Rotary compressor

Abstract

A rotary compressor includes: a casing (16) that forms a first space (Si) in which a refrigerant at a suction pressure flows; an electric motor (10) disposed in the first space (Si); a drive shaft (70) that is rotated about its axis; and a compression mechanism (15) that compresses the refrigerant in the first space (Si) and discharges the compressed refrigerant from a discharge port (24, 29). The casing (16) forms the oil reservoir (85) that stores the refrigerating machine oil and the high-pressure gas space (HS) into which the refrigerant discharged from the discharge port (24, 29) flows and which communicates with the vane chambers (48, 49). The oil separation mechanism (82) that separates the refrigerant and the refrigerating machine oil discharged from the discharge port (24, 29) from each other is disposed in the high-pressure gas space (HS).

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a rotary compressor and a refrigeration cycle apparatus including the rotary compressor. The rotary compressor is a compressor that compresses gas in a compression chamber formed in a cylinder by eccentrically rotating a roller in the cylinder. The rotary compressor generally has a vane for partitioning the compression chamber. There are various types of rotary compressors, such as a so-called rolling roller compressor in which a roller eccentrically rotates while a vane separate from the roller abuts on the roller, a so-called swing compressor in which a vane integrally formed with the roller swings with the eccentric rotation of the roller, and a so-called hinge vane compressor in which the roller eccentrically rotates with a tip of the vane rotatably fitted in a recess of an outer peripheral surface of the roller.BACKGROUND ART

[0002] Patent Document 1 discloses a rotary compressor including an oil separator that separates a lubricant contained in a refrigerant. An oil supply passage is connected to the oil separator, and the lubricant separated by the oil separator flows through the oil supply passage and is supplied to a predetermined sliding portion of the compressor.CITATION LISTPATENT DOCUMENT

[0003] Patent Document 1: Japanese Unexamined Patent Publication No. 2012-202357SUMMARY OF THE INVENTIONTECHNICAL PROBLEM

[0004] According to Patent Document 1, the oil separator is disposed outside the rotary compressor. Thus, when the length of the oil supply passage connecting the oil separator and the sliding portion increases, the flow path resistance in the oil supply passage increases, and the amount of oil supplied to the sliding portion decreases.

[0005] An object of the present disclosure is to suppress the decrease in amount of oil supplied to the sliding portion of the rotary compressor.SOLUTION TO THE PROBLEM

[0006] A first aspect is directed to a rotary compressor, including: a casing (16) configured to form a first space (Si) in which a refrigerant at a suction pressure flows; an electric motor (10) disposed in the first space (Si); a drive shaft (70) configured to be rotated by the electric motor (10) about its axis; and a compression mechanism (15) configured to be driven by the drive shaft (70) to compress the refrigerant in the first space (Si) and discharge the compressed refrigerant from a discharge port (24, 29), wherein the compression mechanism (15) includes a cylinder (30, 35), a roller (40, 45) configured to rotate eccentrically in a cylinder chamber (S1, S2) surrounded by an inner wall of the cylinder (30, 35), a vane (41, 46) configured to be inserted into a vane chamber (48, 49) formed inside the cylinder (30, 35) and partition a cylinder chamber (S1, S2) formed by the space surrounded by the inner wall of the cylinder (30, 35) and the roller (40, 45) into a suction space (Ss) and a discharge space (Sd), a first end plate (20) configured to close one axial end of the cylinder (30, 35), and a second end plate (25) configured to close the other axial end of the cylinder (30, 35), the casing (16) forms an oil reservoir (85) configured to store refrigerating machine oil and a high-pressure gas space (HS) into which the refrigerant discharged from the discharge port (24, 29) flows and which communicates with the vane chamber (48, 49), and an oil separation mechanism (82) configured to separate the refrigerant and the refrigerating machine oil discharged from the discharge port (24, 29) from each other is disposed in the high-pressure gas space (HS).

[0007] In the first aspect, the oil separation mechanism (82) is disposed inside the casing (16). This can reduce the flow path length of the refrigerating machine oil from the oil separation mechanism (82) to the oil reservoir (85) and the flow path length of the refrigerating machine oil from the oil reservoir (85) to the sliding portion (particularly, the vane chamber (48, 49)). Thus, the resistance of the flow path of the refrigerating machine oil from the oil separation mechanism (82) to the oil reservoir (85) is reduced, suppressing the decrease in amount of the refrigerating machine oil supplied to the sliding portion.

[0008] A second aspect is an embodiment of the first aspect. In the second aspect, the oil reservoir (85) is formed in the high-pressure gas space (HS), and the rotary compressor further includes an oil supply passage (90) configured to supply the refrigerating machine oil in the oil reservoir (85) to the vane chamber (48, 49).

[0009] In the second aspect, the high-pressure gas space (HS) that supplies the refrigerating machine oil to the vane chamber (48, 49) is formed in the casing (16), shortening the oil supply passage (90) from the oil reservoir (85) to the vane chamber (48, 49). This can reduce the flow path resistance in the oil supply passage (90), suppressing the decrease in amount of oil supplied to the vane chamber (48, 49).

[0010] A third aspect is an embodiment of the first or second aspect. In the third aspect, the rotary compressor further includes: an inlet (83) through which the refrigerant compressed by the compression mechanism (15) flows into the high-pressure gas space (HS); and an outlet (84) through which the refrigerant in the high-pressure gas space (HS) flows out of the high-pressure gas space (HS), wherein the inlet (83) is disposed within a range of 90° to 270° from the outlet (84) in a circumferential direction of the casing (16) about the drive shaft (70).

[0011] In the third aspect, the distance from the inlet (83) to the outlet (84) can be increased. This can increase the length of the refrigerant flow path in the oil separation mechanism (82) disposed in the high-pressure gas space (HS), separating more oil from the refrigerant.

[0012] A fourth aspect is an embodiment of any one of the first to third aspects. In the fourth aspect, the oil reservoir (85) is provided at the bottom of the high-pressure gas space (HS), the rotary compressor further includes an oil supply passage (90) that supplies the refrigerating machine oil in the oil reservoir (85) to the vane chamber (48, 49), and a bottom of the high-pressure gas space (HS) has a tapered surface (81a) that is inclined downward toward the oil supply passage (90).

[0013] In the fourth aspect, the oil reservoir (85) is formed so that the refrigerating machine oil accumulates at a lower end of the oil supply passage (90). This allows easy supply of the refrigerating machine oil in the oil reservoir (85) to the oil supply passage (90).

[0014] A fifth aspect is an embodiment of the first or second aspect. In the fifth aspect, the rotary compressor further includes a muffler (61, 63) that forms a muffler chamber (62, 64) when the refrigerant discharged from the discharge port (24, 29) flows in, wherein the oil separation mechanism (82) is disposed inside the muffler chamber (62, 64) or the muffler (61, 63).

[0015] In the fifth aspect, the oil separation mechanism (82) also serves as a sound absorbing space, and thus, the increase in volume of the high-pressure gas space (HS) can be suppressed, and the amount of refrigerant filling the space can also be reduced.

[0016] A sixth aspect is an embodiment of the first or second aspect. In the sixth aspect, the oil separation mechanism (82) is provided inside the cylinder (30, 35).

[0017] In the sixth aspect, the oil separation mechanism (82) is provided inside the cylinder (30, 35), requiring no space for placing the oil separation mechanism (82). This can reduce the size of the casing (16).

[0018] A seventh aspect is an embodiment of any one of the first to sixth aspects. In the seventh aspect, the oil separation mechanism (82) includes: a porous or mesh member that separates the refrigerant and the refrigerating machine oil from each other when a refrigerant gas passes through the porous or mesh member or a plate member that separates the refrigerant and the refrigerating machine oil from each other when the refrigerant gas collides against the plate member.

[0019] In the seventh aspect, the refrigerant and the refrigerating machine oil can be separated from each other with a relatively simple mechanism. This can reduce the cost of the oil separation mechanism (82).

[0020] An eighth aspect is an embodiment of any one of the first to seventh aspects. In the eighth aspect, the compression mechanism (15) is a two-cylinder compression mechanism, and includes a first cylinder (30) and a second cylinder (35) arranged in an axial direction and a middle plate (50) disposed between the first cylinder (30) and the second cylinder (35), the rotary compressor further includes a communication passage (91) provided in the compression mechanism (15) to allow a first discharge port (24) for discharging the refrigerant compressed in the first cylinder (30) and a second discharge port (29) for discharging the refrigerant compressed in the second cylinder (35) to communicate with each other, and the communication passage (91) supplies the discharged refrigerant to the oil separation mechanism (82).

[0021] In the eighth aspect, the same effects as those of the first aspect can be achieved with a single oil separation mechanism (82) by providing the communication passage (91) in the two-cylinder rotary compressor.

[0022] A ninth aspect is directed to a refrigeration cycle apparatus including the rotary compressor of any one of the first to eighth aspects.

[0023] In the ninth aspect, a refrigeration cycle apparatus including the rotary compressor of the present disclosure can be provided.BRIEF DESCRIPTION OF THE DRAWINGS

[0024] [FIG. 1] FIG. 1 is a configuration diagram of a refrigerant circuit of a refrigeration cycle apparatus of an embodiment. [FIG. 2] FIG. 2 is a vertical cross-sectional view of a rotary compressor. [FIG. 3A] FIG. 3A is a horizontal cross-sectional view of a first compression mechanism. [FIG. 3B] FIG. 3B is a horizontal cross-sectional view of a second compression mechanism. [FIG. 4] FIG. 4 shows the operation of the first compression mechanism and the second compression mechanism. [FIG. 5] FIG. 5 is a vertical cross-sectional view of a rotary compressor according to a first variation. [FIG. 6] FIG. 6 is a cross-sectional view of the rotary compressor shown in FIG. 5 as viewed from the direction of arrows V-V. [FIG. 7] FIG. 7 is a vertical cross-sectional view of a rotary compressor according to a second variation. [FIG. 8] FIG. 8 is a vertical cross-sectional view of the rotary compressor according to the second variation as viewed from a direction different from the direction shown in FIG. 7. [FIG. 9] FIG. 9 is a vertical cross-sectional view of a rotary compressor according to a third variation. [FIG. 10] FIG. 10 is a cross-sectional view of the rotary compressor shown in FIG. 9 as viewed from the direction of arrows X-X. [FIG. 11] FIG. 11 is a vertical cross-sectional view of a rotary compressor according to a fourth variation. [FIG. 12] FIG. 12 is a vertical cross-sectional view of the rotary compressor according to the fourth variation as viewed from a direction different from the direction shown in FIG. 11. [FIG. 13] FIG. 13 is a vertical cross-sectional view of a rotary compressor according to a fifth variation. [FIG. 14] FIG. 14 is a schematic view of a configuration of an oil separation mechanism according to another embodiment. DESCRIPTION OF EMBODIMENTS

[0025] Embodiments of the present invention will be described below with reference to the drawings. The following embodiments are merely exemplary ones in nature, and are not intended to limit the scope, application, or uses of the invention. Features of the embodiments, variations, and other examples described below can be combined or partially substituted within the range where the present invention can be embodied.(1) Refrigeration Cycle Apparatus

[0026] As illustrated in FIG. 1, a rotary compressor (1) of this example is applied to a refrigeration cycle apparatus (100). The refrigeration cycle apparatus (100) is an air conditioner for conditioning air in an indoor space, for example. The refrigeration cycle apparatus (100) has an outdoor unit (7) disposed in an outdoor space and an indoor unit (8) disposed in the indoor space. The outdoor unit (7) includes the rotary compressor (1), a four-way switching valve (3), an outdoor heat exchanger (4), and an expansion valve (5). The indoor unit (8) includes an indoor heat exchanger (6).

[0027] The refrigeration cycle apparatus (100) includes a refrigerant circuit (9). The rotary compressor (1), the four-way switching valve (3), the outdoor heat exchanger (4), the expansion valve (5), and the indoor heat exchanger (6) are connected to the refrigerant circuit (9). A refrigeration cycle is performed as the refrigerant flows through the refrigerant circuit (9).

[0028] The refrigeration cycle apparatus (100) performs a heating operation and a cooling operation by switching the four-way switching valve (3). In the cooling operation, a first refrigeration cycle is performed. Specifically, when a first port (P1) and a third port (P3) of the four-way switching valve (3) communicate with each other, and a second port (P2) and a fourth port (P4) communicate with each other (solid lines in FIG. 1), the indoor heat exchanger (6) functions as an evaporator, and the outdoor heat exchanger (4) functions as a radiator. In the heating operation, a second refrigeration cycle is performed. Specifically, when the first port (P1) and the fourth port (P4) of the four-way switching valve (3) communicate with each other, and the second port (P2) and the third port (P3) communicate with each other (dashed lines in FIG. 1), the indoor heat exchanger (6) functions as a radiator, and the outdoor heat exchanger (4) functions as an evaporator.(2) Rotary Compressor

[0029] The rotary compressor (1) illustrated in FIG. 2 is a so-called low-pressure dome compressor in which a sucked refrigerant forms a low-pressure space in the casing (16). Hereinafter, the rotary compressor (1) of the present disclosure may be simply referred to as a compressor. The compressor (1) includes a casing (16), an electric motor (10), a drive shaft (70), a compression mechanism (15), and an oil separation mechanism (82). The oil separation mechanism (82) will be described later.(2-1) Casing

[0030] The casing (16) is a cylindrical closed container standing upright. The casing (16) includes a cylindrical barrel (17), and an upper end plate (18) and a lower end plate (19) that close the ends of the barrel (17). The casing (16) houses the compression mechanism (15) and the electric motor (10). The electric motor (10) and the compression mechanism (15) are arranged in the casing (16) in this order from the top. The casing (16) is provided with a suction pipe (53), a discharge pipe (54), and an introduction pipe (55). An oil reservoir (not shown) that supplies refrigerating machine oil to a bearing of the compression mechanism (15) described later is formed at the bottom of the casing (16).

[0031] The suction pipe (53) introduces the sucked refrigerant into the casing (16). Thus, a first space (Si) into which the refrigerant at a suction pressure flows is formed in the casing (16). The first space (Si) is a low-pressure space filled with the refrigerant at a suction pressure. The first space (Si) is a suction pressure space or a low-pressure space. In this embodiment, the first space (Si) is a space excluding the inside of the compression mechanism (15). The suction pipe (53) is connected to the barrel (17). Specifically, the suction pipe (53) penetrates the barrel (17) at a height position between the electric motor (10) and the compression mechanism (15).

[0032] The refrigerant compressed in the compression mechanism (15) is discharged outside the casing (16) through the discharge pipe (54). The discharge pipe (54) is connected to the barrel (17). Specifically, one end of the discharge pipe (54) is connected to the barrel (17) at a height position below the compression mechanism (15).

[0033] The introduction pipe (55) introduces the refrigerant at the suction pressure in the first space (Si) into the compression mechanism (15). Specifically, one end of the introduction pipe (55) is connected to the upper end plate (18). The other end of the introduction pipe (55) extends outside the casing (16) and then branches into two. A first outflow end, which is one of the branched end, communicates with a first suction port (33) of a first compression mechanism (K1) described later. A second outflow end, which is the other branched end, communicates with a suction port (33, 38) of a second compression mechanism (K2) described later.(2-2) Electric Motor

[0034] The electric motor (10) is disposed in the first space (Si). Specifically, the electric motor (10) is disposed in an upper portion of the internal space of the casing (16). The electric motor (10) includes a stator (11) and a rotor (12). The stator (11) is fixed to the barrel (17) of the casing (16). The rotor (12) is attached to a drive shaft (70), which will be described later, of the compression mechanism (15). The drive shaft (70) extends downward from the electric motor (10). The drive shaft (70) extends downward from the electric motor (10) to coincide with the axis of the casing (16). The drive shaft (70) is rotated about an axis of the drive shaft (70) by the electric motor (10). Details of the drive shaft (70) will be described later.(2-3) Compression Mechanism

[0035] The compression mechanism (15) illustrated in FIGS. 2, 3A, and 3B is a so-called swinging roller type rotary fluid machine. The compression mechanism (15) is connected to the drive shaft (70). The compression mechanism (15) is driven by the drive shaft (70) to compress the refrigerant in the first space (Si) and discharge the compressed refrigerant from a discharge port (24, 29).

[0036] The compression mechanism (15) of this embodiment is a two-cylinder rotary fluid machine including a first compression mechanism (K1) and a second compression mechanism (K2). Each of the first compression mechanism (K1) and the second compression mechanism (K2) includes a cylinder (30, 35), a roller (40, 45), and a vane (41, 46). Each of the cylinders (30, 35) includes a pair of bushings (42, 47).

[0037] The compression mechanism (15) includes a front muffler (61), a front head (20), a first cylinder (30), a middle plate (50), a second cylinder (35), a rear head (25), and a rear muffler (63). The front muffler (61), the front head (20), the first cylinder (30), the middle plate (50), the second cylinder (35), the rear head (25), and the rear muffler (63) are arranged in the casing (16) in this order from top to bottom. The front head (20), the first cylinder (30), the middle plate (50), the second cylinder (35), and the rear head (25) are fastened to each other with bolts (not shown). The front head (20) of the compression mechanism (15) is fixed to the barrel (17) of the casing (16).(2-3-1) First and Second Compression Mechanisms

[0038] The first compression mechanism (K1) includes a first cylinder (30), a first roller (40), and a first vane (41). The second compression mechanism (K2) includes a second cylinder (35), a second roller (45), and a second vane (46). In the compression mechanism (15), the first compression mechanism (K1) and the second compression mechanism (K2) are stacked in the up-down direction with the middle plate (50) interposed therebetween. In this embodiment, the first compression mechanism (K1) and the second compression mechanism (K2) are configured in the same manner except for the suction port (33, 38). The difference between the first compression mechanism (K1) and the second compression mechanism (K2) will be described later.(2-3-2) Cylinder

[0039] The two cylinders (30, 35) are housed inside the casing (16). Each of the cylinders (30, 35) is a thick disk-shaped member. Each of the cylinders (30, 35) has an inner wall and a vane receiving hole (32, 37). A first suction port (33) is formed in the first cylinder (30). A second suction port (38) is formed in the second cylinder (35).

[0040] The first cylinder (30) and the second cylinder (35) have the same thickness. Although not shown in FIG. 2, each cylinder (30, 35) has a plurality of through holes penetrating the cylinder (30, 35) in the thickness direction, such as through holes for receiving bolts for assembling the compression mechanism (15).

[0041] The cylinder (30, 35) is formed in an annular shape. The cylinder (30, 35) has an inner peripheral surface (31, 36) and an outer peripheral surface. The inner peripheral surface (31, 36) of the cylinder (30, 35) constitutes an inner wall of the cylinder (30, 35). An inner peripheral surface (31, 36) of the cylinder defines a cylinder chamber (S1, S2) described later. The inner peripheral surface (31, 36) of the cylinder (30, 35) includes a first inner peripheral surface (31) of the first cylinder (30) and a second inner peripheral surface (36) of the second cylinder (35).

[0042] The vane receiving hole (32, 37) is a hole extending from the inner peripheral surface (31, 36) of the cylinder (30, 35) to the outside in the radial direction of the cylinder (30, 35). The vane receiving hole (32, 37) penetrates the cylinder (30, 35) in the thickness direction. The vane receiving hole (32, 37) of the first cylinder (30) is a first vane receiving hole (32). The vane receiving hole (32, 37) of the second cylinder (35) is a second vane receiving hole (37).

[0043] The vane receiving hole (32, 37) forms a vane chamber (48, 49) that houses the vane (41, 46). The vane chamber (48, 49) is formed inside the cylinder (30, 35). Specifically, the vane chamber (48, 49) includes a first vane chamber (48) and a second vane chamber (49). The first vane chamber (48) houses the first vane (41). The first vane chamber (48) is a space defined by an inner wall surface of the first vane receiving hole (32), the front head (20), and the middle plate (50). The second vane chamber (49) houses the second vane (46). The second vane chamber (49) is a space defined by an inner wall surface of the second vane receiving hole (37), the middle plate (50), and the rear head (25).

[0044] In FIG. 3, the first suction port (33) is disposed on the right of the first vane receiving hole (32), and the second suction port (38) is disposed on the right of the second vane receiving hole (37). Each of the suction ports (33, 38) communicates with a suction space (Ss) described later.(2-3-3) Front Head

[0045] The front head (20) shown in FIG. 2 is a member that closes an end face of the first cylinder (30) facing the electric motor (10) (an upper end face of the first cylinder (30) shown in FIG. 2). The front head (20) includes a body (21), a main bearing (22), and an outer peripheral wall (23). The body (21), the main bearing (22), and the outer peripheral wall (23) are integrally formed. The front head (20) is an example of a first end plate (20) that closes one axial end of the cylinder (30, 35).

[0046] The body (21) has a substantially circular thick plate shape. The body (21) is disposed to cover the end face of the first cylinder (30). A lower surface of the body (21) is in close contact with the first cylinder (30). The main bearing (22) is formed in a cylindrical shape extending from the body (21) toward the electric motor (10) (upward in FIG. 1). The main bearing (22) is disposed in a central portion of the body (21). The main bearing (22) constitutes a journal bearing that supports the drive shaft (70) of the compression mechanism (15). The outer peripheral wall (23) is a thick annular portion formed continuously from the outer periphery of the body (21).

[0047] The front head (20) has a first discharge port (24). The first discharge port (24) is an example of the discharge port (24, 29) of the present disclosure. The first discharge port (24) discharges the refrigerant compressed by the first cylinder (30). The first discharge port (24) penetrates the body (21) of the front head (20) in its thickness direction. The first discharge port (24) is disposed on a lateral side of the first vane receiving hole (32). The body (21) of the front head (20) is provided with a discharge valve (not shown) for opening and closing the first discharge port (24).(2-3-4) Rear Head

[0048] The rear head (25) shown in FIG. 2 is a member that closes an end face of the second cylinder (35) facing opposite to the electric motor (10) (a lower end face of the second cylinder (35) shown in FIG. 2). The rear head (25) includes a body (26), an auxiliary bearing (27), and an outer peripheral wall (28). The rear head (25) is an example of a second end plate (25) that closes the other axial end of the cylinder (30, 35).

[0049] The body (26) is formed into a substantially circular thick plate shape. The body (26) is disposed to cover the end face of the second cylinder (35). An upper surface of the body (26) is in close contact with the second cylinder (35). The auxiliary bearing (27) is formed in a cylindrical shape extending from the body (26) in a direction opposite to the second cylinder (35) (downward in FIG. 2). The auxiliary bearing (27) is disposed in a central portion of the body (26). The auxiliary bearing (27) constitutes a journal bearing that supports the drive shaft (70) of the compression mechanism (15). The outer peripheral wall (28) is formed in a cylindrical shape extending from the outer periphery of the body (26) in a direction opposite to the second cylinder (35).

[0050] The rear head (25) has a second discharge port (29). The second discharge port (29) is an example of the discharge port (24, 29) of the present disclosure. The second discharge port (29) discharges the refrigerant compressed by the second cylinder (35). The second discharge port (29) penetrates the body (26) of the rear head (25) in its thickness direction. The second discharge port (29) is disposed on the left of the second vane receiving hole (37). The body (26) of the rear head (25) is provided with a discharge valve (not shown) for opening and closing the second discharge port (29).(2-3-5) Middle Plate

[0051] The middle plate (50) shown in FIG. 2 is sandwiched between the first cylinder (30) and the second cylinder (35). The middle plate (50) is in close contact with a lower end face of the first cylinder (30) and an upper end face of the second cylinder (35).

[0052] A central hole (51) is formed in a central portion of the middle plate (50) to penetrate the middle plate (50) in the thickness direction. An intermediate coupling portion (78) of the drive shaft (70), which will be described later, is inserted in the central hole (51) of the middle plate (50).(2-3-6) Front Muffler and Rear Muffler

[0053] The front muffler (61) shown in FIG. 2 is disposed above the front head (20) to cover the first discharge port (24). The front muffler (61) is an example of a muffler (61) of the present disclosure. A front muffler chamber (62) is formed between the front muffler (61) and the front head (20). The front muffler chamber (62) is a muffler chamber (62, 64) into which the refrigerant discharged from the first discharge port (24) flows. Thus, the front muffler chamber (62) is provided in the first end plate (20). The refrigerant discharged from the first discharge port (24) forms a high-pressure gas space (HS) in the front muffler chamber (62).

[0054] The rear muffler (63) shown in FIG. 2 is disposed below the rear head (25) to cover the second discharge port (29). The rear muffler (63) is an example of a muffler (63) of the present disclosure. A rear muffler chamber (64) is formed between the rear muffler (63) and the rear head (25). The rear muffler chamber (64) is a muffler chamber (62, 64) into which the refrigerant discharged from the second discharge port (29) flows. Thus, the rear muffler chamber (64) is provided in the second end plate (25). The refrigerant discharged from the second discharge port (29) forms a high-pressure gas space (HS) in the rear muffler chamber (64).(2-3-7) Drive Shaft

[0055] As illustrated in FIGS. 2 and 3, the drive shaft (70) is a member that drives a roller (40, 45) described later. Specifically, the drive shaft (70) includes a main shaft portion (72), a first eccentric portion (75), an intermediate coupling portion (78), a second eccentric portion (76), and an auxiliary shaft portion (74) (see FIG. 1). A rotation axis (70a) of the drive shaft (70) substantially coincides with the axes of the cylinders (30, 35).

[0056] In the drive shaft (70), the main shaft portion (72), the first eccentric portion (75), the intermediate coupling portion (78), the second eccentric portion (76), and the auxiliary shaft portion (74) are arranged in this order from top to bottom. In the drive shaft (70), the main shaft portion (72), the first eccentric portion (75), the intermediate coupling portion (78), the second eccentric portion (76), and the auxiliary shaft portion (74) are formed integrally with each other.

[0057] Each of the main shaft portion (72) and the auxiliary shaft portion (74) is a cylindrical or rod-shaped portion having a circular cross section. The rotor (12) of the electric motor (10) is attached to an upper part of the main shaft portion (72). A lower part of the main shaft portion (72) constitutes a journal supported by the main bearing (22) of the front head (20). The auxiliary shaft portion (74) constitutes a journal supported by the auxiliary bearing (27) of the rear head (25). The center axis of the main shaft portion (72) and the center axis of the auxiliary shaft portion (74) coincide with the rotation axis (70a) of the drive shaft (70).

[0058] The eccentric portions (75, 76) are cylindrical portions each having a diameter larger than the main shaft portion (72). Each of the eccentric portions (75, 76) has a center axis that is eccentric to the rotation axis (70a) of the drive shaft (70). The first eccentric portion (75) is eccentric relative to the rotation axis (70a) of the drive shaft (70) in a direction away from the second eccentric portion (76). In other words, the direction of eccentricity of the first eccentric portion (75) relative to the rotation axis (70a) of the drive shaft (70) is different by 180° from the direction of eccentricity of the second eccentric portion (76) relative to the rotation axis (70a) of the drive shaft (70).

[0059] Eccentricity e1 of the first eccentric portion (75) and eccentricity e2 of the second eccentric portion (76) are equal to each other. The eccentricity e1 of the first eccentric portion (75) is a distance between a center axis (75a) of the first eccentric portion (75) and the rotation axis (70a) of the drive shaft (70). The eccentricity e2 of the second eccentric portion (76) is a length between a center axis (76a) of the second eccentric portion (76) and the rotation axis (70a) of the drive shaft (70).

[0060] The outer diameter of the first eccentric portion (75) is equal to the outer diameter of the second eccentric portion (76). The first eccentric portion (75) and the second eccentric portion (76) have substantially the same height (length in the up-down direction).

[0061] The intermediate coupling portion (78) is disposed between the first eccentric portion (75) and the second eccentric portion (76) to couple the first eccentric portion (75) and the second eccentric portion (76).(2-3-8) Roller

[0062] The roller (40, 45) that rotates eccentrically is disposed in a space surrounded by the inner peripheral surface (31, 36) of the cylinder (30, 35). The space surrounded by the inner peripheral surface (31, 36) of the cylinder (30, 35) and the roller (40, 45) form a cylinder chamber (S1, S2). The roller (40, 45) includes a first roller (40) and a second roller (45). The first roller (40) and the second roller (45) are members having the same shape and dimensions and are made of the same material. Each of the rollers (40, 45) is a slightly thick cylindrical member. The first roller (40) is disposed in the first cylinder (30). The second roller (45) is disposed in the second cylinder (35).

[0063] The cylinder chamber (S1, S2) includes a first cylinder chamber (S1) and a second cylinder chamber (S2). The first cylinder chamber (S1) is a space defined by the first roller (40), the first inner peripheral surface (31), the front head (20), and the middle plate (50). The second cylinder chamber (S2) is a space defined by the second roller (45), the second inner peripheral surface (36), the middle plate (50), and the rear head.

[0064] The first eccentric portion (75) of the drive shaft (70) is inserted in the first roller (40). The first roller (40) rotates eccentrically as the first eccentric portion (75) of the drive shaft (70) rotates.

[0065] An outer peripheral surface of the first roller (40) slides against the first inner peripheral surface (31). An upper surface of the first roller (40) slides against the lower surface of the body (21) of the front head (20). A lower surface of the first roller (40) slides against the upper surface of the middle plate (50).

[0066] The second eccentric portion (76) of the drive shaft (70) is inserted in the second roller (45). The second roller (45) rotates eccentrically as the second eccentric portion (76) of the drive shaft (70) rotates.

[0067] An outer peripheral surface of the second roller (45) slides against the second inner peripheral surface (36). A lower surface of the second roller (45) slides against the upper surface of the body (21) of the rear head (25). An upper surface of the second roller (45) slides against the lower surface of the middle plate (50).(2-3-9) Vane

[0068] As illustrated in FIG. 3, the first vane (41) and the second vane (46) are slightly thick, flat rectangular plate-shaped members. The thickness of each of the vanes (41, 46) in the up-down direction (the axial direction of the drive shaft (70)) is the same as the thickness of the roller (40, 45) in the up-down direction. Each vane (41, 46) is inserted in the vane chamber (48, 49) and divides the cylinder chamber (S1, S2) into a suction space (Ss) and a discharge space (Sd).

[0069] Specifically, the first vane (41) is formed integrally with the first roller (40). The first vane (41) extends outward in the radial direction of the first roller (40) from the outer peripheral surface of the first roller (40). A radially outer end of the first vane (41) may be referred to as a tip of the first vane (41). The first vane (41) is disposed with the tip of the first vane (41) located in the first vane chamber (48). The first vane (41) divides the inside of the first cylinder chamber (S1) into the suction space (Ss) and the discharge space (Sd). The suction space (Ss) of the first cylinder chamber (S1) communicates with the first suction port (33). The discharge space (sd) of the first cylinder chamber (S1) communicates with the first discharge port (24).

[0070] The second vane (46) is formed integrally with the second roller (45). The second vane (46) extends outward in the radial direction of the second roller (45) from the outer peripheral surface of the second roller (45). A radially outer end of the second vane (46) may be referred to as a tip of the second vane (46). The second vane (46) is disposed with the tip of the second vane (46) located in the second vane chamber (49). The second vane (46) divides the inside of the second cylinder chamber (S2) into the suction space (Ss) and the discharge space (Sd). The suction space (Ss) of the second cylinder chamber (S2) communicates with the second suction port (38). The discharge space (Sd) of the second cylinder chamber (S2) communicates with the second discharge port (29).(2-3-10) Bushing

[0071] The cylinder (30, 35) is provided with bushings (42, 47). The bushings (42, 47) are a pair of semicircular plate-shaped members arranged to face each other with the vane (41, 46) interposed therebetween. Flat surfaces of the pair of semicircular members sandwich the vane (41, 46). The bushings (42, 47) include a first bushing (42) and a second bushing (47). The first bushing (42) is provided in the first cylinder (30). The second bushing (47) is provided in the second cylinder (35).

[0072] The first bushing (42) supports the first vane (41). The first vane (41) is supported by the first cylinder (30) via the first bushing (42) to be swingable and movable back and forth. Thus, the first roller (40) serves as a swing roller that swings about the center axis (75a) of the first eccentric portion (75) while revolving along the inner wall surface of the first cylinder (30) as the drive shaft (70) rotates.

[0073] The second bushing (47) supports the second vane (46). The second vane (46) is supported by the second cylinder (35) via the second bushing (47) to be swingable and movable back and forth. Thus, the second roller (45) serves as a swing roller that swings about the center axis (76a) of the second eccentric portion (76) while revolving along the inner wall surface of the second cylinder (35) as the drive shaft (70) rotates.(3) Operation of Compressor

[0074] An operation of the compressor (1) will be described with reference to FIG. 4. When the drive shaft (70) is driven by the electric motor (10), the rollers (40, 45) of the compression mechanism (15) are driven by the drive shaft (70). Each of the rollers (40, 45) is periodically displaced in the corresponding cylinder (30, 35) as illustrated in FIG. 4 each time the drive shaft (70) makes one rotation. In the rotary compressor (1), each of the first compression mechanism (K1) and the second compression mechanism (K2) of the compression mechanism (15) performs the suction, compression, and discharge of the refrigerant.(4) Operation of Compression Mechanism

[0075] As described above, in the compression mechanism (15) of this embodiment, the rollers (40, 45) in the first compression mechanism (K1) and the second compression mechanism (K2) are eccentric in directions different from each other. In other words, the direction of the eccentricity of the first roller (40) relative to the rotation axis (70a) of the drive shaft (70) is different by 180° from the direction of the eccentricity of the second roller (45) relative to the rotation axis (70a) of the drive shaft (70). Thus, the cycle of the displacement of the first roller (40) and the cycle of the displacement of the second roller (45) are shifted by 180° (i.e., a half cycle).

[0076] In each of the cylinders (30, 35), the volumes of the suction space (Ss) and the discharge space (Sd) in the cylinder chamber (S1, S2) vary with the displacement of the roller (40, 45). Thus, in each cylinder (30, 35), a suction phase in which the refrigerant is sucked into the cylinder chamber (S1, S2) through the suction port (33, 38), a compression phase in which the refrigerant sucked into the cylinder chamber (S1, S2) is compressed, and a discharge phase in which the compressed refrigerant is discharged through the discharge port (24, 29) are carried out.

[0077] Hereinafter, the operations of the first compression mechanism (K1) and the second compression mechanism (K2) will be described. As for the angles shown in FIG. 4, the drive shaft (70) is at a rotational angle of 0° when the first vane (41) of the first compression mechanism (K1) is located furthest from the first cylinder (30), and the drive shaft (70) is at a rotational angle of 180° when the first vane (41) of the first compression mechanism (K1) is located at the deepest point in the first cylinder (30).(4-1) Operation of First Compression Mechanism

[0078] In the first compression mechanism (K1), when the drive shaft (70) slightly rotates clockwise in FIG. 4 from the position at a rotational angle of 0°, a contact point between the first roller (40) and the first cylinder (30) passes through the first suction port (33). At this time, the suction of the refrigerant into the suction space (Ss) of the first cylinder (30) begins (suction phase).

[0079] The volume of the suction space (Ss) gradually increases as the rotational angle of the drive shaft (70) increases, and the amount of refrigerant sucked into the suction space (Ss) increases. The suction phase continues until the rotational angle of the drive shaft (70) reaches 360°, and then the operation proceeds from the suction phase to the compression phase and the discharge phase.

[0080] When the drive shaft (70) slightly rotates from the position at the rotational angle of 0°, the contact point between the first roller (40) and the first cylinder (30) passes through the first suction port (33) again. At this time, the refrigerant is completely sealed in the suction space (Ss). Thereafter, the suction space (Ss) connected to the first suction port (33) turns to the discharge space (Sd) connected to the first discharge port (24) only.

[0081] From this state, the compression of the refrigerant in the discharge space (Sd) begins. The volume of the discharge space (Sd) decreases as the rotational angle of the drive shaft (70) increases, and the pressure in the discharge space (Sd) increases. When the pressure in the discharge space (Sd) exceeds a predetermined pressure, the discharge valve opens. At this time, the refrigerant in the discharge space (Sd) is discharged outside the compression mechanism (15) through the first discharge port (24).

[0082] The compression phase and the discharge phase continue until the rotational angle of the drive shaft (70) reaches 360°, and then the operation proceeds from the compression phase and the discharge phase to the suction phase. In this way, a series of the suction phase, the compression phase, and the discharge phase is repeated in the first compression mechanism (K1), and thus the refrigerant is continuously compressed.(4-2) Operation of Second Compression Mechanism

[0083] In the second compression mechanism (K2), when the drive shaft (70) slightly rotates clockwise in FIG. 4 from the position at a rotational angle of 180°, a contact point between the second roller (45) and the second cylinder (35) passes through the second suction port (38). At this time, the suction of the refrigerant into the suction space (Ss) of the second cylinder (35) begins (suction phase).

[0084] The volume of the suction space (Ss) gradually increases as the rotational angle of the drive shaft (70) increases, and the amount of refrigerant sucked into the suction space (Ss) increases. The suction phase of the refrigerant continues until the rotational angle of the drive shaft (70) reaches 180°, and then the operation proceeds from the suction phase to the compression phase and the discharge phase.

[0085] When the drive shaft (70) slightly rotates from the position at the rotational angle of 180°, the contact point between the second roller (45) and the second cylinder (35) passes through the second suction port (38) again. At this time, the refrigerant is completely sealed in the suction space (Ss), and the suction space (Ss) connected to the first suction port (33) turns to the discharge space (Sd) connected to the second discharge port (29) only.

[0086] From this state, the compression of the refrigerant in the discharge space (Sd) begins. The volume of the discharge space (Sd) decreases as the rotational angle of the drive shaft (70) increases, and the pressure in the discharge space (Sd) increases. When the pressure in the discharge space (Sd) exceeds a predetermined pressure, the discharge valve opens. At this time, the refrigerant in the discharge space (Sd) is discharged outside the compression mechanism (15) through the second discharge port (29).

[0087] The compression phase and the discharge phase continue until the rotational angle of the drive shaft (70) reaches 180°, and then the operation proceeds from the compression phase and the discharge phase to the suction phase. In this way, a series of the suction phase, the compression phase, and the discharge phase is repeated in the second compression mechanism (K2), and thus the refrigerant is continuously compressed.(5) Oil Separator

[0088] As illustrated in FIG. 2, the rotary compressor (1) of this embodiment includes an oil separator (80) that separates the refrigerating machine oil from the refrigerant in the compressor (1). Part of the refrigerant is present in the compressor (1) as a mixture with the refrigerating machine oil. The oil separator (80) separates the refrigerating machine oil from a fluid mixture of the refrigerating machine oil and the refrigerant. The separated refrigerating machine oil is supplied to a predetermined portion of the compression mechanism (15). In this embodiment, the refrigerating machine oil separated by the oil separator (80) is supplied to the vane chamber (48, 49). Hereinafter, the "separation of the refrigerating machine oil from the fluid mixture" may be referred to as the "separation of the refrigerating machine oil from the refrigerant" for convenience.

[0089] The oil separator (80) is disposed below the rear muffler (63). The oil separator (80) includes a housing (81) and an oil separation mechanism (82) disposed in the housing (81).

[0090] The housing (81) is formed in a substantially cylindrical shape. The inside of the housing (81), to which the refrigerant discharged from the first discharge port (24) and the second discharge port (29) flows, communicates with the vane chamber (48, 49). Thus, a high-pressure gas space (HS) is formed inside the housing (81). The housing (81) is provided with a gas inlet (83) and a gas outlet (84).

[0091] The gas inlet (83) is an inflow port through which the refrigerant compressed by the compression mechanism (15) flows into the housing (81). The gas inlet (83) communicates with the first discharge port (24) and the second discharge port (29). The gas inlet (83) communicates with the downstream end of the discharge gas passage (91).

[0092] The gas outlet (84) is an outflow port through which the refrigerant in the housing (81) flows out of the housing (81). The gas outlet (84) communicates with the discharge pipe (54).

[0093] An oil reservoir (85) that stores the refrigerating machine oil is formed in the housing (81). The oil reservoir (85) is formed at the bottom of the housing (81). The bottom of the casing (16) has an inclined tapered surface (81a). Thus, the refrigerating machine oil in the oil reservoir (85) accumulates at the lower end of the tapered surface (81a). Specifically, an oil supply passage (90) for supplying the refrigerating machine oil in the oil reservoir (85) to each vane chamber is connected to the housing (81), and an inlet end of the oil supply passage (90) is disposed in the oil reservoir (85). The tapered surface (81a) is inclined downward toward the inlet end of the oil supply passage (90).

[0094] The oil separation mechanism (82) separates the refrigerant and the refrigerating machine oil discharged from the discharge port (24, 29). The oil separation mechanism (82) of the present embodiment is a mesh member. The mesh member separates the refrigerant and the refrigerating machine oil from each other when a refrigerant gas passes through the mesh member. The mesh member is provided in the housing (81) to extend from the gas inlet (83) to the gas outlet (84). This allows the refrigerating machine oil to be separated from the refrigerant flowing in the housing (81) from the gas inlet (83) to the gas outlet (84).(6) Discharge Gas Passage and Oil Supply Passage

[0095] The discharge gas passage (91) indicated by a broken arrow in FIG. 2 is a communication passage (91) through which the first discharge port (24) and the second discharge port (29) communicate with each other. Specifically, the discharge gas passage (91) passes through the first cylinder (30), the middle plate (50), the second cylinder (35), and the rear muffler (63) in the up-down direction.

[0096] The oil supply passage (90) allows the oil reservoir (85) to communicate with each vane chamber (48, 49). The oil supply passage (90) passes through the rear muffler (63), the rear head (25), and the middle plate (50) in the up-down direction (as indicated by a two-dot-dash arrow in FIG. 2). An outlet end of the oil supply passage (90) communicates with the first vane chamber (48) in the first cylinder (30) and communicates with the second vane chamber (49) in the second cylinder (35). An inlet end of the oil supply passage (90) is disposed in the oil reservoir (85).(7) Flows of Discharged Refrigerant and Refrigerating Machine Oil

[0097] The high-pressure refrigerant discharged from the first discharge port (24) to the front muffler chamber (62) flows through the discharge gas passage (91) toward the rear muffler chamber. The high-pressure refrigerant in the discharge gas passage (91) merges with the high-pressure refrigerant discharged from the second discharge port (29) in the rear muffler chamber (64) (see the broken arrow in FIG. 2).

[0098] The high-pressure refrigerant flowing from the rear muffler (63) into the oil separator (80) through the gas inlet (83) goes through the housing (81) toward the gas outlet (84). In the housing (81), the refrigerating machine oil is separated from the high-pressure refrigerant passing through the oil separation mechanism (82). The high-pressure refrigerant flows into the discharge pipe (54) through the gas outlet (84). The refrigerating machine oil separated from the refrigerant falls to the bottom of the housing (81) and is stored in the oil reservoir (85).

[0099] The discharged refrigerant creates high pressure in the space in the housing (81), causing the refrigerating machine oil in the oil reservoir to flow into the oil supply passage (90) toward the vane chamber (48, 49) with a lower pressure. The refrigerating machine oil flowed into the oil supply passage (90) goes up in the oil supply passage (90) (as indicated by the two-dot-dash arrow in FIG. 2), and is delivered to each of the second vane chamber (49) and the first vane chamber (48). The refrigerating machine oil flowed into the second vane chamber (49) is supplied to a sliding portion with which the second bushing (47) and the second vane (46) contact. The refrigerating machine oil flowed into the first vane chamber (48) is supplied to a sliding portion with which of the first bushing (42) and the first vane (41) contact.(8) Features(8-1) First Feature

[0100] In the rotary compressor (1) of this embodiment, the casing (16) forms the oil reservoir (85) that stores the refrigerating machine oil and the high-pressure gas space (HS) into which the refrigerant discharged from the discharge port (24, 29) flows and which communicates with the vane chambers (48, 49). The oil separation mechanism (82) that separates the refrigerant and the refrigerating machine oil discharged from the discharge port (24, 29) from each other is disposed in the high-pressure gas space (HS). The oil separation mechanism (82) does not need to be disposed outside the casing (16), suppressing the increase in the number of components and reducing damage to the flow path of the refrigerating machine oil due to vibration of the rotary compressor.

[0101] According to this embodiment, the oil separation mechanism (82) is disposed inside the casing (16), shortening the distance from the oil separation mechanism (82) to the oil reservoir (85). This eliminates the need for a pipe for delivering the refrigerating machine oil separated by the oil separation mechanism (82) to the oil reservoir (85). If the pipe for delivering the refrigerating machine oil is provided, the pipe can be shortened, suppressing the decrease in amount of oil supply to the vane chambers (48, 49).(8-2) Second Feature

[0102] In the rotary compressor (1) of this embodiment, the oil reservoir (85) is formed in the high-pressure gas space (HS). The rotary compressor (1) further includes the oil supply passage (90) that supplies the refrigerating machine oil in the oil reservoir (85) to the vane chamber (48, 49).

[0103] In this embodiment, the high-pressure gas space (HS) that supplies the refrigerating machine oil to the vane chamber (48, 49) is formed in the casing (16), shortening the oil supply passage (90) from the oil reservoir (85) to the vane chamber (48, 49). This can reduce the flow path resistance in the oil supply passage (90), suppressing a decrease in amount of oil supplied to the vane chamber (48, 49). If a pipe diameter of the oil supply passage (90) is increased to reduce the flow path resistance, the amount of oil required for filling the compressor increases, and the amount of refrigerant dissolved in the refrigerating machine oil also increases. However, the shortened oil supply passage (90) does not require the large pipe diameter, suppressing the increase in amount of oil and the amount of refrigerant filling the compressor.(8-3) Third Feature

[0104] The oil reservoir (85) of this embodiment is provided at the bottom of the high-pressure gas space (HS). The rotary compressor (1) includes the oil supply passage (90) that supplies the refrigerating machine oil from the oil reservoir (85) to each vane chamber (48, 49). The bottom of the high-pressure gas space (HS) has the tapered surface (81a) that is inclined downward toward the inlet end of the oil supply passage (90).

[0105] In this embodiment, the inlet of the oil supply passage (90) is disposed in the oil reservoir (85). The bottom surface of the oil reservoir (85) inclined toward the oil supply passage (90) causes the refrigerating machine oil to easily accumulate at the inlet of the oil supply passage (90). This allows the refrigerating machine oil in the oil reservoir (85) to flow easily into the oil supply passage (90).(8-4) Fourth Feature

[0106] The oil separation mechanism (82) of this embodiment is a mesh member that separates the refrigerant and the refrigerating machine oil from each other when the refrigerant gas passes through the mesh member. Simply providing the mesh member in the housing (81) allows separation of the refrigerant and the refrigerating machine oil with a relatively simple mechanism. This can reduce the cost of the oil separation mechanism (82).(8-5) Fifth Feature

[0107] The rotary compressor (1) of this embodiment includes the two-cylinder compression mechanism (15), and further includes the communication passage (91) provided in the compression mechanism (15) to allow the first discharge port (24) for discharging the refrigerant compressed in the first cylinder (30) and the second discharge port (29) for discharging the refrigerant compressed in the second cylinder (35) to communicate with each other. The communication passage (91) supplies the discharged refrigerant to the oil separation mechanism (82).

[0108] In this embodiment, the effects described above as the first and second features can be achieved with a single oil separation mechanism (82) by providing the communication passage (91) in the two-cylinder rotary compressor.(8-6) Sixth Feature

[0109] The refrigeration cycle apparatus (100) includes the rotary compressor of the present embodiment. The refrigeration cycle apparatus includes the rotary compressor (1) having the oil separation mechanism (82) inside the casing (16). This configuration does not require a space for placing the oil separator (80) in the refrigeration cycle apparatus (100), making the refrigeration cycle apparatus (100) compact.(9) Variations

[0110] Variations of the rotary compressor (1) of the above embodiment will be described below. Hereinafter, differences between the variations and the rotary compressor (1) of the above embodiment will be described.(9-1) First Variation

[0111] In a rotary compressor (1) of a first variation illustrated in FIGS. 5 and 6, the oil separation mechanism (82) is disposed in the rear muffler chamber (64). The discharge pipe (54) is provided to directly communicate with the rear muffler (63).

[0112] The discharge gas passage (91) extends from the front muffler chamber (62) to the rear muffler chamber (64) while penetrating the cylinders (30, 35) and the middle plate in the up-down direction. The high-pressure gas space (HS) includes the rear muffler chamber (64).

[0113] The oil separation mechanism (82) is disposed in the rear muffler chamber (64) (dotted region in FIG. 6). In the first variation, the refrigerant and the refrigerating machine oil are separated from each other in the rear muffler chamber (64). The oil reservoir (85) is formed in the rear muffler chamber (64). The refrigerating machine oil is stored in the rear muffler (63).

[0114] The oil supply passage (90) allows the rear muffler chamber (64) and each vane chamber (48, 49) to communicate with each other. The inlet (83) of the oil supply passage (90) is disposed in the oil reservoir (85) of the rear muffler chamber (64).

[0115] The high-pressure refrigerant discharged from the first discharge port (24) to the front muffler chamber (62) flows downward through the discharge gas passage (91) (as indicated by a broken arrow in FIG. 5), and merges with the high-pressure refrigerant discharged from the second discharge port (29) in the rear muffler chamber (64). In the rear muffler chamber (64), the oil separation mechanism (82) separates the refrigerant and the refrigerating machine oil from each other. The refrigerant gas flows into the discharge pipe (54) (as indicated by a broken arrow in FIG. 6), while the refrigerating machine oil stored in the oil reservoir (85) flows into the oil supply passage (90) (as indicated by a two-dot-dash arrow in FIG. 6). Thereafter, the refrigerating machine oil flows upward through the oil supply passage (90) (as indicated by the two-dot-dash arrow in FIG. 5), and is supplied to the first vane chamber (48) and the second vane chamber (49).

[0116] As described above, in the rotary compressor (1) of the first variation, the oil separation mechanism (82) is disposed in the rear muffler chamber (64), suppressing the interference, caused by the separated refrigerating machine oil, with the opening and closing of the discharge valve of the second discharge port (29). This can suppress the decrease in compression efficiency of the rotary compressor (1). Further, the rear muffler chamber (64) that also serves as the space for the oil separation mechanism (82) can reduce the amount of refrigerant filling the refrigerant circuit (9).(9-2) Second Variation

[0117] In a rotary compressor (1) of a second variation shown in FIGS. 7 and 8, the oil separation mechanism (82) is disposed in the front muffler chamber (62). The discharge pipe (54) is provided to directly communicate with the front muffler chamber (62).

[0118] The discharge gas passage (91) extends from the rear muffler chamber (64) to the front muffler chamber (62) while penetrating the cylinders (30, 35) and the middle plate in the up-down direction. The high-pressure gas space (HS) includes the front muffler chamber (62).

[0119] The oil separation mechanism (82) is disposed in the front muffler chamber (62). In the second variation, the refrigerant and the refrigerating machine oil are separated from each other in the front muffler chamber (62). The oil reservoir (85) is formed in the front muffler chamber (62).

[0120] The oil supply passage (90) allows the front muffler chamber (62) and each vane chamber (48, 49) to communicate with each other. The inlet (83) of the oil supply passage (90) is disposed in the oil reservoir (85) of the front muffler chamber (62).

[0121] The high-pressure refrigerant discharged from the first discharge port (24) and the high-pressure refrigerant discharged from the second discharge port (29) merge in the front muffler chamber (62). In the front muffler chamber (62), the oil separation mechanism (82) separates the refrigerant and the refrigerating machine oil from each other. The refrigerant gas flows into the discharge pipe (54), while the refrigerating machine oil is stored in the oil reservoir (85). The refrigerating machine oil in the oil reservoir (85) flows into the oil supply passage (90) and is supplied to the first vane chamber (48) and the second vane chamber (49) in this order.

[0122] As described above, in the second variation, the oil separation mechanism (82) is disposed in the front muffler chamber (62), and thus the separated refrigerating machine oil is easily supplied to the vane chambers (48, 49) by its own weight. This improves the efficiency of oil supply to the vane chambers (48, 49).(9-3) Third Variation

[0123] A rotary compressor (1) of a third variation differs from the rotary compressor (1) of the first variation in the arrangement of the oil separation mechanism (82). Specifically, as illustrated in FIGS. 9 and 10, the oil separation mechanism (82) is disposed inside the second cylinder (35). The discharge pipe (54) is provided to communicate with the rear muffler chamber (64).

[0124] The second cylinder (35) has a larger diameter than the first cylinder (30). The second cylinder (35) is thicker in the radial direction than the first cylinder (30). A high-pressure gas space (HS) is formed in the second cylinder (35). The high-pressure gas space (HS) is formed around the cylinder chamber (S1, S2). The high-pressure gas space (HS) is formed in an arc shape extending in the circumferential direction of the cylinder (30, 35). A gas inlet (83) communicating with the discharge gas passage (91) is formed near one end of the high-pressure gas space (HS). A gas outlet (84) communicating with the discharge pipe (54) connected to the rear head (25) is formed at the other end of the high-pressure gas space (HS). Thus, the gas inlet (83) is formed near one end of the arc-shaped high-pressure gas space (HS), the gas outlet (84) is formed at the other end, and the gas inlet (83) is disposed within a range of 90° to 150° from the gas outlet (84) in the circumferential direction of the casing (16) about the drive shaft (70).

[0125] The oil separation mechanism (82) is disposed in the high-pressure gas space (HS) of the second cylinder (35). The oil separation mechanism (82) extends in the longitudinal direction (circumferential direction) of the high-pressure gas space (HS). The oil supply passage (90) is formed at the other end of the high-pressure gas space (HS) and near the gas outlet (84). In the second cylinder (35), a portion of the oil supply passage (90) allows the high-pressure gas space (HS) to communicate with the second vane chamber (49).

[0126] The high-pressure refrigerant discharged from the first discharge port (24) and entered the front muffler chamber (62) flows through the discharge gas passage (91), and merges with the high-pressure refrigerant discharged from the second discharge port (29) in the rear muffler chamber. The merged high-pressure refrigerant flows into the high-pressure gas space (HS) and is separated into the refrigerant and the refrigerating machine oil. The refrigerant flows into the discharge pipe (54) through the gas outlet (84), and the refrigerating machine oil flows into the second vane chamber (49). Part of the refrigerating machine oil that entered the second vane chamber (49) flows toward the second bushings (47), and the rest of the refrigerating machine oil flows upward through the oil supply passage (90) to enter the first vane chamber (48). The refrigerating machine oil that entered the first vane chamber (48) is supplied to the first bushings (42).

[0127] The oil separation mechanism (82) provided in the cylinder (30, 35) in this manner can shorten the length of the oil supply passage (90) communicating with each vane chamber (48, 49).(9-4) Fourth Variation

[0128] A rotary compressor (1) of a fourth variation illustrated in FIGS. 11 and 12 has a high-pressure gas space (HS) in a space below the casing (16). The rotary compressor (1) has a partition plate (95) for separating the high-pressure gas space (HS). The partition plate (95) is disposed below the compression mechanism (15). The partition plate (95) is provided to close the upper end of the lower end plate (19). The high-pressure gas space (HS) is a space surrounded by the lower end plate (19) and the partition plate (95).

[0129] The discharge pipe (54) communicates with the high-pressure gas space (HS). The discharge pipe (54) is provided to penetrate a side portion of the lower end plate (19).

[0130] The discharge gas passage (91) is provided to extend from the front muffler chamber (62) to the high-pressure gas space (HS) and penetrate the first cylinder (30), the middle plate (50), the second cylinder (35), the rear head (25), the rear muffler (63), and the partition plate (95). The discharge gas passage (91) has a discharge gas pipe (91a) penetrating the rear muffler (63) and the partition plate (95).

[0131] The oil separation mechanism (82) is disposed in a space below the partition plate (95). The oil reservoir (85) is formed at the bottom of the casing (16).

[0132] The oil supply passage (90) includes a first flow path (90a) and a second flow path (90b). The first flow path (90a) and the second flow path (90b) are connected in order in a flow direction of the refrigerating machine oil. The first flow path (90a) is provided outside the casing (16). An inlet end of the first flow path (90a) is connected to the lower end plate (19). An inlet of the first flow path (90a) is connected to the lowest part of the oil reservoir (85). An outlet end of the first flow path (90a) extends radially from the outside to the inside through the barrel (17), and is connected to the rear head (25). The second flow path (90b) is formed to penetrate the rear head (25), the second cylinder (35), the middle plate (50), and the first cylinder (30) in the up-down direction. The second flow path (90b) communicates with the first vane chamber (48) and the second vane chamber (49).

[0133] The high-pressure refrigerant discharged from the first discharge port (24) and the second discharge port (29) flows into the high-pressure gas space (HS) through the discharge gas passage (91). In the high-pressure gas space (HS), the oil separation mechanism (82) separates the refrigerant and the refrigerating machine oil from each other. The refrigerant gas flows into the discharge pipe (54), while the refrigerating machine oil is stored in the oil reservoir (85). The refrigerating machine oil in the oil reservoir (85) flows into the first flow path (90a), and then flows from the first flow path (90a) to the rear head (25). The refrigerating machine oil flowed into the rear head (25) goes up in the second flow path (90b). At this time, the refrigerating machine oil is supplied to the second vane chamber (49) and the first vane chamber (48) in this order.

[0134] As described above, in the fourth variation, the compressor (1) is formed into a high-low pressure dome, and the oil separator (80) is disposed in the high-pressure gas space (HS). This can reduce the leakage of the refrigerant gas from the high-pressure gas space (HS) to the low-pressure space. Further, providing the oil supply passage (90) outside the casing (16) increases installation flexibility of the compressor (1).(9-5) Fifth Variation

[0135] A rotary compressor (1) of a fifth variation illustrated in FIG. 13 is different from the rotary compressor (1) of the fourth variation only in the configuration of the oil supply passage (90). The first flow path (90a) of the oil supply passage (90) of the fifth variation is provided inside the casing (16). The first flow path (90a) is provided to penetrate the partition plate (95) and the rear muffler (63). In the fifth variation, the oil supply passage (90) is provided to penetrate the partition plate (95), reducing the length of the oil supply passage (90).(10) Other Embodiments

[0136] The rotary compressors (1) of the above embodiment and variations may be configured as follows.

[0137] The oil separation mechanism (82) of the third variation may be provided inside the first cylinder (30) or the middle plate (50). When the oil separation mechanism (82) is provided in the first cylinder (30), the discharge pipe (54) is connected to the first cylinder (30). When the oil separation mechanism (82) is provided in the middle plate (50), the discharge pipe (54) is connected to the middle plate (50). The oil separation mechanism (82) disposed in the middle plate (50) can suppress the decrease in amount of the refrigerating machine oil supplied to the vane chambers (48, 49) of the cylinders adjacent to each other in the up-down direction (the first cylinder (30) and the second cylinder (35)).

[0138] The oil separation mechanism (82) of the third variation may be provided to penetrate the first cylinder (30), the middle plate (50), and the second cylinder (35). In this case, a space penetrating the first cylinder (30), the middle plate (50), and the second cylinder (35) in the up-down direction is formed. The oil separation mechanism (82) is disposed in this space. Thus, the space for placing the oil separation mechanism (82) is vertically elongated, and thus, a sufficient amount of refrigerating machine oil can be stored in a lower portion of the space.

[0139] In the above embodiment and variations, the oil separation mechanism (82) may simply be disposed in the high-pressure gas space (HS). For example, the high-pressure gas space (HS) may be provided inside the front muffler (61) or the rear muffler (63). In this case, the oil separation mechanism (82) is provided inside the front muffler (61) or the rear muffler (63). This space functions as a high-pressure gas space. For example, the high-pressure refrigerant discharged into the front muffler chamber (62) from the first discharge port (24) flows into the oil separation mechanism (82) provided inside the front muffler (61), and is separated into the refrigerant and the refrigerating machine oil. The oil separation mechanism (82) may be provided in both the front muffler (61) and the rear muffler (63).

[0140] In the high-pressure gas space (HS) of the rotary compressor (1) of the third variation, the gas inlet (83) through which the discharge gas flows may be disposed within a range of 90° to 270° from the gas outlet (84) through which the discharge gas flows out in the circumferential direction of the casing (16) about the drive shaft (70). This arrangement of the gas outlet (84) and the gas inlet (83) is not limited to the third variation, and may be applied to the high-pressure gas space (HS) of each of the above embodiment and variations. The high-pressure gas space (HS) formed in this manner can increase the distance from the gas inlet (83) to the gas outlet (84). This can increase the length of the refrigerant flow path in the oil separation mechanism (82) disposed in the high-pressure gas space (HS), separating more oil from the refrigerant.

[0141] In the fifth variation, the discharge gas passage (91) may be disposed outside the casing (16). In this case, the discharge gas passage (91) allows the high-pressure gas space (HS) separated by the partition plate to communicate with the front muffler chamber (62) and the rear muffler chamber (64). This can reduce the distance between the oil separation mechanism (82) and the vane chambers (48, 49), allowing easy supply of the refrigerating machine oil to the vane chambers (48, 49). Further, the discharge gas passage (91) disposed outside the casing (16) improves the installation flexibility of the discharge gas passage (91).

[0142] In the fourth or fifth variation, the rotary compressor (1) may include the compression mechanism (15) disposed above the electric motor (10). In this case, the high-pressure gas space (HS) is formed above the first space (Si). Thus, the separated refrigerating machine oil can be easily supplied to each vane chamber (48, 49) by its own weight.

[0143] In the above embodiment and variations, the compression mechanism (15) of the rotary compressor (1) may be a single-cylinder rotary compressor. In this case, the muffler (61, 63) may be either one of the front muffler (61) or the rear muffler (63). In the above embodiment and variations, the muffler (61, 63) of the compression mechanism (15) may be either one of the front muffler (61) or the rear muffler (63) as long as the oil separation mechanism (82) of the present disclosure can be installed.

[0144] In the above embodiment and variations, the rotary compressor (1) may be a horizontal rotary compressor.

[0145] In the above embodiment and variations, the rotary compressor (1) may include an oil return passage (not shown) for returning an excess amount of the refrigerating machine oil supplied to each vane chamber (48, 49) to the oil reservoir (85).

[0146] In the above embodiment and variations, the oil separation mechanism (82) may be any mechanism, for example, a porous member, as long as it allows the refrigerant gas to pass through and separates the refrigerating machine oil from the refrigerant gas. As illustrated in FIG. 14, the oil separation mechanism (82) may be a plate member (96) provided in the housing (81). The plate member (96) separates the refrigerant and the refrigerating machine oil when the refrigerant gas collides against the plate member (96). Specifically, the plate member (96) is provided so that the refrigerant gas does not flow linearly from the gas inlet (83) to the gas outlet (84) formed in the housing (81). More specifically, two or more plate members (96) are provided to block the refrigerant gas flowing straight from the gas inlet (83) toward the gas outlet (84). In the example shown in FIG. 14, the plate members (96) are connected to the inner surfaces of the housing (81) facing each other. The plate members (96) are arranged so that the refrigerant gas flows in a zigzag manner from the gas inlet (83) toward the gas outlet (84). This causes the refrigerant gas to meander in the housing (81), allowing easy separation of the refrigerating machine oil from the refrigerant gas by centrifugation. Further, the refrigerant gas flows toward the gas outlet (84) while colliding against the plate members (96), allowing easy separation of the refrigerating machine oil from the refrigerant gas by the collision.

[0147] In the above embodiment and variations, the rotary compressor (1) may have no introduction pipe (55). In this case, the compression mechanism (15) has a refrigerant passage (not shown) that allows the first space (Si) and each cylinder (30, 35) to communicate with each other. Specifically, the refrigerant passage is formed such that the refrigerant flows from a suction hole (not shown) provided in the front head (20) toward the suction port (33, 38) of each cylinder (30, 35). Thus, the low-pressure refrigerant in the first space (Si) is sucked into the compression mechanisms (K1, K2) through the refrigerant passage and compressed. The compressed refrigerant is discharged from the rear head (25). The oil separation mechanism (82) of any of the above embodiment and variations is employed.

[0148] In the above embodiment and variations, the oil separation mechanism may be a cyclone or helical oil separation mechanism. In this case, the refrigerating machine oil is separated from the refrigerant by centrifugal force.

[0149] In each of the above variations, if the oil reservoir (85) is formed at the bottom of the casing (16), the oil reservoir (85) may also serve as a reservoir for storing the refrigerating machine oil to be supplied to the compression mechanism (15).

[0150] Any of the rotary compressors (1) of the above embodiment and variations may have the tapered surface (81a). The rotary compressor may further include the housing (81) having the oil separation mechanism (82).

[0151] While the embodiments and variations thereof have been described above, it will be understood that various changes in form and details may be made without departing from the spirit and scope of the claims. The foregoing embodiments and variations thereof may be combined and replaced with each other without deteriorating the intended functions of the present disclosure. The expressions of "first," "second," ... described above are used to distinguish the terms to which these expressions are given, and do not limit the number and order of the terms.INDUSTRIAL APPLICABILITY

[0152] As described above, the present disclosure is useful for a rotary compressor.DESCRIPTION OF REFERENCE CHARACTERS

[0153] 1Rotary Compressor (Compressor) 10Electric Motor 15Compression Mechanism 16Casing 20Front Head (First End Plate) 24First Discharge Port 24, 29Discharge Port 25Rear Head (Second End Plate) 29Second Discharge Port 30First Cylinder 30, 35Cylinder 35Second Cylinder 40, 45Rotor 41, 46Vane 48, 49Vane Chamber 50Middle Plate 61, 63Muffler 62, 64Muffler Chamber 70Drive Shaft 81aTapered Surface 82Oil Separation Mechanism 83Gas Inlet (Inlet) 84Gas Outlet (Outlet) 90Oil Supply Passage 91Discharge Gas Passage (Communication Passage) 96Plate Member 100Refrigeration Cycle Apparatus HSHigh-Pressure Gas Space S1, S2Cylinder Chamber SdDischarge Space SiFirst Space SsSuction Space

Claims

1. A rotary compressor (1), comprising: a casing (16) configured to form a first space (Si) in which a refrigerant at a suction pressure flows; an electric motor (10) disposed in the first space (Si); a drive shaft (70) configured to be rotated by the electric motor (10) about its axis; and a compression mechanism (15) configured to be driven by the drive shaft (70) to compress the refrigerant in the first space (Si) and discharge the compressed refrigerant from a discharge port (24, 29), wherein the compression mechanism (15) includes a cylinder (30, 35), a roller (40, 45) configured to rotate eccentrically in a space surrounded by an inner wall of the cylinder (30, 35), a vane (41, 46) configured to be inserted into a vane chamber (48, 49) formed inside the cylinder (30, 35) and partition a cylinder chamber (S1, S2) formed by the space surrounded by the inner wall of the cylinder (30, 35) and the roller (40, 45) into a suction space (Ss) and a discharge space (Sd), a first end plate (20) configured to close one axial end of the cylinder (30, 35), and a second end plate (25) configured to close the other axial end of the cylinder (30, 35), the casing (16) forms an oil reservoir (85) configured to store refrigerating machine oil and a high-pressure gas space (HS) into which the refrigerant discharged from the discharge port (24, 29) flows and which communicates with the vane chamber (48, 49), and an oil separation mechanism (82) configured to separate the refrigerant and the refrigerating machine oil discharged from the discharge port (24, 29) from each other is disposed in the high-pressure gas space (HS).

2. The rotary compressor of claim 1, wherein the oil reservoir (85) is formed in the high-pressure gas space (HS), and the rotary compressor further includes an oil supply passage (90) configured to supply the refrigerating machine oil in the oil reservoir (85) to the vane chamber (48, 49).

3. The rotary compressor of claim 1 or 2, further comprising: an inlet (83) through which the refrigerant compressed by the compression mechanism (15) flows into the high-pressure gas space (HS); and an outlet (84) through which the refrigerant in the high-pressure gas space (HS) flows out of the high-pressure gas space (HS), wherein the inlet (83) is disposed within a range of 90° to 270° from the outlet (84) in a circumferential direction of the casing (16) about the drive shaft (70).

4. The rotary compressor of any one of claims 1 to 3, wherein the oil reservoir (85) is provided at the bottom of the high-pressure gas space (HS), the rotary compressor further includes an oil supply passage (90) that supplies the refrigerating machine oil in the oil reservoir (85) to the vane chamber (48, 49), and a bottom of the high-pressure gas space (HS) has a tapered surface (81a) that is inclined downward toward the oil supply passage (90).

5. The rotary compressor of any one of claims 1 to 4, further comprising: a muffler (61, 63) that forms a muffler chamber (62, 64) when the refrigerant discharged from the discharge port (24, 29) flows in, wherein the oil separation mechanism (82) is disposed inside the muffler chamber (62, 64) or the muffler (61, 63).

6. The rotary compressor of any one of claims 1 to 4, wherein the oil separation mechanism (82) is provided inside the cylinder (30, 35).

7. The rotary compressor of any one of claims 1 to 6, wherein the oil separation mechanism (82) includes: a mesh member that separates the refrigerant and the refrigerating machine oil from each other when a refrigerant gas passes through the mesh member or a plate member (96) that separates the refrigerant and the refrigerating machine oil from each other when the refrigerant gas collides against the plate member (96).

8. The rotary compressor of any one of claims 1 to 7, wherein the compression mechanism (15) is a two-cylinder compression mechanism, and the compression mechanism (15) includes a first cylinder (30) and a second cylinder (35) arranged in an axial direction and a middle plate (50) disposed between the first cylinder (30) and the second cylinder (35), the rotary compressor further includes a communication passage (91) provided in the compression mechanism (15) to allow a first discharge port (24) for discharging the refrigerant compressed in the first cylinder (30) and a second discharge port (29) for discharging the refrigerant compressed in the second cylinder (35) to communicate with each other, and the communication passage (91) supplies the discharged refrigerant to the oil separation mechanism (82).

9. A refrigeration cycle apparatus comprising the rotary compressor of any one of claims 1 to 8.

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