Rotary compressor and refrigeration cycle device

Abstract

Reduces oil rise rate. The refrigerant is a single hydrocarbon refrigerant or a mixed refrigerant containing the hydrocarbon refrigerant. The displacement volume of the compression mechanism (40) is Vc [cc], and the density of the refrigerant at 1.9 MPa and 75°C is Dg [g / cm 3 ], the rotation speed of the rotating shaft (30) is N [rps], the volume of the primary space (S1) is V1 [cc], the volume of the secondary space (S2) is V2 [cc], the height of the primary space (S1) is H1 [cm], the height of the secondary space (S2) is H2 [cm], and the density of the refrigerating machine oil at 15°C is Do [g / cm 3 ], and the dissolved viscosity of the refrigeration oil present at a height below the suction port (71a) is defined as η [mPa·S]. The rotary compressor satisfies N≧100 [rps] and ((8.19×10 -8 ×Vc×Dg+0.000327)×Vc 3.657 ×N 3.126 ) / (V1×V2×H1 1.867 ×H2 1.556 × Do × η)≦1.0.

Description

[Technical Field]

[0001] The present disclosure relates to a rotary compressor and a refrigeration cycle apparatus. A rotary compressor compresses gas in a compression chamber formed in a cylinder by eccentrically rotating a roller within the cylinder. Rotary compressors generally have vanes to separate the compression chambers. Rotary compressors include a so-called swing type in which a vane formed integrally with the roller oscillates in response to the eccentric rotation of the roller, a so-called rolling piston type in which a vane separate from the roller rotates eccentrically while abutting against the roller, and a so-called hinge vane type in which a roller rotates eccentrically with the tip of the vane rotatably fitted in a recess on the outer circumferential surface of the roller. [Background technology]

[0002] Patent Document 1 discloses a refrigeration cycle device. The refrigeration cycle device has a refrigerant circuit. The refrigerant circuit has a rotary compressor, a radiator, an expansion valve, and an evaporator. When the rotary compressor is operated, refrigerant circulates in the refrigerant circuit, performing a refrigeration cycle.

[0003] In a rotary compressor, the refrigerant compressed in the compression mechanism flows through the space inside the casing and then flows out from the discharge pipe to the refrigerant circuit, filling the inside of the casing with high-pressure refrigerant.

[0004] An oil reservoir is formed at the bottom of the casing to store refrigeration oil. The refrigeration oil is used to lubricate the sliding parts of the rotary compressor. The refrigeration oil in the oil reservoir is drawn into the suction port of the oil supply pump and supplied to the sliding parts of the compression mechanism through an oil supply passage in the rotating shaft. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2023-162986 Summary of the Invention [Problem to be solved by the invention]

[0006] Hydrocarbon refrigerants, such as propane, are used in the refrigerant circuits of refrigeration cycle equipment. Hydrocarbon refrigerants are natural refrigerants with extremely low global warming potential. On the other hand, hydrocarbon refrigerants generally have a molecular structure similar to that of refrigerating machine oil, making them easily soluble in refrigerating machine oil. When a refrigerant dissolves in refrigerating machine oil, the dissolving viscosity of the refrigerating machine oil decreases, reducing the viscous resistance of the refrigerating machine oil. As a result, the refrigerating machine oil in the casing is more likely to flow out of the discharge pipe into the refrigerant circuit along with the refrigerant, potentially increasing the oil rise rate (the proportion of refrigerating machine oil contained in the fluid flowing out of the discharge pipe).

[0007] The objective of the present disclosure is to reduce the oil rise rate. [Means for solving the problem]

[0008] The first aspect relates to a rotary compressor, which includes an electric motor (25), a rotating shaft (30) connected to the electric motor (25), a compression mechanism (40) disposed below the electric motor (25) and driven by the rotating shaft (30) to compress a refrigerant, a casing (21) that houses the electric motor (25), the rotating shaft (30), and the compression mechanism (40) and is filled with high-pressure refrigerant discharged from the compression mechanism (40), and an oil supply mechanism (70) that has a suction port (71a) for drawing refrigeration oil accumulated at the bottom of the casing (21) and supplies the refrigeration oil to sliding parts. The compression mechanism (40) includes annular cylinders (51A, 51B), annular rollers (52A, 52B) that rotate eccentrically within the cylinders (51A, 51B), and vanes (53A, 53B) for forming compression chambers within the cylinders (51A, 51B). The internal space (S) of the casing (21) includes a primary space (S1) between the compression mechanism (40) and the electric motor (25), and a secondary space (S2) above the electric motor (25). A discharge pipe (24) that communicates with the secondary space (S2) is connected to the casing (21). The refrigerant is a single refrigerant made of a hydrocarbon refrigerant or a mixed refrigerant containing a hydrocarbon refrigerant. The displacement volume of the compression mechanism (40) is Vc [cc], and the density of the refrigerant at 1.9 MPa and 75°C is Dg [g / cm 3 ], the rotation speed of the rotating shaft (30) is N [rps], the volume of the primary space (S1) is V1 [cc], the volume of the secondary space (S2) is V2 [cc], the height of the primary space (S1) is H1 [cm], the height of the secondary space (S2) is H2 [cm], and the density of the refrigerating machine oil at 15°C is Do [g / cm 3 ], and the dissolved viscosity of the refrigerating machine oil present at or below the height of the suction port (71a) is defined as η [mPa·S]. The rotary compressor satisfies N≧100 [rps] and ((8.19×10 -8 ×Vc×Dg+0.000327)×Vc 3.657 ×N 3.126 ) / (V1×V2×H1 1.867 ×H2 1.556 × Do × η)≦1.0.

[0009] As a result of verification, it was confirmed that, even during operation at a rotation speed N of 100 [rps] or more, by satisfying the above relational expression, the oil rise rate α can be made 1.0% or less. Therefore, in the first aspect, during operation at a rotation speed N of the rotating shaft (30) of 100 or more, the oil rise rate α can be made 1.0% or less.

[0010] In the second embodiment, when the overall height of the casing (21) in the first embodiment is defined as Hc, H2 / Hc≦0.25.

[0011] In the second aspect, by setting H2 / Hc≦0.25, the volume of the secondary space (S2) becomes relatively small, and the amount of refrigerant retained in the secondary space (S2) can be reduced, thereby ensuring the amount of refrigerant used in the refrigeration cycle of the refrigerant circuit (10).

[0012] In the third embodiment, when the overall height of the casing (21) in the first or second embodiment is defined as H, 0.2≦H2 / Hc is satisfied.

[0013] In the third aspect, the height H2 of the secondary space (S2) can be prevented from becoming excessively small, and as a result, oil can be separated from the refrigerant in the secondary space (S2), thereby reducing the oil rising rate.

[0014] In a fourth aspect, in any one of the first to third aspects, the refrigerating machine oil contains any one of polyalkylene glycol, polyvinyl ether, or polyol ester.

[0015] In a fourth aspect, the refrigerating machine oil contains polyalkylene glycol, polyvinyl ether, or polyol ester. These refrigerating machine oils are relatively difficult to dissolve hydrocarbon refrigerants in. Therefore, it is possible to prevent an increase in the oil rise rate caused by the hydrocarbon refrigerant dissolving in the refrigerating machine oil.

[0016] A fifth aspect is any one of the first to fourth aspects, wherein the density of the refrigerant Do [g / cm 3 ] is 37 [g / cm 3] or more, 44[g / cm 3 ] is as follows.

[0017] In the fifth aspect, the density Do of the refrigerant is relatively small, so the amount of refrigerant circulating in the refrigeration cycle is small, and as a result, the oil rise rate can be reduced.

[0018] In a sixth aspect, in any one of the first to fifth aspects, the refrigerating machine oil contains at least one of a phosphate ester extreme pressure additive, an antioxidant, and an acid scavenger.

[0019] In a seventh aspect, in any one of the first to sixth aspects, the refrigerating machine oil contains 0.1 wt % or more and 0.5 wt % or less of an antioxidant or an acid scavenger.

[0020] In the seventh aspect, the antioxidant or acid scavenger is contained in an amount of 0.5% by weight or less relative to the weight of the refrigerating machine oil, so that the dissolution viscosity of the refrigerating machine oil can be prevented from being excessively reduced due to an increased content of the antioxidant or acid scavenger, and as a result, the oil rising rate can be reduced.

[0021] In an eighth aspect, in any one of the first to seventh aspects, the refrigerating machine oil contains 1.0 wt % or more and 5.0 wt % or less of an extreme pressure additive.

[0022] In the eighth aspect, the content of the extreme-pressure additive is 5.0% by weight or less relative to the weight of the refrigerating machine oil, so that it is possible to prevent the dissolution viscosity of the refrigerating machine oil from becoming excessively low due to an increase in the content of the extreme-pressure additive, and as a result, the oil rising rate can be reduced.

[0023] In a ninth aspect, in any one of the first to eighth aspects, the molecular weight of the refrigerating machine oil is 1,000 or more and 1,800 or less.

[0024] In the ninth aspect, by setting the molecular weight of the refrigerating machine oil to be equal to or greater than 1000 and equal to or less than 1800, it is possible to suppress dissolution of the hydrocarbon refrigerant into the refrigerating machine oil, and as a result, it is possible to reduce the oil rising rate.

[0025] A tenth aspect is directed to a refrigeration cycle apparatus. The refrigeration cycle apparatus includes a refrigerant circuit (10) having any one of the first to ninth compressors (20) and in which a hydrocarbon refrigerant circulates to perform a refrigeration cycle. [Brief explanation of the drawings]

[0026] [Figure 1] FIG. 1 is a piping diagram of a refrigeration cycle device. [Figure 2] FIG. 2 is a vertical cross-sectional view of the compressor. [Figure 3] FIG. 3 is an enlarged longitudinal sectional view of a main part of the compressor. [Figure 4] FIG. 4 is a cross-sectional view of the first compression element. [Figure 5] FIG. 5 is a cross-sectional view of the second compression element. [Figure 6] FIG. 6 is an enlarged longitudinal sectional view of a portion of the compressor for explaining the primary space and the secondary space. DETAILED DESCRIPTION OF THE INVENTION

[0027] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. 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.

[0028] (1) Overall configuration of the refrigeration cycle device The refrigeration cycle device of the present disclosure is applied to a stationary air conditioner 1. As shown in Fig. 1, the air conditioner 1 is a pair type having one outdoor unit (OU) installed outdoors and one indoor unit (IU) installed indoors. The outdoor unit (OU) and the indoor unit (IU) are connected to each other via two connecting pipes.

[0029] The air conditioner (1) has a refrigerant circuit (10). The refrigerant circuit (10) is filled with a refrigerant. The refrigerant circuit (10) performs a refrigeration cycle by circulating the refrigerant. The refrigerant circuit (10) has a compressor (20), an outdoor heat exchanger (11), an expansion valve (12), and an indoor heat exchanger (13). The refrigerant circuit (10) further has a four-way switching valve (14) for switching between a cooling cycle and a heating cycle. The compressor (20), the outdoor heat exchanger (11), and the expansion valve (12) are provided in the outdoor unit (OU), and the indoor heat exchanger (13) is provided in the indoor unit (IU). The expansion valve (12) may be provided in the indoor unit (IU).

[0030] The compressor (20) draws in and compresses low-pressure refrigerant from the refrigerant circuit (10). The compressor (20) discharges the compressed refrigerant into the refrigerant circuit (10) as high-pressure refrigerant. The outdoor heat exchanger (11) is a fin-and-tube heat exchanger. The outdoor heat exchanger exchanges heat between the refrigerant in the refrigerant circuit (10) and outdoor air transported by the outdoor fan (15). The expansion valve (12) is an example of a pressure reducing mechanism that reduces the pressure of the refrigerant. The expansion valve (12) is an electronic expansion valve whose opening is adjustable. The indoor heat exchanger (13) is a fin-and-tube heat exchanger. The indoor heat exchanger exchanges heat between the refrigerant in the refrigerant circuit (10) and outdoor air transported by the indoor fan (16).

[0031] The four-way selector valve (14) has a first port (P1), a second port (P2), a third port (P3), and a fourth port (P4). The four-way selector valve (14) switches between a first state indicated by a solid line in FIG. 1 and a second state indicated by a dashed line in FIG. 1. In the first state, the four-way selector valve (14) connects the first port (P1) with the second port (P2) and also connects the third port (P3) with the fourth port (P4). When the four-way selector valve (14) is in the first state, the compressor (20) operates, whereby the outdoor heat exchanger (11) functions as a radiator (condenser) and the indoor heat exchanger (13) functions as an evaporator, thereby performing a cooling cycle. The four-way selector valve (14) in the second state connects the first port (P1) and the third port (P3) and also connects the second port (P2) and the fourth port (P4). When the four-way selector valve (14) is in the second state, the compressor (20) is operated, whereby a heating cycle is performed in which the indoor heat exchanger (13) functions as a radiator (condenser) and the outdoor heat exchanger (11) functions as an evaporator.

[0032] (2) Compressor The configuration of the compressor (20) will be described with reference to Figs. 2 to 6. In the following description, the terms "upper" and "lower" refer to the directions indicated by the arrows in Fig. 2. In the following description, the term "axial direction" refers to the direction in which the axis (A) of the rotating shaft (30) shown in Fig. 2 extends, the term "radial direction" refers to the direction passing through the axis (A) of the rotating shaft (30) and perpendicular to the axis (A), and the term "circumferential direction" refers to the direction in which the rotating shaft (30) rotates.

[0033] The compressor (20) is a rotary compressor. The rotary compressor of this embodiment is a so-called swing type in which vanes (53A, 53B) formed integrally with rollers (52A, 52B) swing in association with the eccentric rotation of the rollers (52A, 52B).

[0034] The compressor (20) has a casing (21) and a plurality of components housed in the casing (21). The plurality of components include an electric motor (25), a rotating shaft (30), a compression mechanism (40), and an oil supply mechanism (70). The electric motor (25) is a drive source for the compression mechanism (40). The rotating shaft (30) is connected to the electric motor (25). The bearings (44, 45) rotatably support the rotating shaft (30). The compression mechanism (40) is rotationally driven by the rotating shaft (30) to compress the refrigerant. The oil supply mechanism (70) supplies refrigeration oil, which is a lubricant, to a plurality of sliding parts.

[0035] (2-1) Casing The casing (21) is a hollow, sealed container. An internal space (S) is formed inside the casing (21). The casing (21) is formed to be elongated in the axial direction, specifically, in the vertical direction. The casing (21) has a cylindrical body (21a) extending in the vertical direction, an upper lid (21b) closing the upper end of the body (21a), and a lower lid (21c) closing the lower end of the body (21a). The lower lid (21c) forms the bottom of the casing (21).

[0036] The internal space (S) of the casing (21) is filled with refrigerant discharged from the compression mechanism (40). That is, the compressor (20) is of a so-called high-pressure dome type. The internal space (S) of the casing (21) includes a primary space (S1) between the compression mechanism (40) and the electric motor (25) and a secondary space (S2) above the electric motor (25).

[0037] An oil reservoir (35) for storing refrigeration oil is formed at the bottom of the casing (21). In the oil reservoir (35), the oil level of the refrigeration oil changes depending on the operating conditions of the compressor (20) and the air conditioner (1).

[0038] (2-2) First intake pipe, second intake pipe, and discharge pipe A first suction pipe (23A), a second suction pipe (23B), and a discharge pipe (24) are connected to the casing (21). The first suction pipe (23A) and the second suction pipe (23B) extend radially through the body portion (21a). The first suction pipe (23A) and the second suction pipe (23B) are connected to a low-pressure line of the refrigerant circuit (10). The discharge pipe (24) extends axially through the upper lid portion (21b). The discharge pipe (24) is connected to a high-pressure line of the refrigerant circuit (10).

[0039] (2-3) Electric motor The electric motor (25) is located in the upper part of the internal space (S). The electric motor (25) has a stator (26) and a rotor (27). The stator (26) is fixed to the inner peripheral surface of the body portion (21a). The stator (26) is formed in a cylindrical shape when viewed in a cross section perpendicular to the axial direction (horizontal cross section). The rotor (27) is disposed radially inside the stator (26). The rotor (27) is fixed to the outer peripheral surface of the rotating shaft (30). The electric motor (25) is configured so that its rotation speed can be adjusted by an inverter device. In other words, the electric motor (25) is an inverter-type electric motor whose operating frequency is variable.

[0040] (2-4) Rotation axis The rotating shaft (30) is located at the radial center of the internal space (S). The rotating shaft (30) extends vertically. The rotating shaft (30) has a shaft body (31) and a first eccentric portion (32A) and a second eccentric portion (32B), each of which is radially eccentric from an axial center (A) of the shaft body (31). The rotor (27) of the electric motor (25) is connected to an upper portion of the shaft body (31). The first eccentric portion (32A) and the second eccentric portion (32B) are formed in a lower portion of the shaft body (31). The first eccentric portion (32A) is located above the second eccentric portion (32B). The direction in which the first eccentric portion (32A) is eccentric from the axial center (A) and the direction in which the second eccentric portion (32B) is eccentric from the axial center are circumferentially offset by 180° from each other.

[0041] (2-5) Overall configuration of the compression mechanism The compression mechanism (40) is disposed below the electric motor (25). The compression mechanism (40) includes, in order from top to bottom, a front head (41), a first cylinder (51A), a middle plate (42), a second cylinder (51B), and a rear head (43). These members are fixed to each other by bolts extending in the axial direction.

[0042] The compression mechanism (40) of this embodiment includes a first compression element (C1) and a second compression element (C2). The first compression element (C1) includes a first roller (52A) and a first vane (53A). The second compression element (C2) includes a second roller (52B) and a second vane (53B). In the compression mechanism (40) of this embodiment, the rollers (52A, 52B) and the vanes (53A, 53B) are integrally formed, and the vanes (53A, 53B) swing in accordance with the eccentric rotation of the rollers (52A, 52B).

[0043] A first cylinder chamber (54A) is formed inside the first cylinder (51A). The first cylinder chamber (54A) passes through the first cylinder (51A) in the axial direction. A second cylinder chamber (54B) is formed inside the second cylinder (51B). The second cylinder chamber (54B) passes through the second cylinder (51B) in the axial direction.

[0044] (2-5-1) Closure member The front head (41), the middle plate (42), and the rear head (43) are examples of closing members that close the cylinder chambers (54A, 54B) in the axial direction. The front head (41) has a first closing portion (41a) that is a flat plate and has a slight thickness in the axial direction, and an upper bearing portion (41b) that extends upward from the radial center of the first closing portion (41a).

[0045] The lower surface of the first closing portion (41a) closes the upper opening of the first cylinder chamber (54A). As shown in Fig. 4, the first closing portion (41a) is formed with a first discharge port (55A) that communicates with the high-pressure chamber (compression chamber) of the first cylinder chamber (54A). The first discharge port (55A) is opened and closed by a first discharge valve (not shown).

[0046] The upper bearing portion (41b) is formed in a cylindrical shape extending in the axial direction along the rotating shaft (30). The rotating shaft (30) passes through the upper bearing portion (41b). A first bearing (44) is formed on the inner peripheral surface of the upper bearing portion (41b). The first bearing (44) rotatably supports the main shaft portion of the rotating shaft (30). The first bearing (44) is a sliding bearing, specifically a journal bearing.

[0047] The middle plate (42) is disposed between the first cylinder (51A) and the second cylinder (51B). The middle plate (42) is formed in an annular shape. The rotary shaft (30) passes through the middle plate (42). The upper surface of the middle plate (42) closes the lower opening of the first cylinder chamber (54A). The lower surface of the middle plate (42) closes the upper opening of the second cylinder chamber (54B).

[0048] The rear head (43) has a second closing portion (43a) that is a flat plate and slightly thick in the axial direction, and a lower bearing portion (43b) that extends downward from the radial center of the second closing portion (43a). The upper surface of the second closing portion (43a) closes the lower opening of the second cylinder chamber (54B). As shown in FIG. 5, the second closing portion (43a) has a second discharge port (55B) that communicates with the high-pressure chamber (compression chamber) of the second cylinder chamber (54B). The second discharge port (55B) is opened and closed by a second discharge valve (not shown).

[0049] The lower bearing portion (43b) is formed in a cylindrical shape extending in the axial direction along the rotating shaft (30). The rotating shaft (30) passes through the lower bearing portion (43b). A second bearing (45) is formed on the inner peripheral surface of the lower bearing portion (43b). The second bearing (45) rotatably supports the countershaft portion of the rotating shaft (30). The second bearing (45) is a sliding bearing, specifically a journal bearing.

[0050] (2-5-2) Details of the first compression element The first compression element (C1) shown in FIG. 4 includes a first eccentric part (32A), a first cylinder (51A), a first roller (52A), a first vane (53A), and a pair of first bushings (56A).

[0051] The first cylinder (51A) is an annular member having a slight thickness in the axial direction. A first cylinder chamber (54A) is formed inside the first cylinder (51A). The first cylinder chamber (54A) is formed in a circular shape when viewed in the axial direction. A first suction passage (57A) and a first bushing groove (58A) are formed in the first cylinder (51A). The first suction passage (57A) passes through the first cylinder (51A) in the radial direction. The first suction passage (57A) communicates with the first suction pipe (23A).

[0052] The first roller (52A) is disposed in the first cylinder chamber (54A). The first roller (52A) is formed in an annular shape when viewed in the axial direction. The first eccentric portion (32A) is fitted inside the first roller (52A). The inner peripheral surface of the first roller (52A) and the outer peripheral surface of the first eccentric portion (32A) slide relative to each other. The first eccentric portion (32A) causes the first roller (52A) to eccentrically rotate. The first roller (52A) eccentrically rotates along the inner peripheral surface of the first cylinder chamber (54A) while forming a seal between itself and the inner peripheral surface of the first cylinder chamber (54A).

[0053] The first bushing groove (58A) is formed on the top dead center side (upper side in FIG. 3 ) of the first cylinder (51A). The first bushing groove (58A) is formed in a circular shape when viewed in the axial direction. The pair of first bushings (56A) are fitted into the first bushing groove (58A). Each of the pair of first bushings (56A) has an arc portion shaped along the inner surface of the first bushing groove (58A) and flat portions continuous with both ends of the arc portion. The pair of first bushings (56A) are arranged in the first bushing groove (58A) such that the flat portions face each other. The flat portions of the pair of first bushings (56A) hold the first vane (53A). The pair of first bushings (56A) are configured to be swingable along the inner surface of the first bushing groove (58A). The first vane (53A) is configured to be able to move reciprocally in the radial direction between the pair of first bushings (56A).

[0054] The first vane (53A) constitutes a partition member that divides the first cylinder chamber (54A) into a low-pressure chamber (L) and a high-pressure chamber (H). A radially inner portion of the first vane (53A) is continuous with the outer peripheral surface of the first roller (52A). The low-pressure chamber (L) of the first cylinder chamber (54A) communicates with the first suction passage (57A) and constitutes a suction chamber into which low-pressure refrigerant flows. The high-pressure chamber (H) of the first cylinder chamber (54A) is isolated from the first suction passage (57A) and constitutes a compression chamber for compressing the refrigerant.

[0055] (2-5-3) Details of the second compression element The second compression element (C2) shown in Fig. 5 includes a second eccentric portion (32B), a second cylinder (51B), a second roller (52B), a second vane (53B), and a pair of second bushings (56B). The basic structures of the second eccentric portion (32B), the second cylinder (51B), the second roller (52B), the second vane (53B), and the pair of second bushings (56B) are the same as those of the first eccentric portion (32A), the first cylinder (51A), the first roller (52A), the first vane (53A), and the pair of first bushings (56A), respectively, and therefore detailed description thereof will be omitted. The second cylinder (51B) is formed with a second cylinder chamber (54B), a second suction passage (57B), and a second bushing groove (58B). The second cylinder chamber (54B), the second suction passage (57B), and the second bush groove (58B) have the same basic structures as the first cylinder chamber (54A), the first suction passage (57A), and the first bush groove (58A), respectively, and therefore detailed description thereof will be omitted. The second suction passage (57B) is in communication with the second suction pipe (23B). The first roller (52A) and the second roller (52B) are out of phase with each other by 180° during eccentric rotation.

[0056] (2-6) Oil supply mechanism The oil supply mechanism (70) shown in Fig. 3 supplies refrigeration oil from the oil reservoir (35) to a plurality of sliding parts. The oil supply mechanism (70) is provided below the rotating shaft (30). The oil supply mechanism (70) includes an oil supply pump (71) and an oil supply passage (72).

[0057] The oil supply pump (71) is provided at the lower end of the rotary shaft (30). The oil supply pump (71) is located at a position lower than the oil level in the oil reservoir (35). The oil supply pump (71) transports refrigeration oil from the oil reservoir (35). The oil supply pump (71) has a suction port (71a) that draws the refrigeration oil from the oil reservoir (35). The suction port (71a) opens downward toward the bottom of the casing (21). The oil supply pump (71) is a differential pressure type, centrifugal type, or positive displacement type pump.

[0058] The oil supply passage (72) is formed inside the rotary shaft (30). The oil supply passage (72) is in communication with the discharge side of the oil supply pump (71). The oil supply passage (72) has a main flow path (73) extending vertically so as to pass through the axis of the rotary shaft (30) and a plurality of branch flow paths extending radially from the main flow path (73). The plurality of branch flow paths include, in order from top to bottom, a first branch flow path (74a), a second branch flow path (74b), a third branch flow path (74c), and a fourth branch flow path (74d).

[0059] The first branch channel (74a) is located at the same height as the upper bearing portion (41b). An outlet of the first branch channel (74a) opens toward the first bearing (44). In other words, the first branch channel (74a) opens toward the sliding portion between the first bearing (44) and the rotary shaft (30). The second branch channel (74b) is formed in the first eccentric portion (32A). An outlet of the second branch channel (74b) opens toward the inner circumferential surface of the first roller (52A). In other words, the second branch channel (74b) opens toward the sliding portion between the first roller (52A) and the first eccentric portion (32A). The third branch channel (74c) is formed in the second eccentric portion (32B). An outlet of the third branch channel (74c) opens toward the inner circumferential surface of the first roller (52A). In other words, the third branch channel (74c) opens toward the sliding portion between the second roller (52B) and the second eccentric portion (32B). The fourth branch channel (74d) is located at the same height as the lower bearing portion (43b). The outlet of the fourth branch channel (74d) opens toward the second bearing (45). In other words, the fourth branch channel (74d) opens toward the sliding portion between the second bearing (45) and the rotating shaft (30).

[0060] (2-7) Driving behavior When the rotary shaft (30) is driven to rotate by the electric motor (25), the first eccentric portion (32A) and the second eccentric portion (32B) rotate eccentrically. In the first compression element (C1), low-pressure refrigerant is sucked from the first suction pipe (23A) into the low-pressure chamber (L) of the first cylinder chamber (54A) in accordance with the eccentric rotation of the first roller (52A). At the same time, the refrigerant is compressed in the high-pressure chamber (H) of the first cylinder chamber (54A). In the second compression element (C2), low-pressure refrigerant is sucked from the second suction pipe (23B) into the low-pressure chamber (L) of the first cylinder chamber (54A) in accordance with the eccentric rotation of the second roller (52B). At the same time, the refrigerant is compressed in the high-pressure chamber of the second cylinder chamber (54B).

[0061] When the internal pressure of the compression chamber of the first compression element (C1) increases and the first reed valve opens, high-pressure refrigerant is discharged into the internal space (S) through the first discharge port (55A). When the internal pressure of the compression chamber of the second compression element (C2) increases and the second reed valve opens, high-pressure refrigerant is discharged into the internal space (S) through the second discharge port (55B). The high-pressure refrigerant around the compression mechanism (40) passes upward through the electric motor (25) and is discharged into the refrigerant circuit (10) through the discharge pipe (24).

[0062] When the rotating shaft (30) rotates, the oil supply pump (71) rotates together with the rotating shaft (30). As a result, refrigeration oil in the oil reservoir (35) is sucked into the suction port (71a). The oil supply pump (71) delivers the refrigeration oil sucked through the suction port (71a) to the branch flow paths (74a, 74b, 74c, 74d) through the main flow path (73). The refrigeration oil in the first branch flow path (74a) is used to lubricate the sliding parts of the first bearing (44), the refrigeration oil in the second branch flow path (74b) is used to lubricate the sliding parts of the first eccentric portion (32A), the refrigeration oil in the third branch flow path (74c) is used to lubricate the sliding parts of the second eccentric portion (32B), and the refrigeration oil in the fourth branch flow path (74d) is used to lubricate the sliding parts of the second bearing (45).

[0063] (3) Refrigerant The refrigerant in this embodiment is a hydrocarbon refrigerant. The hydrocarbon refrigerant in this embodiment is a single refrigerant made of propane (R290). Propane has an extremely low global warming potential and is environmentally friendly. On the other hand, hydrocarbon refrigerants such as propane have a molecular structure similar to that of refrigerating machine oil, and therefore have the property of easily dissolving in refrigerating machine oil.

[0064] The hydrocarbon refrigerant may be a single refrigerant consisting of isobutane. The refrigerant in the refrigerant circuit (10) may be a mixed refrigerant containing a hydrocarbon refrigerant and at least one other refrigerant. Examples of other refrigerants that may be used include HFC (hydrofluorocarbon) refrigerants, HFO (hydrofluoroolefin) refrigerants, and CF3I (trifluoroiodomethane).

[0065] (4) Refrigerating machine oil Next, a description will be given of the refrigerating machine oil used in the refrigerant circuit 10. The refrigerating machine oil here refers to a fluid containing additives such as an extreme-pressure additive, an antioxidant, and an acid scavenger in addition to components (lubricating oil) used to lubricate sliding parts.

[0066] The refrigerating machine oil used in the refrigerant circuit (10) of the present embodiment contains any one of PAG (polyalkylene glycol), PVE (polyvinyl ether), and POE (polyol ester). The refrigerating machine oil mainly contains PAG, PVE, or POE.

[0067] Hydrocarbon refrigerants such as propane have a molecular structure similar to that of refrigerating machine oil, making them easily soluble in refrigerating machine oil. In contrast, PAG, PVE, or POE have relatively low compatibility with hydrocarbon refrigerants. Therefore, using PAG, PVE, or POE as the refrigerating machine oil can prevent the refrigerant from dissolving in the refrigerating machine oil. Refrigerating machine oil can also be alkylbenzene or mineral oil.

[0068] Refrigeration oil has the property of separating into two layers when the refrigerant pressure is 1.9 MPa and the temperature of the refrigeration oil is 75° C. Therefore, the refrigeration oil in the oil reservoir (35) separates into two layers when the refrigerant pressure in the casing (21) is 1.9 MPa and the temperature of the refrigeration oil is 75° C.

[0069] Generally, refrigeration oil dissolves uniformly in refrigerant. However, if refrigeration oil with low solubility in refrigerant is used, a concentration gradient between the refrigeration oil and the refrigerant occurs in the oil reservoir (35), resulting in the refrigeration oil being in a so-called two-layer separation state. The refrigeration oil near the oil surface in the oil reservoir (35) has a low refrigerant density and therefore forms a layer with high refrigerant solubility. The refrigeration oil near the bottom of the oil reservoir (35) has a high refrigerant density and therefore forms a layer with low refrigerant solubility. The solution viscosity of the refrigeration oil changes depending on the refrigerant solubility. Therefore, by suppressing the refrigerant solubility, the solution viscosity of the refrigeration oil can be ensured. When the refrigerant and refrigeration oil are mixed, the refrigerant and refrigeration oil are not mixed and are separated into two layers, or an emulsion state is called a two-layer separation state.

[0070] The molecular weight of the refrigerating machine oil is preferably 1,000 or more and 1,800 or less.

[0071] The refrigerating machine oil contains at least one additive selected from the group consisting of a phosphate ester extreme pressure additive, an antioxidant, and an acid scavenger.

[0072] As the phosphate extreme pressure additive, those containing phosphate ester, phosphite ester, acid phosphate ester, acid phosphite ester, and amine salt of acid phosphite ester can be used.

[0073] The acid scavenger may be an epoxy compound such as phenyl glycidyl ether, alkyl glycidyl ether, alkylene glycol glycidyl ether, cyclohexene oxide, α-olefin oxide, or epoxidized soybean oil.

[0074] As the antioxidant, a phenol-based antioxidant or an amine-based antioxidant can be used.

[0075] The refrigerating machine oil contains 1.0 wt % or more and 5.0 wt % or less of an extreme pressure additive. The refrigerating machine oil contains 0.1 wt % or more and 0.5 wt % or less of an antioxidant or an acid scavenger.

[0076] The refrigerating machine oil of this embodiment has a surface tension of 0.25 [N / m] or more and 0.40 [N / m] or less at 20° C. The surface tension of the refrigerating machine oil is measured by a method in accordance with JIS K2241.

[0077] (5) Compressor parameters (5-1) Issues Hydrocarbon refrigerants such as propane have a molecular structure similar to that of refrigerating machine oil and therefore tend to dissolve easily in refrigerating machine oil. When the refrigerant dissolves in the refrigerating machine oil, the dissolution viscosity of the refrigerating machine oil decreases, and the viscous resistance of the refrigerating machine oil decreases. As a result, the refrigerating machine oil in the casing (21) tends to flow out of the casing (21) together with the refrigerant through the discharge pipe (24) into the refrigerant circuit (10), which may increase the oil leakage rate.

[0078] In addition, because hydrocarbon refrigerants are highly flammable, the amount of refrigerant charged into the refrigerant circuit (10) may be limited due to the risk of refrigerant leakage. However, because hydrocarbon refrigerants are easily soluble in refrigeration oil, a large amount of refrigerant is retained together with the refrigeration oil in the internal space (S) of the compressor (20). This creates a problem of a shortage of refrigerant used in the refrigeration cycle of the refrigerant circuit (10). In particular, in a separate-type air conditioner (1) in which the indoor unit (IU) and the outdoor unit (OU) are separated, the length of refrigerant piping is relatively long, and therefore, the problem of a shortage of refrigerant is particularly pronounced.

[0079] (5-2) Overview of the relational equation To solve this problem, the compressor (20) of this embodiment is configured to satisfy the following parameter relationships.

[0080] The displacement volume of the compression mechanism (40) is Vc [cc], and the density of the refrigerant at 1.9 MPa and 75°C is Dg [g / cm3 ], the rotation speed of the rotating shaft (30) is N [rps], the volume of the primary space (S1) is V1 [cc], the volume of the secondary space (S2) is V2 [cc], the height of the primary space (S1) is H1 [cm], the height of the secondary space (S2) is H2 [cm], the total height of the casing (21) is Hc [cm], and the density of the refrigerating machine oil at 15°C is Do [g / cm 3 ], the dissolved viscosity of the refrigeration oil present at a height position h1 or lower of the suction port (71a) is defined as η [mPa·S], and the oil rising rate of the rotary compressor is defined as α (wt %).

[0081] The compressor (20) of the present embodiment satisfies the following formulas (1), (2), (3), and (4).

[0082] N≧100...Equation (1) ((8.19×10 -8 ×Vc×Dg+0.000327)×Vc 3.657 ×N 3.126 ) / (V1×V2×H1 1.867 ×H2 1.556 ×Do×η)≦α, (α=1.0)···(2) formula H2 / Hc≦0.25···(3) formula 0.2≦H2 / Hc···(4) formula (5-3) Explanation of each parameter The oil rise rate α is the ratio of the weight Wo of refrigeration oil to the total weight Wt of the fluid flowing out from the discharge pipe (24), expressed as a percentage (α=Wo / Wt×100).

[0083] As the rotation speed N of the rotating shaft (30) increases, the amount of refrigerant circulating in the refrigerant circuit (10) increases, and the refrigeration oil tends to flow out of the casing (21) together with the refrigerant. Therefore, as the rotation speed N increases, the oil rise rate α also increases. In this embodiment, the rotation speed N is 100 rps or more, which is a relatively high speed, and therefore the oil rise rate tends to increase.

[0084] The displacement volume Vc is the volume of the high-pressure chamber (compression chamber) when the low-pressure chamber (L) is completely closed in the cylinder (51A, 51B) to form the high-pressure chamber (compression chamber), and corresponds to the maximum volume of the compression chamber. The compression mechanism (40) of this embodiment is a two-cylinder type. In this case, Vc defined here is the sum of the displacement volume Vc-1 of the first cylinder (51A) and the displacement volume Vc-2 of the second cylinder (51B). If the number of cylinders is n and the displacement volumes of the cylinders are Vc-n, Vc-n+1, ​​..., the displacement volume Vc is the sum of these displacement volumes Vc-n, Vc-n+1, ​​....

[0085] When the displacement volume Vc increases, the amount of refrigerant circulating in the refrigerant circuit (10) increases, and the refrigeration oil tends to flow out of the casing (21) together with the refrigerant. Therefore, when the displacement volume Vc increases, the oil rise rate α increases.

[0086] As the rotation speed N of the rotating shaft (30) increases, the amount of refrigerant circulating in the refrigerant circuit (10) increases, and refrigeration oil is more likely to flow out of the casing (21) together with the refrigerant. Therefore, as the rotation speed N increases, the oil rise rate α increases. The rotation speed N is preferably 120 rps or more, and more preferably 150 rps or more. The rotation speed N may be equal to or greater than the maximum rotation speed Nmax of the compressor (20). Here, the maximum rotation speed Nmax is a predetermined value equal to or greater than 100 rps, preferably equal to or greater than 120 rps, and more preferably equal to or greater than 150 rps.

[0087] As shown in FIG. 6 , the primary space (S1) is a space between the compression mechanism (40) and the electric motor (25). Strictly speaking, the primary space (S1) is a space between an upper end surface of the first closing portion (41a) of the front head (41) and lower ends of the stator (26) and the rotor (27) of the electric motor (25). The upper end surface of the first closing portion (40a) is a flat surface located above the recess in which the first reed valve is disposed. The volume V1 of the primary space (S1) corresponds to the volume of this space. However, as indicated by the dashed-line frame L1 in FIG. 6 , the volume V1 of the primary space (S1) is calculated while ignoring the presence of the upper bearing portion (41b) and the rotating shaft (30). As the volume V1 increases, the refrigerant and oil are more likely to separate in the primary space (S1), and the oil rise rate α decreases.

[0088] H1 is the height of the primary space (S1). Strictly speaking, H1 is the maximum height between the upper end surface of the first closing portion (41a) of the front head (41) and the lower ends of the stator (26) and the rotor (27), as shown in Fig. 6. When the height H1 of the primary space (S1) increases, the refrigerant and oil are more likely to separate in the primary space (S1), and the oil rise rate α decreases.

[0089] As shown in Fig. 6, the secondary space (S2) is the space above the electric motor (25). Strictly speaking, the secondary space (S2) is the space between the upper ends of the stator (26) and the rotor (27) of the electric motor (25) and the top (upper cover portion (21b)) of the casing (21). The volume V2 of the secondary space (S2) corresponds to the volume of this space. However, as shown by the dashed-line frame L2 in Fig. 6, the volume V2 of the secondary space (S2) is calculated while ignoring the presence of the rotating shaft (30) and the discharge pipe (24). When the volume V2 increases, the refrigerant and oil are more likely to separate in the secondary space (S2), and the oil rise rate α decreases.

[0090] H2 is the height of the secondary space (S2). Strictly speaking, H2 is the maximum height between the upper ends of the stator (26) and the rotor (27) of the electric motor (25) and the top (upper cover portion (21b)), as shown in Fig. 6. When the height H2 of the secondary space (S2) increases, the refrigerant and oil are more likely to separate in the secondary space (S2), and the oil rise rate α decreases.

[0091] 2, the height Hc is the overall height of the casing (21). In other words, the height Hc is the maximum height from the bottom end to the top end of the casing (21).

[0092] As the density Dg of the refrigerant increases, the amount of refrigerant circulating in the refrigerant circuit (10) increases, and the refrigeration oil tends to flow out of the casing (21) together with the refrigerant. Therefore, as the density Dg of the refrigerant decreases, the oil rise rate α decreases.

[0093] In this embodiment, the density Dg of the refrigerant is 37 [g / cm 3 ] or more, 44[g / cm 3 The density Dg of the refrigerant is smaller than the density of, for example, an HFC refrigerant. By reducing the density Dg of the refrigerant in this way, the oil rise rate α can be reduced.

[0094] The density Do of the refrigerating machine oil is the density of the refrigerating machine oil. When the density of the refrigerating machine oil increases, the refrigerating machine oil becomes less likely to flow out of the casing (21), and the oil rising rate α decreases.

[0095] The melt viscosity η of the refrigeration oil is the melt viscosity of the refrigeration oil (hereinafter also referred to as first refrigeration oil) present in the oil reservoir (35) at a height position h1 or lower of the suction port (71a) of the oil supply pump (71). The height position h1 of the suction port (71a) refers to the absolute height of a horizontal plane passing through the suction port (71a), as shown in FIG. 3. The "melt viscosity" refers to the viscosity of a fluid in which a refrigerant is dissolved in the refrigeration oil. The viscosity of this fluid is measured by a method conforming to JIS K2283. The melt viscosity of the refrigeration oil varies depending on the content of the extreme-pressure additive, antioxidant, or oxygen scavenger.

[0096] When the melt viscosity η decreases, the viscous resistance of the refrigeration oil decreases, and the refrigeration oil therefore flows out more easily from the casing (21). Therefore, by increasing the melt viscosity η, the oil rising rate α decreases.

[0097] The melt viscosity η is preferably 5.0 or more. If the melt viscosity η is less than 5.0, the amount of wear at the sliding portions of the bearings (44, 45) and the eccentric portions (32A, 32B) increases rapidly. In addition, by increasing the melt viscosity η in this manner, the oil rising rate α can be reduced.

[0098] The melt viscosity η is preferably 1.2 or less. If the melt viscosity η is too high, the sliding loss of the eccentric portions (32A, 32B) increases, and the efficiency of the compressor (20) decreases. If the melt viscosity is 1.2 or less, the decrease in the efficiency of the compressor (20) can be suppressed.

[0099] As described above, each of the above parameters affects the oil rise rate α. As a result of verification, the inventors of the present application have confirmed that the oil rise rate α can be expressed by equation (2). Therefore, by satisfying equations (1) and (2) (α=1.0), the oil rise rate α can be kept at 1.0 or less even when the rotation speed N of the compressor (20) is operated at 100 rps or more.

[0100] In this embodiment, as shown in formula (3), H2 / Hc≦0.25. If the height of the secondary space (S2) is excessively large relative to the overall length of the casing (21), the volume of the secondary space (S2) increases. As described above, hydrocarbon refrigerants are easily soluble in refrigeration oil, and therefore the amount of refrigerant held in the secondary space (S2) is particularly likely to increase as the volume of the secondary space (S2) increases. In contrast, by satisfying H2 / Hc≦0.25, the volume of the secondary space (S2) decreases. As a result, the amount of refrigerant held in the secondary space (S2) can be reduced. Therefore, even if the charge amount of the refrigerant circuit (10) is limited, the amount of refrigerant used in the refrigeration cycle can be secured. In other words, a normal refrigeration cycle can be performed, and the charge amount of the refrigerant circuit (10) can be reduced.

[0101] In this embodiment, as shown in formula (4), 0.2≦H2 / Hc is satisfied. If the height H2 of the secondary space (S2) is too low, the oil separation rate in the secondary space (S2) decreases, and the oil rise rate α increases. In contrast, by satisfying 0.2≦H2 / Hc, the function of separating refrigerating machine oil in the secondary space (S2) can be ensured, and the oil rise rate α can be reduced.

[0102] (6) Effects of the embodiment (6-1) The refrigerant in this embodiment is a hydrocarbon refrigerant. The rotary compressor has a speed of N≧100 [rps] and ((8.19×10 -8 ×Vc×Dg+0.000327)×Vc 3.657 ×N 3.126 ) / (V1×V2×H1 1.867 ×H2 1.556 × Do × η)≦α, (α=1.0).

[0103] With this configuration, when the compressor (20) is operated at a rotation speed N of 100 rps or more, the oil separation ratio α can be kept at 1.0 or less. This can prevent the supply of refrigeration oil to the bearings (44, 45) and the eccentric parts (32A, 32B) from becoming insufficient, thereby improving the reliability of the compressor (20).

[0104] (6-2) The compressor (20) of this embodiment satisfies the relational expression H2 / Hc≦0.25. This reduces the amount of refrigerant stored in the secondary space (S2). This limits the amount of refrigerant charged into the refrigerant circuit (10) and prevents the amount of refrigerant used in the refrigeration cycle from becoming insufficient.

[0105] (6-3) The compressor (20) of this embodiment satisfies the relational expression 0.2≦H2 / Hc, which ensures the oil separation function in the secondary space (S2), thereby reducing the oil rise rate.

[0106] (6-4) The refrigeration oil contains either a polyalkylene glycol, a polyvinyl ether, or a polyol ester.

[0107] By using these refrigeration oils, the hydrocarbon refrigerant is less likely to dissolve in the refrigeration oil. This prevents the viscous resistance of the refrigeration oil from decreasing, thereby reducing the oil rising rate. In addition, the dissolution viscosity of the first refrigeration oil does not become excessively low, which prevents wear on the sliding parts. In particular, by setting the molecular weight of the refrigeration oil to be between 1000 and 1800, the hydrocarbon refrigerant can be effectively prevented from dissolving in the refrigeration oil.

[0108] In addition, by preventing the hydrocarbon refrigerant from dissolving in the refrigeration oil in this manner, the amount of refrigerant held in the casing (21) is reduced, thereby limiting the amount of refrigerant charged into the refrigerant circuit (10) and preventing a shortage of the amount of refrigerant used in the refrigeration cycle.

[0109] (6-5) The refrigerating machine oil contains at least one of a phosphate ester extreme pressure additive, an antioxidant, and an acid scavenger.

[0110] When the refrigerating machine oil contains an antioxidant, the refrigerating machine oil contains 0.1 wt. % or more and 0.5 wt. % or less of the antioxidant. Hydrocarbon refrigerants have a chemically stable structure and are less likely to decompose during the refrigeration cycle than HFC refrigerants or HFO refrigerants. Therefore, even if the amount of antioxidant is 0.5 wt. % or less, the refrigerant can be used stably for a long period of time. Furthermore, by limiting the amount of antioxidant to 0.5 wt. %, a decrease in the viscosity of the refrigerating machine oil can be suppressed. As a result, the viscous resistance of the refrigerating machine oil increases, thereby reducing the oil rise rate α. In addition, wear on sliding parts can be suppressed.

[0111] When the refrigerating machine oil contains an acid scavenger, the refrigerating machine oil contains 0.1 wt. % or more and 0.5 wt. % or less of the acid scavenger. As described above, hydrocarbon refrigerants have a chemically stable structure and are less likely to decompose during the refrigeration cycle than HFC refrigerants or HFO refrigerants. Therefore, even if the amount of acid scavenger is 0.5 wt. % or less, the refrigerant can be used stably for a long period of time. Furthermore, by limiting the amount of antioxidant to 0.5 wt. %, a decrease in the viscosity of the refrigerating machine oil can be suppressed. As a result, the viscous resistance of the refrigerating machine oil increases, thereby reducing the oil rise rate α. In addition, wear on sliding parts can be suppressed.

[0112] When a refrigerating machine oil contains an extreme-pressure additive, the refrigerating machine oil contains 1.0 wt % or more and 5.0 wt % or less of the extreme-pressure additive. By limiting the amount of the extreme-pressure additive to 5.0 wt % or less, a decrease in the viscosity of the refrigerating machine oil can be prevented. As a result, the viscous resistance of the refrigerating machine oil increases, thereby reducing the oil rise rate α. In addition, wear on sliding parts can be suppressed.

[0113] (7) Other embodiments The rotary compressor may be a so-called rolling piston type in which a roller rotates eccentrically while a vane separate from the roller is in contact with the roller, or a so-called hinge vane type in which the roller rotates eccentrically with the tip of the vane rotatably fitted in a recess on the outer circumferential surface of the roller.

[0114] The compression mechanism (40) may have only one cylinder or may have three or more cylinders, i.e., the compression mechanism (40) may have only one compression section or may have three or more compression sections.

[0115] The air conditioner (1) may be an indoor multi-type having multiple indoor units. The air conditioner (1) may be a mobile type that adjusts the temperature of air in a target space such as a vehicle. The refrigeration cycle device may be a hot water supply device for generating hot water or a cooling device for generating cold water. The refrigeration cycle device may be an internal cooling device that cools the air inside the storage unit. The internal cooling device may be a stationary type intended for use in a warehouse, or a mobile type intended for use inside a shipping container or trailer.

[0116] The rotary compressor (20) may satisfy only the above formulas (1) and (2), but preferably also satisfies formula (3) or (4).

[0117] The first refrigeration oil is refrigeration oil that is at a height equal to or lower than the suction port (71a) in the oil reservoir (35). However, the first refrigeration oil is preferably refrigeration oil that is present below the suction port (71a), near the suction port (71a), or inside the suction port (71a).

[0118] 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, the above embodiments, modifications, and other embodiments may be combined or substituted as appropriate as long as the functionality of the subject matter of the present disclosure is not impaired.

[0119] The terms "first," "second," "third," etc. mentioned above are used to distinguish the terms to which these terms are attached, and do not limit the number or order of the terms. [Industrial Applicability]

[0120] INDUSTRIAL APPLICABILITY As described above, the present disclosure is useful for rotary compressors and refrigeration cycle devices. [Explanation of symbols]

[0121] 1. Air conditioning equipment (refrigeration cycle equipment) 10 Refrigerant circuit 20 Compressor 21 Casing 24 Discharge pipe 25 Electric motor 30 Rotation axis 40 Compression mechanism 51A, 51B cylinder 52A, 52B Roller 53A, 53B vanes 70 Oil supply mechanism 71a Intake port S interior space S1 primary space S2 Secondary space

Claims

1. an electric motor (25); a rotating shaft (30) connected to the electric motor (25); a compression mechanism (40) disposed below the electric motor (25) and driven by the rotary shaft (30) to compress a refrigerant; a casing (21) that houses the electric motor (25), the rotary shaft (30), and the compression mechanism (40) and is filled with high-pressure refrigerant discharged from the compression mechanism (40); an oil supply mechanism (70) having a suction port (71a) for sucking refrigeration oil accumulated in the bottom of the casing (21) and supplying the refrigeration oil to a sliding part; the compression mechanism (40) includes annular cylinders (51A, 51B), annular rollers (52A, 52B) that rotate eccentrically in the cylinders (51A, 51B), and vanes (53A, 53B) that form compression chambers in the cylinders (51A, 51B); the internal space (S) of the casing (21) includes a primary space (S1) between the compression mechanism (40) and the electric motor (25) and a secondary space (S2) above the electric motor (25); A discharge pipe (24) communicating with the secondary space (S2) is connected to the casing (21), The refrigerant is a single refrigerant consisting of a hydrocarbon refrigerant or a mixed refrigerant containing the hydrocarbon refrigerant, The displacement volume of the compression mechanism (40) is Vc [cc], The density of the refrigerant at 1.9 MPa and 75°C is Dg [g / cm 3 ], The rotation speed of the rotating shaft (30) is N [rps], The volume of the primary space (S1) is V1 [cc], The volume of the secondary space (S2) is V2 [cc], The height of the primary space (S1) is H1 [cm], The height of the secondary space (S2) is H2 [cm], The density of the refrigerating machine oil at 15°C is Do [g / cm 3 ], When the dissolved viscosity of the refrigeration oil present at a height position below the suction opening (71a) is defined as η [mPa·S], N≧100 [rps] and ((8.19 x 10 -8 × Vc × Dg + 0.000327) × Vc 3.657 ×N 3.126 ) / (V1 x V2 x H1 1.867 ×H2 1.556 × Do × η)≦1.0 Rotary compressor.

2. When the total height of the casing (21) is defined as Hc [cm], H2 / Hc≦0.25 The rotary compressor according to claim 1 .

3. When the total height of the casing (21) is defined as Hc [cm], 0.2≦H2 / Hc The rotary compressor according to claim 1 .

4. The refrigerating machine oil contains any one of polyalkylene glycol, polyvinyl ether, and polyol ester. The rotary compressor according to any one of claims 1 to 3.

5. The density of the refrigerant Do [g / cm 3 ] is 37 [g / cm 3 ] or more, 44[g / cm 3 ] or less The rotary compressor according to any one of claims 1 to 3.

6. The refrigerating machine oil contains at least one of an extreme pressure additive of a phosphate ester, an antioxidant, and an acid scavenger. The rotary compressor according to any one of claims 1 to 3.

7. The refrigerating machine oil contains 0.1% by weight or more and 0.5% by weight or less of an antioxidant or an acid scavenger. The rotary compressor according to claim 6.

8. The refrigerating machine oil contains 1.0 wt % or more and 5.0 wt % or less of an extreme pressure additive. The rotary compressor according to claim 6.

9. The molecular weight of the refrigerating machine oil is 1,000 or more and 1,800 or less. The rotary compressor according to any one of claims 1 to 3.

10. A refrigerant circuit (10) having the rotary compressor (20) according to any one of claims 1 to 3 and performing a refrigeration cycle using a hydrocarbon refrigerant. Refrigeration cycle equipment.

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