Rotary compressor and refrigeration device

Abstract

To suppress the generation of warpage at a drive shaft caused by a centrifugal force of a balance weight.SOLUTION: A drive shaft (11) has a balancing weight (18). The balancing weight (18) is arranged between a compression mechanism (50) and a motor (25). A housing (30) is arranged between the compression mechanism (50) and the motor (25). The housing (30) has a first support part (35) and a second support part (45). The first support part (35) supports the drive shaft (11) on a side closer to the compression mechanism (50) as compared to the balancing weight (18). The second support part (45) supports the drive shaft (11) on a side closer to the motor (25) as compared to the balancing weight (18).SELECTED DRAWING: Figure 2

Description

[Technical field]

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

[0002] Patent Document 1 discloses a scroll compressor including a compression mechanism that compresses a refrigerant, a drive shaft (crank shaft) that drives the compression mechanism, and an electric motor that rotates the drive shaft.

[0003] An upper balance weight is integrally formed with the drive shaft. The upper balance weight is disposed between a housing of the compression mechanism and a rotor of the electric motor. The drive shaft is rotatably supported by an upper bearing and a lower bearing provided in the housing. The drive shaft is connected to the rotor of the electric motor between the upper bearing and the lower bearing. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2016-050549 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the scroll compressor of Patent Document 1, the upper bearing and the lower bearing are arranged at a distance from each other across the electric motor, and if the centrifugal force of the upper balance weight becomes large, there is a risk that the drive shaft will bend between the upper bearing and the lower bearing.

[0006] An object of the present disclosure is to suppress deflection of the drive shaft caused by the centrifugal force of the balance weight. [Means for solving the problem]

[0007] A first aspect of the present disclosure is a rotary compressor including a compression mechanism (50) that compresses a refrigerant, a drive shaft (11) that drives the compression mechanism (50), and a motor (25) that rotates the drive shaft (11), and further including a support member (30) that is arranged between the compression mechanism (50) and the motor (25) and rotatably supports the drive shaft (11), and a balance weight (18) that is provided on the drive shaft (11) and arranged between the compression mechanism (50) and the motor (25), and the support member (30) has a first support portion (35) that supports the drive shaft (11) on the compression mechanism (50) side of the balance weight (18), and a second support portion (45) that supports the drive shaft (11) on the motor (25) side of the balance weight (18).

[0008] In the first aspect, by supporting the drive shaft (11) on both the compression mechanism (50) side and the motor (25) side of the balance weight (18), it is possible to prevent the drive shaft (11) from bending due to the centrifugal force of the balance weight (18).

[0009] In a second aspect of the present disclosure, in the rotary compressor of the first aspect, an axial length L1 of a portion of the drive shaft (11) supported by the first support portion (35) and an axial length L2 of a portion of the drive shaft (11) supported by the second support portion (45) satisfy the condition L1≧L2.

[0010] In the second aspect, the axial length of the portion of the drive shaft (11) supported by the first support portion (35) is set to be the same as or longer than the axial length of the portion of the drive shaft (11) supported by the second support portion (45). This increases the contact area between the first support portion (35) located closer to the compression mechanism (50) and the drive shaft (11), thereby making it possible to effectively suppress bending of the drive shaft (11) due to the centrifugal force of the balance weight (18).

[0011] A third aspect of the present disclosure is a rotary compressor of the first or second aspect, further comprising a first bearing (37) provided on the first support portion (35) and supporting the drive shaft (11), and a second bearing (47) provided on the second support portion (45) and supporting the drive shaft (11).

[0012] In the third aspect, the drive shaft (11) is supported by the first bearing (37) and the second bearing (47), so that the drive shaft (11) can be smoothly rotated.

[0013] A fourth aspect of the present disclosure is a rotary compressor of the first or second aspect, comprising a casing (20) that houses the compression mechanism (50), and the support member (30) has a first housing body (31) having the first support portion (35) and a second housing body (41) having the second support portion (45), the first housing body (31) being fixed to the casing (20), and the second housing body (41) being fixed to the first housing body (31).

[0014] In the fourth aspect, the first housing body (31) having the first support portion (35) and the second housing body (41) having the second support portion (45) are formed from separate members, thereby improving the ease of assembly. Furthermore, by combining the first housing body (31) and the second housing body (41), the balance weight (18) is surrounded by the first housing body (31) and the second housing body (41), so that the flow of the refrigerant in the casing (20) is prevented from being disturbed by the rotation of the balance weight (18).

[0015] A fifth aspect of the present disclosure is a refrigeration system including the rotary compressor (10) of the first or second aspect, and a refrigerant circuit (1a) through which a refrigerant compressed by the rotary compressor (10) flows.

[0016] In a fifth aspect, a refrigeration system (1) including a rotary compressor (10) can be provided. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a refrigerant circuit diagram showing the configuration of a refrigeration device according to this embodiment. [Diagram 2] FIG. 2 is a vertical sectional view showing the configuration of the scroll compressor. [Diagram 3] FIG. 3 is a side cross-sectional view showing the configuration of the first housing body and the second housing body. [Figure 4] FIG. 4 is a vertical sectional view showing the configuration of a scroll compressor according to this modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] As shown in Fig. 1, a scroll compressor (10) serving as a rotary compressor is provided in a refrigeration system (1). The refrigeration system (1) has a refrigerant circuit (1a) filled with a refrigerant. The refrigerant circuit (1a) has a scroll 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.

[0019] The refrigeration system (1) is an air conditioner. The air conditioner may be a cooling only machine, a heating only machine, or an air conditioner that switches between cooling and heating. In this case, the air conditioner has a switching mechanism (e.g., a four-way switching valve) that switches the circulation direction of the refrigerant. The refrigeration system (1) may be a water heater, a chiller unit, a cooling device that cools the air inside a storage unit, or the like. The cooling device cools the air inside a refrigerator, a freezer, a container, or the like.

[0020] As shown in Fig. 2, the scroll compressor (10) includes a casing (20), a motor (25), and a compression mechanism (50). The casing (20) is formed in a vertically elongated cylindrical shape and configured as a sealed dome type. The casing (20) houses the motor (25) and the compression mechanism (50).

[0021] The motor (25) has a stator (26) and a rotor (27). The stator (26) is fixed to the inner circumferential surface of the casing (20). The rotor (27) is disposed inside the stator (26). The drive shaft (11) passes through the rotor (27). The rotor (27) is fixed to the drive shaft (11). A lower weight (28) is provided below the rotor (27). The lower weight (28) is covered by a lower cover (29).

[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 of the casing (20). An inlet end of the discharge pipe (13) communicates with a discharge space (23) above the motor (25).

[0023] The drive shaft (11) extends vertically along the central axis of the casing (20). The drive shaft (11) has a main shaft portion (14), an eccentric portion (15), and a balance weight (18).

[0024] The eccentric portion (15) is provided at an upper end of the main shaft portion (14). The balance weight (18) is disposed between the compression mechanism (50) and the motor (25).

[0025] A lower portion of the main shaft portion (14) is rotatably supported by a lower bearing (22). The lower bearing (22) is fixed to an inner circumferential surface of the casing (20). The lower bearing (22) is provided with, for example, a positive displacement pump (24). The main shaft portion (14) passes through a housing (30) serving as a support member, and is rotatably supported by a first support portion (35) and a second support portion (45) of the housing (30), which will be described later.

[0026] A housing (30) is fixed to the casing (20). The housing (30) is disposed above the motor (25). A compression mechanism (50) is disposed above the housing (30).

[0027] The housing (30) has a first housing body (31) and a second housing body (41). The first housing body (31) is disposed closer to the compression mechanism (50) than the second housing body (41).

[0028] The first housing body (31) is fixed to the inner circumferential surface of the casing (20) by, for example, shrink fitting. The first housing body (31) may also be fixed to the inner circumferential surface of the casing (20) by bolting, welding, or the like.

[0029] The first housing body (31) is provided with a recess (32), a first fitting portion (34), and a first support portion (35). The recess (32) is provided by recessing a portion of the upper surface of the first housing body (31). A boss portion (73) of the movable scroll (70), which will be described later, is disposed in the recess (32).

[0030] The first fitting portion (34) is provided by a part of the lower surface of the first housing body (31) protruding. A second fitting portion (44) (described later) of the second housing body (41) is fitted into the first fitting portion (34).

[0031] The first support part (35) supports the drive shaft (11) on the compression mechanism (50) side relative to the balance weight (18). The first support part (35) is configured below the bottom surface of the recess (32) in the first housing body (31). A first through hole (36) is provided in the first support part (35) passing through in the axial direction. A cylindrical first bearing (37) is provided in the first through hole (36). The first bearing (37) is, for example, a metal bearing. The first bearing (37) may be configured as a rolling bearing.

[0032] The first support portion (35) rotatably supports the drive shaft (11) via a first bearing (37). Note that the drive shaft (11) may be rotatably supported by the inner circumferential surface of the first through hole (36) of the first support portion (35) without providing the first bearing (37).

[0033] A screw hole (38) is provided in the lower surface of the first housing body (31). The screw holes (38) are provided at intervals in the circumferential direction of the first housing body (31).

[0034] The second housing body (41) is provided with an accommodating recess (42), a flange portion (43), a second fitting portion (44), and a second support portion (45).

[0035] The accommodating recess (42) is provided by recessing a portion of the upper surface of the second housing body (41). The accommodating recess (42) accommodates the balance weight (18). The balance weight (18) is rotatable within the accommodating recess (42).

[0036] The flange portion (43) projects radially outward from the upper end portion of the second housing body (41). The flange portion (43) has a plurality of insertion holes (48) formed therein corresponding to the plurality of screw holes (38) of the first housing body (31).

[0037] The second fitting portion (44) extends along the outer circumferential edge of the flange portion (43) and protrudes upward. The second fitting portion (44) fits into the first fitting portion (34), thereby restricting radial movement of the second housing body (41) relative to the first housing body (31).

[0038] The second support portion (45) supports the drive shaft (11) closer to the motor (25) than the balance weight (18). The second support portion (45) is configured in a portion of the second housing body (41) that is lower than the bottom surface of the receiving recess (42). The second support portion (45) is provided with a second through hole (46) that penetrates in the axial direction. A cylindrical second bearing (47) is provided in the second through hole (46). The second bearing (47) is, for example, a metal bearing. The second bearing (47) may be a rolling bearing.

[0039] The second support portion (45) rotatably supports the drive shaft (11) via a second bearing (47). Note that the drive shaft (11) may be rotatably supported by the inner circumferential surface of the second through hole (46) of the second support portion (45) without providing the second bearing (47).

[0040] By combining a first housing body (31) having a first support portion (35) with a second housing body (41) having a second support portion (45), the balance weight (18) is surrounded by the first housing body (31) and the second housing body (41).

[0041] Specifically, as shown in Fig. 3, the second fitting portion (44) of the second housing body (41) is fitted into the first fitting portion (34) of the first housing body (31). Then, the fastening bolts (49) are inserted into the insertion holes (48) from the flange portion (43) side and screwed into the screw holes (38), thereby fastening and fixing the second housing body (41) to the first housing body (31).

[0042] This enables the second support portion (45) to be positioned in the radial direction relative to the first support portion (35) and prevents the second support portion (45) from moving in the radial direction. Note that the second support portion (45) may be positioned in the first support portion (35) by, for example, providing a positioning pin (not shown) without providing the first fitting portion (34) and the second fitting portion (44).

[0043] Here, it is preferable to set the axial length L1 of the portion of the drive shaft (11) supported by the first support portion (35) and the axial length L2 of the portion of the drive shaft (11) supported by the second support portion (45) so as to satisfy the condition L1 ≧ L2.

[0044] In this way, by increasing the contact area between the first bearing (37) of the first support part (35) arranged closer to the compression mechanism (50) and the drive shaft (11), it is possible to effectively suppress bending of the drive shaft (11) due to the centrifugal force of the balance weight (18).

[0045] The compression mechanism (50) includes a fixed scroll (60) and a movable scroll (70). The fixed scroll (60) is fixed to an upper surface of the housing (30). The movable scroll (70) is disposed between the fixed scroll (60) and the housing (30).

[0046] The fixed scroll (60) has a fixed end plate (61), a fixed side wrap (62), and an outer circumferential wall (63). The outer circumferential wall (63) is formed in a substantially cylindrical shape. The outer circumferential wall (63) stands on the outer edge of the front surface (the lower surface in FIG. 2) of the fixed end plate (61).

[0047] The fixed-side wrap (62) is formed in a spiral shape and is provided upright inside the outer circumferential wall (63) of the fixed-side end plate (61).

[0048] The fixed scroll (60) is fixed to the housing (30).

[0049] The movable scroll (70) has a movable end plate (71), a movable wrap (72), and a boss portion (73). The movable wrap (72) is formed in a spiral shape. The movable wrap (72) is formed on the upper surface of the movable end plate (71). The movable wrap (72) meshes with the fixed wrap (62).

[0050] The boss portion (73) is formed at the center of the lower surface of the movable end plate (71). The eccentric portion (15) of the drive shaft (11) is inserted into the boss portion (73) to couple the drive shaft (11).

[0051] An Oldham coupling (55) is provided at the upper part of the housing (30). The Oldham coupling (55) prevents the movable scroll (70) from rotating on its axis. The Oldham coupling (55) is provided with a key (56). The key (56) protrudes from the lower surface of the movable end plate (71) of the movable scroll (70). A key groove (57) is formed in the lower surface of the movable end plate (71) of the movable scroll (70). The key (56) of the Oldham coupling (55) is slidably fitted into the key groove (57).

[0052] Although not shown, a key is also provided on the housing (30) side of the Oldham coupling (55), and the key on the housing (30) side is slidably fitted into a key groove (not shown) of the housing (30).

[0053] The compression mechanism (50) has a fluid chamber (S) into which the refrigerant flows. The fluid chamber (S) is formed between the fixed scroll (60) and the movable scroll (70). The movable scroll (70) is disposed such that the movable wrap (72) meshes with the fixed wrap (62) of the fixed scroll (60). Here, the lower surface of the outer circumferential wall (63) of the fixed scroll (60) serves as an opposing surface to the movable scroll (70). In addition, the upper surface of the movable end plate (71) of the movable scroll (70) serves as an opposing surface to the fixed scroll (60).

[0054] 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).

[0055] 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 an 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 discharge space (23) through a passage (not shown) formed in the housing (30).

[0056] 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). The lower end of the drive shaft (11) is connected to a pump (24). The lower end of the pump (24) is immersed in an oil reservoir (21). The pump (24) draws up lubricating oil from the oil reservoir (21) as the drive shaft (11) rotates, and transports 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 lower bearing (22) and the drive shaft (11), the sliding surface between the first bearing (37) and the drive shaft (11), and the sliding surface between the second bearing (47) and the drive shaft (11), as well as to the sliding surface between the boss portion (73) and the drive shaft (11). The oil supply passage (16) opens into the upper end surface of the drive shaft (11) and supplies lubricating oil to the upper portion of the drive shaft (11).

[0057] The recess (32) of the housing (30) communicates with the oil supply passage (16) of the drive shaft (11) through the inside of the boss portion (73) of the movable scroll (70). High-pressure lubricating oil is supplied to the recess (32), so that a high pressure corresponding to the discharge pressure of the compression mechanism (50) acts on the recess (32). The high pressure of the recess (32) presses the movable scroll (70) against the fixed scroll (60).

[0058] An oil passage (not shown) is formed inside the housing (30) and the fixed scroll (60). The oil passage supplies high-pressure lubricating oil in the recess (32) to the opposing surfaces of the movable end plate (71) of the movable scroll (70) and the outer circumferential wall (63) of the fixed scroll (60).

[0059] - Driving operation - The basic operation of the scroll compressor (10) will be described. In Fig. 2, when the motor (25) is operated, the drive shaft (11) to which the rotor (27) is fixed is rotated. The movable scroll (70) is prevented from rotating by the Oldham coupling (55), and therefore revolves around the axis of the drive shaft (11).

[0060] When the movable scroll (70) orbits, the refrigerant 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 discharge space (23) through a passage (not shown) formed in the housing (30). The high-pressure gas refrigerant in the discharge space (23) is discharged to the outside of the casing (20) through the discharge pipe (13).

[0061] As the drive shaft (11) rotates, the high-pressure lubricating oil in the oil reservoir (21) is sucked up by the pump (24), 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 movable scroll (70).

[0062] The lubricating oil supplied to the boss portion (73) flows out into the recessed portion (32) of the housing (30) through a gap between the eccentric portion (15) of the drive shaft (11) and the boss portion (73). As a result, the recessed portion (32) of the housing (30) becomes under high pressure corresponding to the discharge pressure of the compression mechanism (50). The high pressure in the recessed portion (32) presses the movable scroll (70) against the fixed scroll (60).

[0063] -Effects of the embodiment- According to the feature of this embodiment, by supporting the drive shaft (11) on both the compression mechanism (50) side and the motor (25) side of the balance weight (18), it is possible to prevent the drive shaft (11) from being deflected by the centrifugal force of the balance weight (18). This makes it possible to prevent the surface pressure of the drive shaft (11) from becoming locally high, thereby improving reliability and enabling the scroll compressor (10) to be operated at high speed.

[0064] According to the features of the present embodiment, the axial length of the portion of the drive shaft (11) supported by the first support portion (35) is set to be the same as or longer than the axial length of the portion of the drive shaft (11) supported by the second support portion (45). This increases the contact area between the first support portion (35) located closer to the compression mechanism (50) and the drive shaft (11), thereby making it possible to effectively suppress bending of the drive shaft (11) due to the centrifugal force of the balance weight (18).

[0065] According to the feature of the present embodiment, the drive shaft (11) is supported by the first bearing (37) and the second bearing (47), so that the drive shaft (11) can be smoothly rotated.

[0066] According to the features of the present embodiment, the first housing body (31) having the first support portion (35) and the second housing body (41) having the second support portion (45) are formed from separate members, thereby improving the ease of assembly. Furthermore, by combining the first housing body (31) and the second housing body (41), the balance weight (18) is surrounded by the first housing body (31) and the second housing body (41), so that the flow of the refrigerant in the casing (20) is prevented from being disturbed by the rotation of the balance weight (18).

[0067] According to the features of the present embodiment, it is possible to provide a refrigeration system (1) including a rotary compressor (10) and a refrigerant circuit (1a) through which a refrigerant compressed by the rotary compressor (10) flows.

[0068] <<Variation>> Hereinafter, the same parts as those in the above embodiment will be denoted by the same reference numerals, and only the differences will be described.

[0069] As shown in Fig. 4, the drive shaft (11) has a balance weight (18). The balance weight (18) is disposed between the compression mechanism (50) and the motor (25).

[0070] The balance weight 18 has a weight protrusion 19. The weight protrusion 19 is provided by a portion of the upper surface of the balance weight 18 protruding. The weight protrusion 19 extends along the outer periphery of the balance weight 18 and protrudes upward.

[0071] The housing (30) has a first housing body (31) and a second housing body (41). The balance weight (18) is accommodated in an accommodating recess (42) of the second housing body (41).

[0072] A ring groove (39) is provided on the bottom surface of the first housing body (31). The weight protrusion (19) is disposed to fit into the ring groove (39). The ring groove (39) has a groove width and a groove depth set so that the weight protrusion (19) does not interfere with the first housing body (31) when the balance weight (18) rotates.

[0073] In this manner, by providing the weight protrusions (19) along the outer peripheral edge of the balance weight (18), the overall weight of the balance weight (18) can be increased.

[0074] Although the embodiments and modifications have been described above, it will be understood that various modifications of form and details are possible without departing from the spirit and scope of the claims. In addition, the elements of the above embodiments, modifications, and other embodiments may be appropriately combined or substituted. In addition, the descriptions "first," "second," "third," etc. in the specification and claims are used to distinguish the words to which these descriptions are attached, and do not limit the number or order of the words. [Industrial Applicability]

[0075] INDUSTRIAL APPLICABILITY As described above, the present disclosure is useful for rotary compressors and refrigeration devices. [Explanation of symbols]

[0076] 1 Refrigeration equipment 1a Refrigerant circuit 10 Scroll compressor (rotary compressor) 11 Drive shaft 18 Balance weight 20 Casing 25 Motor 30 Housing (support member) 31 First housing body 35 1st support part 37 No. 1 bearing 41 Second housing body 45 Second support part 47 No. 2 bearing 50 Compression mechanism

Claims

1. A rotary compressor comprising: a compression mechanism (50) that compresses a refrigerant; a drive shaft (11) that drives the compression mechanism (50); and a motor (25) that rotates the drive shaft (11), a support member (30) disposed between the compression mechanism (50) and the motor (25) and configured to rotatably support the drive shaft (11); a lower bearing (22) that rotatably supports the drive shaft (11) below the motor (25); a balance weight (18) provided on the drive shaft (11) and disposed between the compression mechanism (50) and the motor (25), the support member (30) has a first support portion (35) that supports the drive shaft (11) on the compression mechanism (50) side relative to the balance weight (18), and a second support portion (45) that supports the drive shaft (11) on the motor (25) side relative to the balance weight (18), the support member (30) includes a first housing body (31) having the first support portion (35) and a second housing body (41) having the second support portion (45), The second housing body (41) is provided with an accommodating recess (42) by recessing a part of the second housing body (41), the second housing body (41) is fixed to the first housing body (31), The balance weight (18) is accommodated in the accommodation recess (42). Rotary compressor.

2. The rotary compressor according to claim 1, An axial length L1 of a portion of the drive shaft (11) supported by the first support portion (35) and an axial length L2 of a portion of the drive shaft (11) supported by the second support portion (45) satisfy the condition L1≧L2. Rotary compressor.

3. The rotary compressor according to claim 1 or 2, a first bearing (37) provided in the first support portion (35) and supporting the drive shaft (11); a second bearing (47) provided in the second support portion (45) and supporting the drive shaft (11); Rotary compressor.

4. The rotary compressor according to claim 1 or 2, a casing (20) that houses the compression mechanism (50), the support member (30) includes a first housing body (31) having the first support portion (35) and a second housing body (41) having the second support portion (45), The first housing body (31) is fixed to the casing (20), The second housing body (41) is fixed to the first housing body (31). Rotary compressor.

5. A rotary compressor (10) according to claim 1 or 2; a refrigerant circuit (1a) through which the refrigerant compressed by the rotary compressor (10) flows. Refrigeration equipment.

Images