] The inner circumferential surface of the boss receiving groove 72 forms the inner circumferential surface of the bearing support 70. Thus, the inner circumferential surface of the bearing support 70 can be formed eccentric with respect to the outer circumferential surface of the bearing support 70.
[0182] In addition, an oil passage 66 can be formed in the rotating shaft 60 to pass through the shaft portion 61 and the eccentric portion 62. An outlet 66a of the oil passage 66 is provided at the upper end of the eccentric portion 62.
[0183] Reference Figure 9 The bearing support 70 is coupled to the upper end of the rotating shaft 60 by the counterweight 75, and the bearing support 70 is inserted into the shaft hole 21 of the main frame 20. At this time, the first bearing 27 is interposed between the outer circumferential surface of the bearing support 70 and the inner circumferential surface of the shaft hole 21 of the main frame 20. Thus, the rotation of the rotating shaft 60 can be supported by the first bearing 27.
[0184] Further, the boss 53 of the orbiting scroll 50 is accommodated in the boss receiving groove 72 of the bearing support 70 coupled to the rotating shaft 60. The eccentric portion 62 of the rotating shaft 60 is inserted into the hole 54 of the boss 53 of the orbiting scroll 50. At this time, the second bearing 37 is interposed between the inner circumferential surface of the boss 53 and the eccentric portion 62. Thus, the rotation of the eccentric portion 62 of the rotating shaft 60 can be supported by the second bearing 37.
[0185] The second bearing 37 disposed between the boss 53 and the eccentric portion 62 is inside the boss receiving groove 72 of the bearing support 70. Since the first bearing 27 is disposed on the outer circumferential surface of the bearing support 70, the second bearing 37 is inside the first bearing 27. The lower end of the second bearing 37 can be below the upper end of the first bearing 27. At least a portion of the second bearing 37 can overlap the first bearing 27 in the axial direction (direction S of the arrow in FIG. 10). Figure 9 For example, the second bearing 37 can be disposed such that the center LC of the second bearing 37 in the longitudinal direction is below the upper end of the first bearing. As another example, the second bearing 37 can be disposed such that the entire length of the second bearing 37 overlaps the first bearing 27 in the axial direction S.
[0186] Thus, the first bearing 27 and the second bearing 37 are arranged to overlap in the axial direction S.
[0187] The bearing support 70 can include an oil hole 73. The oil hole 73 can be formed on the outer circumferential surface of the bearing support 70 to communicate with the boss receiving groove 72. The oil hole 73 can be formed adjacent to the bottom of the boss receiving groove 72.
[0188] Oil that has traveled through the second bearing 37 can be contained in the boss receiving groove 72 of the bearing support 70. The oil contained in the boss receiving groove 72 can be supplied to the first bearing 27 through the oil hole 73.
[0189] As described above, when the balance weight 75 including the bearing support 70 is separated from or separately formed from the rotating shaft 60, external cylindrical grinding can be performed on the eccentric portion 62 of the rotating shaft 60 before the balance weight 75 including the bearing support 70 is coupled to the rotating shaft 60. Accordingly, the surface roughness of the outer circumferential surface of the eccentric portion 62 can be machined to be the same surface roughness as the surface roughness of the outer circumferential surface of the bearing support 70.
[0190] As a result, the machining deviation and machining cost of the eccentric portion 62 of the rotating shaft 60 can be reduced. In addition, since the surface roughness of the eccentric portion 62 of the rotating shaft 60 is improved, the friction loss of the second bearing 37 can be reduced.
[0191] Further, when the bearing support 70 and the balance weight 75 are integrally formed as described above, the bearing support 70 can be disposed on the rotating shaft 60 by simply coupling the balance weight 75 to the rotating shaft 60. Accordingly, the manufacturing cost of the scroll compressor 1 can be reduced.
[0192] While the disclosure has been shown and described with reference to various exemplary embodiments thereof, it will be understood that the various exemplary embodiments are intended to be illustrative only and are not limiting. Those skilled in the art will understand that various changes in form and details can be made without departing from the true spirit and full scope of the disclosure, including the appended claims and their equivalents.
Claims
1. A scroll compressor comprising: a main frame including a shaft hole; a fixed scroll disposed on an upper side of the main frame; a moving scroll disposed in a space formed by the fixed scroll and the main frame, a lower surface of the moving scroll including a boss inserted into the shaft hole of the main frame; a rotatable shaft including an eccentric portion inserted into the boss of the moving scroll and inserted into the shaft hole of the main frame; a first bearing disposed in the shaft hole between the shaft hole of the main frame and a bearing support coupled to an outer circumferential surface of the rotatable shaft; and a second bearing disposed between the boss of the moving scroll and the eccentric portion of the rotatable shaft, wherein a position of the second bearing overlaps with the first bearing in an axial direction of the rotatable shaft, and wherein an inner circumferential surface of the first bearing is supported by an outer circumferential surface of the bearing support, and the bearing support is separable from and couplable to the rotatable shaft. 2.The scroll compressor of claim 1, wherein the bearing support has a hollow cylindrical shape, and is press-fitted to an outer circumferential surface of an upper end of the rotatable shaft. 3.The scroll compressor of claim 2, wherein the upper end of the rotatable shaft includes a stepped portion below the eccentric portion, and the bearing support is coupled to the stepped portion. 4.The scroll compressor of claim 2, wherein an inner circumferential surface of the bearing support is eccentric with respect to an outer circumferential surface of the bearing support. 5.The scroll compressor of claim 1, further comprising: a balance weight disposed on the rotatable shaft, wherein the bearing support integrally extends upward from the balance weight in the axial direction of the rotatable shaft. 6.The scroll compressor of claim 5, wherein the rotatable shaft is press-fitted into a fixing hole of the balance weight such that the rotatable shaft is coupled to the balance weight. 7.The scroll compressor of claim 1, wherein the bearing support includes an oil hole. 8.The scroll compressor of claim 1, wherein the first bearing and the second bearing are oil-free bearings. 9.The scroll compressor of claim 1, wherein an outer circumferential surface of the first bearing is fixed to the shaft hole of the main frame, and an inner circumferential surface of the first bearing supports an outer circumferential surface of the bearing support in a manner that the bearing support is rotatable. 10.The scroll compressor of claim 1, wherein an outer circumferential surface of the second bearing is fixed to an inner circumferential surface of the boss of the moving scroll, and an inner circumferential surface of the second bearing supports an outer circumferential surface of the eccentric portion of the rotatable shaft in a manner that the eccentric portion is rotatable. 11.A scroll compressor comprising: a main frame including a shaft hole; a fixed scroll disposed on an upper side of the main frame; a movable scroll disposed in a space formed by the fixed scroll and the main frame, a lower surface of the movable scroll including a boss inserted into the shaft hole of the main frame; a rotatable shaft including an eccentric portion inserted into the boss of the movable scroll and inserted into the shaft hole of the main frame; a first bearing disposed in the shaft hole between the shaft hole of the main frame and the rotatable shaft; a second bearing disposed between the boss of the movable scroll and the eccentric portion of the rotatable shaft; and a bearing support having a hollow cylindrical shape, the bearing support being separable from and couplable to an outer circumferential surface of an upper end of the rotatable shaft to support an inner circumferential surface of the first bearing, wherein a portion of the second bearing is located in a hollow portion of the bearing support.
12. The scroll compressor of claim 11, wherein a lower end of the second bearing is located below an upper end of the first bearing in an axial direction of the rotatable shaft.
13. The scroll compressor of claim 11, wherein the bearing support is press-fitted to the outer circumferential surface of the upper end of the rotatable shaft.
14. The scroll compressor of claim 11, further comprising: a balance weight disposed on the rotatable shaft below the main frame, wherein the bearing support integrally extends upward from the balance weight in an axial direction of the rotatable shaft.
15. The scroll compressor of claim 14, wherein the balance weight includes a fixed hole eccentric with respect to the hollow portion of the bearing support, and the rotatable shaft is press-fitted into the fixed hole of the balance weight such that the rotatable shaft is coupled with the balance weight.