Scroll compressor

Abstract

Disclosed herein is a scroll compressor. The scroll compressor includes a casing, a main frame, a fixed scroll, an orbiting scroll, and a back pressure plate, wherein the back pressure plate is inserted into the main frame and may include at least one oil supply passage penetrating from a back pressure surface facing away from the orbiting scroll to a thrust surface facing the orbiting scroll. Accordingly, a back pressure chamber assembly is simplified, thus reducing manufacturing costs, the sealing of the back pressure chamber is increased, thus reducing suction loss due to overheating of a suctioned refrigerant, and friction loss between the back pressure chamber assembly and the orbiting scroll can be reduced to increase energy efficiency, even while increasing the area of the back pressure chamber.

Description

Scroll compressor

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

[0002] Compressors used in refrigeration cycles, such as those in refrigerators or air conditioners, perform the function of compressing refrigerant gas and transferring it to the condenser. Rotary compressors or scroll compressors are primarily used in air conditioners; scroll compressors are being applied not only to air conditioners but, more recently, also to compressors for water heaters that require higher compression ratios than air conditioners.

[0003] Scroll compressors are classified as hermetic compressors if the drive unit (or electric unit) and the compressor unit are contained in a single casing, and as open compressors if they are provided independently; they are classified as upper compression type if the compressor unit is located above the drive unit, and lower compression type if it is located below; and they can be classified as low pressure type if the space housing the drive unit is for suction pressure, and high pressure type if it is for discharge pressure.

[0004] Additionally, the scroll compressor may include a fixed scroll equipped with a fixed wrap and a rotary scroll equipped with a rotary wrap that engages with the fixed wrap. Scroll compressors can be classified into fixed back pressure and rotary back pressure types depending on the back pressure method. The fixed back pressure method is a method in which a back pressure chamber is formed on the back surface of the fixed scroll, and the rotary back pressure method is a method in which a back pressure chamber is formed on the back surface of the rotary scroll. Typically, in the fixed back pressure method, the fixed scroll is constrained in the circumferential direction but is configured to be movable in the axial direction, so it is sometimes described as a non-rotating scroll. Hereinafter, it will be described uniformly as a fixed scroll.

[0005] Patent Document 1 (US2015 / 0345493 A1) discloses a low-pressure and fixed-back pressure type scroll compressor. A fixed-back pressure type scroll compressor like Patent Document 1 requires the addition of multiple parts to form a back pressure chamber on the back surface of the fixed scroll, which can increase manufacturing costs.

[0006] Patent Document 2 (JP6274281 B1) discloses a low-pressure type scroll compressor with a slewing back pressure method. In a scroll compressor with a slewing back pressure method like Patent Document 2, a back pressure chamber assembly is inserted into a main frame facing the slewing scroll, thereby expanding the back pressure chamber area compared to the conventional slewing back pressure method and enabling stable support of the slewing scroll. However, in Patent Document 2, the back pressure chamber assembly slides in contact with the slewing scroll, increasing the friction area and potentially lowering energy efficiency due to friction loss. This decrease in energy efficiency can occur even more significantly in the case of large-capacity scroll compressors.

[0007] The objective of the present invention is to provide a scroll compressor capable of reducing manufacturing costs by simplifying the back pressure chamber assembly that brings the rotating scroll and the stationary scroll into close contact.

[0008] Another objective of the present invention is to provide a scroll compressor capable of stably supporting a slewing scroll by expanding the area of ​​the back pressure chamber.

[0009] Another objective of the present invention is to provide a scroll compressor capable of increasing energy efficiency by expanding the area of ​​the back pressure chamber while reducing friction loss between the back pressure chamber assembly and the slewing scroll.

[0010] Another objective of the present invention is to provide a scroll compressor capable of increasing the suction volume while simultaneously increasing the wrap strength.

[0011] To achieve the objective of the present invention, a scroll compressor comprising a casing, a main frame, a fixed scroll, a slewing scroll, and a back pressure plate may be provided. The casing may be separated into a low-pressure section, in which the internal space forms a suction space, and a high-pressure section, in which the internal space forms a discharge space. The main frame may be provided within the internal space of the casing. The fixed scroll may be coupled to one side of the main frame. The slewing scroll may be provided between the main frame and the fixed scroll to form a compression chamber between it and the fixed scroll. The back pressure plate may be provided on one side of the main frame facing the slewing scroll to press the slewing scroll toward the fixed scroll. The back pressure plate may include at least one lubrication passage penetrating from the back pressure surface facing away from the slewing scroll to the thrust surface facing the slewing scroll. Through this, manufacturing costs can be reduced by simplifying the back pressure chamber assembly that brings the rotating scroll and the stationary scroll into close contact, the rotating scroll can be stably supported by expanding the area of ​​the back pressure chamber for pressurizing the rotating scroll toward the stationary scroll, and energy efficiency can be increased by smoothly supplying oil between the back pressure plate and the rotating scroll to reduce friction loss between them.

[0012] For example, a plate receiving groove into which the back pressure plate is inserted may be formed in the main frame. A back pressure groove forming a back pressure chamber may be formed on at least one of the back pressure surface of the back pressure plate and one side of the plate receiving groove facing it. One end of the fluid supply passage may be connected to the back pressure groove.

[0013] For example, a first back pressure passage may be formed by continuously penetrating the fixed scroll and the main frame. The back pressure groove may be connected to the high-pressure portion of the casing through the first back pressure passage.

[0014] Additionally, a first back pressure passage and a second back pressure passage may be formed separately from each other in the fixed scroll and the main frame. The back pressure groove may consist of a first back pressure groove that communicates with the high-pressure part of the casing through the first back pressure passage, and a second back pressure groove that is separated from the first back pressure groove and communicates with the compression chamber through the second back pressure passage.

[0015] For example, the above-mentioned supply passage may include a first supply passage communicating with the first back pressure groove and a second supply passage communicating with the second back pressure groove. The total cross-sectional area of ​​the first supply passage may be formed to be smaller than or equal to the total cross-sectional area of ​​the second supply passage.

[0016] Specifically, the first lubrication passage may consist of a lubrication hole penetrating the back pressure plate and a lubrication groove formed on the thrust surface of the back pressure plate in communication with the lubrication hole. The cross-sectional area of ​​the lubrication groove may be formed to be larger than the cross-sectional area of ​​the lubrication hole.

[0017] In this case, the above-mentioned lubrication holes are formed in multiple numbers at predetermined intervals along the circumferential direction, and the above-mentioned lubrication grooves can be formed so that each of the multiple lubrication holes is individually connected.

[0018] Alternatively, the above-mentioned lubrication holes may be formed in multiple numbers at predetermined intervals along the circumferential direction, and the above-mentioned lubrication groove may be formed to accommodate the multiple lubrication holes collectively.

[0019] In addition, the second flow channel may be formed such that at least a portion thereof is located on a different radial line from the first flow channel.

[0020] In addition, a drainage passage connecting the inner surface and the outer surface of the back pressure plate may be formed in the back pressure plate.

[0021] Specifically, it may be formed as a hole penetrating between the inner and outer surfaces of the back pressure plate, or as a recessed groove on the thrust surface of the back pressure plate facing the pivoting scroll.

[0022] In addition, a lubrication guide groove having a predetermined depth may be formed on the back surface of the rotary scroll facing the thrust surface of the back pressure plate.

[0023] As another example, the above-described slewing scroll may include a slewing plate section, a slewing wrap, and a rotational shaft coupling section. The slewing plate section may be provided between the main frame and the fixed scroll and may be eccentrically coupled to the rotational shaft. The slewing wrap may be provided to extend from one side of the slewing plate section and engage with the fixed wrap of the fixed scroll to form a compression chamber. The rotational shaft coupling section may overlap the slewing wrap and the rotational shaft radially at the center of the slewing plate section and extend in the axial direction of the rotational shaft. A portion of the slewing wrap may extend from the front end surface of the rotational shaft insertion section facing the fixed scroll. Through this, the distance between the bearing reaction force and the gas reaction force acting on the slewing scroll is reduced, thereby decreasing the overturning moment of the slewing scroll. Consequently, the behavior of the slewing scroll is stabilized, thereby suppressing leakage between the compression chambers and simultaneously lowering the back pressure, which can reduce friction loss between the scrolls. At the same time, by forming a compression chamber up to the center of the rotating scroll, the volumetric efficiency can be improved as the compression ratio increases.

[0024] For example, the aforementioned swivel plate portion may be provided with a swivel step surface between the outer surface of the swivel wrap and the inner surface of the swivel wrap facing it, and the aforementioned fixed wrap may be provided with a fixed step surface corresponding to the swivel step surface. At least a portion of the aforementioned back pressure plate may be formed to overlap with a compression chamber located closer to the center than the swivel step surface when projected in the axial direction. Through this, the center of the swivel scroll, which is subjected to a relatively high compressive force, can be stably supported, thereby effectively blocking leakage between the compression chambers.

[0025] The scroll compressor according to the present invention can secure the actual back pressure chamber area as large as possible by providing a back pressure chamber assembly forming a back pressure chamber inside the main frame. Through this, the back pressure area supporting the slewing scroll is expanded, thereby enabling stable support of the slewing scroll.

[0026] In the scroll compressor according to the present invention, a lubrication passage connecting the back pressure surface and the thrust surface is formed in the back pressure plate forming the back pressure chamber assembly, thereby allowing a portion of the oil flowing into the back pressure chamber to be rapidly supplied to the thrust surface. Through this, the area of ​​the back pressure chamber can be expanded while smoothly supplying oil between the back pressure plate and the slewing scroll, thereby reducing friction loss between the back pressure plate and the slewing scroll and increasing energy efficiency.

[0027] In addition, the scroll compressor according to the present invention can form a high discharge-side back pressure while simultaneously lowering the intermediate-side back pressure as the back pressure chamber is connected to the high-pressure part of the casing that forms the discharge pressure as well as to the compression chamber that forms the intermediate pressure. Through this, leakage between the compression chambers on the discharge side can be effectively suppressed, and excessive contact between the scrolls on the suction side can be suppressed, thereby further increasing the compression efficiency of the scroll compressor.

[0028] In addition, the scroll compressor according to the present invention is formed such that the rotating shaft insertion part overlaps radially with the slewing wrap, and at the same time, a portion of the slewing wrap is extended on the leading edge of the rotating shaft insertion part, thereby allowing a compression chamber to be formed in the center of the slewing scroll. Through this, the volumetric efficiency can be improved as the compression ratio increases while the compression cycle of the compression chamber is lengthened as the rotating shaft insertion part extends toward the slewing wrap. At the same time, the wrap height at the discharge ends of the fixed wrap and the slewing wrap is lowered and the wrap thickness is increased, thereby increasing the wrap strength of the fixed wrap and the slewing wrap and suppressing wrap breakage.

[0029] FIG. 1 is a cross-sectional view showing a scroll compressor according to the present embodiment.

[0030] FIG. 2 is a perspective view showing the back pressure chamber assembly in FIG. 1 disassembled.

[0031] FIG. 3 is a plan view showing the back pressure chamber assembly assembled in FIG. 2.

[0032] FIG. 4 is a bottom view showing the back pressure chamber assembly assembled in FIG. 2.

[0033] FIGS. 5 and FIGS. 6 are the "V-V" and "VI-VI" cross-sectional views of FIGS. 4.

[0034] FIG. 7 is a cross-sectional view shown to explain the working effect of the back pressure chamber assembly according to the present embodiment.

[0035] FIG. 8 is a perspective view showing another embodiment of the back pressure plate in the back pressure chamber assembly.

[0036] FIGS. 9 and FIGS. 10 are perspective views showing other embodiments of the back pressure plate in the back pressure chamber assembly.

[0037] Hereinafter, a scroll compressor according to the present invention will be described in detail based on an embodiment illustrated in the attached drawings.

[0038] Scroll compressors can be classified into hermetic or open types depending on whether the drive motor and the compressor unit are installed together within the internal space of the casing. This embodiment describes a hermetic scroll compressor as a representative example. However, it can be applied equally to an open scroll compressor.

[0039] In addition, scroll compressors can be classified into stationary scroll compressors and mobile scroll compressors. Stationary types are typically used for building HVAC, while mobile types are used for vehicle HVAC. This embodiment describes a stationary scroll compressor as a representative example. However, the same applies to mobile scroll compressors.

[0040] In addition, scroll compressors can be classified into low-pressure or high-pressure types depending on the pressure of the refrigerant filled in the internal space of the casing. In the low-pressure type, the internal space of the casing is filled with refrigerant at the suction pressure, while in the high-pressure type, the internal space of the casing is filled with refrigerant at the discharge pressure. This embodiment is described using a low-pressure scroll compressor as a representative example. However, it can be applied equally to high-pressure scroll compressors.

[0041] In addition, scroll compressors can be classified into upper compression and lower compression types depending on the installation location of the compression section. In the upper compression type, the compression section is installed above the drive motor, while in the lower compression type, the compression section is installed below the drive motor. This embodiment is described using an upper compression type scroll compressor as a representative example. However, it can be applied equally to a lower compression type scroll compressor.

[0042] In addition, scroll compressors can be classified into single-rotation scroll compressors and mutual-rotation scroll compressors depending on whether the scroll rotates. A single-rotation scroll compressor is configured such that one scroll is fixed or its rotational movement is restricted while the other scroll performs a pivotal movement, whereas a mutual-rotation scroll compressor is configured such that both scrolls rotate. This embodiment is described using a single-rotation scroll compressor as a representative example. However, it can be applied in the same way to a mutual-rotation scroll compressor.

[0043] In addition, scroll compressors can be classified into vertical scroll compressors, in which the rotation axis is positioned perpendicular to the ground, and horizontal scroll compressors, in which the rotation axis is positioned parallel to the ground. For example, in a vertical scroll compressor, the upper side can be defined as the side opposite to the ground, and the lower side as the side facing the ground. The following description uses a vertical scroll compressor as an example. However, it can be applied in the same or similar way to a horizontal scroll compressor. Therefore, in the following description, the axial direction is understood as the axial direction of the rotation axis and the radial direction as the radial direction of the rotation axis; the axial direction can be understood as the up-down direction, the radial direction as the left-right side, the inner circumference as the upper surface, and the axial and radial directions as the side.

[0044] FIG. 1 is a cross-sectional view showing a scroll compressor according to the present invention.

[0045] Referring to FIG. 1, the scroll compressor according to the present embodiment may have a drive motor (120) forming a drive unit in the lower half of the casing (110), and a main frame (130), a fixed scroll (140), a pivoting scroll (150), and a back pressure chamber assembly (160) forming a compression unit on the upper side of the drive motor (120). The drive unit may be coupled to one end of a rotating shaft (125), and the compression unit may be coupled to the other end of the rotating shaft (125). Accordingly, the compression unit is connected to the drive unit by the rotating shaft (125) and operates by the rotational force of the drive unit.

[0046] The casing (110) may include a cylindrical shell (111), an upper cap (112), and a lower cap (113).

[0047] The cylindrical shell (111) has a cylindrical shape with open upper and lower ends, and the aforementioned drive motor (120) and main frame (130) can be inserted and fixed into the inner surface. A refrigerant suction pipe (117), to be described later, can be penetrated and connected to the upper half of the cylindrical shell (111), for example, the upper side of the drive motor (120).

[0048] The upper cap (112) can be joined to cover the open upper end of the cylindrical shell (111), and the lower cap (113) can be joined to cover the open lower end of the cylindrical shell (111). Accordingly, the internal space of the casing (110) can be sealed.

[0049] An annular high-low pressure separator plate (114) can be inserted and connected between the cylindrical shell (111) and the upper cap (112). In other words, the outer side of the high-low pressure separator plate (114) is connected between the cylindrical shell (111) and the upper cap (112), and the inner side of the high-low pressure separator plate (114) can be connected in close contact with the back surface of the fixed scroll (140). Accordingly, the internal space of the casing (110) can be separated into a low-pressure section (110a) forming a suction space and a high-pressure section (110b) forming a discharge space, centered around the high-low pressure separator plate (114).

[0050] A refrigerant suction pipe (115) can be formed through the middle of the cylindrical shell (111) and a refrigerant discharge pipe (116) can be formed through the upper cap (112). Accordingly, the refrigerant suction pipe (115) can be connected to the low-pressure portion (110a) of the casing (110) forming the suction space, and the refrigerant discharge pipe (116) can be connected to the high-pressure portion (110b) of the casing (110) forming the discharge space.

[0051] Referring to FIG. 1, the drive motor (120) according to the present embodiment may include a stator (121) and a rotor (122). The stator (121) is fixed to the inner wall surface of a cylindrical shell (111) by hot press fitting, and the rotor (122) may be rotatably provided inside the stator (121).

[0052] The stator (121) may include a stator core (1211) and a stator coil (1212).

[0053] The stator core (1211) is formed in a cylindrical shape and is fixed to the inner surface of the cylindrical shell (111) by hot press fitting. The stator coil (1212) is wound on the stator core (1211) and can be electrically connected to an external power source through a terminal (not shown) that is coupled through the casing (110).

[0054] The rotor (122) may include a rotor core (1221) and a permanent magnet (1222).

[0055] The rotor core (1221) is formed in a cylindrical shape and can be rotatably inserted into the stator core (1211) at a predetermined gap. The permanent magnet (1222) can be embedded in the rotor core (1222) at a predetermined gap along the circumferential direction.

[0056] Additionally, a rotating shaft (125) can be press-fitted and coupled to the center of the rotor core (1221). An eccentric portion (1251) is provided at the top of the rotating shaft (125) so that a pivoting scroll (150), to be described later, can be coupled eccentrically. Accordingly, the rotational force of the drive motor (120) can be transmitted to the pivoting scroll (150) through the rotating shaft (125).

[0057] Additionally, an oil passage (1252) is formed by penetrating the interior of the rotating shaft (125) in the axial direction, and an oil pickup (not shown) for sucking up oil stored in the lower part of the casing (110) may be provided at the bottom of the rotating shaft (125) so as to be in communication with the oil passage (1252). Accordingly, the oil stored in the oil storage space (110c) of the casing (110) is pumped by the oil pickup and sucked up through the oil passage (1252), thereby lubricating the sliding surface.

[0058] Referring to FIG. 1, the main frame (130) according to the present embodiment may include a main flange portion (131) and an axis support portion (132).

[0059] The main flange portion (131) can be fixed in close contact with the inner surface of the cylindrical shell (111). In this case, at least one oil recovery passage (not shown) spaced apart from the inner surface of the cylindrical shell (111) can be formed on the outer surface of the main flange portion (131). Accordingly, oil supplied between the main frame (130) and the rotating scroll (150) can be recovered into the oil storage space (110c) of the casing (110) through the oil recovery passage (not shown).

[0060] Additionally, a scroll fixing surface (1311) is formed on one side of the main flange portion (131), that is, on the edge of the upper surface facing the fixed scroll (140), and an Oldham ring supporting surface (1312) is formed on the inner side of the scroll fixing surface (1311). A plate receiving groove (161) can be formed on the inner side of the Oldham ring supporting surface (1312) to form a back pressure chamber (160a) together with the back pressure plate (162) to be described later. The plate receiving groove (161) will be explained again later together with the back pressure chamber assembly (160).

[0061] The scroll fixing surface (1311) is a part where the fixed scroll (140) is seated and fixed, and can be formed in a stepped shape that is higher than the Oldham ring support surface (1312) and / or the plate receiving groove (161) by a predetermined height. Accordingly, a stepped surface is formed between the inner surface of the scroll fixing surface (1311) and the outer surface of the Oldham ring support surface (1312), and oil flowing into the Oldham ring support surface (1312) and / or the plate receiving groove (161) can be stored in a certain amount on the inside of the scroll fixing surface (1311).

[0062] Although not illustrated in the drawing, the scroll fixing surface (1311) may be formed at the same height as the Oldham ring support surface (1312). In this case, the portion excluding the plate receiving groove (161) on the upper surface of the main flange portion (131) forms a flat plane, thereby allowing the main frame (130) to be easily formed.

[0063] The Oldham ring support surface (1312) is a part on which the Oldham ring (170), to be described later, is seated and slides, and can be formed flat. Accordingly, the Oldham ring (170) is seated on the Oldham ring support surface (1312) and slides smoothly, thereby suppressing the rotation of the rotary scroll (150).

[0064] The plate receiving groove (161) is a portion into which the back pressure plate (162) of the back pressure chamber assembly (160), to be described later, is inserted to slide in the axial direction to form a back pressure chamber, and can be formed lower than the Oldham ring support surface (1312). Accordingly, the back pressure plate (162) of the back pressure chamber assembly (160), to be described later, can move up and down smoothly in the axial direction inside the plate receiving groove (161). The plate receiving groove (161) will be explained again later together with the back pressure plate (162).

[0065] Additionally, a portion of the first back pressure passage (1641), which will be described later, and a portion of the second back pressure passage (1642), which will be described later, may be formed to penetrate the main flange portion (131). For example, a portion of the first back pressure passage and a portion of the second back pressure passage may be formed to penetrate the scroll fixing surface in the axial direction and then be bent to penetrate the bottom surface of the plate receiving groove, respectively. Accordingly, the first back pressure passage and the second back pressure passage may be independently connected to the first back pressure groove and the second back pressure groove, which will be described later.

[0066] Here, the first back pressure passage (1641) passes through the fixed scroll (140) to be described later and is connected to the high-pressure section (110b) of the casing (110), and the second back pressure passage (1642) passes through the fixed scroll (140) to be described later and is connected to a compression chamber (e.g., a compression chamber that forms an intermediate pressure between the suction pressure and the discharge pressure) (V). Accordingly, a discharge pressure can be formed in the first back pressure groove (160a1) connected to the first back pressure passage (1641), and an intermediate pressure can be formed in the second back pressure groove (160a2) connected to the second back pressure passage (1642). The first back pressure passage (1641) and the second back pressure passage (1642) will be described again later together with the back pressure plate.

[0067] Meanwhile, the shaft support protrusion (132) extends from the center of the main flange portion (131) toward the drive motor (120), and a shaft support hole (1321) may be formed on the inner side of the shaft support protrusion (132) by penetrating both axial sides of the main flange portion (131). Accordingly, the main frame (130) can radially support the rotating shaft (125) inserted into the shaft support hole (1321).

[0068] Referring to FIG. 1, the fixed scroll (140) according to the present embodiment can be fixed to the main frame (130) with the pivoting scroll (150), which will be described later, in between. For example, the fixed scroll (140) may include a fixed plate portion (141), a fixed wrap (142), and a fixed side wall portion (143).

[0069] The fixed end plate (141) is formed in the shape of a disc and can be fixed laterally in the low-pressure section (110a) of the casing (110). A discharge port (1411) and a bypass hole (1412) can be formed through the center of the fixed end plate (141) in the axial direction. Accordingly, the refrigerant compressed in the compression chamber (V) can be discharged to the high-pressure section (110b), which is the discharge space, through the discharge port (1411), or discharged to the high-pressure section (110b) through the bypass hole (1412) before reaching the discharge port (1411).

[0070] The fixed wrap (142) can extend from the lower surface of the fixed plate section (141) toward the rotating scroll (150). The fixed wrap (142) can be formed in various shapes, such as an involute. For example, the fixed wrap (142) may be formed as a logarithmic spiral or as a plurality of arc curves.

[0071] However, if the fixed wrap (142) is formed as a logarithmic spiral, the pivot wrap (152) described later must also be formed as a logarithmic spiral, so the shape of the rotation shaft insertion part (153) described later is limited, and the stroke volume can be reduced at the same wrap height and end plate width.

[0072] The fixed wrap (142) according to the present embodiment may be formed such that the wrap curve is formed by connecting a plurality of arcs with different diameters and origins. Accordingly, the wrap thickness of the fixed wrap (142) may be formed differently along the wrap formation direction.

[0073] For example, in the fixed wrap (142) according to the present embodiment, the wrap thickness of the discharge end, which is towards the center, can be formed to be thicker than the wrap thickness of the suction end, which is towards the outermost end. Accordingly, the wrap strength at the discharge end of the fixed wrap (142), which receives a relatively high gas force, can be increased to suppress damage to the fixed wrap (142). In addition, the wrap curve of the fixed wrap (142) is formed wide so that the stroke volume can be expanded at the same wrap height and end plate width. The same applies to the swivel wrap (152) to be described later.

[0074] Additionally, the fixed wrap (142) may be formed with the same wrap height along the wrap formation direction, or may be formed with different heights. In this embodiment, an example is illustrated in which the wrap height of the fixed wrap (142) differs along the wrap formation direction of the fixed wrap (142). For example, in this embodiment, a fixed step surface (1421) is formed in the middle of the fixed wrap (142), so that the wrap height of the discharge end, which is towards the center with respect to the fixed step surface (1421), is formed lower than the wrap height of the suction end, which is towards the outermost edge. Accordingly, the wrap strength at the discharge end of the fixed wrap (142), which receives a relatively high gas force, is increased, thereby suppressing damage to the fixed wrap (142).

[0075] The fixed step surface (1421) can be formed at a position where the compression chamber communicates with the discharge port (1411) at the discharge start time (discharge start point) of the compression chamber (V) that starts discharge relatively earlier among the two compression chambers (V). The same applies to the pivoting step surface (1511) to be described later, which will be explained again later.

[0076] The fixed side wall portion (143) may be formed in an annular shape by extending axially from the edge of the compression surface of the fixed end plate portion (141) to surround the fixed wrap (142). One side of the fixed side wall portion (143) facing the main frame (130) may be placed on and fastened to the scroll support surface (1311) of the main frame (130). Accordingly, the fixed scroll (140) may be supported axially on the main frame (130) and fixed axially.

[0077] Meanwhile, the fixed scroll (140) may have another part of the first back pressure passage (1641) described above and another part of the second back pressure passage formed therein. For example, another part of the first back pressure passage may pass through the fixed end plate and the fixed side wall to communicate with the high-pressure part of the casing, and another part of the second back pressure passage may pass through the fixed end plate and the fixed side wall to communicate with the compression chamber that forms the intermediate pressure. Accordingly, discharge pressure may be formed in the first back pressure groove that communicates with the first back pressure passage, and intermediate pressure may be formed in the second back pressure groove that communicates with the second back pressure passage. The first back pressure passage and the second back pressure passage will be explained again later together with the back pressure plate.

[0078] Referring to FIG. 1, the pivot scroll (150) according to the present embodiment may be coupled to the eccentric portion (1251) of the rotation axis (125) and provided between the main frame (130) and the fixed scroll (140). Specifically, the pivot scroll (150) may include a pivot plate portion (151), a pivot wrap (152), and a rotation axis insertion portion (153).

[0079] The upper surface (hereinafter referred to as the compression surface) of the pivot plate (151) may be formed at a uniform height or partially at a different height. For example, if the pivot shaft insertion part (153) of the pivot plate (151) extends only toward the main frame (130) from the rear surface of the pivot plate (151) facing the main frame (130), the entire pivot plate (151) may be formed at a uniform height. However, if the pivot shaft insertion part (153) is formed to penetrate the pivot plate (151) and overlap radially with the pivot wrap (152) to be described later, the height of the pivot plate (151) may be partially, that is, higher in the part where the pivot shaft insertion part (153) is formed. In this embodiment, an example is illustrated in which the height of the pivot plate (151) at the center is formed higher than the height at the edge. Accordingly, the upper surface (compression surface) of the rotating plate section (151) can be formed such that the discharge side height is higher than the suction side height, centered on the rotating step surface (1511). Through this, the rotation shaft insertion section (153), which will be described later, protrudes in a direction toward the fixed plate section (141), thereby shortening the distance between the first point of application where rotational force acts on the rotating scroll (150) and the second point of application where compressive force acts, and thus reducing the overturning moment of the rotating scroll (150).

[0080] The pivoting step surface (1511) connects the outer surface at the discharge end of the pivoting wrap (152) and the inner surface of the pivoting wrap (152) facing it in a radial direction, and, as with the fixed step surface (1421) mentioned earlier, can be formed at a position where the corresponding compression chamber (V) communicates with the discharge port (1411) at the discharge start time (discharge start point) of the compression chamber (V) adjacent to the discharge port (1411) among the two compression chambers.

[0081] In other words, as the discharge port (1411) is formed as an elongated irregular ellipse, at the point where the rotating step surface (1511) and the fixed step surface (1421) are separated, one end of the rotating step surface (1511) (specifically, the outer side of the rotating wrap) can be formed to be connected to a part of the discharge port (1411) or overlap in the axial direction. Accordingly, at the moment when the rotating step surface (1511) is separated from the fixed step surface (1421) during the rotational movement of the rotating scroll (150), both compression chambers (V) are connected to each other, and at the same time, one compression chamber (V) is connected to the discharge port (1411). Then, even if both compression chambers (V) are connected, the refrigerant in both compression chambers (V) moves to the discharge port (1411) and is discharged together, thereby suppressing compression loss in both compression chambers (V).

[0082] The pivoting wrap (152) can be extended toward the fixed scroll (140) from the upper surface (compression surface) of the pivoting plate section (151). Accordingly, the pivoting wrap (152) can be engaged with the fixed wrap (142) to form two pairs of compression chambers (V).

[0083] The pivoting wrap (152) can be formed in various shapes, such as an involute, to correspond to the fixed wrap (142). For example, the pivoting wrap (152) may be formed as a logarithmic spiral or as a plurality of arc curves.

[0084] However, as previously explained in the fixed wrap (142), when the pivot wrap (152) is formed as a logarithmic spiral, not only is the shape of the rotation shaft insertion part (153) limited, but the stroke volume can also be reduced at the same wrap height and end plate width. Accordingly, the pivot wrap (152) according to the present embodiment can be formed such that the wrap curve is formed by connecting multiple arcs with different diameters and origins, similar to the fixed wrap (142). Accordingly, the pivot wrap (152) can be formed such that the wrap thickness varies along the wrap formation direction, similar to the fixed wrap (142).

[0085] For example, in the present embodiment, the wrapping thickness of the discharge end, which is towards the center, of the swirling wrap (152) may be formed to be thicker than the wrapping thickness of the suction end, which is towards the outermost end. Accordingly, the wrapping strength at the discharge end of the swirling wrap (152), which receives a relatively high gas force, can be increased to suppress damage to the swirling wrap (152). In addition, the wrapping curve of the fixed wrap (142) is formed wide so that the stroke volume can be expanded at the same wrapping height and end plate width.

[0086] The swivel wrap (152) may be formed with the same wrap height along the wrap formation direction, or may be formed with different heights. In this embodiment, an example is shown where the wrap height of the swivel wrap (152) is different along the wrap formation direction. For example, according to this embodiment, the wrap height of the swivel wrap (152) may be formed such that the wrap height of the discharge end, which is towards the center with respect to the swivel step surface (1511), is lower than the wrap height of the suction end, which is towards the outermost edge. Accordingly, the wrap strength at the discharge end of the swivel wrap (152), which receives a relatively high gas force, is increased, thereby suppressing damage to the fixed wrap (142).

[0087] The rotation shaft insertion part (153) is a part to which the eccentric part (1251) of the rotation shaft (125) is coupled. It is formed in a cylindrical shape and may be equipped with an eccentric bearing made of a bushing bearing on its inner surface. For convenience, the bushing bearing is defined as the inner surface of the rotation shaft insertion part (153) in the following description. Accordingly, the inner surface of the rotation shaft insertion part (153) can be understood as substantially referring to the inner surface of the bushing bearing.

[0088] The rotational shaft insertion part (153) may be formed to be located inside the pivoting wrap (152). For example, the inner surface of the rotational shaft insertion part (153) may be formed at a position that overlaps with the discharge end of the pivoting wrap (152) when projected in the axial direction. In other words, the outer surface of the rotational shaft insertion part (153) may be formed to be located on the same circle as the virtual circle connecting the outer surface at the discharge end of the pivoting wrap (152). Accordingly, the inner surface around the discharge end of the pivoting wrap (152) is located inside the outer surface of the rotational shaft insertion part (153), that is, on the front surface of the rotational shaft insertion part (153), as previously described. Then, the rotational shaft insertion part (153) is formed to overlap radially with the pivot wrap (152), and the bearing area of ​​the rotational shaft insertion part (153) is secured wide to stably support the pivot scroll (150), while simultaneously forming a compression chamber (V) on the front end surface of the rotational shaft insertion part (153).

[0089] Meanwhile, at least one lubrication guide groove (1625) may be formed on the back pressure surface (150a) of the rotating scroll (150) that forms the back surface of the rotating plate portion (151), that is, around the rotating shaft insertion portion (153). For example, the lubrication guide groove (1625) may be formed in a circular or arc shape having a predetermined depth, and multiple grooves may be formed on the inner and outer sides, respectively, at predetermined intervals along the circumferential direction, centered on the rotating shaft insertion portion (153). Accordingly, the oil moving from the first back pressure groove (1621a) to the thrust surface (162b) of the back pressure plate (162) through the first oil supply passage (1623a) described later can be rapidly and evenly spread across the entire thrust surface (162b) of the back pressure plate (162) by moving toward the outer side of the back pressure plate (162) by each oil supply guide groove (1625) during the rotational movement of the rotating scroll (150). At the same time, a portion of the oil moving toward the outer side of the back pressure plate (162) by the oil supply guide groove (1625) can be introduced into the second back pressure chamber (160a2) through the second oil supply passage (1623b), thereby allowing the back pressure of the second back pressure chamber (160a2) to be formed rapidly and appropriately. The fuel guide groove (1625) will be explained again later along with the fuel passage (1623a) (1623b).

[0090] FIG. 2 is a perspective view showing the back pressure chamber assembly in FIG. 1 disassembled, FIG. 3 is a plan view showing the back pressure chamber assembly in FIG. 2 assembled, FIG. 4 is a bottom view showing the back pressure chamber assembly in FIG. 2 assembled, and FIG. 5 and FIG. 6 are the "V-V" and "VI-VI" cross-sectional views of FIG. 4.

[0091] Referring to FIGS. 2 to 6, the back pressure chamber assembly (160) according to the present embodiment may be provided on one side of the main frame (130), that is, on the thrust bearing surface (e.g., the inner side of the Oldham ring support surface) (1313) facing the back surface of the slewing scroll (150). Accordingly, the back pressure of the back pressure chamber (160a) (more precisely, the force of the back pressure acting on the back pressure chamber) acts on the slewing scroll (150). In other words, the slewing scroll (150) is pushed in the direction toward the fixed scroll (140) by the back pressure and seals the space between the two compression chambers (V).

[0092] Specifically, the back pressure chamber assembly (160) may include a plate receiving groove (161), a back pressure plate (162), a sealing member (163), and a back pressure passage (164). The plate receiving groove (161) is a space in which the back pressure chamber (160a) is formed, the back pressure plate (162) is a member that varies the volume of the back pressure chamber (160a), the sealing member (163) is a member that seals the back pressure chamber (160a), and the back pressure passage (164) is a passage that supplies oil and / or refrigerant to the back pressure chamber (160a). Accordingly, the back pressure plate (162) forming the back pressure chamber assembly (160) can be inserted into the main frame (130) and move axially to press the pivoting scroll (150) toward the fixed scroll (140).

[0093] Referring to FIG. 2, the plate receiving groove (161) according to the present embodiment may be formed to be recessed to a predetermined depth on the inner side of the Oldham ring support surface (1312) of the main frame (130) facing the pivot scroll (150), as previously described. In other words, the plate receiving groove (161) may be formed such that the inner wall portion (161a) and the outer wall portion (161b) are spaced apart by a predetermined radial distance. For example, the inner wall portion (161a) of the plate receiving groove (161) may be formed such that its surface is spaced apart from the inner surface of the shaft support hole (1321) by a sealing distance, and is formed to be as close as possible to the inner surface of the shaft support hole (1321). The outer wall portion (161b) of the plate receiving groove (161) may be formed such that its surface is spaced apart from the outer surface of the main flange portion (131) by a sealing distance, and is as close as possible to the outer surface of the main flange portion (131). Accordingly, the radial width of the plate receiving groove (161) is formed as wide as possible, and the area of ​​the back pressure chamber (160a) is increased so that the rotating scroll (150) can be stably supported.

[0094] The plate receiving groove (161) can be formed in an annular shape, with the inner wall portion (161a) and the outer wall portion (161b) each forming a circle. Accordingly, a back pressure plate (162), which will be described later, can be inserted into the interior of the plate receiving groove (161), and a back pressure chamber (160a) can be formed together with the back pressure plate (162).

[0095] In this case, a third sealing member (1633), to be described later, may be inserted into the bottom surface connecting the inner wall portion (161a) and the outer wall portion (161b) of the plate receiving groove (161) to seal the space between the first back pressure groove (1621a) and the second back pressure groove (1621b) of the back pressure plate (162), to be described later. Accordingly, the back pressure chamber (160a) may be formed by separating it into a first back pressure chamber (160a1) on the inner side and a second back pressure chamber (160a2) on the outer side.

[0096] Referring to FIGS. 2 to 6, the back pressure plate (162) according to the present embodiment can be inserted into the plate receiving groove (161) of the main frame (130) so as to slide in the axial direction of the rotation axis (125). For example, the inner surface of the back pressure plate (162) can be formed to slide in contact with the inner wall portion (161a) of the plate receiving groove (161), and the outer surface of the back pressure plate (162) can be formed to slide in contact with the outer wall portion (161b) of the plate receiving groove (161). Accordingly, the inner surface and the outer surface of the back pressure plate (162) are each formed in an annular shape so as to slide into the inner wall portion (161a) and the outer wall portion (161b) of the plate receiving groove (161).

[0097] Specifically, the back pressure plate (162) may include a back pressure portion (1621) and a thrust portion (1622). The back pressure portion (1621) is a part that forms a back pressure chamber (160a) together with the plate receiving groove (161), and the thrust portion (1622) is a part that forms a thrust bearing surface together with the back surface of the pivot scroll (150).

[0098] The back pressure section (1621) is formed in an annular shape as described above, but the cross-sectional area of ​​the back pressure section (1621) may be formed larger than the cross-sectional area of ​​the thrust section (1622) to be described later. For example, the inner diameter (D11) of the back pressure section (1621) may be formed to be equal to or smaller than the inner diameter (D21) of the thrust section (1622), and the outer diameter (D12) of the back pressure section (1621) may be formed larger than the outer diameter (D22) of the thrust section (1622). Accordingly, the back pressure surface (162a) of the back pressure plate (162) is formed wider than the thrust surface (162b) of the back pressure plate (162), and the back pressure area for the pivoting scroll (150) can be expanded widely.

[0099] In this case, the back pressure portion (1621) may be formed such that the back pressure surface (162a) of the back pressure plate (162) facing the plate receiving groove (161) is formed flat, and a first back pressure groove (1621a) forming the first back pressure chamber (160a1) may be formed on the inner side, and a second back pressure groove (1621b) forming the second back pressure chamber (160a2) may be formed on the outer side, each in an annular shape. In other words, the first back pressure groove (1621a) and the second back pressure groove (1621b) may be formed spaced apart by a predetermined interval in the radial direction with a sealing projection (1621c) placed between the two back pressure grooves (1621a) (1621b). Accordingly, on one side of the back pressure portion (1621) forming the back pressure surface (162a) of the back pressure plate (162), a first back pressure groove (1621a) and a second back pressure groove (1621b) may be formed separately along the radial direction.

[0100] In addition, in this case, sealing members (1631) and (1632) may be provided on the inner and outer surfaces of the back pressure plate (162), respectively. For example, a first sealing member (1631) may be provided on the inner surface of the back pressure portion (1621) facing the inner wall portion (161a) of the plate receiving groove (161), a second sealing member (1632) may be provided on the outer surface of the back pressure portion (1621) facing the outer wall portion (161b) of the plate receiving groove (161), and a third sealing member (1633) may be provided on the bottom surface (hereinafter, back pressure surface) of the plate receiving groove (161) facing the sealing projection (1621c) of the back pressure plate (162). Accordingly, the first back pressure chamber (160a1) can be sealed by the first sealing member (1631) and the third sealing member (1633), and the second back pressure chamber (160a2) can be sealed by the second sealing member (1632) and the third sealing member (1633), respectively.

[0101] Referring to FIGS. 1, 4 to 6, the first back pressure groove (1621a) may be formed by including the inner circumferential edge of the back pressure portion (1621). For example, the first back pressure groove (1621a) may be formed by chamfering the inner circumferential edge of the back pressure portion (1621). In other words, the first back pressure groove (1621a) may be formed such that at least a portion is located closer to the center than the pivoting step surface (1511) when projected in the axial direction. Accordingly, the back pressure area of ​​the first back pressure groove (1621a) is formed as wide as possible, and at least a portion of the first back pressure chamber (160a1) may be located closer to the center than the pivoting step surface (1511) when projected in the axial direction, thereby overlapping axially with the compression chamber (e.g., the final compression chamber connected to the discharge port) (V) which forms a relatively high pressure. Through this, the center of the rotating scroll (150) that receives a relatively high compressive force among the rotating scrolls (150) can be stably supported, thereby effectively blocking leakage between the compression chambers (V).

[0102] Additionally, the second back pressure groove (1621b) may be formed to be located outside the pivoting step surface (1511) when projected axially. Accordingly, at least a portion of the second back pressure chamber (160a2) may be located outside the pivoting step surface (1511) when projected axially, so that it may overlap with the low-pressure side compression chamber (e.g., the compression chamber forming intermediate pressure) (V) that forms a relatively low pressure. Through this, the edge of the pivoting scroll (150) that receives a relatively low compression force among the pivoting scrolls (150) can be supported with an appropriate back pressure, thereby effectively suppressing the fixed scroll (140) and the pivoting scroll (150) from being in close contact with each other.

[0103] Although not illustrated in the drawing, the first back pressure groove (1621a) and the second back pressure groove (1621b) may be formed on the bottom surface (back pressure surface) of the plate receiving groove (161) facing the back pressure surface (162a) of the back pressure plate (162), or they may be formed in parts on the back pressure surface (162a) of the back pressure plate (162) and the bottom surface of the main frame (130) facing each other. In the former case, the depth of the first back pressure groove and the second back pressure groove can be formed deeper to expand the volume of the back pressure chamber, and in the latter case, the weight of the back pressure plate can be reduced while expanding the volume of the back pressure chamber.

[0104] Additionally, although not shown in the drawing, only one back pressure groove (not shown) may be formed. In this case, the back pressure groove may be connected to the high-pressure section (110b) of the casing (110) or to the intermediate compression chamber (V) through a single back pressure passage (not shown).

[0105] Referring to FIGS. 2 to 6, the thrust portion (1622) according to the present embodiment may be formed to extend annularly toward the pivot scroll (150) from the other side of the back pressure portion (1621), for example, from the back side of the back pressure portion (1621). In other words, the thrust portion (1622) may be formed annularly as described above, but the inner diameter (D21) of the thrust portion (1622) may be larger than or equal to the inner diameter (D11) of the back pressure portion (1621), and the outer diameter (D22) of the thrust portion (1622) may be formed smaller than the outer diameter (D12) of the back pressure portion (1621). Accordingly, the axial cross-sectional area of ​​the thrust section (1622) is formed to be smaller than the axial cross-sectional area of ​​the back pressure section (1621), thereby reducing the friction area between the thrust section (1622) and the rotating scroll (150) and minimizing friction loss.

[0106] In this case, a drainage passage (1625) connecting the inner surface and the outer surface of the thrust portion (1622) may be formed in the thrust portion (1622). Accordingly, a portion of the oil sucked in through the oil passage (1252) of the rotating shaft (125) can move quickly toward the Oldham ring support surface (1312) of the main frame (130) through the drainage passage (1625) to smoothly lubricate the Oldham ring (170) and the rotating scroll (150).

[0107] For example, the drainage passage (1625) may be formed as a hole penetrating from the inner surface to the outer surface of the back pressure plate (specifically the thrust portion), or it may be formed as a groove extending between the inner surface and the outer surface of the back pressure plate (specifically the thrust portion) by being recessed to a predetermined depth from the thrust surface (162b) of the back pressure plate (162) facing the rotating scroll (150). In the former case, the drainage passage (1625) is formed as close as possible to the rotating shaft insertion part (153) so that oil can be quickly supplied to the Oldham ring (170), and in the latter case, the oil passing through the drainage passage (1625) moves toward the Oldham ring (170) while lubricating the thrust surface (162b) of the back pressure plate (162), thereby further reducing friction loss between the back pressure plate (162) and the rotating scroll (150). This embodiment illustrates the former case, that is, an example in which the drainage passage (1625) penetrates between the inner surface and the outer surface of the thrust part (1622).

[0108] Referring to FIGS. 2 to 6, the back pressure plate (162) according to the present embodiment may further include a lubrication passage (1623a) (1623b) penetrating between the back pressure surface (162a) and the thrust surface (162b) of the back pressure plate (162). The lubrication passage (1623a) (1623b) may be formed penetrating between the back pressure surface (162a) and the thrust surface (162b) of the back pressure plate (162). For example, the lubrication passage (1623a) (1623b) may be formed penetrating along the axial direction or inclined between the back pressure surface (162a) and the thrust surface (162b) of the back pressure plate (162). In the former case, the lubrication passages (1623a) (1623b) can be easily formed, and in the latter case, even if the oil pressure is relatively low, it can move smoothly through the inclined lubrication passages. This embodiment illustrates the former case, that is, an example in which the lubrication passages (1623a) (1623b) are formed along the axial direction.

[0109] Specifically, the supply passage (1623a) (1623b) may include a first supply passage (1623a) and a second supply passage (1623b). The first supply passage (1623a) is a hole penetrating between the first back pressure groove (1621a) and the thrust surface (162b) of the back pressure plate (162), and the second supply passage (1623b) is a hole penetrating between the second back pressure groove (1621b) and the thrust surface (162b) of the back pressure plate (162). Accordingly, the first supply passage (1623a) may be formed on the inner side of the back pressure plate (162), and the second supply passage (1623b) may be formed on the outer side of the back pressure plate (162).

[0110] As previously described, the first lubrication passage (1623a) can be formed to communicate axially with the first back pressure groove (1621a). For example, one end of the first lubrication passage (1623a) can be formed to penetrate into the interior of the first back pressure groove (1621a), and the other end of the first lubrication passage (1623a) can be formed to penetrate into the thrust surface (162b) of the back pressure plate (162). Accordingly, oil flowing into the first back pressure groove (1621a) moves through the first lubrication passage (1623a) to the thrust surface (162b) of the back pressure plate (162) and lubricates the thrust surface (162b) of the back pressure plate (162).

[0111] In this case, the first oil passage (1623a) may be formed with the same cross-sectional area between both ends, or, depending on the case, may be formed with different cross-sectional areas. In the former case, processing of the first oil passage (1623a) is easy, and in the latter case, the inner diameter of the other end of the first oil passage (1623a) is formed smaller so that the pressure of the oil flowing between the back pressure surface (162a) of the rotating scroll (150) and the thrust surface (162b) of the back pressure plate (162) can be appropriately reduced. This embodiment illustrates the former case, that is, an example where the inner diameter of the first oil passage (1623a) is the same.

[0112] In addition, in this case, the first supply passage (1623a) may be formed in multiple numbers at predetermined intervals along the circumferential direction, and the multiple first supply passages (1623a) may be formed at equal intervals along the circumferential direction. Accordingly, oil flowing into the thrust surface (162b) of the back pressure plate (162) through the first supply passage (1623b) is uniformly dispersed and moved to each second supply passage (1623b), thereby evenly lubricating the thrust surface (162b) of the back pressure plate (162).

[0113] In addition, in this case, the total cross-sectional area of ​​the first supply passage (1623a) may be formed to be smaller than or equal to the total cross-sectional area of ​​the second supply passage (1623b) to be described later, preferably smaller. For example, the first supply passage (1623a) and the second supply passage (1623b) may each be formed in multiple numbers at predetermined intervals along the circumferential direction, but the number of the first supply passage (1623a) may be formed to be smaller than the number of the second supply passage (1623b). Accordingly, oil leakage in the first back pressure groove (1621a), which forms a relatively high pressure, can be minimized as much as possible, thereby maintaining a high back pressure in the first back pressure groove (1621a).

[0114] Although not illustrated in the drawing, the number of first supply passages (1623a) may be formed to be greater than or equal to the number of second supply passages (1623b). In this case, the cross-sectional area of ​​each first supply passage (1623a) may be formed to be smaller than the cross-sectional area of ​​each second supply passage (1623b). Even in this case, oil leakage in the first back pressure groove (1621a) can be minimized as much as possible to maintain a high back pressure in the first back pressure groove (1621a).

[0115] As previously described, the second supply passage (1623b) can be formed to be axially connected to the second back pressure groove (1621b). For example, one end of the second supply passage (1623b) can be formed to be connected to the interior of the second back pressure groove (1621b), and the other end of the second supply passage (1623b) can be formed to be connected to the thrust surface (162b). Accordingly, a portion of the oil flowing into the thrust surface (162b) of the back pressure plate (162) through the first supply passage (1623a) can be flowed into the second back pressure groove (1621b) through the second supply passage (1623b), thereby rapidly increasing the back pressure of the second back pressure chamber (160b) containing the second back pressure groove (1621b).

[0116] In this case, the second supply passage (1623b) may be formed with the same cross-sectional area between both ends, or, depending on the case, with different cross-sectional areas. In the former case, processing of the second supply passage (1623b) is easy, and in the latter case, the inner diameter of the other end of the second supply passage (1623b) may be formed larger so that oil can flow smoothly into the second back pressure groove (1621b) through the second supply passage (1623b). This embodiment illustrates the former case, that is, an example where the inner diameter of the second supply passage (1623b) is the same.

[0117] In addition, in this case, the second supply passage (1623b) may be formed in multiple numbers at predetermined intervals along the circumferential direction, and the multiple second supply passages (1623b) may be formed at equal intervals along the circumferential direction. Accordingly, oil flowing into the thrust surface (162b) of the back pressure plate (162) through the first supply passage (1623b) is uniformly dispersed and moved to each second supply passage (1623b), thereby evenly lubricating the thrust surface (162b) of the back pressure plate (162).

[0118] In addition, in this case, at least some of the multiple second-class passages (1623b) may be formed to be located on different lines in the radial direction from the first-class passage (1623a). For example, when four first-class passages (1623a) and eight second-class passages (1623b) are formed, four of the eight second-class passages (1623b) may be formed to be located on a straight line in the radial direction from the first-class passage (1623a), and the remaining four may be formed to be located on a virtual line in the radial direction between the first-class passages (1623a). Accordingly, the second-class passages (1623b) located between the first-class passages (1623a) are located relatively far from the first-class passages (1623a). Then, some of the oil flowing into the thrust surface (162b) of the back pressure plate (162) moves toward the second supply passage (1623b), which is located relatively far from the first supply passage (1623a), thereby widely lubricating the thrust surface (162b) of the back pressure plate (162).

[0119] Although not illustrated in the drawing, multiple second supply passages (1623b) may be formed to be located in a straight line in the radial direction with each of the multiple first supply passages (1623a). In this case, the multiple second supply passages (1623b) may be located at the shortest distance from the multiple first supply passages (1623a). Accordingly, oil flowing into the thrust surface (162b) of the back pressure plate (162) through the multiple first supply passages (1623a) can move rapidly to the second back pressure chamber (160a2) through the multiple second supply passages (1623b) to smoothly form the outer back pressure.

[0120] Meanwhile, referring to FIG. 2, a plurality of lubrication guide grooves (1625) may be formed on the back surface of the rotating scroll (150) facing the thrust surface (162b) of the back pressure plate (162), that is, on the back pressure surface (162a) of the rotating scroll (150). For example, the lubrication guide grooves (1625) may be formed such that an inner lubrication guide groove and an outer lubrication guide groove are alternately positioned along the circumferential direction. Accordingly, the number of lubrication guide grooves (1625) can be minimized, and the oil that has moved between the back pressure surface (162a) of the rotating scroll (150) and the thrust surface (162b) of the back pressure plate (162) through the first lubrication passage (1623a) can be smoothly moved to the outer side of the back pressure plate (162), that is, to the Oldham ring (170) and / or the second lubrication passage (1623b).

[0121] Referring to FIG. 2, the sealing member (163) according to the present embodiment is provided between the plate receiving groove (161) and the back pressure plate (162) to seal the back pressure chamber (160a), and may include a first sealing member (1631), a second sealing member (1632), and a third sealing member (1633). The first sealing member (1631) is provided on the inner side of the back pressure chamber (160a), the second sealing member (1632) is provided on the outer side of the back pressure chamber (160a), and the third sealing member (1633) may be provided between the first back pressure chamber (160a1) and the second back pressure chamber (160a2).

[0122] Specifically, the first sealing member (1631) is provided between the inner wall portion (161a) of the plate receiving groove (161) and the inner surface of the back pressure plate (162) facing it in the radial direction, the second sealing member (1632) is provided between the outer wall portion (161b) of the plate receiving groove (161) and the outer surface of the back pressure plate (162) facing it in the radial direction, and the third sealing member (1633) can be provided between the back pressure surface (162a) of the plate receiving groove (161) and the sealing projection (1623c) of the back pressure plate (162) facing it in the axial direction. Accordingly, the first sealing member (1631) separates the inner side of the first back pressure chamber (160a1), and the second sealing member (1632) separates the outer side of the second back pressure chamber (160a2) from the internal space (more precisely, the low-pressure portion forming the suction space) (110a) of the casing (110), and the third sealing member (1633) can separate the first back pressure chamber (160a1) and the second back pressure chamber (160a2).

[0123] For example, the first sealing member (1631) may be made of an O-ring and inserted into and fixed in a first sealing groove (not shown) provided on the inner circumference of the back pressure plate (162). Accordingly, the thickness of the inner wall portion (161a) of the plate receiving groove (161) can be formed as thin as possible, thereby forming the inner circumference area of ​​the first back pressure chamber (160a1) as wide as possible. Through this, the center side of the rotating scroll (150) that forms the discharge pressure can be effectively supported.

[0124] The second sealing member (1632) is made of an O-ring and can be inserted into and fixed in a second sealing groove (not shown) provided on the outer surface of the back pressure plate (162). Accordingly, the assembly of the second sealing member (1632) can be improved.

[0125] The third sealing member (1633) is made of an O-ring and can be inserted and fixed into the third sealing groove (not shown) provided on the back pressure surface (162a), which is the bottom surface of the plate receiving groove (161). Accordingly, the width of the sealing projection (1621c) of the back pressure plate (162) can be formed as small as possible, thereby making the area of ​​the first back pressure groove (1621a) and the area of ​​the second back pressure groove (1621b) as large as possible.

[0126] Referring to FIGS. 2 to 6, the back pressure passage (164) according to the present embodiment is connected between the compression chamber (V) and the back pressure chamber (160a) and may include a first back pressure passage (1641) and a second back pressure passage (1642). The first back pressure passage (1641) is provided between the high-pressure section (110b) of the casing (110) forming the discharge space and the first back pressure chamber (160a1), and the second back pressure passage (1642) may be provided between the compression chamber (V) forming an intermediate pressure between the discharge pressure and the suction pressure and the second back pressure chamber (160a2).

[0127] Referring to FIGS. 3 to 5, the first back pressure passage (1641) can be formed to penetrate the fixed end plate portion (141) and fixed side wall portion (143) of the fixed scroll (140), and the main flange portion (131) of the main frame (130), and to penetrate the back pressure surface (162a) of the plate receiving groove (161) provided in the main flange portion (131). In other words, one end of the first back pressure passage (1641) can penetrate the back surface of the fixed end plate portion (141) and be connected to the high pressure portion (110b) of the casing (110) that forms the discharge space, and the other end of the first back pressure passage (1641) can penetrate the main flange portion (131) of the main frame (130) and be connected to the first back pressure groove (1621a) of the back pressure plate (162). Accordingly, a portion of the oil discharged to the high-pressure section (110b) of the casing (110) forming the discharge space can flow into the first back pressure groove (1621a) through the first back pressure passage (1641) to form back pressure of the discharge pressure (high pressure).

[0128] Although not illustrated in the drawing, an oil guide groove (not shown) may be formed on the back of the fixed scroll (140) so that oil separated from the high-pressure section (110b) is collected into the first back pressure hole (1641). Accordingly, the oil separated from the high-pressure section (110b) can be quickly collected into the first back pressure hole (1641) and move more quickly to the first back pressure chamber (160a1).

[0129] Referring to FIGS. 3 to 5, the second back pressure passage (1642) can be formed to penetrate the fixed end plate portion (141) and fixed side wall portion (143) of the fixed scroll (140), and the main flange portion (131) of the main frame (130), and to penetrate the back pressure surface (162a) of the plate receiving groove (161) provided in the main flange portion (131). In other words, one end of the second back pressure passage (1642) can penetrate the compression surface of the fixed end plate portion (141) facing the rotating scroll (150) and be connected to the compression chamber (V) that forms the intermediate pressure, and the other end of the second back pressure passage (1642) can penetrate the main flange portion (131) of the main frame (130) and be connected to the second back pressure groove (1621b) of the back pressure plate (162). Accordingly, a portion of the refrigerant compressed in the compression chamber (V) forming the intermediate pressure can flow into the second back pressure groove (1621b) through the second back pressure passage (1642) to form the back pressure of the intermediate pressure (low pressure).

[0130] The unexplained symbol 118 in the drawing is a subframe.

[0131] The effects of the scroll compressor according to the above embodiment are as follows.

[0132] That is, when power is applied to the drive motor (120) and rotational force is generated, the pivoting scroll (150), which is eccentrically coupled to the rotation shaft (125), pivots relative to the fixed scroll (140) by the Oldham ring (170). At this time, two pairs of compression chambers (V) that move continuously are formed between the fixed scroll (140) and the pivoting scroll (150).

[0133] Then, as the rotating scroll (150) moves from the intake port (or intake chamber) (1411) toward the discharge port (or discharge chamber) (1412), the volume of both compression chambers (V) gradually decreases.

[0134] Then, the refrigerant is sucked into the low-pressure section (110a) of the casing (110) through the refrigerant suction pipe (117), and a portion of this refrigerant is immediately sucked into and compressed in each suction pressure chamber (not labeled) forming both compression chambers (V), while the remaining refrigerant moves toward the drive motor (120) to cool the drive motor (120) and is then sucked into the suction pressure chamber (not labeled) together with other refrigerants.

[0135] Then, this refrigerant is compressed while moving along the path of both compression chambers (V), and this refrigerant is discharged to the high-pressure part (110b) of the casing (110) through the discharge port (1411) of the fixed scroll (140) in the final compression chamber formed closer to the center than the pivoting step surface (1511) of the pivoting scroll (150).

[0136] At this time, oil is separated from the refrigerant discharged to the high-pressure section (110b) and flows into the first back pressure chamber (160a1), and a portion of the refrigerant compressed in the compression chamber (V) flows into the second back pressure chamber (160a2), and these oil and refrigerants form back pressure in each back pressure chamber (160a1) (160a2) and pressurize the rotating scroll (150) toward the fixed scroll (140) to suppress leakage between the compression chambers (V).

[0137] FIG. 7 is a cross-sectional view shown to explain the effects of the back pressure chamber assembly according to the present embodiment.

[0138] Referring to FIG. 7, as previously described, a portion of the oil separated from the refrigerant discharged to the high-pressure section (110b) moves from the high-pressure section (110b) to the first back pressure chamber (160a1) through the first back pressure passage (1641) that continuously passes through the fixed scroll (140) and the main frame (130).

[0139] Then, the first back pressure chamber (160a1) forms a back pressure of the discharge pressure to support the center side of the rotating scroll (150) with a high back pressure. Accordingly, as the center side of the rotating scroll (150) is closely attached to the fixed scroll (140), it becomes possible to effectively block the leakage of the refrigerant from the high-pressure side compression chamber (V) to the low-pressure side compression chamber (V).

[0140] Additionally, a portion of the refrigerant compressed in the compression chamber (V) moves from the intermediate compression chamber (V) to the second back pressure chamber (160a2) through the second back pressure passage (1642). In other words, a portion of the refrigerant compressed in the compression chamber (V) moves from the compression chamber (V) to the second back pressure chamber (160a2) through the second back pressure passage (1642) in an intermediate pressure state before reaching the discharge port (1411).

[0141] Then, the second back pressure chamber (160a2) forms a back pressure of medium pressure to support the outer side of the rotating scroll (150) with a low back pressure. Accordingly, the outer side of the rotating scroll (150) is in relatively weak contact with the fixed scroll (140), thereby reducing friction loss between the fixed scroll (140) and the rotating scroll (150).

[0142] At the same time, as shown in FIG. 7, the oil in the first back pressure chamber (160a1) moves through the first lubrication passage (1623a) between the back pressure surface (150a) of the rotating scroll (150) and the thrust surface (162b) of the back pressure plate (162) to lubricate the space between the rotating scroll (150) and the back pressure plate (162). Accordingly, friction loss between the rotating scroll (150) and the back pressure plate (162) can be suppressed.

[0143] High-pressure oil flowing into the first back pressure chamber (160a1) through the first back pressure passage (1641) moves through the first lubrication passage (1623a) to the thrust surface (162b) of the back pressure plate (162) facing the rotating end plate (151), and this oil lubricates the space between the back pressure surface (150a) of the rotating scroll (150) and the thrust surface (162b) of the back pressure plate (162) by spreading through the lubrication guide groove (1625) provided on the back surface of the rotating end plate (151) of the rotating scroll (150), for example, the back pressure surface (162a) of the rotating scroll (150) during the rotational movement of the rotating scroll (150). Accordingly, energy efficiency can be increased by reducing friction loss between the rotating scroll (150) and the back pressure plate (162).

[0144] At this time, a portion of the oil diffusing from the thrust surface (162b) of the back pressure plate (162) flows into the second back pressure chamber (160a2) through the second supply passage (1623b) to form back pressure in the second back pressure chamber (160a2). Accordingly, back pressure in the second back pressure chamber (160a2) is rapidly formed, thereby more effectively suppressing leakage between the compression chambers (V).

[0145] In this way, as the back pressure chamber assembly is positioned between the main frame and the slewing scroll, the number of parts and / or assembly steps constituting the back pressure chamber assembly can be reduced. This allows for a reduction in the number of parts of the back pressure chamber assembly, thereby increasing the compression efficiency of the scroll compressor while lowering manufacturing costs.

[0146] In addition, as the back pressure chamber assembly is inserted into and coupled to the main frame, leakage of the refrigerant from the back pressure chamber to the low-pressure section of the casing can be suppressed even if the behavior of the slewing scroll is unstable. This prevents the refrigerant in the back pressure chamber from heating the suction refrigerant in the low-pressure section, thereby preventing a decrease in compression efficiency caused by suction loss.

[0147] In addition, since a back pressure chamber assembly forming a back pressure chamber is provided in the main frame, the actual area of ​​the back pressure chamber can be secured as wide as possible. Through this, the back pressure area supporting the slewing scroll is expanded, allowing the slewing scroll to be supported stably.

[0148] In addition, as a lubrication passage connecting the back pressure surface and the thrust surface is formed in the back pressure plate constituting the back pressure chamber assembly, a portion of the oil flowing into the back pressure chamber can be rapidly supplied to the thrust surface between the slewing scroll and the back pressure plate. This allows for increased energy efficiency by expanding the area of ​​the back pressure chamber while reducing frictional losses between the back pressure chamber assembly and the slewing scroll.

[0149] In addition, as the back pressure chamber is connected to the high-pressure section forming the discharge space as well as the compression chamber forming the intermediate pressure, it is possible to form a high back pressure on the discharge side while simultaneously lowering the back pressure on the intermediate pressure side. Through this, leakage between the compression chambers on the discharge side can be effectively suppressed, and excessive contact between the scrolls on the suction side can be suppressed, thereby further increasing the compression efficiency of the scroll compressor.

[0150] In addition, as the rotating shaft insertion part is formed to overlap radially with the slewing wrap, and a portion of the slewing wrap is extended from the leading edge of the rotating shaft insertion part, a compression chamber can also be formed in the center of the slewing scroll (or fixed scroll). Through this, the compression ratio increases as the compression cycle of the compression chamber lengthens while the rotating shaft insertion part extends toward the slewing wrap, thereby improving volumetric efficiency. At the same time, the wrap height at the discharge end of the slewing wrap is lowered and the wrap thickness is increased, which increases the wrap strength of the slewing wrap and suppresses wrap breakage. The same applies to the fixed wrap.

[0151] Meanwhile, other embodiments of the back pressure chamber assembly are as follows.

[0152] That is, in the above-described embodiment, the total cross-sectional area of ​​the first-class circulation passage is formed to be smaller than the total cross-sectional area of ​​the second-class circulation passage, but in some cases, the total cross-sectional area of ​​the first-class circulation passage and the total cross-sectional area of ​​the second-class circulation passage may be formed to be the same, or the total cross-sectional area of ​​the first-class circulation passage may be formed to be larger than the total cross-sectional area of ​​the second-class circulation passage.

[0153] FIG. 8 is a perspective view showing another embodiment of the back pressure plate in the back pressure chamber assembly.

[0154] The basic configuration of the back pressure chamber assembly (160) including the back pressure plate (162) according to the present embodiment and the resulting effects may be similar to the previously described embodiment. For example, a plate receiving groove (161) that is recessed to a predetermined depth is formed in the main flange portion (131) of the main frame (130) facing the back pressure surface (150a) of the rotating scroll (150), and a back pressure plate (162) that presses the rotating scroll (150) toward the fixed scroll (140) can be inserted axially into the plate receiving groove (161). Accordingly, the back pressure area that presses the rotating scroll (150) toward the fixed scroll (140) is expanded while maintaining the rotating back pressure method, thereby allowing the rotating scroll (150) to be stably supported.

[0155] Additionally, a plurality of first supply passages (1623a) may be formed on the central side of the back pressure plate (162) to connect a first back pressure groove (1621a), which communicates with the high-pressure section (110b) of the casing (110) that is the discharge space, to the thrust surface (162b), and a plurality of second supply passages may be formed on the outer side of the back pressure plate (162) to connect a second back pressure groove, which communicates with the intermediate compression chamber, to the thrust surface. Accordingly, oil separated from the refrigerant in the high-pressure section may flow into the thrust surface of the back pressure plate (162) through the plurality of first supply passages (1623a) to smoothly lubricate the thrust surface of the back pressure plate (162) and the back pressure surface of the rotating scroll facing it.

[0156] However, in this embodiment, the first flow passage (1623a) and the second flow passage (1623b) are each formed as holes with the same inner diameter at both ends, and the total cross-sectional area of ​​the first flow passage (1623a) and the total cross-sectional area of ​​the second flow passage (1623b) may be formed to be the same.

[0157] Referring to FIG. 8, the first lubrication passage (1623a) and the second lubrication passage (1623b) are formed as holes having the same cross-sectional area, and the number of the first lubrication passage (1623a) and the number of the second lubrication passage (1623b) can be formed to be the same. Accordingly, the total cross-sectional area of ​​the first lubrication passage (1623a) is increased, thereby increasing the lubrication effect on the thrust surface in the center of the back pressure plate (162) that receives a relatively high compressive force.

[0158] In this case, at least some of the plurality of first supply passages (1623a) and the plurality of second supply passages may be formed to be located on different lines in the radial direction. For example, if the first supply passages (1623a) and the second supply passages are each formed in equal numbers, each second supply passage may be formed to be located on a virtual line passing through the middle of the circumferential direction of each first supply passage (1623a). In other words, the first supply passages (1623a) and the second supply passages may be formed to be located in a zigzag shape. Accordingly, the plurality of first supply passages (1623a) are located far from the plurality of second supply passages (1623b), thereby allowing the thrust surface (162b) of the back pressure plate (162) to be lubricated more widely.

[0159] Although not illustrated in the drawing, a plurality of first supply passages (1623a) and a plurality of second supply passages may each be formed to overlap in the radial direction. For example, a plurality of first supply passages (1623a) and a plurality of second supply passages may be formed in equal numbers, but each may be formed to be located on the same line in the radial direction. In this case, oil flowing into the thrust surface (162b) of the back pressure plate (162) through the first supply passage (1623a) can be rapidly moved to the second back pressure groove (1621b), thereby rapidly increasing the back pressure of the second back pressure chamber including the second back pressure groove.

[0160] Meanwhile, other embodiments of the back pressure chamber assembly are as follows.

[0161] That is, in the above-described embodiment, the total cross-sectional area of ​​the first-class circulation passage is formed to be smaller than the total cross-sectional area of ​​the second-class circulation passage, but in some cases, the total cross-sectional area of ​​the first-class circulation passage may be formed to be larger than the total cross-sectional area of ​​the second-class circulation passage.

[0162] FIGS. 9 and FIGS. 10 are perspective views showing other embodiments of the back pressure plate in the back pressure chamber assembly.

[0163] The basic configuration of the back pressure chamber assembly (160) including the back pressure plate (162) according to the present embodiment and the resulting effects may be similar to the previously described embodiment. For example, a plate receiving groove (161) that is recessed to a predetermined depth is formed in the main flange portion (131) of the main frame (130) facing the back pressure surface (150a) of the rotating scroll (150), and a back pressure plate (162) that presses the rotating scroll (150) toward the fixed scroll (140) can be inserted axially into the plate receiving groove (161). Accordingly, the back pressure area that presses the rotating scroll (150) toward the fixed scroll (140) is expanded while maintaining the rotating back pressure method, thereby allowing the rotating scroll (150) to be stably supported.

[0164] Additionally, a plurality of first supply passages (1623a) may be formed on the central side of the back pressure plate (162) to connect a first back pressure groove (1621a) to the high-pressure portion (110b) of the casing (110), which is the discharge space, to the thrust surface (162b), and a plurality of second supply passages (1623b) may be formed on the outer side of the back pressure plate (162) to connect a second back pressure groove (1621b) to the thrust surface (162b) which is connected to the intermediate compression chamber (V). Accordingly, oil separated from the refrigerant in the high-pressure section (110b) flows into the thrust surface (162b) of the back pressure plate (162) through a plurality of first supply passages (1623a), thereby smoothly lubricating the thrust surface (162b) of the back pressure plate (162) and the back pressure surface (150b) of the rotating scroll (150) facing it.

[0165] However, in this embodiment, the total cross-sectional area of ​​the first flow passage (1623a) may be formed to be larger than the total cross-sectional area of ​​the second flow passage. Accordingly, the total cross-sectional area of ​​the first flow passage (1623a) is further increased, thereby further enhancing the lubrication effect on the thrust surface in the center of the back pressure plate (162) that receives a relatively high compressive force.

[0166] Referring to FIGS. 9 and 10, the first lubrication passage (1623a) according to the present embodiment may include a lubrication hole (1623a1) and a lubrication groove (1623a2). The lubrication hole (1623a1) is a portion penetrating the back pressure plate (162), and the lubrication groove (1623a2) is a portion formed on the thrust surface (162b) of the back pressure plate (162).

[0167] The lubrication hole (1623a1) can be formed in almost the same way as the first lubrication passage (1623a) described above. For example, the lubrication hole (1623a1) is formed by penetrating the back pressure plate (162) in the axial direction, and one end of the lubrication hole (1623a1) can be connected to the first back pressure groove (1621a), and the other end of the lubrication hole (1623a1) can be connected to the lubrication groove (1623a2). Accordingly, oil flowing into the first back pressure groove (1621a) can move to the lubrication groove (1623a2) through the lubrication hole (1623a1).

[0168] The lubrication groove (1623a2) may be formed in an arc shape so that the lubrication hole (1623a1) is individually connected. For example, the lubrication groove (1623a2) may be formed in a plurality of arc shapes as shown in FIG. 9, and may be formed so that one lubrication groove (1623a2) accommodates one lubrication hole (1623a1). In this case, the cross-sectional area of ​​the lubrication groove (1623a2) may be formed larger than the cross-sectional area of ​​the lubrication hole (1623a1). In other words, the cross-sectional area of ​​the lubrication groove (1623a2) may be formed larger than the cross-sectional area of ​​the second lubrication passage (1623b). Accordingly, the actual cross-sectional area of ​​the first lubrication passage (1623a) may be formed larger than the cross-sectional area of ​​the second lubrication passage (1623b). Through this, the total cross-sectional area of ​​the first lubrication passage (1623a) including the lubrication groove (1623a2) is further increased, thereby further enhancing the lubrication effect on the central thrust surface (162b) of the back pressure plate (162) that receives a relatively high compressive force. At the same time, reliability can be ensured by minimizing the increase in surface pressure on the thrust surface (162b) of the back pressure plate (162) as the lubrication grooves (1623a2) are spaced apart from each other along the circumferential direction.

[0169] In this case, the lubrication groove (1623a2) may be formed only in a portion of the first lubrication passage (1623a), or the lubrication groove (1623a2) may be formed in the entire first lubrication passage (1623a). In the former case, the actual total cross-sectional area of ​​the first lubrication passage (1623a) is further expanded, while the leakage of refrigerant and / or oil through the first lubrication passage (1623a) can be adequately suppressed. In the latter case, the actual total cross-sectional area of ​​the first lubrication passage (1623a) is further increased, thereby further enhancing the lubrication effect on the central thrust surface (162b) among the thrust surfaces (162b) of the back pressure plate (162).

[0170] Meanwhile, the lubrication groove (1623a2) may be formed in an annular shape so that the lubrication holes (1623a1) are connected collectively. For example, the lubrication groove (1623a2) may be formed as a single annular shape as shown in FIG. 10, but may be formed so that multiple lubrication holes (1623a1) are all accommodated in the single lubrication groove (1623a2). In this case, the lubrication holes (1623a1) forming part of the first lubrication passage (1623a) may be formed spaced apart by a predetermined interval along the circumferential direction. Accordingly, the actual total cross-sectional area of ​​the first lubrication passage (1623a) is further increased, thereby further enhancing the lubrication effect on the central thrust surface (162b) among the thrust surfaces (162b) of the back pressure plate (162).

[0171] Meanwhile, although the back pressure chamber assembly according to the aforementioned embodiments has been examined primarily in the context of its application to a low-pressure scroll compressor, as previously explained, the back pressure chamber assembly according to the aforementioned embodiments can be applied in the same way to a high-pressure scroll compressor. However, while the back pressure chamber prevents the refrigerant in the back pressure chamber from leaking into the low-pressure chamber forming the suction space in a low-pressure compressor, the back pressure chamber can suppress the refrigerant in the high-pressure section forming the discharge space from flowing into the back pressure chamber and causing the pressure in the back pressure chamber to rise excessively.

Claims

1. A casing in which the internal space is separated into a low-pressure section forming an intake space and a high-pressure section forming a discharge space; A main frame provided in the internal space of the above casing; A fixed scroll coupled to one side of the main frame; A pivot scroll provided between the main frame and the fixed scroll to form a compression chamber between the fixed scroll and the main frame; and It includes a back pressure plate that is received on one side of the main frame facing the aforementioned rotating scroll and presses the rotating scroll toward the fixed scroll. The above back pressure plate is, A scroll compressor having at least one lubrication passage formed that penetrates from a back pressure surface facing away from the aforementioned rotating scroll to a thrust surface facing the aforementioned rotating scroll.

2. In Paragraph 1, A plate receiving groove into which the back pressure plate is inserted is formed in the main frame above, and A back pressure groove forming a back pressure chamber is formed on at least one of the back pressure surface of the back pressure plate and one side of the plate receiving groove facing it. One end of the above-mentioned fuel passage is, A scroll compressor connected to the above back pressure groove.

3. In Paragraph 2, A first back pressure passage is formed by continuously penetrating the fixed scroll and the main frame, and The above back pressure groove is, A scroll compressor connected to the high-pressure portion of the casing through the first back pressure passage.

4. In Paragraph 2, In the above fixed scroll and the above main frame, a first back pressure passage and a second back pressure passage are formed separately from each other, and The above back pressure groove is, A scroll compressor comprising a first back pressure groove communicating with the high-pressure portion of the casing through the first back pressure passage, and a second back pressure groove separated from the first back pressure groove and communicating with the compression chamber through the second back pressure passage.

5. In Paragraph 4, The above-mentioned fuel passage is, A first supply passage communicating with the first back pressure groove; and It includes a second supply passage connected to the second back pressure groove, and The total cross-sectional area of ​​the above-mentioned Class 1 circulation passage is, A scroll compressor formed to be smaller than or equal to the total cross-sectional area of ​​the above-mentioned second-class circulation channel.

6. In Paragraph 5, The above-mentioned first-class circulation passage is, It is composed of a lubrication hole penetrating the back pressure plate and a lubrication groove formed on the thrust surface of the back pressure plate in communication with the lubrication hole. The cross-sectional area of ​​the above lubrication groove is, A scroll compressor formed with a cross-sectional area larger than the above-mentioned lubrication hole.

7. In Paragraph 6, The above-mentioned lubrication holes are formed in multiple numbers at predetermined intervals along the circumferential direction, and The above lubrication groove is, A scroll compressor in which the plurality of lubrication holes are formed to be individually connected to each other.

8. In Paragraph 7, The above-mentioned lubrication holes are formed in multiple numbers at predetermined intervals along the circumferential direction, and The above lubrication groove is, A scroll compressor formed to accommodate the above-mentioned plurality of lubrication holes collectively.

9. In Paragraph 5, The above-mentioned second-class circulation path is, A scroll compressor formed such that at least a portion is located on a different line radially from the first flow channel.

10. In Paragraph 2, The above back pressure plate, A scroll compressor in which a drainage passage is formed connecting the inner and outer surfaces of the back pressure plate.

11. In Paragraph 10, The above drainage passage is, A scroll compressor formed by a hole penetrating between the inner and outer surfaces of the back pressure plate, or by a recessed groove on the thrust surface of the back pressure plate facing the rotary scroll.

12. In Paragraph 2, A scroll compressor having a lubrication guide groove having a predetermined depth formed on the back surface of the rotary scroll facing the thrust surface of the back pressure plate.

13. In any one of paragraphs 1 through 12, The above-mentioned rotating scroll is, A pivot plate portion provided between the main frame and the fixed scroll and eccentrically coupled to a rotation axis; A pivot wrap extending from one side of the pivot plate portion and configured to engage with the fixed wrap of the fixed scroll to form a compression chamber; and It includes a rotational shaft insertion part that overlaps the rotational wrap and the rotational shaft in the radial direction at the center of the rotational plate part and extends in the axial direction of the rotational shaft, and A scroll compressor in which a portion of the pivoting wrap extends from the front end surface of the rotating shaft insertion part facing the fixed scroll.

14. In Paragraph 13, The above-mentioned pivot plate portion is provided with a pivoting step surface between the outer surface of the pivoting wrap and the inner surface of the pivoting wrap facing it, and the above-mentioned fixed wrap is provided with a fixed step surface corresponding to the pivoting step surface. At least a portion of the above-mentioned back pressure plate, A scroll compressor formed to overlap with a compression chamber located closer to the center than the aforementioned pivoting step surface when projected in the axial direction.

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