Scroll compressor

Abstract

A scroll compressor is provided. The scroll compressor may comprise a casing, a driving motor, a fixed scroll, an orbiting scroll, a rotary shaft, and a bush bearing. A tilting avoidance portion may be formed on the inner circumferential surface of the bush bearing to avoid contact with the rotary shaft. Accordingly, the outer diameter of the rotary shaft is expanded to the outer diameter of the bush bearing such that, while maintaining the compression length, the surface pressure between the rotary shaft and the fixed scroll can be reduced. In addition, the bush bearing can be prevented from being tilted together with the rotary shaft, thereby reducing friction loss between the bush bearing and the fixed scroll.

Description

scroll compressor

[0001] The present invention relates to a through-pipe scroll compressor.

[0002] Scroll compressors can be categorized as upper compression or lower compression types based on the location of the drive motor and compression unit, which form the drive or transmission unit. Upper compression types have the compression unit positioned above the drive motor, while lower compression types have the compression unit positioned below the drive motor. This classification is based on examples where the casing is installed vertically or horizontally. When the casing is installed horizontally, the left side can be conveniently designated as the upper side and the right side as the lower side.

[0003] Scroll compressors can be classified into back-mounted and shaft-through types depending on how the rotating shaft is coupled to the orbiting scroll. In the back-mounted type, the rotating shaft is coupled to the back of the orbiting scroll, while in the shaft-through type, the rotating shaft is coupled by penetrating the orbiting scroll.

[0004] In the back-to-back coupling method, the orbiting wrap and fixed wrap are extended long to the center of the orbiting scroll and fixed scroll, but the gap between the point of application of the gas reaction force and the support point of the bearing is large, which may cause the behavior of the orbiting scroll to become unstable.

[0005] The shaft-through method minimizes the gap between the point of application of the gas reaction force and the support point of the bearing, thereby stabilizing the behavior of the orbiting scroll. In addition, since the rotating shaft penetrates the orbiting scroll and is rotatably connected to the fixed scroll, the length of the orbiting wrap and the fixed wrap can be shortened, thereby reducing the compression length.

[0006] Patent Document 1 (Korean Patent Publication No. 10-2019-0011115, published on February 1, 2019) discloses a through-axis scroll compressor. In Patent Document 1, a rotating shaft sequentially penetrates a main frame, an orbiting scroll, and a fixed scroll, thereby being connected thereto. In other words, the rotating shaft of Patent Document 1 is provided with an eccentric member that eccentrically penetrates the orbiting scroll and is rotatably connected to the main frame and the fixed scroll, respectively.

[0007] However, in the conventional shaft-through scroll compressor as described above, the surface pressure between the sub-bearing surface of the rotating shaft coupled to the fixed scroll and the sub-bearing of the fixed scroll into which the sub-bearing surface is inserted may increase. In other words, since the rotating shaft eccentrically penetrates the orbiting scroll and is rotatably coupled to the fixed scroll, the outer diameter of the sub-bearing surface is formed to be smaller than the outer diameter of the eccentric portion, which ultimately increases the surface pressure between the sub-bearing surface and the sub-bearing. In consideration of this, when the outer diameter of the sub-bearing surface is enlarged, the outer diameter of the eccentric portion is also enlarged, which may reduce the compression length or increase the outer diameter of the compression portion.

[0008] In addition, when the axial length of the sub-bearing surface and the fixed bearing is formed long, the surface pressure can be relatively reduced, but wear between the sub-bearing surface and the fixed bearing can increase when the rotation axis is tilted.

[0009] The purpose of the present invention is to provide a scroll compressor capable of lowering the surface pressure between a rotating shaft and a bearing supporting the shaft in the radial direction while maintaining the compression length.

[0010] Another object of the present invention is to provide a scroll compressor capable of suppressing wear due to tilting of the rotating shaft while lowering the surface pressure between the rotating shaft and the bearing.

[0011] Another object of the present invention is to provide a scroll compressor that can increase reliability while suppressing wear caused by tilting of a rotating shaft.

[0012] Another object of the present invention is to provide a scroll compressor that suppresses wear caused by tilting of the rotating shaft while allowing oil to be smoothly supplied between the rotating shaft and the bearing.

[0013] In order to achieve the object of the present invention, a scroll compressor including a casing, a driving motor, a fixed scroll, an orbiting scroll, a rotating shaft, and a bushing bearing may be provided. The driving motor may be provided inside the casing. The fixed scroll may be fixed to the casing at one side of the driving motor. The orbiting scroll may form a compression chamber between the fixed scroll and the fixed scroll while performing an orbital motion with respect to the fixed scroll. The rotating shaft may have one end coupled to the rotor of the driving motor, and the other end may eccentrically penetrate the orbiting scroll and be rotatably coupled to the fixed scroll. The bushing bearing may be coupled to the rotating shaft and provided between the fixed scroll and the rotating shaft. The bushing bearing may have a tilting avoidance formed on an inner circumferential surface facing an outer circumferential surface of the rotating shaft to avoid contact with the rotating shaft. This allows the outer diameter of the rotating shaft to be expanded to match the outer diameter of the bushing bearing, thereby maintaining the compression length while reducing the surface pressure between the rotating shaft and the fixed scroll. Furthermore, by suppressing the bushing bearing from tilting along with the rotating shaft, the frictional loss between the bushing bearing and the fixed scroll can be reduced.

[0014] For example, the tilting avoidance member may be formed so that the inner diameter of the first stage adjacent to the driving motor is larger than the inner diameter of the second stage distant from the driving motor. Through this, the axial support force acting on the inner surface of the bushing bearing and the bearing reaction force acting on the outer surface of the bushing bearing are formed on the same radius and / or close to each other, thereby suppressing the bushing bearing from tilting when the rotation shaft is tilted.

[0015] For example, the tilt avoidance section may be formed as a tapered inclined surface at least partially between the first end and the second end. This allows the gap between the outer surface of the rotational shaft and the inner surface of the bushing bearing to increase as it goes toward the end of the bushing bearing, thereby effectively suppressing tilting of the bushing bearing when the rotational shaft tilts.

[0016] In addition, the tilting avoidance portion may be formed with at least one step surface between the first stage and the second stage. Through this, the tilting avoidance portion can be easily processed by minimizing the slope processing in the tilting avoidance portion as much as possible.

[0017] In another embodiment, the tilting avoidance portion may include a first avoidance portion adjacent to the driving motor; and a second avoidance portion located further from the driving motor than the first avoidance portion. The second avoidance portion may be formed to be inclined at a preset angle with respect to a cross-section of the first avoidance portion. Through this, the gap between the bushing bearing and the rotational shaft increases as it moves toward the end of the bushing bearing, thereby suppressing the bushing bearing from tilting together when the rotational shaft is tilted.

[0018] For example, the axial length of the tilting avoidance portion may be formed to be less than or equal to half the axial length of the bushing bearing. The axial length of the second avoidance portion may be formed to be greater than or equal to the axial length of the first avoidance portion. Through this, the inclined processing area of ​​the tilting avoidance portion can be reduced, making it easy to process the entire tilting avoidance portion, while at the same time securing the strength of the tilting avoidance portion, thereby increasing the reliability of the bushing bearing.

[0019] Specifically, the first skin portion may be formed so that its inner diameter is the same along the axial direction of the rotation axis. This allows the first skin portion, which forms part of the tilting skin portion, to be easily processed.

[0020] In addition, a third skin portion may be further included between the first skin portion and the second skin portion. The radial width of the third skin portion may be formed to be smaller than or equal to the radial width of the second skin portion. Through this, the thickness of the first skin portion can be sufficiently secured under the condition that the radial width of the second skin portion is the same, thereby suppressing damage to the first skin portion due to collision with the rotating shaft and / or the fixed scroll.

[0021] Specifically, the third skin portion may be formed parallel to the cross-section of the first skin portion or may be formed at an inclination angle smaller than the inclination angle of the second skin portion. Through this, the axial length of the second skin portion may be formed as long as possible to enhance the tilting avoidance effect.

[0022] As another example, an oil passage may be formed inside the rotating shaft, and an oil hole may be formed that penetrates from the inner surface of the oil passage to the outer surface of the rotating shaft. The bush bearing may have an oil supply hole that penetrates from the inner surface to the outer surface. Through this, oil can be smoothly supplied between the outer surface of the bush bearing and the sub-bearing of the fixed scroll facing it through the oil supply hole.

[0023] For example, the above-described oiling hole may be formed so as to radially overlap at least a portion of the above-described oiling hole. This minimizes the gap between the oiling holes and the oiling hole, thereby allowing oil passing through the oiling hole to move more quickly to the oiling hole.

[0024] Additionally, the fueling hole can be spaced apart from the tilting avoidance part in the axial direction by a preset distance. This allows for securing an appropriate sealing area between the tilting avoidance part and the fueling hole.

[0025] Specifically, a sealing surface may be formed around the oil supply hole. The width of the sealing surface may be formed to be greater than or equal to the radius of the oil supply hole. This prevents high-pressure refrigerant from flowing into the gap between the inner surface of the bushing bearing and the outer surface of the rotating shaft facing it.

[0026] In addition, an oil supply groove extending along the axial direction may be formed on the outer surface of the bush bearing. The oil supply groove may be formed to be in communication with the oil supply hole. Accordingly, oil moving to the outer surface of the bush bearing through the oil supply hole can move along the oil supply groove along the axial direction of the bush bearing, thereby evenly lubricating the bush bearing and the sub-bearing facing it.

[0027] Specifically, a communication groove may be formed in a recessed manner at one end of the above-described lubrication groove to connect the inner surface of the bushing bearing and the lubrication groove. This allows a portion of the oil moving axially through the lubrication groove to quickly flow into the tilting avoidance portion through the communication groove, thereby forming a tight seal between the rotating shaft and the bushing bearing.

[0028] The scroll compressor of the present invention comprises a bushing bearing between a rotating shaft and a fixed scroll, wherein a tilting avoidance portion may be formed on the inner surface of the bushing bearing to avoid contact with the rotating shaft. This allows the outer diameter of the rotating shaft to be expanded to the outer diameter of the bushing bearing, thereby maintaining the compression length while reducing the surface pressure between the rotating shaft and the fixed scroll. In addition, the bushing bearing is prevented from tilting together with the rotating shaft, thereby reducing frictional loss between the bushing bearing and the fixed scroll.

[0029] In the scroll compressor of the present invention, the tilting avoidance part can be formed so that the inner diameter of the first stage adjacent to the driving motor is larger than the inner diameter of the second stage distant from the driving motor. Through this, the shaft support force acting on the inner surface of the bush bearing and the bearing reaction force acting on the outer surface of the bush bearing are formed on the same radius and / or close to each other, so that the bush bearing can be prevented from tilting when the rotating shaft is tilted.

[0030] The scroll compressor of the present invention comprises a first avoidance portion adjacent to a driving motor, and a second avoidance portion located further from the driving motor than the first avoidance portion, wherein the second avoidance portion can be formed to be inclined at a preset angle with respect to a cross-section of the first avoidance portion. Through this, the gap between the bush bearing and the rotation shaft increases as it goes toward the end of the bush bearing, thereby suppressing the bush bearing from tilting together when the rotation shaft is tilted.

[0031] The scroll compressor of the present invention may have an oil supply hole formed through the inner surface of the bushing bearing to the outer surface thereof. This allows oil to be smoothly supplied between the outer surface of the bushing bearing and the sub-bearing of the fixed scroll facing it through the oil supply hole.

[0032] Fig. 1 is a cross-sectional view showing a scroll compressor according to the present embodiment.

[0033] Fig. 2 is a perspective view showing the rotating shaft and the fixed scroll separated from the scroll compressor according to the present embodiment.

[0034] Figure 3 is a perspective view showing the rotating shaft and bushing bearing in Figure 2 separated.

[0035] Figure 4 is a cross-sectional view taken along line “Ⅸ-Ⅸ” of Figure 3.

[0036] Fig. 5 is a cross-sectional view showing the assembly of the rotary shaft and fixed scroll in Fig. 2.

[0037] Fig. 6 is a schematic diagram illustrating the operational effect of a bushing bearing equipped with a tilting avoidance part according to the present embodiment.

[0038] Fig. 7 is a perspective view showing another embodiment of a bushing bearing.

[0039] Figure 8 is a cross-sectional view of the bushing bearing coupled to the rotating shaft in Figure 7.

[0040] Fig. 9 is a perspective view showing another embodiment of a rotating shaft and a bushing bearing.

[0041] Fig. 10 is a cross-sectional view of the bushing bearing coupled to the rotating shaft in Fig. 9.

[0042] Hereinafter, a scroll compressor according to the present invention will be described in detail with reference to the attached drawings. In the following description, descriptions of some components may be omitted to clarify the features of the present invention.

[0043] In addition, the term "upper side" used in the following description means the direction away from the support surface supporting the scroll compressor according to the embodiment of the present invention, that is, the upper side toward the drive unit (power unit or drive motor) when looking at the drive unit (power unit or drive motor) and the compression unit in the center. The term "lower side" means the direction approaching the support surface, that is, the lower side toward the compression unit when looking at the drive unit (power unit or drive motor) and the compression unit in the center.

[0044] Additionally, the term "axial" used in the following description refers to the longitudinal direction of the axis of rotation. "Axial" can be understood as the vertical direction. "Radial" refers to the direction intersecting the axis of rotation.

[0045] In addition, in the following description, the scroll compressor is described as a sealed scroll compressor in which the drive unit (electric unit or drive motor) and the compression unit are provided in the casing. However, the same can be applied to an open compressor in which the drive unit (electric unit or drive motor) is provided outside the casing and connected to the compression unit provided inside the casing.

[0046] In addition, the following description will be given as an example a lower compression type scroll compressor in which the drive unit and the compression unit are arranged in the vertical axial direction and the compression unit is located lower than the drive unit (the drive unit or the drive motor). However, the same can be applied to a horizontal scroll compressor in which the drive unit (the drive unit or the drive motor) and the compression unit are arranged left and right, as well as an upper compression type scroll compressor in which the compression unit is located higher than the drive unit (the drive unit or the drive motor).

[0047] In addition, the following description takes as an example a high-pressure scroll compressor that is a lower compression type and in which a refrigerant suction pipe forming a suction passage is directly connected to a compression section and a refrigerant discharge pipe is connected to the internal space of the casing so that the internal space of the casing forms a discharge pressure.

[0048] Fig. 1 is a cross-sectional view showing a scroll compressor according to the present embodiment.

[0049] Referring to FIG. 1, a high-pressure, bottom-compression scroll compressor (hereinafter, abbreviated as a scroll compressor) according to the present embodiment is provided with a drive motor (120) forming an electric part in the upper half of a casing (110), and a main frame (130), an orbiting scroll (140), a fixed scroll (150), and a discharge cover (160) are provided on the lower side of the drive motor (120). Typically, the drive motor (120) forms an electric part as described above, and the main frame (130), the orbiting scroll (140), the fixed scroll (150), and the discharge cover (160) form a compression part (C).

[0050] The drive motor (120) forming the electric part is coupled to the upper end of the rotation shaft (125) to be described later, and the compression part (C) is coupled to the lower end of the rotation shaft (125). Accordingly, the compressor forms the lower compression structure described above, and the compression part (C) is connected to the drive motor (120) by the rotation shaft (125) and operates by the rotational force of the drive motor (120). Therefore, the drive motor (120) can be understood as a drive part that drives the compression part (C), and thus, in the following description, the drive motor can be used interchangeably as the electric part or the drive part.

[0051] Referring to FIG. 1, the casing (110) according to the present embodiment may include a cylindrical shell (111), an upper shell (112), and a lower shell (113). The cylindrical shell (111) has a cylindrical shape with both upper and lower ends open, the upper shell (112) is coupled to cover the opened upper end of the cylindrical shell (111), and the lower shell (113) is coupled to cover the opened lower end of the cylindrical shell (111). Accordingly, the internal space (not shown) of the casing (110) is sealed, and the sealed internal space of the casing (110) is divided into a lower space (S1) and an upper space (S2) based on the driving motor (120).

[0052] The lower space (S1) is a space formed on the lower side of the driving motor (120), and the lower space (S1) can be divided into a storage space (S11) and a discharge space (S12) based on the compression section (C).

[0053] The upper space (S2) is a space formed above the driving motor (120) and forms an oil separation space where oil is separated from the refrigerant discharged from the compression unit (C). A refrigerant discharge pipe (116), which will be described later, is connected to the upper space (S2).

[0054] The aforementioned driving motor (120) and main frame (130) are inserted and fixed inside the cylindrical shell (111). An oil recovery passage (not shown) may be formed on the outer surface of the driving motor (120) and the outer surface of the main frame (130) at a predetermined interval from the inner surface of the cylindrical shell (111).

[0055] A refrigerant suction pipe (115) is connected by penetrating the side of the cylindrical shell (111). Accordingly, the refrigerant suction pipe (115) is connected by penetrating the cylindrical shell (111) forming the casing (110) in the radial direction.

[0056] The upper part of the upper shell (112) is connected to the inner space (not shown) of the casing (110), specifically, the upper space (S2) formed on the upper side of the driving motor (120), through which the inner end of the refrigerant discharge pipe (116) is connected.

[0057] One end of an oil circulation pipe (not shown) may be radially connected to the lower half of the lower shell (113). The oil circulation pipe is open at both ends, and the other end of the oil circulation pipe may be connected to the refrigerant suction pipe (115). An oil circulation valve (not shown) may be installed in the middle of the oil circulation pipe.

[0058] Referring to Fig. 1, the driving motor (120) according to the present embodiment includes a stator (121) and a rotor (122). The stator (121) is inserted and fixed into the inner surface of the cylindrical shell (111), and the rotor (122) is rotatably provided inside the stator (121).

[0059] The stator (121) includes a stator core (1211) and a stator coil (1212).

[0060] The stator core (1211) is formed in a circular or hollow cylindrical shape and is fixed to the inner surface of the cylindrical shell (111) by hot pressing.

[0061] The stator coil (1212) is wound around the stator core (1211) and is electrically connected to an external power source through a power cable (not shown) that penetrates the casing (110).

[0062] The rotor (122) includes a rotor core (1221) and a permanent magnet (1222).

[0063] The rotor core (1221) is rotatably inserted into the stator core (1211) at a predetermined gap (not shown). Permanent magnets (1222) are embedded in the rotor core (1221) at a predetermined gap along the circumference.

[0064] A rotation shaft (125) is coupled to the center of the rotor core (1221). The upper part of the rotation shaft (125) is press-fitted and coupled to the rotor (122), and the lower part of the rotation shaft (125) is rotatably inserted into the main frame (130) and supported in the radial direction.

[0065] The rotary shaft (125) transmits the rotational force of the driving motor (120) to the orbiting scroll (140) forming the compression section (C). Accordingly, the orbiting scroll (140) eccentrically coupled to the rotary shaft (125) rotates relative to the fixed scroll (150).

[0066] For example, the rotation shaft (125) may be composed of a main shaft portion (1251), a main bearing surface portion (1252), an eccentric portion (1253), and a sub-bearing surface portion (1254). The main shaft portion (1251) is a portion coupled to the rotor (122), the main bearing surface portion (1252) is a portion supported radially by a main frame (130) to be described later, the eccentric portion (1253) is a portion eccentrically coupled to a rotating scroll (140) to be described later, and the sub-bearing surface portion (1254) is a portion supported radially by a fixed scroll (150) to be described later. In other words, the rotating shaft (125) has a main shaft portion (1251) forming one end coupled to the rotor (122), and the main bearing surface portion (1252), the eccentric portion (1253), and the western bearing surface portion (1254) forming the other end can be coupled by penetrating the main frame (130), the orbiting scroll (140), and the fixed scroll (150), respectively.

[0067] The main shaft portion (1251), the main bearing surface portion (1252), and the sub-bearing surface portion (1254) are formed on the shaft center line (CL), and the eccentric portion (1253) can be formed eccentrically with respect to the shaft center line (CL). For example, when the shaft center line (CL) is used as a reference, the outer diameter of the eccentric portion (1253) can be formed to be smaller than or equal to the outer diameter of the main bearing surface portion (1252). In other words, the outer diameter of the eccentric portion (1253) can be formed to be smaller than the outer diameter of the main bearing surface portion (1252) so that the outer surface of the eccentric portion (1253) does not protrude beyond the outer surface of the main bearing surface portion (1252). Accordingly, even if the main frame (130) is inserted from the other end of the rotating shaft (125) during assembly of the compressor, the bearing gap between the main frame (e.g., the main shaft hole described later) (130) and the main bearing surface (1252) can be maintained.

[0068] In this case, the outer diameter of the sub-bearing surface portion (1254) may be formed to be smaller than the outer diameter of the main bearing surface portion (1252), for example, the outer diameter of the sub-bearing surface portion (1254) may be formed to be smaller than or equal to the outer diameter of the eccentric portion (1253) based on the shaft center line (CL). In other words, the outer diameter of the sub-bearing surface portion (1254) may be formed to be smaller than the outer diameter of the eccentric portion (1253) so that the outer surface of the sub-bearing surface portion (1254) does not protrude beyond the outer surface of the eccentric portion (1253). Accordingly, even if the orbiting scroll (140) is inserted from the other end of the rotating shaft (125) during assembly of the compressor, the bearing gap between the orbiting scroll (e.g., the rotating shaft coupling portion to be described later) (140) and the eccentric portion (1253) can be maintained.

[0069] However, since the outer diameter of the sub-bearing surface portion (1254) is formed smaller than the outer diameter of the eccentric portion (1253), the surface pressure may increase significantly on the bearing surface between the sub-bearing surface portion (1254) and the sub-bearing (1532) to be described later, which faces it in the radial direction. Accordingly, a bushing bearing (180), which forms a part of the sub-bearing surface portion (1254), may be inserted between the sub-bearing surface portion (1254) and the sub-bearing (1532). For example, the bushing bearing (180) may be press-fitted onto the outer circumferential surface of the sub-bearing surface portion (1254) or may be fixedly connected using a separate fixing member. Accordingly, the actual outer diameter of the sub-bearing surface portion (1254) increases, so that the surface pressure between the sub-bearing surface portion (or bushing bearing) (1254) and the sub-bearing (1532) may be reduced. Bushing bearings (180) will be explained again later along with sub-bearings.

[0070] In addition, an oil passage (126) is formed in an axial or inclined direction inside the rotating shaft (125) to guide the oil stored in the oil storage space (S11) of the casing (110) to the compression chamber (V) and / or the bearing surface, and an oil hole (1261) may be formed in the middle of the oil passage (126) so that the oil sucked through the oil passage (126) is supplied to each bearing surface. For example, the oil holes (1261) may be formed on both axial sides of the eccentric portion (1253), and may be formed to be received in oil receiving grooves (1255) formed annularly on both axial sides of the eccentric portion (1253).

[0071] In addition, an oil pickup (127) for pumping oil filled in the oil storage space (S11) may be coupled to the lower end of the oil passage (126). Accordingly, the oil filled in the oil storage space (S11) may be supplied to the compression chamber and / or each bearing surface while being sucked along the rotation shaft (125) through the oil pickup (127) and the oil passage (126) when the rotation shaft (125) rotates.

[0072] The compression unit (C) according to the present embodiment includes a main frame (130), a rotating scroll (140), and a fixed scroll (150). The main frame (130) is fixedly connected to the lower side of the driving motor (120), and the rotating scroll (140) is axially supported by a fixed scroll (150) connected to the lower side of the main frame (130) and can be provided to be rotatable between the main frame (130) and the fixed scroll (150).

[0073] Referring to FIG. 1, the main frame (130) includes a frame plate portion (131), a frame side wall portion (132), and a main support portion (133).

[0074] The frame plate portion (131) is formed in a circular shape, and a main shaft hole (1331) forming a main support portion (133) to be described later can be formed by penetrating through the center in the axial direction.

[0075] The frame side wall portion (132) extends in a cylindrical shape from the lower edge of the frame plate portion (131) and can be fixed by hot pressing or welding to the inner surface of the cylindrical shell (111).

[0076] The main support member (133) may be formed by having a main shaft hole (1331) extending axially therethrough so that the rotary shaft (125) may be rotatably inserted therein. A main bearing (not shown) that supports the main bearing surface portion (1252) of the rotary shaft (125) may be provided in the main shaft hole (1331). Accordingly, the main bearing surface portion (1252) of the rotary shaft (125) may be supported radially while smoothly rotating within the main shaft hole (1331).

[0077] Referring to Fig. 1, the turning scroll (140) includes a turning plate portion (141), a turning wrap (142), and a rotating shaft coupling portion (143).

[0078] The pivot plate (141) is formed in a circular shape and can be accommodated between the frame pivot plate (131) and the fixed pivot plate (151) described later. The upper surface of the pivot plate (141) can be axially supported on the main frame (130) with a back pressure sealing member (not shown) therebetween. Accordingly, the back surface of the pivot plate (141) forms a back pressure chamber (not shown) between it and the main frame (130) facing it.

[0079] The pivoting wrap (142) extends from the lower surface of the pivoting plate portion (141) toward the fixed plate portion (151) to be described later, and is interlocked with the fixed wrap (154) to be described later to form the first compression chamber (V1) and the second compression chamber (V2) described above.

[0080] The orbital wrap (142) may be formed in an involute shape. However, the orbital wrap (142) and the fixed wrap (154) may be formed in various shapes other than the involute shape. For example, the orbital wrap (142) may have a shape that connects multiple circular arcs with different diameters and origins, and the outermost curve may be formed in a roughly elliptical shape with a major axis and a minor axis. The fixed wrap (154) may also be formed in the same manner. Hereinafter, this may be described by defining it as a hybrid or irregular wrap shape.

[0081] The rotary shaft coupling portion (143) can be formed by penetrating axially from the center of the turning plate portion (141). Accordingly, the discharge port (1511) described later can be formed at the center of the turning scroll (140), that is, at an eccentric position from the rotary shaft coupling portion (143).

[0082] A rotary shaft (125) can be rotatably inserted and coupled to the rotary shaft coupling portion (143). Accordingly, the outer circumference of the rotary shaft coupling portion (143) is connected to the rotating wrap (142) to form a first compression chamber (V1) together with the fixed wrap (154) during the compression process.

[0083] The rotation shaft coupling portion (143) can be formed at a height that overlaps the rotation wrap (142) on the same plane. In other words, the rotation shaft coupling portion (143) can be formed at a height that overlaps the eccentric portion (1253) of the rotation shaft (125) on the same plane as the rotation wrap (142).

[0084] Referring to FIG. 1, the fixed scroll (150) according to the present embodiment includes a fixed plate portion (151), a fixed side wall portion (152), a sub-support portion (153), and a fixed wrap (154).

[0085] The fixed plate part (151) may be formed in a circular shape and may be arranged at a preset interval on the lower side of the frame plate part (131). A sub-axial hole (1531) forming a sub-support part (153) to be described later may be formed through the center of the fixed plate part (151) in the vertical direction. A discharge port (1511) may be formed around the sub-axial hole (1531) to communicate with the first compression chamber (V1) and the second compression chamber (V2) to be described later, respectively, through which the compressed refrigerant is discharged to the muffler space (160a) of the discharge cover (160).

[0086] The discharge port (1511) can be formed at an eccentric position from the center of the fixed plate portion (151). In other words, as the sub-axis hole (1531) is formed at the center of the fixed plate portion (151), the discharge port (1511) can be formed at an eccentric position from the sub-axis hole (1531).

[0087] The fixed side wall portion (152) may extend in the vertical direction from the upper edge of the fixed plate portion (151) and be coupled to the frame side wall portion (132) of the main frame (130). An intake port (not shown) that penetrates the fixed side wall portion (152) in the radial direction may be formed in the fixed side wall portion (152). As described above, an end of a refrigerant suction pipe (115) that penetrates the cylindrical shell (111) may be inserted and coupled to the intake port (not shown).

[0088] A cylindrical sub-axis hole (1531) may be formed axially through the center of the sub-support member (153). The sub-axis hole (1531) may be formed on the same axis as the main axis hole (1331) provided in the main frame (130). Accordingly, the inner diameter of the sub-axis hole (1531) may be formed smaller than the inner diameter of the main axis hole (1331).

[0089] The fixed wrap (154) can be formed to extend axially from the upper surface of the fixed plate portion (151) toward the orbiting scroll (140). Since the fixed wrap (154) is formed to correspond to the shape of the orbiting wrap (142) described above, the description of the fixed wrap (154) is replaced with the description of the orbiting wrap (142).

[0090] Referring to Fig. 1, a discharge cover (160) can be coupled to the back surface of a fixed scroll (150). A muffler space (160a) is provided inside the discharge cover (160), and a discharge port (1511) penetrating through the fixed scroll (150) can be accommodated in the muffler space (160a). Accordingly, refrigerant discharged from the compression chamber (V) through the discharge port (1511) moves to the upper space (S2) via the muffler space (160a).

[0091] In the drawing, the unexplained symbol 155 is a sealing protrusion, 170 is an old ring, and 192 is a key fixing ring.

[0092] The scroll compressor according to the above embodiment operates as follows.

[0093] That is, when power is applied to the drive motor (120), rotational force is generated in the rotor (122) and the rotation shaft (125), causing them to rotate, and the rotary scroll (140) eccentrically coupled to the rotation shaft (125) performs a rotational movement with respect to the fixed scroll (150) by the Oldham ring (170).

[0094] Then, the volume of the first compression chamber (V1) and the second compression chamber (V2) gradually decreases from the outside toward the center of each compression chamber (V1) (V2). Then, the refrigerant is sucked into the first compression chamber (V1) and the second compression chamber (V2) through the refrigerant suction pipe (115).

[0095] Then, the refrigerant is compressed while moving along the movement path of each compression chamber (V1)(V2), and the compressed refrigerant is discharged into the muffler space (160a) of the discharge cover (160) through the discharge port (1511) connected to the compression chamber (V1)(V2).

[0096] Then, the refrigerant is discharged through the discharge hole (not shown) provided in the fixed scroll (150) and the main frame (130) into the discharge space (not shown) between the main frame (130) and the drive motor (120), passes through the drive motor (120), and moves to the upper space (S2) of the casing (110) formed on the upper side of the drive motor (120). The refrigerant is separated into refrigerant and oil in the upper space (S2), and the refrigerant is discharged to the outside of the casing (110) through the refrigerant discharge pipe (116), while the oil separated from the refrigerant is recovered to the lower space (S1) of the casing (110) through the oil recovery passage (not shown) described above. This oil is supplied to the compression chamber (V) and / or each bearing surface through the oil passage (126) of the rotating shaft (125) and then returned to the lower space (S1) of the casing (110) forming the oil storage space, repeating a series of processes.

[0097] Meanwhile, as described above, the rotation shaft (125) may be supported radially by having the main bearing surface (1252) forming part of the lower half inserted into the main shaft hole (1331) of the main frame (130), and the sub-bearing surface (1254) inserted into the sub-bearing hole (1531) of the fixed scroll (150). Since the sub-bearing surface (1254) is formed on the same axis as the main bearing surface (1252) with the eccentric portion (1253) interposed therebetween, the outer diameter of the sub-bearing surface (1254) may be formed smaller than that of the main bearing surface (1252). This may increase the surface pressure between the sub-bearing surface (1254) and the sub-bearing facing it, which may lower reliability.

[0098] Taking this into consideration, as described above, a bushing bearing (180) having a preset thickness is combined on the outer surface of the sub-bearing surface portion (1254) to increase the actual outer diameter of the sub-bearing surface portion (1254), thereby reducing the surface pressure between the sub-bearing surface portion (1254) and the sub-bearing (1532).

[0099] However, in the case where the bush bearing (180) is coupled to the sub-bearing surface (1254) of the rotation shaft (125) as described above, when the rotation shaft (125) tilts, the bush bearing (180) tilts together with the sub-bearing surface (1254), and friction loss may occur between the bush bearing (180) and the sub-bearing (1532) facing it.

[0100] Accordingly, in this embodiment, a tilting avoidance portion (182) to be described later is formed between the outer surface of the sub-bearing surface (1254) and the inner surface of the bush bearing (180) facing it, so that even if the rotation shaft (125) tilts, the bush bearing (180) does not tilt or the tilting angle can be minimized. Through this, friction loss between the bush bearing (180) and the sub-bearing (1532) can be suppressed.

[0101] FIG. 2 is a perspective view showing the rotary shaft and the fixed scroll separated from the scroll compressor according to the present embodiment, FIG. 3 is a perspective view showing the rotary shaft and the bushing bearing separated from FIG. 2, FIG. 4 is a cross-sectional view taken along line “Ⅸ-Ⅸ” of FIG. 3, and FIG. 5 is a cross-sectional view showing the rotary shaft and the fixed scroll assembled from FIG. 2.

[0102] Referring to FIGS. 2 to 5, a sub-bearing (1532) may be press-fitted and fixed to a sub-supporting portion (153) of a fixed scroll (150) according to the present embodiment. The sub-bearing (1532) is formed in a cylindrical shape, but is formed to be much thinner than the bushing bearing (180) described above, so that it may be press-fitted to the sub-supporting portion (153). Accordingly, the sub-bearing (1532) may radially support a sub-bearing surface portion (1254) of a rotational shaft (125) to which a bushing bearing (180) described below is coupled.

[0103] Referring to FIGS. 2 and 3, the bush bearing (180) according to the present embodiment can be inserted into and coupled to the sub-bearing surface portion (1254) of the rotation shaft (125). In other words, the bush bearing (180) is formed in a cylindrical shape, but is formed thicker than the sub-bearing (1532) described above, so as to form a bearing surface together with the sub-bearing (1532). Accordingly, the outer circumferential surface of the bush bearing (180) forms the actual outer circumferential surface of the sub-bearing surface portion (1254) of the rotation shaft (125), so that the actual outer diameter of the sub-bearing surface portion (1254) increases. Through this, the surface pressure between the sub-bearing surface portion (1254) of the rotation shaft (1255) and the sub-bearing (1532) of the fixed scroll (150) facing it can be reduced.

[0104] Specifically, the bushing bearing (180) may be fixed by being pressed into the sub-bearing surface (1254) of the rotation shaft (125), or may be fixed using a separate fixing member. This embodiment illustrates an example in which the bushing bearing (180) is fixed to the sub-bearing surface (1254) using a coupling key (191).

[0105] Referring to FIGS. 2 to 5, a key receiving groove (1254a) may be formed in the sub-bearing surface portion (1254) of the rotary shaft (125) so that a coupling key (191) may be inserted therein. The key receiving groove (1254a) may be recessed in the outer circumferential surface of the sub-bearing surface portion (1254) in the radial direction to a preset depth, and may also be formed to be long in the axial direction to a preset length. In other words, the inner end of the coupling key (191) that protrudes in the radial direction of the rotary shaft (125) and extends in the axial direction may be inserted and coupled into the key receiving groove (1254a). Accordingly, the contact area between the rotary shaft (125) and the coupling key (191) may be extended in the axial direction, so that the rotational force of the rotary shaft (125) may be uniformly transmitted to the bushing bearing (180).

[0106] Referring to FIGS. 4 and 5, the inner diameter of the bush bearing (180) can be formed to be almost the same as the outer diameter of the sub-bearing surface portion (1254) of the rotation shaft (125). Accordingly, the bush bearing (180) can be closely inserted into the sub-bearing surface portion (1254) of the rotation shaft (125), thereby suppressing oil flowing between the sub-bearing surface portion (1254) and the bush bearing (180) from moving toward the compression chamber (V).

[0107] A key support groove (180a) may be formed on the inner surface of the bush bearing (180) so that the outer end of the previously described coupling key (191) is inserted therein. The key support groove (180a) may be sunken in the radial direction to a preset depth, but may also be formed to be long in the axial direction. In other words, the key support groove (180a) may be formed to correspond to the key receiving groove (1254a) of the rotary shaft (125). Accordingly, the contact area between the bush bearing (180) and the coupling key is extended in the axial direction, so that the rotational force of the rotary shaft (125) can be uniformly transmitted to the bush bearing (180).

[0108] The inner circumference of the bush bearing (180) may be formed identically along the axial direction, but in some cases, the inner circumference of the bush bearing (180) may be formed to have a plurality of inner diameters along the axial direction. For example, the inner diameter of at least one end among the two ends of the bush bearing (180) may be formed smaller than the inner diameter of the central portion. This embodiment illustrates an example in which the inner diameter of the end of the bush bearing (180) adjacent to the drive motor (120) is formed smaller than the inner diameter of the central portion. In other words, a tilting avoidance portion (182), which will be described later, may be formed at the end of the inner circumference of the bush bearing (180) toward the drive motor (120). Accordingly, when the rotation shaft (125) tilts, the bush bearing (180) can be prevented from tilting together with the rotation shaft (125).

[0109] Referring to FIGS. 2 to 4, the inner circumferential surface of the bush bearing (180) according to the present embodiment may include a support surface portion (181) and a tilting avoidance portion (182). The support surface portion (181) is formed at the center of the inner circumferential surface of the bush bearing (180) and is a portion that is almost in close contact with the sub-bearing surface portion (1254) of the rotation shaft (125), and the tilting avoidance portion (182) is formed at a corner of the inner circumferential surface of the bush bearing (180) and is a portion that is spaced apart from the sub-bearing surface portion (1254) of the rotation shaft (125).

[0110] The support surface (181) can be formed to have an approximately circular shape when projected in the axial direction. For example, when the sub-bearing surface (1254) is formed with the same outer diameter along the axial direction, the support surface (181) can also be formed with the same inner diameter along the axial direction. In other words, the support surface (181) can be formed to correspond to the outer circumferential surface of the sub-bearing surface (1254). Accordingly, the contact area of ​​the support surface (181) with the sub-bearing surface (1254) is expanded, so that the rotational force of the rotational shaft (125) can be effectively transmitted to the bushing bearing (180).

[0111] The tilting avoidance portion (182) may be formed so that the inner diameter of the first stage (182a) adjacent to the driving motor (120) is larger than the inner diameter of the second stage (182b) farther from the driving motor (120). For example, the tilting avoidance portion (182) may be formed so that the inner diameter gradually increases toward the end at the center of the bush bearing (180). Accordingly, even if the rotation shaft (125) tilts, the inner surface of the corner side of the bush bearing (180) does not come into contact with the rotation shaft (125), so that the tilting of the rotation shaft (125) can be suppressed from being transmitted to the bush bearing (180).

[0112] The tilting avoidance portion (182) may be formed on a portion of the inner surface of the bush bearing (180). For example, the axial length (L2) of the tilting avoidance portion (182) may be formed to be less than or equal to half of the axial length (L1) of the bush bearing (180), specifically, less than or equal to 1 / 3. In other words, when the tilting avoidance portion (182) is formed on one axial end of the bush bearing (180), the axial length (L2) of the tilting avoidance portion (182) may be formed to be less than or equal to 1 / 6 of the axial length (L1) of the bush bearing (180). Accordingly, a sufficient radial support area of ​​the bush bearing (180) can be secured during normal operation.

[0113] The tilting avoidance portion (182) may be formed with a single angle of inclination, may be formed with multiple angles of inclination, and may be formed by combining multiple shapes, depending on the case. This embodiment illustrates an example in which the tilting avoidance portion (182) is formed by combining multiple shapes.

[0114] Specifically, the tilting avoidance portion (182) may include a first avoidance portion (1821), a second avoidance portion (1822), and a third avoidance portion (1823). The first avoidance portion (1821) is a portion adjacent to the driving motor (120), the second avoidance portion (1822) is a portion distant from the driving motor (120), and the third avoidance portion (1823) is a portion connecting the first avoidance portion (1821) and the second avoidance portion (1822).

[0115] The first skin portion (1821) can be formed with the same inner diameter along the axial direction. In other words, the inner diameter of the first skin portion (1821) on the side adjacent to the driving motor (120) and the inner diameter of the side far from the driving motor (120) can be formed to be the same. Accordingly, while facilitating processing of the first skin portion (1821), the end thickness of the bushing bearing (180) can be appropriately secured, thereby suppressing damage to the bushing bearing (180) due to collision with the rotating shaft (125).

[0116] The second skin portion (1822) may be formed to be inclined along the axial direction. In other words, the inner diameter of the second skin portion (1822) on the side adjacent to the driving motor (120) may be formed to be larger than the inner diameter on the side farther from the driving motor (120). Accordingly, the inner diameter of the second skin portion (1822) may gradually increase toward the driving motor (120) and may be formed into an inclined cross-sectional shape. Through this, in the second skin portion (1822), the gap between the outer surface of the rotating shaft (125) and the inner surface of the bushing bearing (180) may gradually increase toward the driving motor (120).

[0117] The axial length (L22) of the second skin portion (1822) may be formed to be greater than or equal to the axial length (L21) of the first skin portion (1821). For example, the axial length (L22) of the second skin portion (1822) may be formed to be greater than the axial length (L21) of the first skin portion (1821). Accordingly, the actual inclination angle of the tilting avoidance portion (1822) may be formed as large as possible to enhance the tilting avoidance effect.

[0118] The third skin (1823) can be formed flat. In other words, the third skin (1823) can be formed parallel to one end surface of the bushing bearing (180), for example, the end surface of the first skin (1821). Accordingly, the third skin (1823) can be easily processed.

[0119] Although not shown in the drawing, the third skin (1823) may be formed to be inclined at a preset angle with respect to one end surface of the bushing bearing (180), for example, the end surface of the first skin (1821). In other words, the third skin (1823) may be formed to be inclined at a smaller angle than the angle of inclination of the second skin (1822) with respect to the end surface of the bushing bearing (180). In this case, the length of the second skin (1822) may be reduced by the amount by which the third skin (1823) is inclined, thereby increasing the strength of the second skin (1822).

[0120] In addition, the third skin portion (1823) may be formed to be narrower than or equal to the first skin portion (1821) and / or the second skin portion (1822). For example, the radial width (D3) of the third skin portion (1823) may be formed to be smaller than the radial width (D1) of the first skin portion (1821) and / or the radial width (D2) of the second skin portion (1822). Accordingly, the radial width (D1) of the second skin portion (1822) can sufficiently secure the thickness of the first skin portion (1821) under the same conditions, thereby suppressing damage to the first skin portion (1821).

[0121] As described above, when a bushing bearing (180) is coupled between the sub-bearing surface (1254) of the rotation shaft (125) and the sub-support portion (153) of the fixed scroll (150) that supports it in the radial direction, that is, to the sub-bearing surface portion (1254), the actual outer diameter of the sub-bearing surface portion (1254) increases by the thickness of the bushing bearing (180), so that the surface pressure applied to the sub-support portion (153) of the fixed scroll (150) can be reduced. Through this, the reliability of the sub-bearing (1532) inserted into the sub-support portion (153) can be improved.

[0122] At this time, if a tilting avoidance portion (182) is provided on the inner peripheral edge of the bush bearing (180), it is possible to avoid contact between the outer peripheral edge of the rotary shaft (125) and the inner peripheral edge of the bush bearing (180) when the rotary shaft (125) is tilted. In other words, since the tilting avoidance portion (182) is formed on the inner peripheral edge of the bush bearing (180), even if the rotary shaft (125) tilts during operation of the compressor, the rotary shaft (125) can be prevented from contacting the inner peripheral edge of the bush bearing (180) by the bush bearing. Accordingly, the tilting force of the rotary shaft (125) is blocked from being transmitted to the bush bearing (180), thereby preventing the bush bearing (180) from being tilted together with the rotary shaft (125). Through this, even if a bushing bearing (180) is additionally coupled to the sub-bearing surface (1254) of the rotation shaft (125), it is possible to suppress an increase in the surface pressure at the sub-bearing (1532) of the fixed scroll (150) due to tilting of the bushing bearing.

[0123] Fig. 6 is a schematic diagram illustrating the operational effect of a bushing bearing equipped with a tilting avoidance part according to the present embodiment.

[0124] Referring to FIG. 6, when a tilting avoidance portion (182) is formed at the inner peripheral edge of the bush bearing (180) as in the present embodiment, the point of action (hereinafter, abbreviated as the point of action) (P2) of the bearing reaction force can be formed within the generation range (A) of the support point (hereinafter, abbreviated as the support point) (P1) of the axial support force acting on the inner peripheral surface of the bush bearing (180). Accordingly, even if the rotation shaft (125) tilts, the bush bearing (180) can be prevented from tilting, or even if it tilts, it can be suppressed to a minimum.

[0125] For example, if the entire inner surface of the bush bearing (180) is formed with the same inner diameter, when the rotation shaft (125) tilts, the support point (P1) is formed at the corner of the inner surface of the bush bearing (180), while the point of action (P2) is formed in the middle of the outer surface of the bush bearing (180). Then, the tilting amount of the rotation shaft (125) is transmitted to the corner of the inner surface of the bush bearing (180), so that the bush bearing (180) tilts together with the rotation shaft (125). Then, the bush bearing (180) applies a strong surface pressure to the sub-bearing (1532) of the fixed scroll (150), which may increase frictional loss between the outer surface of the bush bearing (180) and the inner surface of the sub-bearing (1532).

[0126] However, as previously explained, when the tilting avoidance portion (182) is formed at the inner peripheral edge of the bush bearing (180), the support point (P1) is formed in the middle of the inner peripheral edge of the bush bearing (180), that is, within the support surface portion (181) of the bush bearing (180). In other words, the occurrence range (A) of the support point (P1) is reduced by the tilting avoidance portion (182). Accordingly, the point of action (P2) of the bearing reaction force acting on the outer peripheral edge of the bush bearing (180) is formed axially close to the support point (P1), thereby suppressing or minimizing the tilting of the bush bearing (180).

[0127] In other words, when a tilting avoidance portion (182) is formed on the inner circumferential edge of the bushing bearing (180), even if the rotational axis (125) tilts by an arbitrary tilting angle (α), the tilting avoidance portion (182) absorbs and offsets the tilting amount of the rotational axis (125). Then, when the rotational axis (125) tilts, the occurrence range (A) of the support point (P1) for the sub-bearing surface (1254) of the rotational axis (125) is limited to the center of the bushing bearing (180). Then, even if the rotation axis (125) is tilted by an arbitrary tilting angle (α), the support point (P1) generated on the inner surface of the bush bearing (180) by the sub-bearing surface (1254) of the rotation axis (125) is positioned close to the point of action (P2) acting on the outer surface of the bush bearing (180) by the sub-bearing (1532). Accordingly, by combining the bush bearing (180) to the sub-bearing surface (1254) of the rotation axis (125), the actual outer diameter of the sub-bearing surface (1254) can be increased, while the gap (G) between the support point (P1) and the point of action (P2) can be reduced. Through this, the bearing area between the bush bearing (180) and the sub-bearing (1532) of the fixed scroll (150) can be expanded to reduce the surface pressure, while preventing the bush bearing (180) from tilting when the rotation shaft (125) tilts. This can prevent friction loss and / or damage between the bush bearing (180) and the sub-bearing (1252) compared to the conventional case where the inner surface of the bush bearing (180) is formed with the same inner diameter, thereby increasing reliability.

[0128] In this case, the tilting avoidance portion (182) may be formed in a portion where the hydraulic pressure does not act as much as possible or where the hydraulic pressure acts the least. Normally, the hydraulic pressure applied to the bush bearing (180) is greatest at the center of the bush bearing (180) and decreases toward both ends, but may decrease rapidly from a point approximately 1 / 6 from both ends. Accordingly, it may be preferable that the axial length (L2) of the tilting avoidance portion (182) be formed to be less than or equal to half of the axial length (L1) of the bush bearing (180), specifically less than or equal to 1 / 3. In other words, when the tilting avoidance portion (182) is formed on one axial end of the bush bearing (180), it may be desirable for the axial length (L2) of the tilting avoidance portion (182) to be formed to be less than or equal to 1 / 6 of the axial length (L1) of the bush bearing (180). Through this, a sufficient radial support area of ​​the bush bearing (180) can be secured during normal operation.

[0129] Meanwhile, there are other examples of bushing bearings as follows.

[0130] That is, in the embodiment described above, the tilting avoidance portion is formed in steps, but in some cases, a fueling hole may be formed in the tilting avoidance portion.

[0131] Fig. 7 is a perspective view showing another embodiment of a bushing bearing, and Fig. 8 is a cross-sectional view showing the bushing bearing of Fig. 7 coupled to a rotating shaft.

[0132] Referring to FIGS. 7 and 8, the basic configuration and the resulting operational effects of the bush bearing (180) according to the present embodiment are almost identical to those of the aforementioned embodiment. For example, the inner circumference of the bush bearing (180) according to the present embodiment includes a support surface portion (181) and a tilting avoidance portion (182), wherein the support surface portion (181) may be formed at the center of the inner circumference of the bush bearing (180), and the tilting avoidance portion (182) may be formed at the end of the inner circumference of the bush bearing (180).

[0133] The support surface (181) may be formed to have the same inner diameter along the axial direction, and the tilting avoidance portion (182) may be formed to be inclined toward the outer circumferential surface as it goes toward the driving motor (120). Accordingly, when the rotation shaft (125) tilts, the tilting force is suppressed from being transmitted to the bush bearing (180), thereby more effectively preventing the bush bearing (180) from tilting.

[0134] However, in the present embodiment, the tilting avoidance part (182) may be formed as a single avoidance part, that is, as a single inclined surface from the first end (182a) to the second end (182b) of the tilting avoidance part (182). In this case, the configuration and the resulting operational effect of the tilting avoidance part (182) are almost the same as those of the aforementioned embodiment, so a detailed description thereof will be replaced with the description of the aforementioned embodiment. However, in the case where the tilting avoidance part (182) is formed as a single inclined angle, not only can the tilting avoidance part (182) be easily processed to reduce the manufacturing cost, but also, compared to the aforementioned embodiment, the bushing bearing (180) at the end side can be thickened, so that reliability can be improved.

[0135] Meanwhile, another example of a bushing bearing is as follows.

[0136] That is, in the above-described embodiment, the bushing bearing is formed in a blocked cylindrical shape, but in some cases, a lubrication hole may be formed in the bushing bearing.

[0137] Fig. 9 is a perspective view showing another embodiment of a rotary shaft and a bushing bearing, and Fig. 10 is a cross-sectional view showing the bushing bearing coupled to the rotary shaft in Fig. 9.

[0138] Referring to FIGS. 9 and 10, the bushing bearing (180) may include an oil supply hole (183). The oil supply hole (183) is a portion of a passage through which a portion of the oil sucked in through the oil passage (126) of the rotating shaft (125) is supplied toward the eccentric portion (1253) of the rotating shaft (125) and the sealing protrusion (155) of the fixed scroll (150).

[0139] For example, an oil hole (1261) may be formed on the sub-bearing surface (1254) of the rotating shaft (125) so as to penetrate from the inner surface of the oil passage (126) to the outer surface of the sub-bearing surface (1254), and an oil supply hole (183) may be formed on the bush bearing (180) so as to penetrate from the inner surface to the outer surface of the bush bearing (180) so as to communicate with the oil hole (1261). In other words, the oil supply hole (183) may be formed on the support surface (181) of the bush bearing (180), but may be formed so as to communicate with the oil hole (1261) provided on the sub-bearing surface (1254) of the rotating shaft (125). Accordingly, oil passing through the oil passage (126) and the oil hole (1261) can be smoothly supplied to the bearing surface between the outer surface of the bushing bearing (180) and the sub-support part (153) facing it through the oil supply hole (183).

[0140] In this case, the oil supply hole (183) is connected to the oil hole (1261) of the rotation shaft (125), and may be formed on the same line in the radial direction as the oil hole (1261) or may be formed at a position where at least a portion overlaps. The present embodiment shows an example in which the oil supply hole (183) is formed to be located on the same line in the radial direction as the oil hole (1261) of the rotation shaft (125). Accordingly, the gap between the oil supply hole (183) and the oil hole (1261) is minimized, so that the oil passing through the oil hole (1261) can move more quickly to the oil supply hole (183). Through this, the outer surface of the bush bearing (180) and the sub-support part (153) facing it can slide smoothly without seizure.

[0141] Referring to Fig. 10, an annular sealing surface portion (184) may be formed on the inner surface of the bush bearing (180). In other words, the sealing surface portion (184) may be formed on the inner surface of the bush bearing (180), but the gap between the sealing surface portion (184) and the sub-bearing surface portion (1254) may be formed narrower than the gap between the tilting avoidance portion (182). Accordingly, it is possible to prevent high-pressure refrigerant contained in the internal space of the oil pickup (127) and / or the casing (110) from flowing into the gap between the inner surface of the bush bearing (180) and the outer surface of the sub-bearing surface portion (1254).

[0142] In this case, the sealing surface (184) may be formed to surround the periphery of the oil supply hole (183). In other words, the sealing surface (184) may extend from the oil supply hole (183) by the same width in all directions. For example, the sealing surface (185) may extend from the oil supply hole (183) by at least 1 mm in all directions. Accordingly, the sealing surface (184) secures a sufficient area around the oil supply hole (183), so that not only can the refrigerant described above be prevented from flowing into the oil supply passage, but also the oil supplied to the oil supply hole (183) of the bush bearing (180) through the oil passage (126) and the oil hole (1261) of the rotating shaft (125) can be smoothly supplied to the oil supply hole (183) without leaking between the sub-bearing surface (1254) and the bush bearing (180).

[0143] An oil supply groove (185) may be formed on the outer surface of the bush bearing (180). The oil supply groove (185) may extend in the axial direction. In other words, one end of the oil supply groove (185) may be connected to the oil supply hole (183), and the other end of the oil supply groove (185) may extend to one end of the bush bearing (180). Accordingly, oil moving to the outer surface of the bush bearing (180) through the oil supply hole (183) moves along the oil supply groove (185) in the axial direction of the bush bearing (180), thereby evenly lubricating the space between the outer surface of the bush bearing (180) and the inner surface of the sub-bearing (1532) facing it.

[0144] In this case, a communication groove (186) may be formed sunken in one end of the oil supply groove (185), that is, in the end of the first side (1821) of the tilting avoidance portion (182), to connect the inner surface of the bushing bearing (180) and the oil supply groove (185). Accordingly, the oil supply groove (185) may be communicated with the tilting avoidance portion (182) through the communication groove (186).

[0145] In the case where a communication groove (186) is formed at one end of the oil supply groove (185) as described above, a portion of the oil moving axially through the oil supply groove (185) flows into the tilting avoidance portion (182) through the communication groove (186) and accumulates in the tilting avoidance portion (182). Then, while the tilting avoidance portion (182) is filled with high-pressure oil, the space between the sub-bearing surface portion (1254) and the bushing bearing (180) can be tightly sealed. Accordingly, the high-pressure refrigerant described above can be more effectively prevented from flowing into the gap between the inner surface of the bushing bearing (180) and the outer surface of the sub-bearing surface portion (1254).

[0146] Meanwhile, in the above-described embodiments, the tilting avoidance portion (182) was described mainly with reference to an example in which the tilting avoidance portion (182) was formed at the end adjacent to the driving motor (120). However, in some cases, the tilting avoidance portion (182) may be formed at each end of the inner surface of the bush bearing (180) or may be formed only at the end farther from the driving motor (120). In these cases as well, when the rotation shaft (125) is tilted, the tilting force is suppressed from being transmitted to the bush bearing (180), thereby more effectively preventing the bush bearing (180) from tilting.

[0147] Meanwhile, in the above-described embodiments, the tilting avoidance portion (182) was described mainly with reference to an example in which the tilting avoidance portion (182) was formed on the inner surface of the bush bearing (180). However, in some cases, the tilting avoidance portion (182) may be formed on the inner surface of the bush bearing (180) and / or the sub-bearing surface portion (1254) of the rotation shaft (125). In other words, a tilting avoidance portion (not shown) having a preset depth may be formed on the sub-bearing surface portion (1254) of the rotation shaft (125) facing the edge of the inner surface of the bush bearing (180). In this case, the tilting avoidance portion may be formed in the shape of an annular groove having the same depth, or may be formed in the opposite direction to the above-described embodiments, that is, to become deeper as it goes from the center of the sub-bearing surface portion (1254) toward the eccentric portion (1253). In these cases, the tilting force of the rotation axis (125) can be prevented from being transmitted to the bush bearing (180) when tilting, thereby preventing the bush bearing (180) from being tilted.

[0148] The present invention can be used in a through-pipe scroll compressor.

Claims

1. Casing; A driving motor provided inside the above casing; A fixed scroll fixed to the casing on one side of the above driving motor; A rotating scroll that forms a compression chamber between itself and the fixed scroll while performing a rotating motion with respect to the fixed scroll; A rotary shaft which is coupled to the rotor of the driving motor at one end and rotatably coupled to the fixed scroll at the other end by eccentrically penetrating the rotating scroll; and Includes a bushing bearing coupled to the above rotational axis and provided between the fixed scroll and the rotational axis, The above bushing bearing, A scroll compressor in which a tilting avoidance part is formed on the inner surface facing the outer surface of the above-mentioned rotation shaft to avoid contact with the above-mentioned rotation shaft.

2. In paragraph 1, The above tilting avoidance part is, A scroll compressor in which the inner diameter of the first stage adjacent to the driving motor is formed larger than the inner diameter of the second stage farther from the driving motor.

3. In paragraph 2, The above tilting avoidance part is, A scroll compressor in which at least a portion between the first stage and the second stage is formed as a tapered inclined surface.

4. In paragraph 2, The above tilting avoidance part is, A scroll compressor formed with at least one step surface between the first stage and the second stage.

5. In paragraph 1, The above tilting avoidance part is, A first skin portion adjacent to the above driving motor; and It includes a second skin portion located further from the driving motor than the first skin portion, The above second skin part is, A scroll compressor formed to be inclined at a preset angle with respect to the cross-section of the first skin section.

6. In paragraph 5, The axial length of the above tilting avoidance part is formed to be less than or equal to half the axial length of the above bushing bearing, The axial length of the above second skin is A scroll compressor formed to have an axial length greater than or equal to the first skin portion.

7. In paragraph 6, The above first skin part is, A scroll compressor in which the inner diameter is formed identically along the axial direction of the rotating shaft.

8. In paragraph 5, A third skin portion is further included between the first skin portion and the second skin portion, The radial width of the third skin section is A scroll compressor formed to have a radial width smaller than or equal to the radial width of the second skin.

9. In paragraph 8, The above third skin is, A scroll compressor formed parallel to the cross-section of the first skin portion or formed at an inclination angle smaller than the inclination angle of the second skin portion.

10. In any one of paragraphs 1 to 9, An oil passage is formed inside the above-mentioned rotating shaft, and an oil hole is formed that penetrates from the inner surface of the oil passage to the outer surface of the above-mentioned rotating shaft. The above bushing bearing, A scroll compressor in which a fueling hole is formed penetrating from the inner surface to the outer surface.

11. In paragraph 10, The above fueling hole is, A scroll compressor formed so that at least a portion thereof radially overlaps the oil hole.

12. In paragraph 10, The above fueling hole is, A scroll compressor spaced apart from the above tilting avoidance section in the axial direction by a preset distance.

13. In paragraph 12, A sealing surface is formed around the above-mentioned fueling hole, The width of the above sealing surface is A scroll compressor formed with a radius greater than or equal to the radius of the above-mentioned fueling hole.

14. In paragraph 10, An oil supply groove extending along the axial direction is formed on the outer surface of the above bushing bearing, The above refueling home is, A scroll compressor formed to be connected to the above-mentioned fuel supply hole.

15. In paragraph 14, A scroll compressor in which a communication groove is formed sunken into one end of the above-mentioned oil supply groove to connect the inner surface of the bushing bearing and the above-mentioned oil supply groove.

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