Compressors and refrigeration equipment.

Abstract

Invention details;

Description

Compressors and refrigeration equipment

[0001] The present disclosure relates to a compressor and a refrigeration device.

[0002] Patent Document 1 discloses a scroll compressor including a casing, a compression mechanism, and a housing that supports a crankshaft (drive shaft) connected to the compression mechanism. The compression mechanism has a fixed scroll and a movable scroll (orbiting scroll) that meshes with the fixed scroll. The housing has a pressure-contact portion that is pressure-contacted to the casing and an opposing portion that is spaced from the pressure-contact portion and faces the casing with a gap between them. In the scroll compressor of Patent Document 1, the opposing portion of the housing and the casing are welded.

[0003] Japanese Patent Application Laid-Open No. 2017-25762

[0004] In the scroll compressor of Patent Document 1, the movable scroll is connected to the crankshaft and is sandwiched between the fixed scroll and the housing. Therefore, vibrations generated in the compression mechanism during operation of the scroll compressor are transmitted to the casing via the crankshaft and the housing. When the vibrations are transmitted to the casing, there is a problem in that the radiated sound (noise) generated from the scroll compressor increases.

[0005] An object of the present disclosure is to reduce compressor noise.

[0006] The first aspect relates to a compressor (10). The compressor (10) includes a casing (20) having a cylindrical body (20a), a fixed member (F) housed in the casing (20) and fixed to the body (20a), and a plurality of welds (80) provided in the circumferential direction of the body (20a), the plurality of welds (80) connecting the body (20a) to the fixed member (F). The fixed member (F) is a compression mechanism (40) that compresses a refrigerant, or a support member (B) that rotatably supports a drive shaft (11) connected to the compression mechanism (40). The inner diameter of the body portion (20a) and the outer diameter of the member to be fixed (F) in the rated operating state of the compressor (10) have a fitting relationship that corresponds to a combination of the tolerance class of the hole and the tolerance class of the shaft (hole / shaft) defined in ISO 286 of H8 / f7, F8 / h9, H7 / f7, F8 / h6, H7 / g6, or G7 / h6.

[0007] In the first aspect, the body portion (20a) of the casing (20) and the fixed member (F) are fixed by a weld. During rated operation of the compressor (10), the body portion (20a) expands as the refrigerant pressure in the casing (20) increases, and the inner diameter of the body portion (20a) and the outer diameter of the fixed member (F) achieve the fit defined by ISO 286. This fit creates a local gap between the body portion (20a) and the fixed member (F). This allows the fixed member (F) to move slightly relative to the casing (20). This converts vibration energy transmitted from the compression mechanism (40) to the fixed member (F) during operation of the compressor (10) into kinetic energy due to the movement of the fixed member (F) or thermal energy due to friction between the fixed member (F) and the casing (20), thereby damping the vibration transmitted from the compression mechanism (40). As a result, the noise generated by the compressor (10) can be reduced.

[0008] In the second aspect, in the first aspect, the inner diameter of the body portion (20a) and the outer diameter of the fixed member (F) in the assembled state of the compressor (10) have a fitting relationship in which the combinations of the hole tolerance class and the shaft tolerance class (hole / shaft) defined in ISO 286 correspond to H7 / n6, 7 / r6, 7 / s6, and 8 / u8.

[0009] In the second mode, when the compressor (10) is assembled, the inner diameter of the body portion (20a) and the outer diameter of the member to be fixed (F) are in the above-mentioned fitting relationship defined by ISO 286, so that the member to be fixed (F) is fixed to the body portion (20a) by the welded portion (80) and the fitting.

[0010] In a third aspect, in the first or second aspect, a main bearing housing (50) is provided as the support member (B) that supports the compression mechanism (40). The compression mechanism (40) has a fixed scroll (60) and an orbiting scroll (70) that meshes with the fixed scroll (60). The fixed target member (F) is the main bearing housing (50).

[0011] In a third aspect, the fixed object (F) is the main bearing housing (50) of the scroll compressor (10). The main bearing housing (50) supports the compression mechanism (40), and therefore vibrations of the compression mechanism (40) are easily transmitted to the main bearing housing (50). By applying the above-described fitting relationship defined in ISO 286 between the inner diameter of the body portion (20a) and the outer diameter of the main bearing housing (50), the noise of the compressor can be further reduced.

[0012] In a fourth aspect, in any one of the first to third aspects, the body portion (20a) and the fixing target member (F) are welded to each other at the welded portion (80) via a pin (81).

[0013] A fifth aspect is a refrigeration system including the compressor (10) of any one of the first to fourth aspects and a refrigerant circuit (1a) through which refrigerant compressed by the compressor (10) flows.

[0014] In the fifth aspect, it is possible to provide a refrigeration system (1) in which the noise of the compressor (10) is reduced.

[0015] FIG. 1 is a refrigerant circuit diagram showing the configuration of a refrigeration system of this embodiment. FIG. 2 is a longitudinal cross-sectional view showing the configuration of a scroll compressor. FIG. 3 is a cross-sectional view taken along line III-III in FIG. 2. FIG. 4 is an enlarged view of the contact area and its surroundings in the assembled state of the scroll compressor. FIG. 5 is a view corresponding to FIG. 3 showing the scroll compressor in its rated operating state. FIG. 6 is a table showing terms indicating fitting relationships, tolerance classes specified in ISO 286 corresponding to the fitting relationships, and dimensional tolerance ranges for a reference dimension of φ145 mm corresponding to the tolerance classes. FIG. 7 is a transverse cross-sectional view showing a sub-bearing of Modified Example 1.

[0016] Embodiments Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. Note that the present disclosure is not limited to the embodiments shown below, and various modifications are possible within the scope of the technical concept of the present disclosure. Since the drawings are intended to conceptually explain the present disclosure, dimensions, ratios, or numbers may be exaggerated or simplified as necessary to facilitate understanding.

[0017] (1) Overview of Refrigeration Device As shown in FIG. 1, a compressor (10) is provided in a refrigeration device (1). The refrigeration device (1) has a refrigerant circuit (1a) filled with a refrigerant. The refrigerant circuit (1a) has a compressor (10), a radiator (3), a pressure reduction mechanism (4), and an evaporator (5). The pressure reduction mechanism (4) is, for example, an expansion valve. The refrigerant circuit (1a) performs a vapor compression refrigeration cycle.

[0018] The refrigeration system (1) is an air conditioning system. The air conditioning system may be a cooling-only system, a heating-only system, or an air conditioning system that switches between cooling and heating. In this case, the air conditioning system has a switching mechanism (e.g., a four-way switching valve) that switches the refrigerant circulation direction. The refrigeration system (1) may be a water heater, a chiller unit, a cooling system that cools the air inside a storage unit, or the like. The cooling system cools the air inside a refrigerator, a freezer, a container, or the like.

[0019] (2) Compressor The compressor (10) of this embodiment is a scroll compressor. As shown in Fig. 2, the scroll compressor (10) includes a casing (20), an electric motor (30), a drive shaft (11), and a compression mechanism (40). The casing (20) accommodates the electric motor (30), the drive shaft (11), and the compression mechanism (40).

[0020] In the following description, the term "axial direction" refers to the direction in which the drive shaft (11) extends, the term "radial direction" refers to the direction perpendicular to the axis of the drive shaft (11), and the term "circumferential direction" refers to the circumferential direction based on the axis of the drive shaft (11). The term "radially inner" refers to the side closer to the axis of the drive shaft (11), and the term "radially outer" refers to the side farther from the axis of the drive shaft (11).

[0021] (2-1) Casing The casing (20) is a vertically long sealed container. The casing (20) has a cylindrical body (20a) extending in the vertical direction and two lids (20b) closing both ends of the body (20a). When viewed in the axial direction, the body (20a) has a non-circular shape.

[0022] An oil reservoir (21) is provided at the bottom of the casing (20). Lubricating oil is stored in the oil reservoir (21). A suction pipe (12) is connected to the top of the casing (20). A discharge pipe (13) is connected to the body (20a) of the casing (20).

[0023] (2-2) Electric Motor The electric motor (30) has a stator (31) and a rotor (32). The stator (31) is fixed to the inner circumferential surface of the casing (20). The rotor (32) is disposed inside the stator (31). The drive shaft (11) passes through the rotor (32). The rotor (32) is fixed to the drive shaft (11).

[0024] (2-3) Drive Shaft The drive shaft (11) extends in the vertical direction along the central axis of the casing (20) and has a main shaft portion (14) and an eccentric portion (15).

[0025] The eccentric portion (15) is provided at the upper end of the main shaft portion (14). The outer diameter of the eccentric portion (15) is smaller than the outer diameter of the main shaft portion (14). The axis of the eccentric portion (15) is eccentric by a predetermined distance with respect to the axis of the main shaft portion (14).

[0026] An upper portion of the main shaft portion (14) passes through a housing (50) described below and is rotatably supported by an upper bearing (51) of the housing (50). A lower portion of the main shaft portion (14) is rotatably supported by an auxiliary bearing (22) described below.

[0027] (2-4) Housing The casing (20) accommodates a housing (50). The housing (50) is a main bearing support member that rotatably supports the drive shaft (11). The housing (50) corresponds to the support member (B) of the present disclosure and also corresponds to the main bearing housing of the present disclosure.

[0028] The housing (50) is disposed below the compression mechanism (40). The housing (50) supports the compression mechanism (40). The housing (50) is disposed above the electric motor (30). The inlet end of the discharge pipe (13) is disposed between the housing (50) and the electric motor (30).

[0029] The housing (50) is formed in a cylindrical shape extending in the axial direction (vertical direction). The outer diameter of the upper portion of the housing (50) is larger than the outer diameter of the lower portion of the housing (50). The inner diameter of the upper portion of the housing (50) is larger than the inner diameter of the lower portion of the housing (50).

[0030] The housing (50) has an annular portion (52), a recess (53), and an upper bearing (51). The annular portion (52) is provided on the outer periphery of the housing (50). The annular portion (52) has a non-circular shape when viewed in the axial direction. The recess (53) is formed in the upper central portion of the housing (50). The center of the recess (53) is formed in a dish shape that is recessed downward. The recess (53) forms a crank chamber (54) that accommodates a boss portion (73) of the orbiting scroll (70), which will be described later.

[0031] The eccentric portion (15) rotates eccentrically in the crank chamber (54). The upper bearing (51) is formed on the lower side of the housing (50). Specifically, the upper bearing (51) is formed below the recess (53). A bearing metal (51a) is fitted to the inner periphery of the upper bearing (51). The upper bearing (51) rotatably supports the main shaft portion (14) of the drive shaft (11) via the bearing metal (51a).

[0032] As shown in Fig. 3, a notch (55) is formed in the outer peripheral surface of the annular portion (52). The notch (55) passes through the annular portion (52) in the up-down direction. The notch (55) is recessed radially inward. A discharge passage (56) through which gas refrigerant discharged from the compression mechanism (40) passes is formed between the notch (55) and the inner peripheral surface of the casing (20).

[0033] The housing (50) is fixed inside the casing (20). Specifically, the outer peripheral surface of the annular portion (52) of the housing (50) is fixed to the inner peripheral surface of the body portion (20a) of the casing (20). The fixing structure of the housing (50) will be described later.

[0034] (2-5) Compression Mechanism The compression mechanism (40) includes a fixed scroll (60) and an orbiting scroll (70). The fixed scroll (60) is fixed to the upper surface of the housing (50). The orbiting scroll (70) is disposed between the fixed scroll (60) and the housing (50).

[0035] (2-5-1) Fixed Scroll The fixed scroll (60) has a fixed end plate (61), a fixed wrap (62), and an outer peripheral wall (63). The fixed end plate (61) is formed in a disk shape.

[0036] The fixed side wrap (62) is formed in a spiral shape. The fixed side wrap (62) protrudes downward from the front surface (the lower surface in FIG. 2 ) of the fixed side head plate (61). The fixed side wrap (62) is arranged inside the outer peripheral wall (63) of the fixed side head plate (61).

[0037] The outer peripheral wall (63) is formed in a substantially cylindrical shape. The outer peripheral wall (63) protrudes downward from the outer edge of the front surface (the lower surface in FIG. 2 ) of the fixed-side end plate (61). The outer peripheral wall (63) is provided so as to surround the outer periphery of the fixed-side wrap (62). The tip end surface (the lower surface in FIG. 2 ) of the fixed-side wrap (62) and the tip end surface (the lower surface in FIG. 2 ) of the outer peripheral wall (63) are located at approximately the same height.

[0038] The fixed side end plate (61) is located on the outer periphery side and is formed continuously with the fixed side wrap (62). The tip end surface of the fixed side wrap (62) and the tip end surface of the outer periphery wall (63) are formed to be substantially flush with each other. The fixed scroll (60) is fixed to the housing (50).

[0039] (2-5-2) Orbiting Scroll The orbiting scroll (70) has an orbiting-side end plate (71), an orbiting-side wrap (72), and a boss portion (73). The orbiting-side end plate (71) is formed in a disk shape. The orbiting-side wrap (72) is formed in a spiral shape. The orbiting-side wrap (72) protrudes upward from the front surface (upper surface in FIG. 2 ) of the orbiting-side end plate (71). The orbiting-side wrap (72) meshes with the fixed-side wrap (62).

[0040] The boss portion (73) is formed at the center of the back surface (the lower surface in FIG. 2 ) of the orbiting-side end plate (71). The eccentric portion (15) of the drive shaft (11) is inserted into the boss portion (73). This connects the drive shaft (11) to the orbiting scroll (70). In other words, the drive shaft (11) is connected to the compression mechanism (40).

[0041] (2-5-3) Suction Port, Discharge Port A suction port (64) is formed in the outer peripheral wall (63) of the fixed scroll (60). The suction port (64) opens near the end of the fixed side wrap (62). The downstream end of the suction pipe (12) is connected to the suction port (64).

[0042] A discharge port (65) is formed in the center of the fixed end plate (61) of the fixed scroll (60). The discharge port (65) opens in the upper surface of the fixed end plate (61) of the fixed scroll (60). High-pressure gas refrigerant discharged from the discharge port (65) flows into the lower space (24) of the housing (50) through a discharge passage (56) formed in the housing (50).

[0043] (2-5-4) Fluid Chamber The compression mechanism (40) has a fluid chamber (S) into which the refrigerant flows. The fluid chamber (S) is formed between the fixed scroll (60) and the orbiting scroll (70). The orbiting-side wrap (72) of the orbiting scroll (70) is disposed so as to mesh with the fixed-side wrap (62) of the fixed scroll (60). The meshing of the fixed-side wrap (62) and the orbiting-side wrap (72) compresses the gas refrigerant in the fluid chamber (S).

[0044] (2-6) Oldham Coupling An Oldham coupling (45) is provided at the top of the housing (50). The Oldham coupling (45) is disposed between the housing (50) and the orbiting scroll (70). The Oldham coupling (45) prevents the orbiting scroll (70) from rotating on its axis.

[0045] (2-7) Auxiliary Bearing The auxiliary bearing (22) is an auxiliary bearing support member that rotatably supports the drive shaft (11). The auxiliary bearing (22) supports the end of the drive shaft (11) opposite the compression mechanism (40) (the lower end in FIG. 2). A bearing metal (23) is fitted onto the inner periphery of the upper part of the auxiliary bearing (22). The auxiliary bearing (22) rotatably supports the main shaft portion (14) of the drive shaft (11) via the bearing metal (23). The auxiliary bearing (22) is housed in the casing (20). The auxiliary bearing (22) is arranged on the opposite side of the electric motor (30) from the housing (50). In this embodiment, the auxiliary bearing (22) is arranged below the electric motor (30).

[0046] The sub-bearing (22) is fixed inside the casing (20). More specifically, the outer peripheral surface of the sub-bearing (22) is fixed to the inner peripheral surface of the trunk portion (20a). The sub-bearing (22) is welded to the trunk portion (20a) via a welding pin (81) and a joint (82). In this embodiment, the casing (20) and the sub-bearing (22) are not fixed to each other by fitting.

[0047] (2-8) Oil Supply Passage An oil supply passage (16) is formed inside the drive shaft (11). The oil supply passage (16) extends vertically from the lower end to the upper end of the drive shaft (11). A pump (25) is connected to the lower end of the drive shaft (11). The pump (25) is, for example, a positive displacement pump. The lower end of the pump (25) is immersed in the oil reservoir (21).

[0048] The pump (25) draws up lubricating oil from the oil reservoir (21) as the drive shaft (11) rotates, and delivers the lubricating oil to the oil supply passage (16). The oil supply passage (16) supplies the lubricating oil from the oil reservoir (21) to the sliding surface between the auxiliary bearing (22) and the drive shaft (11), the sliding surface between the upper bearing (51) and the drive shaft (11), and also to the sliding surface between the boss portion (73) and the drive shaft (11). The oil supply passage (16) opens to the upper end surface of the drive shaft (11) and supplies the lubricating oil above the drive shaft (11).

[0049] (3) Operation of Compressor The operation of the scroll compressor (10) will be described.

[0050] (3-1) Flow of Refrigerant In Fig. 2, when the electric motor (30) is operated, the drive shaft (11) is driven to rotate. The orbiting scroll (70) orbits in association with the rotation of the drive shaft (11). Here, the orbiting scroll (70) is prevented from rotating on its own axis by the Oldham coupling (45), and therefore rotates eccentrically about the axis of the drive shaft (11).

[0051] When the orbiting scroll (70) orbits, the refrigerant that has flowed into the suction port (64) through the suction pipe (12) is compressed in the fluid chamber (S). The high-pressure gas refrigerant compressed in the fluid chamber (S) is discharged from the discharge port (65) and flows into the lower space (24) through a discharge passage (56) formed in the housing (50). The high-pressure gas refrigerant in the lower space (24) is discharged to the outside of the casing (20) through the discharge pipe (13).

[0052] (3-2) Flow of Lubricating Oil As the drive shaft (11) rotates, the high-pressure lubricating oil in the oil reservoir (21) is sucked up by the pump (25), flows upward through the oil supply passage (16) of the drive shaft (11), and flows out from the opening at the upper end of the eccentric portion (15) of the drive shaft (11) into the inside of the boss portion (73) of the orbiting scroll (70).

[0053] The lubricating oil supplied to the boss (73) flows out into the recess (53) of the housing (50) through the gap between the eccentric portion (15) of the drive shaft (11) and the boss (73).

[0054] The lubricating oil accumulated in the recess (53) is supplied to the sliding surfaces of the fixed scroll (60) and the orbiting scroll (70) through oil passages (not shown) formed in the housing (50) and the fixed scroll (60), and then returned to the oil reservoir (21).

[0055] (4) Fixing Structure of Housing The fixing structure of the housing (50) will be described.

[0056] In this embodiment, the housing (50) corresponds to the fixed object (F) of the present disclosure. The fixed object (F) is housed in the casing (20) and fixed to the body (20a) of the casing (20).

[0057] As shown in FIG. 3 , the housing (50) has a contact area (A) that comes into contact with the inner circumferential surface of the trunk portion (20a) of the casing (20). The contact area (A) is formed on the outer circumferential surface of the annular portion (52) of the housing (50). The contact area (A) of the housing (50) is the area on the outer circumferential surface of the annular portion (52) excluding the notched portion (55). The contact area (A) of the housing (50) is formed in an arc shape when viewed in the axial direction. In other words, the housing (50) of this embodiment has one contact area (A). The housing (50) is fixed to the casing (20) at the contact area (A) by welding and fitting.

[0058] (4-1) Welded Portions As shown in FIGS. 2 and 3 , the scroll compressor (10) has a plurality of welded portions (80) (four in this embodiment) connecting the trunk portion (20a) and the housing (50). At the welded portions (80), the trunk portion (20a) and the housing (50) are fixed together via weld pins (81) and joints (82). The welded portions (80) are formed by press-fitting the welded pins (81) into holes formed in the housing (50) while the housing (50) is fixed to the casing (20) and welding the welded pins (81) to the trunk portion (20a). The joints (82) are formed by melting the welded pins (81) and the trunk portion (20a) during welding.

[0059] As shown in Fig. 3, the welds (80) are arranged at predetermined intervals along the circumferential direction of the trunk portion (20a). In other words, four welds (80) are provided along the circumferential direction in one contact area (A). In this manner, the scroll compressor (10) has a plurality of welds (80) provided along the circumferential direction, thereby preventing the housing (50) from shifting relative to the casing (20).

[0060] (4-2) Fitting Relationship The outer diameter of the annular portion (52) of the housing (50) and the inner diameter of the body portion (20a) of the casing (20) are fitted together, so that the housing (50) is held in the casing (20).

[0061] In the scroll compressor (10) of this embodiment, the fit between the outer diameter of the housing (50) and the inner diameter of the casing (20) differs between the assembled state and the rated operation state of the scroll compressor (10). The fit between the outer diameter of the housing (50) and the inner diameter of the casing (20) in the assembled state and the rated operation state of the scroll compressor (10) will be described in detail with reference to FIGS. 4 and 5.

[0062] The term "assembled state" used herein refers to a state in which the scroll compressor (10) is not connected to the refrigerant circuit (1a) and the pressure inside the casing (20) is the same as atmospheric pressure. The term "rated operating state" used herein refers to a state in which the scroll compressor (10) is connected to the refrigerant circuit (1a) and is operated under rated conditions.

[0063] The rated conditions here refer to the rated conditions specified in ISO 5151 and JIS B 8615. The high-pressure pressure in the casing (20) under these rated conditions varies depending on the type of refrigerant charged in the refrigerant circuit (1a). For example, when the refrigerant is R32, the high-pressure pressure under the rated conditions is 2.7 MPaG or more and 3.4 MPaG or less. When the refrigerant is R410A, the high-pressure pressure under the rated conditions is 2.6 MPaG or more and 3.3 MPaG or more.

[0064] The dimensional tolerances of the shaft and the hole relative to the reference dimensions of the shaft and the hole in each fitting relationship are different. Here, the reference dimensions refer to the nominal sizes specified in ISO 286-1:2010. In this embodiment, the reference dimensions φ of the outer diameter of the annular portion (52) and the inner diameter of the body portion (20a) are 145 mm. The refrigerant filled in the refrigerant circuit (1a) of this embodiment is R32, and the thickness of the casing (20) is 4.4 mm.

[0065] 4 is an enlarged view showing the vicinity of the contact area (A) in the assembled state of the scroll compressor (10). As shown in FIG. 4, in the assembled state of the scroll compressor (10), there is no gap between the inner circumferential surface of the body portion (20a) and the outer circumferential surface of the annular portion (52), and they are in contact with each other.

[0066] In the assembled state of the scroll compressor (10) of this embodiment, the inner diameter of the trunk portion (20a) and the outer diameter of the annular portion (52) have a relationship in which the combination of the tolerance class of the hole and the tolerance class of the shaft (hole / shaft) defined in ISO 286-1:2010 (hereinafter referred to as ISO 286) corresponds to H7 / n6. In other words, in the assembled state, the tolerance class of the inner diameter of the trunk portion (20a) corresponds to H7 in the tolerance class of the hole defined in ISO 286, and the tolerance class of the outer diameter of the annular portion (52) corresponds to n6 in the tolerance class of the shaft defined in ISO 286.

[0067] The above fitting relationship is a so-called locational transition fit-interference, in which the parts cannot move relative to each other.

[0068] In this embodiment, the dimensional tolerance range of the scroll compressor (10) in an assembled state (specifically, when the pressure inside the casing (20) is the same as atmospheric pressure) is 14 μm or more and 43 μm or less (14 μm to 43 μm) with respect to the reference dimension. Specifically, in this embodiment, the minimum allowable dimension in the assembled state is 145.014 mm, and the maximum allowable dimension is 145.043 mm. This fitting relationship corresponds to a so-called "tight fit."

[0069] 5 is an enlarged view showing the vicinity of the contact area (A) in the rated operation state of the scroll compressor (10). As shown in FIG. 5, in the rated operation state of the scroll compressor (10), a small gap is formed between the inner circumferential surface of the body portion (20a) and the outer circumferential surface of the annular portion (52).

[0070] When the scroll compressor (10) starts operating, the gas refrigerant sucked into the casing (20) is compressed in the compression mechanism (40). The compressed gas refrigerant is discharged into the casing (20), thereby increasing the pressure inside the casing (20). The increase in the pressure inside the casing (20) causes the casing (20) to expand. This forms a small gap between the inner circumferential surface of the body portion (20a) and the outer circumferential surface of the annular portion (52).

[0071] 5, for ease of understanding, the inner peripheral surface of the body portion (20a) and the outer peripheral surface of the annular portion (52) are not in contact with each other. However, in reality, a local gap (G) is formed between the inner peripheral surface of the body portion (20a) and the outer peripheral surface of the annular portion (52). In other words, the inner peripheral surface of the body portion (20a) and the outer peripheral surface of the annular portion (52) have portions where they are in contact with each other and portions where they are not in contact with each other and a small gap (G) is formed. The reason why a local gap (G) is formed between the inner peripheral surface of the body portion (20a) and the outer peripheral surface of the annular portion (52) is that, strictly speaking, the inner shape of the body portion (20a) and the outer shape of the annular portion (52) are each non-circular when viewed in the axial direction, the inner peripheral surface of the body portion (20a) may be slightly inclined in the axial direction, and so on.

[0072] In the rated operating state of the scroll compressor (10) of this embodiment, the inner diameter of the body portion (20a) and the outer diameter of the annular portion (52) have a relationship in which the combination of the tolerance class of the hole and the tolerance class of the shaft (hole / shaft) corresponds to H7 / g6, as defined in ISO 286. In other words, in the rated operating state, the tolerance class of the inner diameter of the body portion (20a) corresponds to H7 in the tolerance class of the hole defined in ISO 286, and the tolerance class of the outer diameter of the annular portion (52) corresponds to g6 in the tolerance class of the shaft defined in ISO 286.

[0073] The above fitting relationship is a so-called sliding fit - constrained fitting relationship, in which the parts can move relatively to each other.

[0074] The dimensional tolerance range of the scroll compressor (10) of this embodiment in a rated operating state (specifically, when the pressure inside the casing (20) is 2.5 MPa) is −43 μm or more and 14 μm or less (−43 μm to 14 μm) with respect to the reference dimension. Specifically, the minimum allowable dimension in the rated operating state of this embodiment is 144.957 mm, and the maximum allowable dimension is 145.014 mm. This fitting relationship corresponds to a so-called "loose fit." More specifically, this fitting relationship corresponds to a so-called "precise rotation fit."

[0075] In this way, when the scroll compressor (10) changes from the assembled state to the rated operating state, the fitting relationship between the inner diameter of the body portion (20a) and the outer diameter of the annular portion (52) changes.

[0076] As described above, in the rated operation state of the scroll compressor (10), a local gap (G) is formed between the inner circumferential surface of the trunk portion (20a) and the outer circumferential surface of the annular portion (52), and the plurality of welds (80) provided in the circumferential direction suppress large displacement between the casing (20) and the housing (50). Therefore, the housing (50) can move slightly relative to the casing (20).

[0077] As a result, in the area where a gap (G) is formed between the inner peripheral surface of the body portion (20a) and the outer peripheral surface of the annular portion (52), the housing (50) vibrates due to the vibrations transmitted from the compression mechanism (40) to the housing (50), and the energy due to the vibrations is converted into kinetic energy, thereby attenuating the vibrations transmitted from the compression mechanism (40).

[0078] In addition, in the area where the inner peripheral surface of the body portion (20a) and the outer peripheral surface of the annular portion (52) are in contact with each other, the inner peripheral surface of the body portion (20a) and the outer peripheral surface of the annular portion (52) rub against each other, converting the energy due to vibration into thermal energy due to friction, thereby attenuating the vibration transmitted from the compression mechanism (40).

[0079] In this manner, when the scroll compressor (10) is in a rated operating state, a local gap (G) is formed between the inner peripheral surface of the body portion (20a) and the outer peripheral surface of the annular portion (52), causing the housing (50) to move slightly, thereby effectively damping vibrations generated in the compression mechanism (40), thereby reducing noise generated in the scroll compressor (10).

[0080] The reference dimensions, dimensional tolerance ranges, refrigerant type, and casing thickness in this embodiment are examples. The degree of expansion of the casing (20) during rated operation of the scroll compressor (10) varies depending on the type of refrigerant filled in the refrigerant circuit (1a), the thickness of the casing (20), etc.

[0081] FIG. 6 shows terms indicating the fitting relationship, tolerance classes defined in ISO 286 that correspond to the fitting relationship, and dimensional tolerance ranges for a reference dimension of φ145 mm that correspond to the tolerance classes.

[0082] As shown in FIG. 6, in the assembled state of the scroll compressor (10) of this embodiment, the inner diameter of the body portion (20a) and the outer diameter of the annular portion (52) may have a fitting relationship that corresponds to a combination of the tolerance class of the hole and the tolerance class of the shaft (hole / shaft) defined in ISO 286 of H7 / r6, H7 / s6, or H8 / u8.

[0083] The above-mentioned fitting relationship is a fitting relationship indicated by a so-called locational interference fit, medium drive fit, or force fit. These fitting relationships are relationships in which the parts cannot move relative to each other. The above-mentioned fitting relationship corresponds to a so-called "tight fit."

[0084] As shown in FIG. 6 , the inner diameter of the body portion (20 a) and the outer diameter of the annular portion (52) in the rated operating state of the scroll compressor (10) of this embodiment may have a fitting relationship corresponding to a combination of the tolerance class of the hole and the tolerance class of the shaft (hole / shaft) defined in ISO 286 of H8 / f7, F8 / h9, H7 / f7, F8 / h6, or G7 / h6.

[0085] The above fitting relationships are those shown as so-called close running fit, sliding fit - free, or sliding fit - constrained. These fitting relationships allow the parts to move relative to each other. These fitting relationships correspond to so-called "loose fit."

[0086] Even when the inner diameter of the body portion (20a) and the outer diameter of the annular portion (52) in the rated operating state of the scroll compressor (10) are in a fit relationship as specified in ISO 286, a local gap (G) is formed between the inner surface of the body portion (20a) and the outer surface of the annular portion (52), just as in the case where the combination of the hole tolerance class and the shaft tolerance class (hole / shaft) specified in ISO 286 is H7 / g6.

[0087] As a result, the energy of vibrations transmitted from the compression mechanism (40) to the housing (50) during operation of the scroll compressor (10) is converted into kinetic energy due to movement of the housing (50) or into thermal energy due to friction between the housing (50) and the casing (20), thereby damping the vibrations transmitted from the compression mechanism (40), thereby reducing the noise generated by the scroll compressor (10).

[0088] (5) Features (5-1) Feature 1 In the rated operating state of the scroll compressor (10), the inner diameter of the body (20a) of the casing (20) and the outer diameter of the annular portion (52) of the housing (50) are in a fitting relationship that corresponds to the combination of the hole tolerance class and the shaft tolerance class (hole / shaft) defined in ISO 286, which is H8 / f7, F8 / h9, H7 / f7, F8 / h6, H7 / g6, or G7 / h6.

[0089] During rated operation of the scroll compressor (10), the body portion (20a) expands as the refrigerant pressure in the casing (20) increases, and the inner diameter of the body portion (20a) and the outer diameter of the annular portion (52) achieve the fit defined by ISO 286. This fit creates a local gap (G) between the inner circumferential surface of the body portion (20a) and the outer circumferential surface of the annular portion (52). This allows the housing (50) to move slightly relative to the casing (20). This converts vibration energy transmitted from the compression mechanism (40) to the housing (50) during operation of the scroll compressor (10) into kinetic energy due to the movement of the housing (50) or thermal energy due to friction between the housing (50) and the casing (20), thereby damping the vibration transmitted from the compression mechanism (40). As a result, noise generated by the scroll compressor (10) can be reduced.

[0090] (5-2) Feature 2 The inner diameter of the body portion (20a) and the outer diameter of the annular portion (52) in the assembled state of the scroll compressor (10) have a fitting relationship in which the combinations of the hole tolerance class and the shaft tolerance class (hole / shaft) defined in ISO 286 correspond to H7 / n6, H7 / r6, H7 / s6, and H8 / u8.

[0091] When the scroll compressor (10) is assembled, the inner diameter of the body portion (20a) and the outer diameter of the annular portion (52) are in the above-mentioned fitting relationship defined by ISO 286, so that the annular portion (52) of the housing (50) is fixed to the body portion (20a) by the welded portion (80) and the fitting.

[0092] Furthermore, by forming the welded portion (80) after holding the annular portion (52) of the housing (50) to the body portion (20a) by the above-mentioned fitting relationship defined in ISO 286, displacement of the housing (50) when forming the welded portion (80) is suppressed, thereby improving the ease of assembly.

[0093] (5-3) Feature 3 The fixed object (F) is the housing (50) of the scroll compressor (10). The housing (50) supports the compression mechanism (40), and therefore vibrations of the compression mechanism (40) are easily transmitted to the housing (50). By applying the above-described fitting relationship defined in ISO 286 between the inner diameter of the body portion (20a) and the outer diameter of the housing (50), the noise of the compressor can be further reduced.

[0094] (5-4) Feature 4 At the welded portion (80), the body portion (20a) of the casing (20) and the annular portion (52) of the housing (50) are welded together via a welding pin (81).

[0095] (5-5) Feature 5 The refrigeration system (1) includes the scroll compressor (10) of this embodiment and a refrigerant circuit (1a) through which the refrigerant compressed by the scroll compressor (10) flows. This makes it possible to provide a refrigeration system (1) with reduced noise from the scroll compressor (10).

[0096] (6) Modifications The above embodiment may be modified as follows: In the following description, differences from the above embodiment will be mainly explained.

[0097] (6-1) Modification 1 In the scroll compressor (10) of this embodiment, the fixed object member (F) may be the auxiliary bearing (22). The auxiliary bearing (22) corresponds to the support member (B) of the present disclosure. Since the auxiliary bearing (22) is connected to the compression mechanism (40) via the drive shaft (11), vibrations generated in the compression mechanism (40) are transmitted to the auxiliary bearing (22) via the drive shaft (11).

[0098] As shown in Fig. 7, the sub-bearing (22) is formed so as to traverse the casing (20). The sub-bearing (22) has an annular portion (22a) formed in the center and three protrusions (22b) protruding radially outward from the annular portion. The drive shaft (11) is inserted through the center of the annular portion (22a). The three protrusions (22b) are arranged at predetermined intervals in the circumferential direction.

[0099] The sub-bearing (22) is formed with a plurality of contact areas (A) (three in this modification) that come into contact with the inner circumferential surface of the body portion (20a) of the casing (20). The contact areas (A) of the sub-bearing (22) are formed on the outer circumferential surface of each protrusion (22b). Each contact area (A) of the sub-bearing (22) is formed in an arc shape when viewed in the axial direction.

[0100] In this modification, when the scroll compressor (10) is not operating, the auxiliary bearing (22) is fixed to the casing (20) by welding and fitting at the contact area (A). In this modification, three welds (80) are arranged at predetermined intervals along the circumferential direction of the body portion (20a). Each of the three welds (80) is provided at a respective contact area (A). In other words, one weld (80) is provided for each contact area (A). Since the scroll compressor (10) has a plurality of welds (80) arranged along the circumferential direction, it is possible to prevent the auxiliary bearing (22) from shifting relative to the casing (20).

[0101] In this modified example, the inner diameter of the body portion (20a) and the outer diameter of the annular portion (52) in the assembled state of the scroll compressor (10) are in a fitting relationship that corresponds to the combinations of hole tolerance classes and shaft tolerance classes (hole / shaft) specified in ISO 286: H7 / n6, H7 / r6, H7 / s6, and H8 / u8.

[0102] In this modified example, the inner diameter of the body portion (20a) and the outer diameter of the annular portion (52) in the rated operating state of the scroll compressor (10) are in a fitting relationship that corresponds to the combination of the hole tolerance class and the shaft tolerance class (hole / shaft) defined in ISO 286: H8 / f7, F8 / h9, H7 / f7, F8 / h6, H7 / g6, or G7 / h6.

[0103] As a result, even when the fixed object member (F) is the auxiliary bearing (22), a local gap (G) is formed between the inner peripheral surface of the body portion (20a) of the casing (20) and the outer peripheral surface of each protrusion portion (22b) of the auxiliary bearing (22), thereby achieving the same effect as in the above embodiment.

[0104] Other Embodiments The above-described embodiment may be configured as follows.

[0105] The compressor (10) of the above embodiment may be a rotary compressor. In this case, the fixed object member (F) may be a front head, a cylinder, or a rear head. The cylinder is a member that constitutes the compression mechanism and forms a fluid chamber together with the piston. The front head and the rear head are bearing support members that rotatably support the drive shaft. The front head or the rear head corresponds to the support member (B) of the present disclosure. The cylinder, the front head, and the rear head are formed in a cylindrical shape. The outer peripheral surfaces of the cylinder, the front head, and the rear head are fixed to the inner peripheral surface of the casing.

[0106] Furthermore, when the compressor (10) of the above embodiment is a rotary compressor, the support member (B) may be a mounting plate that supports the front head body on the casing. The mounting plate is a component of the front head. When the front head has a mounting plate, the front head is fixed to the casing via the mounting plate. The mounting plate is, for example, a plate-like member that is formed along the inner periphery of the casing and around the entire periphery, and has a substantially L-shaped longitudinal cross section.

[0107] Although the embodiments and modifications have been described above, it will be understood that various modifications in form and details are possible without departing from the spirit and scope of the claims. Furthermore, elements of the above embodiments, modifications, and other embodiments may be combined or substituted as appropriate.

[0108] The above-mentioned descriptions such as "first," "second," "third," etc. are used to distinguish the words to which these descriptions are attached, and do not limit the number or order of the words.

[0109] INDUSTRIAL APPLICABILITY As described above, the present disclosure is useful for compressors and refrigeration devices.

[0110] REFRIGERATION SYSTEM 1a REFRIGERATOR CIRCUIT 10 COMPRESSOR (SCROLL COMPRESSOR) 11 DRIVE SHAFT 20 CASING 20a BODY 40 COMPRESSION MECHANISM 50 HOUSING (MAINTENANCE HOUSING) 60 FIXED SCROLL 70 ORBITING SCROLL 80 WELDED PORTION 81 WELD PIN (PIN) B SUPPORT MEMBER F MEMBER TO BE FIXED

Claims

DEPCT681. A compressor which is assembled with: an outer frame (20) with a tubular cylinder (20a); a target attachment (F) contained in the outer frame (20) and attached to the cylinder (20a); and a number of welds (80) arranged in the circumferential direction of the cylinder (20a), which weld (80) connect the cylinder (20a) and the target attachment (F), with the target attachment (F) serving as a support (B) which is arranged to support the compression mechanism (40) which is arranged A refrigerant compression or drive shaft (11) connected to a rotatable compression mechanism (40) with an inner diameter of the cylinder (20a) and an outer diameter of the target mounting part (F) in the specified operating state of the compressor (10) which has a wear relationship in which the combination of the tolerance class for the bore and the tolerance class for the shaft (bore / shaft) specified in ISO286 corresponds to H8 / f7, F8 / h9, H7 / f7, F8 / h6, H7 / g6 or G7 / h62.A compressor under claim 1 in which the inner diameter of the cylinder (20a) and the outer diameter of the target part to be fastened (F) in the assembled state of the compressor (10) have a wear relationship in which the combination of the tolerance class for the bore and the tolerance class for the shaft (bore / shaft) specified in ISO286 corresponds to H7 / n6, H7 / r6, H7 / s6 or H8 / u83. A compressor under claim 1 or 2 which is further assembled with: a main bearing housing (50) as a support (B) in which the body The main bearing housing (50) is configured to accommodate the compression mechanism (40), in which the compression mechanism (40) includes a stationary volute element (60) and a movable volute element (70) which are configured to mesh together with the stationary volute element (60) and the target attachment element (F) is the main bearing housing (50).

4. Any compressor under claims 1 to 3 in which the weld (80) of the cylinder (20a) and the target attachment element (F) are welded together via a rivet (81). 5.The refrigeration equipment consists of: a compressor (10) according to any of the claims 1 through 4; and a refrigerant circuit (1a) through which the refrigerant compressed by the compressor (10) flows.

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