Scroll compressor

Abstract

To provide a scroll compressor capable of reducing a discharge pressure loss without increasing machining processes.SOLUTION: A discharge chamber 27 is composed of a first chamber 56 and a second chamber 57. The second chamber 57 is divided from the first chamber 56 by a partition wall 53 integrally formed with a rear casing 9 so that refrigerant discharged from a discharge hole of a fixed scroll into the first chamber 56 flows via an oil separator 52 into the second chamber 57, and via the second chamber 57 to a discharge port 51. A bypass channel 59 is constructed to communicate the first chamber 56 with the second chamber 57 without passing through the oil separator 52.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a scroll compressor in which a working fluid discharged from a fixed scroll to a discharge chamber passes through an oil separator and is then discharged from a discharge port. [Background technology]

[0002] Conventionally, this type of scroll compressor has been equipped with a compression mechanism consisting of a fixed scroll with a spiral wrap on the surface of its end plate and a movable scroll with a spiral wrap on the surface of its end plate, with the wraps of each scroll facing each other to form a compression chamber between the wraps, and the movable scroll revolving in an orbital motion relative to the fixed scroll to compress the working fluid (refrigerant) in the compression chamber.

[0003] The compressed working fluid is then discharged into a discharge chamber from the discharge hole of the fixed scroll, passes through an oil separator to be separated from the oil, and is then discharged from a discharge port (see, for example, Patent Document 1 and Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-20280 [Patent Document 2] Japanese Patent Application Publication No. 2023-160250 Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, the working fluid discharged from the fixed scroll into the discharge chamber passes through the oil separator before reaching the discharge port. This causes a pressure loss (discharge pressure loss) during the process of passing through the oil separator, resulting in a decrease in efficiency.

[0006] One method for reducing this discharge pressure loss is to enlarge the diameter of the discharge hole in the fixed scroll, but this method cannot be adopted because it increases discharge pulsation.Also, as in Patent Document 2, there is a method in which a small hole is drilled in the oil separation pipe of the oil separator attached to the rear casing, and the discharge port and the discharge chamber are directly connected, thereby creating a path for the working fluid to reach the discharge port from the discharge chamber without passing through the oil separator.However, when a separate oil separator is attached to the rear casing as in Patent Document 2, the number of parts increases, and when the oil separator is constructed integrally with the rear casing, there are issues such as an increase in the number of processing steps.

[0007] The present invention has been made to solve the above-mentioned conventional technical problems, and has an object to provide a scroll compressor that can reduce discharge pressure loss without increasing the number of processing steps. [Means for solving the problem]

[0008] The scroll compressor of the present invention is characterized in that a discharge chamber is formed between a fixed scroll and a rear casing, and working fluid discharged from a discharge hole of the fixed scroll into the discharge chamber passes through an oil separator and is discharged to the outside of the rear casing from a discharge port, the discharge chamber comprising a first chamber and a second chamber, the second chamber being separated from the first chamber by a partition wall formed integrally with the rear casing, the working fluid discharged from the discharge hole of the fixed scroll into the first chamber passes through the oil separator and flows into the second chamber, and then passes through the second chamber to the discharge port, and a bypass passage is formed which connects the first chamber and the second chamber without passing through the oil separator.

[0009] The scroll compressor of the invention of claim 2 is characterized in that in the above invention, a groove is formed in the partition wall, and this groove constitutes a bypass passage.

[0010] The scroll compressor of the invention of claim 3 is characterized in that, in the above invention, the end face of the partition is located in the same plane as the end face of the opening edge of the rear casing, and the groove is formed as a recess in the end face of the partition.

[0011] The scroll compressor of the invention of claim 4 is characterized in that in the invention of claim 1, a through hole is formed in the partition wall, and this through hole constitutes a bypass passage.

[0012] The scroll compressor of the invention of claim 5 is characterized in that, in the invention of claim 1, it further comprises a sealing gasket interposed at the joint between the rear casing and the fixed scroll, and this gasket has a partition wall seal portion that seals between the end face of the partition wall and the fixed scroll, and a groove is formed in part of this partition wall seal portion, and this groove forms a bypass passage.

[0013] The scroll compressor of the invention of claim 6 is characterized in that in each of the above inventions, the second chamber is defined above the discharge hole of the fixed scroll within the rear casing.

[0014] The scroll compressor of the invention of claim 7 is characterized in that in the above invention, the second chamber is formed in the rear casing in the circumferential direction.

[0015] The scroll compressor of the invention of claim 8 is characterized in that in the above invention, the second chamber is formed in an annular shape within the rear casing.

[0016] The scroll compressor of the invention of claim 9 is characterized in that, in the invention of claim 6, it further comprises a sealing gasket interposed at the joint between the rear casing and the fixed scroll, the gasket having a partition wall seal portion that seals between the end face of the partition wall and the fixed scroll, and the partition wall seal portion is configured with dimensions corresponding to an area that is at least circumferentially wider than the partition wall.

[0017] The scroll compressor of the invention of claim 10 is characterized in that in the inventions of claims 1 to 5, the oil separator has an inlet hole through which the working fluid flows and is configured in the wall of the rear casing opposite the discharge hole of the fixed scroll, and the inlet hole of the oil separator is formed to point in a direction away from the discharge hole of the fixed scroll. [Effects of the Invention]

[0018] According to the present invention, in a scroll compressor in which a discharge chamber is formed between a fixed scroll and a rear casing, and working fluid discharged from the discharge hole of the fixed scroll into the discharge chamber passes through an oil separator and is discharged outside the rear casing from a discharge port, the discharge chamber is formed from a first chamber and a second chamber, and this second chamber is separated from the first chamber by a partition wall formed integrally with the rear casing, and the working fluid discharged from the discharge hole of the fixed scroll into the first chamber passes through the oil separator and flows into the second chamber, and then passes through this second chamber to reach the discharge port.Therefore, even when the volute volume is expanded, discharge pulsation in the first chamber can be effectively suppressed by expanding the first chamber and reducing the second chamber.

[0019] Furthermore, a bypass passage is provided that connects the first chamber and the second chamber without passing through the oil separator, so that the bypass passage effectively reduces discharge pressure loss in the oil separator, thereby improving efficiency.

[0020] In this case, as in the invention of claim 2, if a groove is formed in the partition wall formed in the casing so that a bypass passage is formed between the fixed scroll and the groove is integrally formed in the partition wall by, for example, aluminum casting, it becomes possible to form the bypass passage without increasing the number of processing steps or parts, and to achieve a reduction in discharge pressure loss.

[0021] Furthermore, as in the invention of claim 3, if a groove is formed as a recess in the end face of the partition wall that is located on the same plane as the end face of the opening edge of the rear casing, the first chamber and the second chamber are separated by joining the fixed scroll to the rear casing, and at the same time a bypass passage can be formed within the groove, making it possible to extremely easily reduce discharge pressure loss.

[0022] Alternatively, as in the invention of claim 4, a through hole may be formed in the partition wall, and this through hole may serve as a bypass passage.

[0023] Furthermore, as in the invention of claim 5, when a sealing gasket is provided at the joint between the rear casing and the fixed scroll, and this gasket has a partition wall seal portion that seals between the end face of the partition wall and the fixed scroll, a groove may be formed in part of the partition wall seal portion, and this groove may form a bypass passage.

[0024] Furthermore, as in the invention of claim 6, by defining the second chamber above the discharge hole of the fixed scroll inside the rear casing, it is possible to easily form the oil separator.

[0025] Furthermore, if the second chamber is formed in the circumferential direction within the rear casing as in the invention of claim 7, or if the second chamber is formed in an annular shape within the rear casing as in the invention of claim 8, it becomes possible to form a passage with the discharge port very easily while maintaining the proper positioning of the oil separator.

[0026] Furthermore, as in claim 9, when a sealing gasket is provided at the joint between the rear casing and the fixed scroll, and this gasket has a partition wall seal portion that seals between the end face of the partition wall and the fixed scroll, by configuring this partition wall seal portion to have dimensions that correspond to an area at least wider in the circumferential direction than the partition wall, even if customer requirements for the position of the discharge port provided in the upper part of the rear casing change and the position of the partition wall of the rear casing is also changed, the partition wall seal portion, which is configured to have dimensions that correspond to an area at least wider in the circumferential direction than the partition wall, can smoothly seal between the end face of the partition wall and the fixed scroll. This makes it possible to standardize gaskets for scroll compressors of different designs, enabling the shape of the second chamber to be optimized for each customer, while reducing parts costs.

[0027] Furthermore, as in claim 10, by configuring the oil separator on the wall of the rear casing opposite the discharge hole of the fixed scroll and orienting the inlet hole through which the working fluid flows into the oil separator in a direction away from the discharge hole of the fixed scroll, it is possible to extend the distance from the discharge hole of the fixed scroll to the inlet hole of the oil separator. This makes it possible to configure a wide space in front of the inlet hole of the oil separator even when the volute volume is large, making it possible to effectively reduce discharge pulsation with the same package (dimensions). [Brief explanation of the drawings]

[0028] [Figure 1] 1 is a cross-sectional view of a scroll compressor according to an embodiment of the present invention. [Figure 2] 2 is a cross-sectional view of a rear casing and a fixed scroll of the scroll compressor of FIG. 1. [Figure 3] FIG. 2 is a side view of a rear casing of the scroll compressor of FIG. [Figure 4] FIG. 2 is a rear view of the rear casing of the scroll compressor of FIG. [Figure 5] FIG. 2 is a front view of a rear casing of the scroll compressor of FIG. [Figure 6] 6 is an enlarged perspective view of a groove formed in a partition seal portion of the rear casing of FIG. 5. FIG. [Figure 7] FIG. 4 is an enlarged cross-sectional view of the rear casing of the oil separator portion. [Figure 8] 10 is a diagram illustrating a case where an inlet hole of the oil separator faces a fixed scroll. FIG. [Figure 9] 2 is a diagram illustrating the effect of reducing discharge pressure loss in the scroll compressor of FIG. 1. FIG. [Figure 10] 2 is a diagram illustrating the effect of reducing discharge pulsation of the scroll compressor of FIG. 1. FIG. [Figure 11] FIG. 2 is a front view of a gasket of the scroll compressor of FIG. [Figure 12] 12 is a front view of the rear casing with the gasket of FIG. 11 attached and seen through the gasket. [Figure 13] FIG. 10 is a front view of a rear casing with a different design, seen through a gasket. DETAILED DESCRIPTION OF THE INVENTION

[0029] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Fig. 1 is a cross-sectional view of a scroll compressor 1 according to an embodiment of the present invention.

[0030] (1) Overall configuration of scroll compressor 1 The scroll compressor 1 of the embodiment is used, for example, in a refrigerant circuit of a vehicle air conditioner, and sucks in, compresses, and discharges a refrigerant as a working fluid for the vehicle air conditioner.It is a so-called inverter-integrated scroll compressor that includes an electric motor 2, an inverter 3 for operating the electric motor 2, and a compression mechanism 4 driven by the electric motor 2.

[0031] The scroll compressor 1 of the embodiment includes a main housing 6 that houses the electric motor 2 and the inverter 3 therein, a compression mechanism housing 7 that houses the compression mechanism 4 therein, an inverter cover 8, and a rear casing 9. The main housing 6, compression mechanism housing 7, inverter cover 8, and rear casing 9 are all made of metal (cast aluminum in the embodiment), and are joined together with bolts to form a housing 11 of the scroll compressor 1. In other words, the rear casing 9 forms a part of the housing 11.

[0032] 1, reference numeral 15 denotes a sealing gasket interposed at the joint between the compression mechanism housing 7 and a fixed scroll 21 (described later) and the rear casing 9. The configuration of this gasket 15 will be described in detail later.

[0033] The main housing 6 is composed of a cylindrical peripheral wall 6A and a partition wall 6B. This partition wall 6B is a partition that separates the inside of the main housing 6 into a motor accommodating section 12 that accommodates the electric motor 2 and an inverter accommodating section 13 that accommodates the inverter 3. One end face of the inverter accommodating section 13 is open, and this opening is closed by the inverter cover 8 after the inverter 3 is accommodated therein.

[0034] The motor accommodating section 12 also has an opening at the other end face, and after the electric motor 2 is accommodated, this opening is closed by the compression mechanism housing 7. In addition, a support section 16 for supporting one end of the rotating shaft 14 of the electric motor 2 (the end opposite to the compression mechanism 4) is protruded from the partition wall section 6B.

[0035] The compression mechanism housing 7 is open on the side opposite to the main housing 6, and after the compression mechanism 4 is housed in this opening, it is closed by the rear casing 9. The compression mechanism housing 7 is composed of a cylindrical peripheral wall portion 7A and a frame portion 7B on one end side (main housing 6 side) of the peripheral wall portion 7A, and the compression mechanism 4 is housed in the space defined by the peripheral wall portion 7A and the frame portion 7B. The frame portion 7B forms a partition wall that separates the inside of the main housing 6 from the inside of the compression mechanism housing 7.

[0036] In addition, a through hole 17 is provided in the frame portion 7B, through which the other end (the end on the compression mechanism 4 side) of the rotating shaft 14 of the electric motor 2 is inserted, and a front bearing 18 serving as a bearing member supporting the other end of the rotating shaft 14 is fitted into the through hole 17 on the compression mechanism 4 side.

[0037] The electric motor 2 is composed of a stator 25 around which a coil is wound, and a rotor 30. For example, direct current from a vehicle battery (not shown) is converted into three-phase alternating current by an inverter 3, and this is supplied to the coil of the electric motor 2, thereby driving the rotor 30 to rotate.

[0038] A suction port (not shown) is formed in the main housing 6, and refrigerant drawn in through the suction port passes through the main housing 6 and is then drawn into a suction section 37 outside the compression mechanism 4 in the compression mechanism housing 7. This cools the electric motor 2 with the drawn refrigerant. The refrigerant compressed in the compression mechanism 4 is discharged into a discharge chamber 27 as described below, and is then finally discharged out of the rear casing 9, i.e., into the refrigerant circuit, from a discharge port 51 (FIGS. 3 to 5) formed in the rear casing 9. The configuration of the rear casing 9 will be described in detail later.

[0039] The compression mechanism 4 is composed of a fixed scroll 21 and a movable scroll 22. The fixed scroll 21 integrally includes a disk-shaped end plate 23 and a spiral wrap 24 formed of an involute shape or a curve approximating an involute shape and standing on the surface (one side) of the end plate 23, and is fixed to the compression mechanism housing 7 with the surface of the end plate 23 on which the wrap 24 is standing facing the frame part 7B.

[0040] A discharge hole 26 is formed in the center of the end plate 23 of the fixed scroll 21, and this discharge hole 26 communicates with a discharge chamber 27 inside the rear casing 9. Reference numeral 28 denotes a discharge valve provided at the opening of the discharge hole 26 on the rear surface (other surface) side of the end plate 23. This discharge valve 28 opens when the pressure in a compression chamber 34 (described later) becomes higher than the pressure in the discharge chamber 27 and the differential pressure therebetween reaches a predetermined value, thereby connecting the discharge hole 26 and the discharge chamber 27.

[0041] The movable scroll 22 is a scroll that revolves around the fixed scroll 21, and is integrally provided with a disk-shaped end plate 31, a spiral wrap 32 that is involute-shaped or has a curve similar to an involute and is erected on the surface (one side) of the end plate 31, and a boss portion 33 that is formed and protrudes from the center of the back surface (the other side) of the end plate 31. The movable scroll 22 is disposed so that the wrap 32 faces the wrap 24 of the fixed scroll 21 with the protruding direction of the wrap 32 facing the fixed scroll 21, and the wraps 32 and 32 mesh with each other, forming the compression chamber 34 described above between each wrap 24 and 32.

[0042] That is, the wrap 32 of the movable scroll 22 faces the wrap 24 of the fixed scroll 21, and they are engaged with each other so that the tip of the wrap 32 contacts the surface of the end plate 23 and the tip of the wrap 24 contacts the surface of the end plate 31. A drive projection 48 that projects from a position eccentric from the axis of the rotary shaft 14 is provided on the other end of the rotary shaft 14, i.e., the end on the movable scroll 22 side. An eccentric bushing 36 is attached to this drive projection 48, and the drive projection 48 is provided on the other end of the rotary shaft 14 eccentrically from the axis of the rotary shaft 14.

[0043] In this case, the eccentric bushing 36 is attached to the drive projection 48 at a position eccentric from the axis of the eccentric bushing 36, and the eccentric bushing 36 is fitted into the boss portion 33 of the movable scroll 22. When the rotary shaft 14 is rotated together with the rotor 30 of the electric motor 2, the movable scroll 22 does not rotate on its own axis but makes an orbital motion relative to the fixed scroll 21. Reference numeral 49 denotes a balance weight attached to the outer peripheral surface of the rotary shaft 14 on the movable scroll 22 side of the front bearing 18.

[0044] Since the movable scroll 22 revolves eccentrically relative to the fixed scroll 21, the eccentric direction and contact position of each wrap 24, 32 move while rotating, and the compression chamber 34, which has drawn refrigerant from the aforementioned suction portion 37 on the outside, moves inward and gradually shrinks. As a result, the refrigerant is compressed and is finally discharged from the central discharge hole 26 through the discharge valve 28 into the discharge chamber 27.

[0045] 1, reference numeral 38 denotes an annular thrust plate. This thrust plate 38 serves to separate a back pressure chamber 39 formed on the back surface side of the end plate 31 of the movable scroll 22 from a suction section 37 serving as a suction pressure region outside the compression mechanism 4 within the compression mechanism housing 7. The thrust plate 38 is located outside the boss section 33 and interposed between the frame section 7B and the movable scroll 22.

[0046] As will be described later, oil at a reduced and adjusted discharge pressure is supplied to the back pressure chamber 39 via a back pressure passage 43 (FIG. 5) from an oil separator 52 (FIGS. 2, 4, and 5) formed integrally with the rear casing 9. The pressure (back pressure) within this back pressure chamber 39 generates a back pressure load that presses the movable scroll 22 against the fixed scroll 21. This back pressure load presses the movable scroll 22 against the fixed scroll 21 against the compression reaction force from the compression chamber 34 of the compression mechanism 4, maintaining contact between the wraps 24, 32 and the end plates 31, 23, and enabling the refrigerant to be compressed in the compression chamber 34.

[0047] (2) Structure of rear casing 9 Next, the structure of the rear casing 9 of the embodiment will be described with reference to Figures 2 to 10. The rear casing 9 is in the shape of a container with one side open, as shown in Figures 3 to 5. As described above, the fixed scroll 21 is joined to the rear casing 9 via the gasket 15, thereby closing the opening of the rear casing 9, and the entire space between the rear casing 9 and the fixed scroll 21 becomes the discharge chamber 27 described above.

[0048] (2-1) Partition wall 53 and bypass passage 59 The discharge port 51 described above is provided in the upper part of the rear casing 9. In this embodiment, as shown in Fig. 5, when the opening on one side of the rear casing 9 is viewed from the front, the discharge port 51 is provided in a position offset to the upper right, that is, in a position offset to one side (right) when viewed from the discharge hole 26 in the center of the fixed scroll 21. A partition wall 53 is formed integrally with the rear casing 9 near the discharge port 51 by casting aluminum, and this partition wall 53 divides the discharge chamber 27 into a first chamber 56 and a second chamber 57.

[0049] In this case, partition wall 53 is configured at an upper portion on the discharge port 51 side within discharge chamber 27, and has an arc-shaped portion 53A centered on or near discharge hole 26 of fixed scroll 21. The volume of first chamber 56 defined by such partition wall 53 is large, and discharge hole 26 of fixed scroll 21 described above is located within first chamber 56. Second chamber 57 is located adjacent to discharge port 51 and above discharge hole 26, and is configured as a small room above first chamber 56.

[0050] Furthermore, in this embodiment, the second chamber 57 is formed in the circumferential direction within the rear casing 9. The second chamber 57 may also be formed in the rear casing 9 in an annular shape.

[0051] In this case, the end face of partition wall 53 is located on the same plane as the end face of the opening edge of rear casing 9, and in this embodiment, partition wall 53 has groove 58 formed as an integral recess across the width direction of partition wall 53, as shown in Figure 6. Then, by joining rear casing 9 and fixed scroll 21, a bypass passage 59 is formed inside groove 58 between fixed scroll 21 and groove 58, and this bypass passage 59 communicates between first chamber 56 and second chamber 57 without passing through oil separator 52.

[0052] Since the gasket 15 described above is interposed on the rear casing 9 side of the fixed scroll 21, the bypass passage 59 is actually formed between the groove 58 and a partition wall seal portion 66 (described later) of the gasket 15. In other words, the bypass passage 59 is formed between the groove 58 and the fixed scroll 21 with the gasket 15 interposed therebetween.

[0053] In the above embodiment, the groove 58 is formed in the partition wall 53 and the bypass passage 59 is formed therein, but this is not limiting, and a through hole may be formed in the partition wall 53 and the bypass passage 59 may be formed inside this through hole. Alternatively, a groove may be formed in part of the partition wall seal portion 66 of the gasket 15 and the bypass passage 59 may be formed inside this groove.

[0054] (2-2) Inlet hole 61 of oil separator 52 The oil separator 52 described above is disposed vertically within the first chamber 56, and is integrally formed by casting aluminum on the rear wall 9A of the rear casing 9, which faces the discharge hole 26. In this case, the oil separator 52 is positioned offset to one side (the right side in FIG. 5) when viewed from the discharge hole 26 in the center of the fixed scroll 21, and the inner surface 52A is tubular with a circular cross section, with its upper portion communicating with the second chamber 57 and its lower portion communicating with the back pressure passage 43 described above (FIG. 7).

[0055] Furthermore, a plurality of inlet holes 61 (three in this embodiment) are formed in a vertically aligned row in the side wall of the oil separator 52, and open into the first chamber 56. In this case, the inlet holes 61 are formed so as to be oriented in a tangential direction (indicated by a dashed line in FIG. 7) that contacts the inner surface 52A of the oil separator 52. When the rear casing 9 and the fixed scroll 21 are joined, the inlet holes 61 of the oil separator 52 are adjacent to the discharge hole 26 of the fixed scroll 21 (FIG. 7). However, each inlet hole 61 is formed so as to be oriented obliquely in a direction away from the discharge hole 26 of the fixed scroll 21, i.e., in a direction in which the oil separator 52 is displaced (to the right in FIG. 5). As a result, the distance between the inlet holes 61 and the discharge hole 26 is longer than when the inlet holes 61 are configured so as to face the fixed scroll 21, as shown in FIG. 8.

[0056] The refrigerant (working fluid) containing oil that is discharged from the discharge hole 26 of the fixed scroll 21 to the first chamber 56 flows into the oil separator 52 from each inlet hole 61. The refrigerant that has flowed into the oil separator 52 swirls inside and moves upward, and then flows into the second chamber 57. The refrigerant that has flowed into the second chamber 57 passes through there and reaches the discharge port 51, and is then discharged to the outside.

[0057] Meanwhile, in the oil separator 52, oil is separated by centrifugal force as the refrigerant swirls. The separated oil flows downward and is supplied to the back pressure chamber 39 via the back pressure passage 43. Note that a portion of the refrigerant discharged from the discharge hole 26 of the fixed scroll 21 to the first chamber 56 flows into the second chamber 57 via the bypass passage 59 and reaches the discharge port 51 without passing through the oil separator 52 as described above.

[0058] In this way, the discharge chamber 27 is composed of the first chamber 56 and the second chamber 57, and the second chamber 57 is separated from the first chamber 56 by a partition wall 57 formed integrally with the rear casing 9. The refrigerant discharged from the discharge hole 26 of the fixed scroll 21 to the first chamber 56 flows into the second chamber 57 through the oil separator 52, and then passes through the second chamber 57 to reach the discharge port 51. Therefore, even when the volute volume of the compression mechanism 4 is expanded, the first chamber 56 can be expanded and the second chamber 57 can be reduced, thereby effectively suppressing discharge pulsation in the first chamber 56.

[0059] In addition, in the embodiment, a groove 58 is formed in the partition wall 57, and this groove 58 constitutes a bypass passage 59 between the fixed scroll 21 and the partition wall 57, which connects the first chamber 56 and the second chamber 57 without passing through the oil separator 52. Therefore, the bypass passage 59 effectively reduces the discharge pressure loss in the oil separator 52, thereby improving efficiency.

[0060] In this case, partition wall 57 separating first chamber 56 and second chamber 57 is formed integrally with rear casing 9, and groove 58 is formed integrally with partition wall 57 to define bypass passage 59 between partition wall 57 and fixed scroll 21. Therefore, by integrally forming groove 58 with partition wall 57 by aluminum casting as in the embodiment, bypass passage 59 can be formed without increasing the number of processing steps or parts, and discharge pressure loss can be reduced.

[0061] In addition, in the embodiment, the rear casing 9, which has a container-like shape with one side open, is joined to the fixed scroll 21, thereby blocking the opening of the rear casing 9 and making the entire space between the rear casing 9 and the fixed scroll 21 into the discharge chamber 27. Therefore, even if there are restrictions on the packaging (dimensions) of the scroll compressor 1, the discharge chamber 27 consisting of the first chamber 56 and the second chamber 57 can be made large, thereby effectively reducing discharge pulsation.

[0062] Furthermore, in the embodiment, a groove 58 is formed as a recess in the end face of the partition wall 57, which is located on the same plane as the end face of the opening edge of the rear casing 9. Therefore, by joining the fixed scroll 21 to the rear casing 9, the first chamber 56 and the second chamber 57 are separated, and at the same time, a bypass passage 59 can be formed within the groove 58, making it possible to reduce discharge pressure loss extremely easily.

[0063] In addition, in this embodiment, the second chamber 57 is defined above the discharge hole 26 of the fixed scroll 21 inside the rear casing 9, so that the oil separator 52 can be easily formed.

[0064] Furthermore, in this embodiment, the second chamber 57 is formed in the circumferential direction within the rear casing 9, so that it is possible to very easily form a passage with the discharge port 51 while maintaining the proper positioning of the oil separator 52.

[0065] In addition, the oil separator 52 has an inlet hole 61 through which the refrigerant flows, and is configured in the back wall 9A of the rear casing 9 opposite the discharge hole 26 of the fixed scroll 21, so that oil is centrifuged from the refrigerant that flows in through the inlet hole 61.The inlet hole 61 is also formed to point in a direction away from the discharge hole 26 of the fixed scroll 21, so that the distance from the discharge hole 26 of the fixed scroll 21 to the inlet hole 61 of the oil separator 52 is extended.

[0066] This allows a larger space to be created in front of the inlet hole 61 of the oil separator 52 compared to when the inlet hole 61 is opposite the fixed scroll 21 as shown in Figure 8. Therefore, even if the oil separator 52 must be located close to the discharge hole 26 of the fixed scroll 21 in order to configure the scroll compressor 1 in the same package (dimensions) despite the increased volute volume of the compression mechanism 4, it becomes possible to effectively reduce discharge pulsation in the space in front of the inlet hole 61 of the oil separator 52.

[0067] In this case, when the oil separator 52 is provided in the first chamber 56 of the discharge chamber 27 at a position offset vertically on the rear wall 9A of the rear casing 9 and to one side as viewed from the discharge hole 26 as in the embodiment, by forming the inlet hole 61 of the oil separator 52 to face in the direction in which the oil separator 52 is offset, the distance from the discharge hole 26 to the inlet hole 61 can be easily extended, and the space in front of the inlet hole 61 can be smoothly expanded.

[0068] Figure 9 shows the effect of reducing discharge pressure loss with the above configuration. (A) in this figure shows the case of a conventional scroll compressor, and (B) shows the case of the scroll compressor 1 with the above configuration. With the conventional case taken as 100%, the above configuration was able to reduce discharge pressure loss to 53%.

[0069] 10 shows the effect of reducing discharge pulsation with the above configuration. (C) in this figure shows the case of a conventional scroll compressor, and (D) shows the case of the scroll compressor 1 with the above configuration. With the conventional case taken as 100%, the above configuration was able to reduce discharge pulsation to 88%.

[0070] (3) Shape of gasket 15 11 to 13, the configuration of the gasket 15 interposed at the joint between the compression mechanism housing 7 and the fixed scroll 21 and the rear casing 9 will be described. The gasket 15 of the embodiment is made of a metal plate material, and as shown in Fig. 11, has an annular shape that matches the shape of the joint surfaces between the compression mechanism housing 7 and the fixed scroll 21 and the rear casing 9. Note that 62 is a bolt hole that matches the bolt hole 63 (Fig. 5) of the rear casing 9, and 64 is a passage hole that matches the back pressure passage 43.

[0071] Additionally, the upper portion of gasket 15 is widened, and this widened portion serves as a partition wall seal portion 66 that seals between the end face of partition wall 53 of rear casing 9 and fixed scroll 21. Therefore, the aforementioned bypass passage 59 is formed between groove 58 of partition wall 53 of rear casing 9 and partition wall seal portion 66 of gasket 15 (this means between groove 58 and fixed scroll 21).

[0072] The inner edge of the partition wall seal portion 66, i.e., the inner edge of the gasket 15, is located on the outer edge of the end face of the partition wall 53 and has an arc shape that follows the arc-shaped portion 53A of the partition wall 53. Figure 12 shows a front view of the rear casing 9 in Figure 5 with this gasket 15 attached and viewed through the gasket 15. As shown in Figure 12, the partition wall seal portion 66 of the gasket 15 is configured with dimensions that correspond to a wider area in the circumferential direction of the rear casing 9 than the partition wall 53, and in the embodiment, is configured with dimensions that correspond to an area spanning 180° in the circumferential direction of the rear casing 9.

[0073] 13 shows a perspective view of the rear casing 9 with the gasket 15 attached when, at the request of a customer, the position of the discharge port 51 is shifted to the other side (left) as viewed from the discharge hole 26 at the center of the fixed scroll 21. In this case, the partition wall 53 is configured to extend from one side to the other side of the upper part of the rear casing 9, and the volume of the second chamber 57 is also larger than in the case of FIG. 12 (FIG. 5).

[0074] However, as described above, by configuring the partition wall seal portion 66 of the gasket 15 with a dimension (180°) that corresponds to a wider circumferential area of ​​the rear casing 9 than the partition wall 53 in the case of Figure 12 (Figure 5), the partition wall 53 in the case of Figure 13 can also be sealed without any problems by the partition wall seal portion 66.

[0075] In this way, gasket 15, which is interposed at the joint between rear casing 9 and fixed scroll 21, is provided with a partition wall seal portion 66 that seals between the end face of partition wall 53 and fixed scroll 21, and this partition wall seal portion 66 is configured with dimensions that correspond to an area that is at least wider circumferentially than partition wall 53.By configuring this partition wall seal portion 66 with dimensions that correspond to an area that is at least wider circumferentially than partition wall 53 for each customer, even if the requirements for the position of discharge port 51 provided at the top of rear casing 9 change and the position of partition wall 53 of rear casing 9 is also changed (Figure 13), it is possible to smoothly seal between the end face of partition wall 53 and fixed scroll 21 by partition wall seal portion 66, which is configured with dimensions that correspond to an area that is at least wider circumferentially than partition wall 53.

[0076] This makes it possible to standardize the gasket 15 for scroll compressors 1 of different designs, thereby enabling the shape of the second chamber 57 to be optimized for each customer while reducing parts costs.

[0077] In this case, by configuring the partition seal portion 66 to have dimensions corresponding to an area spanning 180° in the circumferential direction of the rear casing 9 as in this embodiment, it is possible to reliably accommodate changes in the position of the partition 53.

[0078] Furthermore, in the embodiment, the inner edge of gasket 15 has an arc shape that follows arc-shaped portion 53A of partition wall 53. Therefore, even if the dimensions or position of second chamber 57 change depending on the position of discharge port 51, by keeping the arc diameter of arc-shaped portion 53A of partition wall 53 the same between the cases of FIGS. 12 and 13 , the inner edge of gasket 15 can smoothly seal between partition wall 53 and fixed scroll 21.

[0079] In the embodiment, the second chamber 57 is configured as a small room above the first chamber 56, but if the second chamber 57 is formed in a circular ring shape within the rear casing 9 as described above, the second chamber 57 will be defined by a 360° area around the first chamber 56 (also in this case, at least a portion of the second chamber 57 will be located above the first chamber 56).

[0080] In this case, since partition wall 53 is formed in an annular shape, partition wall seal portion 66 of gasket 15 is also configured in an annular shape (a 360° area). With this configuration, even if a customer requests a design in which second chamber 57 is formed in an annular shape, partition wall seal portion 66 of gasket 15 can smoothly seal between the end face of partition wall 53 and fixed scroll 21.

[0081] In the above embodiments, the present invention is applied to a scroll compressor used in a refrigerant circuit of a vehicle air conditioner, but is not limited to this and is effective for scroll compressors used in refrigerant circuits of various refrigeration devices. In addition, in the above embodiments, the present invention is applied to a so-called inverter-integrated scroll compressor, but is not limited to this and is also applicable to a normal scroll compressor that does not have an integrated inverter.

[0082] Furthermore, the specific structure and shape, such as the position of the discharge port 51, shown in the embodiment are not limited to those shown, and it goes without saying that various modifications are possible within the scope of the invention. [Explanation of symbols]

[0083] 1 Scroll compressor 4. Compression mechanism 6 Main Housing 7 Compression mechanism housing 9 Rear casing 9A Back wall (wall) 11. Housing 15 Gasket 21 Fixed Scroll 22 movable scroll 23, 31 Head plate 24, 32 laps 26 Discharge hole 27 Discharge chamber 28 Discharge valve 34 Compression chamber 51 Discharge port 52 Oil separator 53 Bulkhead 53A Arc-shaped section 56 First Chamber 57 Second Chamber 58 Groove 59 Bypass Passage 61 Entrance hole 66 Bulkhead seal

Claims

1. A scroll compressor in which a discharge chamber is formed between a fixed scroll and a rear casing, and working fluid discharged from a discharge hole of the fixed scroll into the discharge chamber passes through an oil separator and is discharged to the outside of the rear casing from a discharge port, the discharge chamber is composed of a first chamber and a second chamber, and the second chamber is separated from the first chamber by a partition wall formed integrally with the rear casing, The working fluid discharged from the discharge hole of the fixed scroll into the first chamber passes through the oil separator, flows into the second chamber, and reaches the discharge port through the second chamber, a bypass passage that communicates the first chamber with the second chamber without passing through the oil separator;

2. 2. The scroll compressor according to claim 1, wherein a groove is formed in the partition wall, and the groove constitutes the bypass passage.

3. 3. The scroll compressor according to claim 2, wherein an end surface of the partition wall is located on the same plane as an end surface of an opening edge of the rear casing, and the groove is formed as a recess in the end surface of the partition wall.

4. 2. The scroll compressor according to claim 1, wherein a through hole is formed in the partition wall, and the through hole constitutes the bypass passage.

5. a sealing gasket disposed at a joint between the rear casing and the fixed scroll; 2. The scroll compressor according to claim 1, wherein the gasket has a partition wall seal portion that seals between the end face of the partition wall and the fixed scroll, and a groove is formed in a part of the partition wall seal portion, and the groove constitutes the bypass passage.

6. 6. The scroll compressor according to claim 1, wherein the second chamber is defined in the rear casing above a discharge hole of the fixed scroll.

7. 7. The scroll compressor according to claim 6, wherein the second chamber is formed in the rear casing in a circumferential direction.

8. 8. The scroll compressor according to claim 7, wherein the second chamber is formed in an annular shape within the rear casing.

9. a sealing gasket disposed at a joint between the rear casing and the fixed scroll; 7. The scroll compressor according to claim 6, wherein the gasket has a partition wall seal portion that seals between the end face of the partition wall and the fixed scroll, and the partition wall seal portion is configured with dimensions corresponding to an area that is wider than the partition wall in at least the circumferential direction.

10. the oil separator has an inlet hole through which the working fluid flows, and is configured in a wall of the rear casing opposite to a discharge hole of the fixed scroll, 6. The scroll compressor according to claim 1, wherein the inlet hole of the oil separator is formed so as to be directed in a direction away from the discharge hole of the fixed scroll.

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