Rotary compressor and refrigeration system equipped therewith

Abstract

This suppresses the delayed closing of the reed valve when the refrigerant pressure in the cylinder chamber exceeds the intermediate pressure. [Solution] The first cylinder (31) is provided with a first valve housing (31j) that is recessed from the inner circumferential surface toward the outside and houses a first reed valve (63) and a first valve retainer (64). The first reed valve (63) is fixed to the valve mounting surface (31g) of the first valve housing (31j) radially outward from the first injection opening (31b) of the first cylinder (31). The first valve retainer (64) has a valve retainer passage (P1) formed between a first surface of the first valve retainer (64) facing the first reed valve (63) and a second surface facing the first cylinder chamber (S1).

Description

Technical Field

[0001] The present disclosure relates to a rotary compressor and a refrigeration apparatus including the same. The rotary compressor 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. The rotary compressor includes a so-called rolling piston type in which a vane separate from the roller abuts against the roller while the roller rotates eccentrically, a so-called swing type in which a vane formed integrally with the roller swings as the roller rotates eccentrically, a so-called hinge vane type in which the tip of the vane is rotatably fitted into a recess on the outer peripheral surface of the roller and the roller rotates eccentrically, and the like.

Background Art

[0002] Patent Document 1 discloses a rotary compressor having an injection passage. In the cylinder of this rotary compressor, a valve housing portion recessed outward from the inner peripheral surface on the cylinder chamber side is provided. A reed valve is housed in a portion of the valve housing portion excluding the end on the cylinder chamber side. An injection opening opened and closed by the reed valve is provided on the valve mounting surface of the valve housing portion.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in the above Patent Document 1, when the pressure of the refrigerant in the cylinder chamber becomes higher than the intermediate pressure, refrigerant flows from the cylinder chamber between the reed valve and the valve mounting surface, and there is a problem that the closing delay of the reed valve is likely to occur.

[0005] The purpose of this disclosure is to suppress the delayed closing of the reed valve when the refrigerant pressure in the cylinder chamber becomes higher than the intermediate pressure. [Means for solving the problem]

[0006] A first aspect of the technology disclosed herein is a rotary compressor having an injection passage (61), comprising: pistons (34, 44); a drive shaft (90) for driving the pistons (34, 44); a first bearing (56) and a second bearing (50) for supporting the drive shaft (90); cylinders (31, 41) in which the pistons (34, 44) are housed and which have cylinder chambers (S1, S2) partitioned by their inner surfaces; reed valves (63, 66) disposed in the injection passage (61); and valve retainers (64, 67) disposed opposite the reed valves (63, 66), wherein the cylinders (31, 41) have valve recesses that are recessed outward from the inner surface and house the reed valves (63, 66) and the valve retainers (64, 67). A valve housing portion (31j, 41j) is provided, and an injection opening (31b, 41b) is provided on the valve mounting surface (31g, 41g), which is the surface of the valve housing portion (31j, 41j) on the first bearing (56) side or the second bearing (50) side, which is opened and closed by the reed valve (63, 66). The reed valve (63, 66) is fixed to the valve mounting surface (31g, 41g) of the valve housing portion (31j, 41j) radially outward from the injection opening (31b, 41b) of the cylinder (31, 41). The valve retainer (64, 67) has a valve retainer passage (P1) formed between the first surface of the valve retainer (64, 67) facing the reed valve (63, 66) and the second surface facing the cylinder chamber (S1, S2).

[0007] In the first embodiment, when the refrigerant pressure in the cylinder chambers (S1, S2) becomes higher than the intermediate pressure, the refrigerant flows from the cylinder chambers (S1, S2) through the valve retainer passage (P1) between the reed valves (63, 66) and the valve retainers (64, 67). Therefore, the pressure from the valve retainer (64, 67) side acting on the reed valves (63, 66) can be increased, and the delay in closing the reed valves (63, 66) can be suppressed.

[0008] A second aspect of the technology disclosed herein is that, in the first aspect, during the process of moving the reed valves (63, 66) from an open state to a closed state, a refrigerant flow path (P2) communicating with the cylinder chambers (S1, S2) is formed between the valve retainers (64, 67) and the reed valves (63, 66), separately from the valve retainer flow path (P1).

[0009] In the second embodiment, when the refrigerant pressure in the cylinder chambers (S1, S2) becomes higher than the intermediate pressure, the refrigerant from the cylinder chambers (S1, S2) flows between the reed valves (63, 66) and the valve retainers (64, 67) via both the valve retainer passage (P1) and the refrigerant passage (P2). Therefore, the pressure from the valve retainer (64, 67) side acting on the reed valves (63, 66) can be increased, and the delay in closing the reed valves (63, 66) can be suppressed more effectively.

[0010] A third aspect of the technology disclosed herein is that, in the first or second aspect, the longitudinally extending centerlines (C1, C2) of the reed valves (63, 66) coincide with the openings of the valve housing (31j, 41j) on the cylinder chamber (S1, S2) side.

[0011] In the third embodiment, the refrigerant pressure from the cylinder chambers (S1, S2) acts more evenly on both sides of the centerlines (C1, C2) of the reed valves (63, 66) compared to the case where the centerlines (C1, C2) extending in the longitudinal direction of the reed valves (63, 66) do not coincide with the openings of the valve housing (31j, 41j) on the cylinder chamber (S1, S2) side. Therefore, it is possible to suppress the reed valves (63, 66) from cracking due to the refrigerant pressure from the cylinder chambers (S1, S2).

[0012] A fourth aspect of the technology disclosed herein is, in the first or third aspect, a first valve retainer groove (64f) having a groove opening (64g) on ​​the cylinder chamber (S1, S2) side is formed on the first surface of the valve retainer (64, 67), and the first valve retainer groove (64f) constitutes the valve retainer passage (P1).

[0013] A fifth aspect of the technology disclosed herein is, in the fourth aspect, that the longitudinally extending centerlines (C1, C2) of the reed valves (63, 66) coincide with the groove opening (64g) of the first valve retaining groove (64f).

[0014] In the fifth embodiment, the refrigerant pressure from the cylinder chambers (S1, S2) acts in a more balanced manner on both sides of the centerline (C1, C2) of the reed valve (63, 66) compared to the case where the groove opening (64g) of the first valve retaining groove (64f) does not coincide with the centerline (C1, C2) extending in the longitudinal direction of the reed valve (63, 66). Therefore, it is possible to suppress the reed valve (63, 66) from cracking due to the refrigerant pressure from the cylinder chambers (S1, S2).

[0015] A sixth aspect of the technology disclosed herein is that, in any one of the first to third aspects, the valve retainer (64, 67) has a second valve retainer groove (64b) extending along a third surface opposite to the first surface and having a groove opening (64c) on the cylinder chamber (S1, S2) side, and a communication hole (64d) having a hole opening (64e) on the first surface and connecting the second valve retainer groove (64b) and the valve housing (31j, 41j), wherein the second valve retainer groove (64b) and the communication hole (64d) constitute the valve retainer flow path (P1).

[0016] A seventh aspect of the technology disclosed herein is, in the sixth aspect, the centerline (CH) of the communication hole (64d) intersects with the centerlines (C1, C2) extending longitudinally of the reed valves (63, 66).

[0017] In the seventh embodiment, the refrigerant pressure from the cylinder chambers (S1, S2) acts in a more balanced manner on both sides of the centerline (C1, C2) of the centerline (C1, C2) of the reed valves (63, 66), compared to the case where the centerline (CH) of the communication hole (64d) does not intersect with the centerlines (C1, C2) extending in the longitudinal direction of the reed valves (63, 66). Therefore, it is possible to suppress the reed valves (63, 66) from cracking due to the refrigerant pressure from the cylinder chambers (S1, S2).

[0018] An eighth aspect of the technology disclosed herein is, in the seventh aspect, the longitudinally extending centerlines (C1, C2) of the reed valves (63, 66) coincide with the groove opening (64c) of the second valve retaining groove (64b).

[0019] In the eighth aspect, the refrigerant pressure from the cylinder chambers (S1, S2) acts more evenly on both sides of the centerline (C1, C2) of the reed valve (63, 66) compared to the case where the groove opening (64c) of the second valve retaining groove (64b) does not coincide with the centerline (C1, C2) extending in the longitudinal direction of the reed valve (63, 66). Therefore, it is possible to suppress the reed valve (63, 66) from cracking due to the refrigerant pressure from the cylinder chambers (S1, S2).

[0020] A ninth aspect of the technology disclosed herein is that, in any one of the sixth to eighth aspects, at least a portion of the opening (64e) of the communication hole (64d) of the valve retainer (64, 67) overlaps with the injection opening (31b, 41b) and the reed valve (63, 66) in the opening and closing direction.

[0021] A tenth aspect of the technology disclosed herein is, in the ninth aspect, an annular valve seat (31i) is provided protruding from the outer peripheral edge of the injection opening (31b, 41b) of the cylinder (31, 41), and the opening (64e) of the communication hole (64d) of the valve retainer (64, 67) overlaps with the region inside the outer peripheral edge of the valve seat (31i) and the opening and closing direction of the reed valve (63, 66) over the entire length.

[0022] In the tenth embodiment, when the refrigerant pressure in the cylinder chambers (S1, S2) becomes higher than the intermediate pressure, the pressure of the refrigerant flowing out from the opening (64e) of the communication hole (64d) can cause the reed valves (63, 66) to partially contact the valve seat (31i), thereby preventing them from cracking due to the resulting stress.

[0023] The eleventh aspect of the technology disclosed herein is that, in any one of the sixth to tenth aspects, in the process of closing the reed valves (63, 66) from the open state to the closed state, a refrigerant flow path (P2) communicating with the cylinder chambers (S1, S2) is formed between the valve retainers (64, 67) and the reed valves (63, 66), and the hydraulic diameter of the valve retainer flow path (P1) is larger than the hydraulic diameter of the refrigerant flow path (P2).

[0024] In the eleventh aspect, when the pressure of the refrigerant in the cylinder chambers (S1, S2) becomes higher than the intermediate pressure, the refrigerant from the cylinder chambers (S1, S2) easily flows through the valve retainer flow path (P1).

[0025] The twelfth aspect of the technology disclosed herein is that, in any one of the first to eleventh aspects, the refrigerant is CO2.

[0026] In the twelfth aspect, since CO2 with a relatively high pressure is used as the refrigerant, when the refrigerant flows from the cylinder chambers (S1, S2) between the reed valves (63, 66) and the valve mounting surfaces (31g, 41g), the closing delay of the reed valves (63, 66) tends to increase. However, by flowing the refrigerant from the cylinder chambers (S1, S2) between the reed valves (63, 66) and the valve retainers (64, 67) through the valve retainer flow path (P1), the closing delay of the reed valves (63, 66) can be suppressed.

[0027] The thirteenth aspect of the technology disclosed herein is directed to a refrigeration device (100). The refrigeration device (100) includes the rotary compressor (1) described in any one of the first to twelfth aspects.

Brief Description of the Drawings

[0028] [Figure 1] FIG. 1 is a piping system diagram of a refrigeration device including the rotary compressor according to Embodiment 1. [Figure 2] FIG. 2 is a plan view of the rotary compressor. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III of FIG. 2. [Figure 4]Figure 4 is a cross-sectional view along the line IV-IV in Figure 7. [Figure 5] Figure 5 is a cross-sectional view along the VV line in Figure 7. [Figure 6] Figure 6 is a cross-sectional view along the line VI-VI in Figure 2. [Figure 7] Figure 7 is an enlarged view of section VII of Figure 6. [Figure 8] Figure 8 is a partial cross-sectional view along the line VIII-VIII in Figure 2. [Figure 9] Figure 9 is a schematic bottom view of the first cylinder. [Figure 10] Figure 10 is an enlarged view of section X in Figure 9. [Figure 11] Figure 11 is a perspective view of the first valve retainer. [Figure 12] Figure 12 is a cross-sectional view along the line XII-XII in Figure 10. [Figure 13] Figure 13 is a plan view of the first valve retainer around the first cylinder chamber side end. [Figure 14] Figure 14 shows the operation of the compression mechanism. [Figure 15] Figure 15 is a diagram corresponding to Figure 12 of Embodiment 2. [Figure 16] Figure 16 is a diagram corresponding to Figure 13 of Embodiment 2. [Modes for carrying out the invention]

[0029] Embodiments of this disclosure will be described in detail below with reference to the drawings. This disclosure is not limited to the embodiments shown below, and various modifications are possible without departing from the technical idea of ​​this disclosure. Since the drawings are for conceptual explanation of this disclosure, dimensions, ratios, or numbers may be exaggerated or simplified as necessary for ease of understanding. In the following description, unless otherwise specified, "axial direction" refers to the direction in which the shaft extends, "radial direction" refers to the direction radiating from the shaft, and "circumferential direction" refers to the circumferential direction centered on the shaft. Also, "up" and "down" indicate the direction when the rotary compressor (1) is viewed from the front. Furthermore, hatching may be omitted in the drawings to facilitate understanding of the explanation.

[0030] (1) Refrigeration equipment Figure 1 shows a refrigeration system (100) equipped with a rotary compressor (1) according to this first embodiment. Hereinafter, the rotary compressor (1) may be simply referred to as the compressor (1). The refrigeration system (100) is, for example, an air conditioning system that provides air conditioning for a room. The refrigeration system (100) has an outdoor unit (7) located outside and an indoor unit (8) located inside. The outdoor unit (7) is equipped with a compressor (1), an accumulator (2), a four-way switching valve (3), an outdoor heat exchanger (4a), an economizer heat exchanger (4b), and an expansion valve (5). The indoor unit (8) is equipped with an indoor heat exchanger (6). The outdoor unit (7) and the indoor unit (8) are connected via a connecting pipe (9a) to form a refrigerant circuit (9).

[0031] The compressor (1) compresses low-pressure gaseous refrigerant into high-pressure gaseous refrigerant. The compressor (1) is driven by a compressor motor. A portion of the intermediate-pressure refrigerant flowing from the outdoor heat exchanger (4a) toward the expansion valve (5) is supplied to the compressor (1), and intermediate injection is performed. The intermediate pressure is a predetermined pressure between the pressure of the gaseous refrigerant drawn into the compressor (1) (low pressure) and the pressure of the gaseous refrigerant discharged from the compressor (1) (high pressure). The refrigerant is not particularly limited, but for example, carbon dioxide (CO2).

[0032] The four-way directional valve (3) switches the connection state of the internal piping of the outdoor unit (7). When the refrigeration unit (100) is operating in cooling mode, the four-way directional valve (3) is in the connection state shown by the dashed line in Figure 1. When the refrigeration unit (100) is operating in heating mode, the four-way directional valve (3) is in the connection state shown by the solid line in Figure 1.

[0033] The outdoor heat exchanger (4a) exchanges heat between the refrigerant circulating in the refrigerant circuit (9) and the outdoor air. The outdoor heat exchanger (4a) has a refrigerant flow path through which the refrigerant flows and heat transfer fins that come into contact with the outdoor air. During cooling operation, the outdoor heat exchanger (4a) functions as a refrigerant radiator (condenser), and during heating operation, it functions as a refrigerant absorber (evaporator).

[0034] The expansion valve (5) is an electrically operated valve or solenoid valve with adjustable opening. The expansion valve (5) reduces the pressure of the refrigerant flowing through the internal piping of the outdoor unit (7). The expansion valve (5) controls the flow rate of the refrigerant flowing through the internal piping of the outdoor unit (7).

[0035] The accumulator (2) is located in the piping on the suction side of the compressor (1). The accumulator (2) separates the gas-liquid mixed refrigerant flowing through the refrigerant circuit into gaseous refrigerant and liquid refrigerant, and stores the liquid refrigerant. The gaseous refrigerant separated by the accumulator (2) is sent to the suction port of the compressor (1).

[0036] The economizer heat exchanger (4b) is positioned between the outdoor heat exchanger (4a) and the expansion valve (5). The economizer heat exchanger (4b) performs heat exchange between the refrigerant flowing from the outdoor heat exchanger (4a) toward the expansion valve (5) and the refrigerant flowing through the economizer piping (9b). The economizer piping (9b) is a pipe that branches off from the refrigerant circuit (9) between the economizer heat exchanger (4b) and the expansion valve (5) and is connected to the injection pipe (9c) (described later). An economizer valve (9d) is attached to the economizer piping (9b). The refrigerant flowing through the economizer piping (9b) is depressurized by the economizer valve (9d) and then exchanges heat with the refrigerant flowing from the outdoor heat exchanger (4a) toward the expansion valve (5) in the economizer heat exchanger (4b). The refrigerant flowing from the outdoor heat exchanger (4a) toward the expansion valve (5) and the refrigerant that has undergone heat exchange in the economizer heat exchanger (4b) are supplied to the injection pipe (9c) as refrigerant at an intermediate pressure.

[0037] The refrigeration system (100) includes a refrigerant circuit (9). A compressor (1), a four-way switching valve (3), an outdoor heat exchanger (4a), an expansion valve (5), an indoor heat exchanger (6), and an economizer heat exchanger (4b) are connected to the refrigerant circuit (9). The refrigeration cycle is performed by the flow of refrigerant through the refrigerant circuit (9).

[0038] The refrigeration system (100) performs heating and cooling operations by switching the four-way switching valve (3). In cooling operation, the first refrigeration cycle is performed. Specifically, in the connection state shown by the dashed line in Figure 1, the indoor heat exchanger (6) functions as an evaporator and the outdoor heat exchanger (4a) functions as a radiator. In heating operation, the second refrigeration cycle is performed. Specifically, in the connection state shown by the solid line in Figure 1, the indoor heat exchanger (6) functions as a radiator and the outdoor heat exchanger (4a) functions as an evaporator.

[0039] (2) Rotary compressor Figures 2 to 8 show the compressor (1). In particular, as shown in Figures 3 and 6, the compressor (1) comprises a casing (10), an electric motor (20), and a compression mechanism (30). The electric motor (20) and the compression mechanism (30) are housed within the casing (10). The compressor (1) is configured as a so-called high-pressure dome type, in which the refrigerant compressed in the compression mechanism (30) is discharged into the internal space (R) of the casing (10), and the internal space (R) becomes high-pressure.

[0040] (2-1) Rotary Compressor The casing (10) is formed in an elongated shape. Specifically, the casing (10) comprises a cylindrical body (11) extending in the vertical direction, an upper lid (12) that closes the upper end of the body (11), and a lower lid (13) that closes the lower end of the body (11). A discharge pipe (15) is inserted through the upper part of the body (11). A suction pipe (14) is located at the lower part of the body (11).

[0041] (2-2) Electric motor The electric motor (20) is housed in the casing (10). The electric motor (20) drives the compression mechanism (30). The electric motor (20) is positioned above the mounting plate (54). The electric motor (20) has a cylindrical stator (21) along the inner circumferential surface of the body (11) and a rotor (22) positioned inside the stator (21).

[0042] (2-3) Shaft The shaft (90) is positioned to extend vertically within the casing (10). That is, the axial direction of the shaft (90) is vertical. The shaft (90) is driven by the electric motor (20). The upper part of the shaft (90) is connected to the rotor (22) of the electric motor (20). The shaft (90) drives the first piston (34) and the second piston (44).

[0043] The lower part of the shaft (90) has, from top to bottom, an upper shaft portion (90a), a first eccentric portion (91), an intermediate shaft portion (90b), a second eccentric portion (92), and a lower shaft portion (90c). The upper shaft portion (90a), the first eccentric portion (91), the intermediate shaft portion (90b), the second eccentric portion (92), and the lower shaft portion (90c) are integrally formed with respect to each other.

[0044] The first eccentric portion (91) and the second eccentric portion (92) are eccentric with respect to the axis of the shaft (90). The first eccentric portion (91) and the second eccentric portion (92) are formed with a larger diameter than the upper shaft portion (90a), the intermediate shaft portion (90b), and the lower shaft portion (90c). The eccentric direction of the first eccentric portion (91) with respect to the rotational axis of the shaft (90) is 180° different from the eccentric direction of the second eccentric portion (92) with respect to the rotational axis of the shaft (90).

[0045] The intermediate shaft portion (90b) is positioned between the first eccentric portion (91) and the second eccentric portion (92). The intermediate shaft portion (90b) connects the first eccentric portion (91) and the second eccentric portion (92).

[0046] (2-4) Compression mechanism The compression mechanism (30) is located inside the casing (10). The compression mechanism (30) compresses the inhaled refrigerant and discharges it into the internal space (R) of the casing (10). The compression mechanism (30) is fixed to a mounting plate (54) which is fixed to the inner circumferential surface of the body (11). Specifically, the compression mechanism (30) is located on the lower surface of the mounting plate (54). The compression mechanism (30) has two cylinders. The compression mechanism (30) comprises a shaft (90) as a drive shaft, a front head (50) as an upper bearing (second bearing), a first cylinder (31), a first piston (34), a middle plate (55), a second cylinder (41), a second piston (44), and a rear head (56) as a lower bearing (first bearing).

[0047] As shown in Figures 6 and 7, injection passages (61) are formed in the first cylinder (31), middle plate (55), second cylinder (41), and rear head (56). The injection passages (61) communicate with the injection pipe (9c). An injection muffler (80) is connected to the injection pipe (9c), as shown in Figure 6. The lower end of the injection muffler (80) is located below the lower end of the front head (50).

[0048] As shown in an enlarged view in Figure 7, the injection passage (61) has a first passage (61a) connected to the injection tube (9c), a second passage (61b) branching off from the first passage (61a) and communicating with the first cylinder chamber (S1) (described later), and a third passage (61c) branching off from the first passage (61a) and communicating with the second cylinder chamber (S2) (described later). The injection tube (9c) is connected to the first passage (61a) by being inserted from the radially outer side. The second passage (61b) has a fourth passage (61d) that extends in the axial direction of the shaft (90) and penetrates the middle plate (55).

[0049] (2-4-1) Cylinder Figures 9 and 10 show the first cylinder (31). The first cylinder (31) and the second cylinder (41) are thick-walled disc-shaped members. Both cylinders (31, 41) have cylinder bores (32, 42) formed in them, particularly as shown in Figures 4 and 5. The cylinder bores (32, 42) are circular holes that penetrate in the thickness direction. The cylinder bores (32, 42) are formed in the central part of the cylinders (31, 41). The first piston (34) is housed in the cylinder bore (32) of the first cylinder (31). The second piston (44) is housed in the cylinder bore (42) of the second cylinder (41).

[0050] The first cylinder (31) has a first cylinder chamber (S1) that is partitioned by its inner circumferential surface. The second cylinder (41) has a second cylinder chamber (S2) that is partitioned by its inner circumferential surface.

[0051] Each cylinder (31, 41) has a vane housing hole (33, 43) formed therein, which extends radially outward from the inner circumferential surface of the cylinder (31, 41) (i.e., the outer edge of the cylinder bore (32, 42)). This vane housing hole (33, 43) penetrates the cylinder (31, 41) in the thickness direction.

[0052] As shown in Figure 3, the first cylinder (31) has a first passage (16a) which is part of the intake passage (16). The first passage (16a) is a bottomed hole that extends in the thickness direction of the first cylinder (31). The first passage (16a) is located to the right of the vane housing hole (33) in Figure 4. The second cylinder (41) has a second passage (16b) which is part of the intake passage (16). The second passage (16b) penetrates the second cylinder (41) in the thickness direction. The second passage (16b) is located to the right of the vane housing hole (43) in Figure 5.

[0053] The cylinders (31, 41) have intake ports (17, 18) that extend from the intake passage (16) toward the cylinder chambers (S1, S2). The first intake port (17) of the first cylinder (31) extends from the first passage (16a) toward the first cylinder chamber (S1). As shown in Figure 4, the first intake port (17) of the first cylinder (31) extends from above at a position where it is 30 degrees or less in a clockwise direction away from the vane housing hole (33) when viewed from above. The second intake port (18) of the second cylinder (41) extends from the second passage (16b) toward the second cylinder chamber (S2). As shown in Figure 5, the second intake port (18) of the second cylinder (41) extends from above at a position where it is 30 degrees or less in a clockwise direction away from the vane housing hole (43) when viewed from above. The intake ports (17, 18) extend toward the cylinder chambers (S1, S2) such that, when viewed from the axial direction, they are closer to the vane housing holes (33, 43) than to the intake passage (16).

[0054] A first recess (31a) is formed on the lower end surface (one end surface in the axial direction) of the first cylinder (31), and is elongated in plan view, extending radially inward toward the vane housing hole (33). A circular first injection opening (31b) is formed at the radially inward end of the bottom surface (31g) of this first recess (31a), opening in one axial direction. A first bolt insertion hole (31c) is formed at the radially outward end of the bottom surface (31g) of this first recess (31a), penetrating in the axial direction. As shown in Figures 10 and 12, a concave portion (31h) is formed in most of the radially inward half of the bottom surface (31g) of the first recess (31a), which is more recessed than the other areas. An annular valve seat (31i) is provided protruding from the outer periphery of the first injection opening (31b) in the concave portion (31h).

[0055] Between the first recess (31a) on the lower end face (one axial end face) of the first cylinder (31) and the first cylinder chamber (S1), a first communication groove (31d) is formed, which is narrower than the first recess (31a), and extends in the longitudinal direction of the first recess (31a). Therefore, this first communication groove (31d) is also inclined toward the vane housing hole (33) toward the radially inward side of the first cylinder (31). The first recess (31a) and the first communication groove (31d) constitute a first valve housing portion (31j) that is recessed toward the outward side from the inner circumferential surface of the first cylinder (31).

[0056] As shown in Figure 7, the first cylinder (31) has an upper end portion of the fourth passage (61d), a first transverse passage (31e) extending radially inward from the upper end of the fourth passage (61d), and a first connecting passage (31f) extending downward from the radially inward end of the first transverse passage (31e) and axially connecting the first transverse passage (31e) and the first injection opening (31b). These first transverse passage (31e) and first connecting passage (31f) are part of the second passage (61b). As shown in Figure 4, the first transverse passage (31e) extends from the vane housing hole (33) at an angle of 30 degrees or less in a counterclockwise direction (opposite direction to the first intake port (17)) when viewed from above. The directions in which the first transverse passage (31e) and the first recess (31a) extend are offset by approximately 30 degrees from each other. In other words, the angle α between the first transverse channel (31e) and the first recess (31a) is approximately 30 degrees. By offsetting the directions in which the first transverse channel (31e) and the first recess (31a) extend by 5 degrees or more, that is, by making the angle α 5 degrees or more, the first bolt insertion hole (31c) can be made less likely to interfere with the first transverse channel (31e).

[0057] As shown in Figure 12, the first recess (31a) of the first cylinder (31) houses the elongated first reed valve (63) and the elongated first valve retainer (64) shown in Figures 11 and 13, with their longitudinal directions aligned with the longitudinal direction of the first recess (31a). A retaining hole (62a) is formed through one longitudinal end of the first reed valve (62). A retaining hole (64a) is also formed through the corresponding location on the first valve retainer (64).

[0058] The first reed valve (63) is a long, flat, thin plate-like member. The first reed valve (63) is made of a metal such as spring steel or iron. The first reed valve (63) is flexible.

[0059] The first valve retainer (64) is positioned opposite the first reed valve (63). The first valve retainer (64) has a first surface facing the first reed valve (63), a second surface facing the first cylinder chamber (S1), and a third surface opposite the first surface. The radially inner end of the first surface of the first valve retainer (64) facing the first reed valve (63) is inclined so that it moves further away from the bottom surface (31g) of the first recess (31a) as it moves radially inward.

[0060] The first valve retainer (64) has a third-side valve retainer groove (64b) which serves as a second valve retainer groove, extending along the third surface opposite to the first surface facing the first reed valve (63), and a circular communication hole (64d) which connects the third-side valve retainer groove (64b) and the first valve housing (31j). The third-side valve retainer groove (64b) has a groove opening (64c) on the first cylinder chamber (S1) side. The communication hole (64d) has a hole opening (64e) on the first surface of the first valve retainer (64) facing the first reed valve (63).

[0061] Furthermore, the third side valve retaining groove (64b) and the communication hole (64d) constitute a valve retaining passage (P1) connecting the first surface of the first valve retainer (64) facing the first reed valve (63) and the second surface facing the first cylinder chamber (S1).

[0062] The first reed valve (63) and the first valve retainer (64) are attached to the first cylinder (31) by inserting a bolt (65) through the first bolt insertion hole (31c) of the first cylinder (31) and fastening the tip of the bolt (65) to the fastening hole (63a) of the first reed valve (63) and the fastening hole (64a) of the first valve retainer (64). The head of the bolt (65) and other parts of the bolt (65) other than the tip are housed in the first bolt insertion hole (31c) of the first cylinder (31). In this state, the first reed valve (63) can open and close the first injection opening (31b) by raising and lowering one end of its (the end opposite the fastening hole (63a)) in the axial direction of the shaft (90). The bottom surface (31g) of the first recess (31a) (the surface of the first valve housing (31j) on the front head (50) side) constitutes the valve mounting surface of the first valve housing (31j). In this way, the first reed valve (63) is positioned at the end of the injection passage (61). The first reed valve (63) is fixed to the bottom surface (31g) of the first recess (31a) radially outward from the first injection opening (31b) of the first cylinder (31).

[0063] In this state, the center line (C1) extending in the longitudinal direction of the first reed valve (63) coincides with the opening on the first cylinder chamber (S1) side of the first valve housing (31j). This center line (C1) passes between the fixing point with the bottom surface (31g) of the first recess (31a) of the first reed valve (63) and the point opposite the first injection opening (31b) in the closed state.

[0064] Furthermore, the centerline (CH) of the communication hole (64d) intersects with the centerline (C1) extending longitudinally of the first reed valve (63). Also, the centerline (C1) extending longitudinally of the first reed valve (63) coincides with the groove opening (64c) of the third side valve retaining groove (64b).

[0065] Furthermore, the entire opening (64e) of the communication hole (64d) of the first valve retainer (64) overlaps with the opening and closing direction of the first injection opening (31b) and the first reed valve (63). Therefore, the entire opening (64e) of the communication hole (64d) of the first valve retainer (64) overlaps with the region inside the outer edge of the valve seat (31i) and the opening and closing direction of the first reed valve (63). As shown in Figure 12, the entire region R1 of the opening (64e) of the communication hole (64d) overlaps with the region R2 inside the outer edge of the valve seat (31i). Alternatively, only a portion of the opening (64e) of the communication hole (64d) of the first valve retainer (64) may overlap with the opening and closing direction of the first injection opening (31b) and the first reed valve (63).

[0066] A second recess (41a) is formed on the upper end surface (one end surface in the axial direction) of the second cylinder (41), and is elongated in plan view, extending radially inward toward the vane housing hole (43) of the second cylinder (41). A second injection opening (41b) is formed at the radially inward end of the bottom surface (41g) of this second recess (41a), opening in the axial direction. A second bolt insertion hole (41c) is formed at the radially outward end of the bottom surface (41g) of this second recess (41a), penetrating in the axial direction.

[0067] Between the second recess (41a) and the second cylinder chamber (S2) on the lower end surface (one axial end surface) of the second cylinder (41), a second communication groove (41d) is formed, which is narrower than the second recess (41a), and extends in the longitudinal direction of the second recess (41a). Therefore, this second communication groove (41d) is also inclined toward the vane housing hole (43) toward the radially inward side of the second cylinder (41). The second recess (41a) and the second communication groove (41d) constitute a second valve housing portion (41j) that is recessed outward from the inner circumferential surface of the second cylinder (41). Although not shown, the bottom surface shapes of the second recess (41a) and the second communication groove (41d) are the same as the bottom surface shapes of the first recess (31a) and the first communication groove (31d).

[0068] As shown in Figure 7, the second cylinder (41) has a lower end portion of the fourth passage (61d), a second transverse passage (41e) extending radially inward from the lower end of the fourth passage (61d), and a second connecting passage (41f) extending upward from the radially inward end of the second transverse passage (41e) and axially connecting the second transverse passage (41e) and the second injection opening (41b). These second transverse passage (41e) and second connecting passage (41f) are part of the third passage (61c). As shown in Figure 5, the second transverse passage (41e) extends from the vane housing hole (43) at an angle of 30 degrees or less in a counterclockwise direction (opposite direction to the second intake port (18)) when viewed from above. The directions in which the second transverse passage (41e) and the second recess (41a) extend are offset by approximately 30 degrees from each other. In other words, the angle β between the second transverse channel (41e) and the second recess (41a) is approximately 30 degrees. By offsetting the directions in which the second transverse channel (41e) and the second recess (41a) extend by 5 degrees or more, that is, by making the angle β 5 degrees or more, the second bolt insertion hole (41c) can be made less likely to interfere with the second transverse channel (41e).

[0069] The second recess (41a) of the second cylinder (41) houses a second reed valve (66) having the same configuration as the first reed valve (63) and a second valve retainer (67) having the same configuration as the first valve retainer (64).

[0070] As shown in Figure 8, the second reed valve (66) and the second valve retainer (67) are attached to the second cylinder (41) in the same manner as the first reed valve (62) and the first valve retainer (64) by inserting a bolt (68) through the second bolt insertion hole (41c) of the second cylinder (41) and fastening the tip of the bolt (68) to the fastening hole (66a) of the second reed valve (66) and the fastening hole (67a) of the second valve retainer (67). The head of the bolt (68) and other parts of the bolt (68) other than the tip are housed in the second bolt insertion hole (41c) of the second cylinder (41). In this state, the second reed valve (66) can open and close the second injection opening (41b) by raising and lowering one end of it (the end opposite the fastening hole (66a)) in the axial direction of the shaft (90). The bottom surface (41g) of the second recess (41a) (the surface of the second valve housing (41j) on the rear head (56) side) constitutes the valve mounting surface of the second valve housing (41j). In this way, the second reed valve (66) is positioned at the end of the injection passage (61). The second reed valve (66) is fixed to the bottom surface (41g) of the second recess (41a) radially outward from the second injection opening (41b) of the second cylinder (41).

[0071] In this state, as shown in Figure 5, the center line (C2) extending in the longitudinal direction of the second reed valve (66) also coincides with the opening on the second cylinder chamber (S2) side of the second valve housing (41j). This center line (C2) passes between the fixing point with the bottom surface (41g) of the second recess (41a) of the second reed valve (66) and the point opposite the second injection opening (41b) in the closed state.

[0072] (2-4-2) Piston The first piston (34) is housed in the first cylinder (31). The first piston (34) rotates eccentrically within the first cylinder chamber (S1). The first piston (34) is configured to slide against both the front head (50) and the middle plate (55).

[0073] As shown in Figure 4, the first piston (34) has a first piston body (roller) (35) and a first vane (36). The first piston body (35) is formed in an annular shape. The first piston body (35) is formed in a slightly thick-walled cylindrical shape. The first eccentric portion (91) of the shaft (90) is inserted through and connected to the first piston body (35). The first piston body (35) pivots along the inner circumferential surface of the first cylinder chamber (S1) of the first cylinder (31) as the first eccentric portion (91) rotates.

[0074] The first vane (36) is integrally projected from the outer circumferential surface of the first piston body (35). The first vane (36) is housed in the vane housing hole (33) of the first cylinder (31). The first vane (36) is sandwiched from both sides by bushings (70) fitted into the vane housing hole (33). The first vane (36) is supported by the first cylinder (31) via these bushings (70) so as to be able to swing and move back and forth. The first vane (36) divides the first cylinder chamber (S1) into a first intake space (71) and a first discharge space (72). When the first piston (34) rotates, the first vane (36) restricts the rotation of the first piston (34) itself. As a result, the first piston (34) rotates along the inner surface of the first cylinder chamber (S1) without rotating.

[0075] The second piston (44) is identical to the first piston (34) in shape, dimensions, and material. The first piston (34) and the second piston (44) are positioned inverted relative to each other in the vertical direction.

[0076] The second piston (44) is housed in the second cylinder (41). The second piston (44) rotates eccentrically in the second cylinder chamber (S2). The second piston (44) is configured to slide against both the rear head (56) and the middle plate (55).

[0077] As shown in Figure 5, the second piston (44) has a second piston body (roller) (45) and a second vane (46). The second piston body (45) is formed in an annular shape. The second piston body (45) is formed in a slightly thick-walled cylindrical shape. The second piston body (45) is connected to the shaft (90) by having the second eccentric portion (92) of the shaft inserted through it. The second piston body (45) pivots along the inner circumferential surface of the second cylinder chamber (S2) of the second cylinder (41) as the second eccentric portion (92) rotates.

[0078] The second vane (46) is integrally projected from the outer circumferential surface of the second piston body (45). The second vane (46) is housed in the vane housing hole (43) of the second cylinder (41). The second vane (46) is sandwiched from both sides by a bush (70) fitted into the vane housing hole (43). The second vane (46) is supported by the second cylinder (41) via this bush (70) so as to be able to swing and move back and forth. The second vane (46) divides the second cylinder chamber (S2) into a second intake space (75) and a second discharge space (not shown). When the second piston (44) is swirling, the second vane (46) restricts the rotation of the second piston (44) itself. As a result, the second piston (44) swivels along the inner surface of the second cylinder chamber (S2) without rotating.

[0079] (2-4-3) Front Head The front head (50) is positioned on the side of the first cylinder (31) opposite the middle plate (55). The front head (50) closes the axial end of the first cylinder (31). Specifically, the front head (50) closes the upper end surface (the surface on the motor (20) side) of the first cylinder (31). The front head (50) comprises a first main body (50a) and an upper bearing portion (50b). The first main body (50a) and the upper bearing portion (50b) are integrally formed.

[0080] The first main body (50a) is formed in a generally circular, thick plate shape. The lower surface of the first main body (50a) is in close contact with the upper end surface of the first cylinder (31). The upper bearing portion (50b) is formed in a cylindrical shape that extends from the first main body (50a) toward the electric motor (20) side (upper side in Figure 3). The upper bearing portion (50b) is positioned in the center of the first main body (50a). The upper bearing portion (50b) rotatably supports the upper shaft portion (90a) of the shaft (90).

[0081] As shown in Figure 8, the first main body (50a) has a first discharge port (51). The first discharge port (51) penetrates the first main body (50a) in the thickness direction. The first discharge port (51) connects the internal space (R) and the first discharge space (72).

[0082] The area surrounding the first discharge port (51) in the first main body (50a) is a first thin-walled section (52) that has a thinner axial thickness than other parts.

[0083] A first discharge valve (53), which is a reed valve, is provided at the first discharge port (51). The first discharge valve (53) is positioned to cover the first discharge port (51). The first discharge valve (53) moves away from the first discharge port (51) when the pressure of the refrigerant in the first discharge space (72) of the first cylinder chamber (S1) exceeds a predetermined value. When the first discharge valve (53) moves away from the first discharge port (51), the refrigerant is discharged through the first discharge port (51) from the first discharge space (72) of the first cylinder chamber (S1) into the internal space (R). After the refrigerant has been discharged into the internal space (R), the first discharge valve (53) again covers the first discharge port (51).

[0084] (2-4-4) Middle Plate The middle plate (55) is positioned between the first cylinder (31) and the second cylinder (41). The middle plate (55) closes the axial end of the first cylinder (31) and the axial end of the second cylinder (41). Specifically, the middle plate (55) closes the lower end surface of the first cylinder (31) and the upper end surface of the second cylinder (41).

[0085] A central hole is formed in the middle of the middle plate (55), passing through it axially. The intermediate shaft portion (90b) of the shaft (90) is inserted through the central hole.

[0086] As shown in Figure 3, the middle plate (55) has an intermediate passage (16c) which is part of the intake passage (16). The intermediate passage (16c) penetrates the middle plate (55) in the axial direction. The intermediate passage (16c) connects the first passage (16a) and the second passage (16b).

[0087] The middle plate (55) is penetrated by the fourth channel (61d), which extends axially from the second channel (61b) of the injection channel (61).

[0088] (2-4-5) Rear Head The rear head (56) is positioned on the side of the second cylinder (41) opposite the middle plate (55). The rear head (56) closes the axial end of the second cylinder (41). Specifically, the rear head (56) closes the lower end surface of the second cylinder (41) (the surface opposite to the electric motor (20)).

[0089] The upper surface of the rear head (56) is in close contact with the lower end surface of the second cylinder (41). The rear head (56) rotatably supports the lower shaft portion (90c) of the shaft (90).

[0090] The rear head (56) has a first insertion hole (19) into which the intake pipe (14) is inserted, and a second insertion hole (60) into which the injection pipe (9c) is inserted. The first insertion hole (19) and the second insertion hole (60) each extend radially.

[0091] A lower passage (16d), which is part of the suction passage (16), extends from the first insertion hole (19). The lower passage (16d) extends upward along the axial direction from the tip of the first insertion hole (19). The upper end of the lower passage (16d) communicates with the second passage (16b).

[0092] An injection channel (61) extends from the second insertion hole (60). A portion of the first channel (61a) of the injection channel (61) is formed in the rear head (56).

[0093] As shown in Figures 7 and 8, the rear head (56) has a second discharge port (57). The second discharge port (57) penetrates the rear head (56) in the thickness direction. The second discharge port (57) communicates the internal space (R) with the second discharge space (not shown).

[0094] The area around the second discharge port (57) in the rear head (56) is a second thin-walled section (58) that is thinner in the axial direction than other parts.

[0095] A second discharge valve (59) is provided at the second discharge port (57). The second discharge valve (59) is positioned to cover the second discharge port (57). The second discharge valve (59) moves away from the second discharge port (57) when the pressure of the refrigerant in the second discharge space (not shown) exceeds a predetermined value. When the second discharge valve (59) moves away from the second discharge port (57), the refrigerant is discharged through the second discharge port (57) from the second discharge space (not shown) into the internal space (R). After the refrigerant has been discharged into the internal space (R), the second discharge valve (59) again covers the second discharge port (57).

[0096] (3) Operating Next, the operation of the compressor (1) will be explained with reference to Figure 14. The refrigerant compression operation by the first cylinder (31) and the first piston (34) and the refrigerant compression operation by the second cylinder (41) and the second piston (44) are basically the same, differing only by a 180° phase difference. In the following explanation, the refrigerant compression operation by the first cylinder (31) and the first piston (34) will be described in detail, while the refrigerant compression operation by the second cylinder (41) and the second piston (44) will not be explained.

[0097] In the compressor (1), when the electric motor (20) is started and the rotor (22) is rotated, the shaft (90) rotates and the first eccentric part (91) rotates eccentrically. As the first eccentric part (91) rotates eccentrically, the first piston (34) rotates along the inner surface of the first cylinder (31) while restricting its rotation.

[0098] The suction stroke for drawing refrigerant into the first cylinder chamber (S1) will now be described. When the shaft (90) rotates slightly from a state where its rotation angle is 0° (state shown in Figure 14(A)), the contact point between the first piston (34) and the first cylinder (31) passes the inner end of the first suction port (17). At this time, the suction of refrigerant into the first suction space (71) begins.

[0099] Refrigerant is drawn in from the suction pipe (14) through the suction passage (16) and the first suction port (17). As the rotation angle of the shaft (90) increases, the volume of the first suction space (71) gradually increases, and the amount of refrigerant drawn into the first suction space (71) increases (as shown in Figures 14(B) to (H)). This refrigerant suction stroke continues until the rotation angle of the shaft (90) reaches 360°, after which the process transitions to the discharge stroke.

[0100] The discharge stroke, in which the refrigerant is compressed and discharged in the first cylinder chamber (S1), will now be described. When the shaft (90) rotates slightly from a state where its rotation angle is 0° (state shown in Figure 14(A)), the contact point between the first piston (34) and the first cylinder (31) passes the inner circumference end of the first intake port (17) again. At this time, the containment of the refrigerant in the first intake space (71) is completed.

[0101] The first intake space (71), which was connected to the first intake port (17), becomes the first discharge space (72), which is connected only to the first discharge port (51). From this state, compression of the refrigerant in the first discharge space (72) begins. As the rotation angle of the shaft (90) increases, the volume of the first discharge space (72) decreases and the pressure in the first discharge space (72) increases. When the pressure in the first discharge space (72) exceeds a predetermined pressure, the first discharge valve (53) opens.

[0102] When the first discharge valve (53) opens, the refrigerant in the first discharge space (72) is discharged from the first discharge port (51), flows into the internal space (R) within the casing (10), and is then discharged to the outside of the compressor (1) via the discharge pipe (15). This refrigerant discharge stroke continues until the rotation angle of the shaft (90) reaches 360°, after which the process transitions to the suction stroke.

[0103] In this manner, the intake stroke and discharge stroke alternate in the first cylinder chamber (S1). In the second cylinder chamber (S2), the intake stroke and discharge stroke alternate with a 180° phase difference relative to the first cylinder chamber (S1). As a result, the compressor (1) continuously compresses the refrigerant.

[0104] Here, intermediate-pressure refrigerant, i.e., carbon dioxide (CO2), is injected into the first cylinder chamber (S1) and the second cylinder chamber (S2) from the injection passage (61) while compression is in progress. Specifically, if the pressure in the injection passage (61) is higher than that in the first cylinder chamber (S1), intermediate-pressure refrigerant is injected into the first cylinder chamber (S1) from the injection passage (61). On the other hand, if the pressure in the first cylinder chamber (S1) increases and the pressure in the first cylinder chamber (S1) becomes higher than that in the injection passage (61), the end of the first reed valve (63) provided in the injection passage (61) on the side of the retaining hole (63a) is pressed against the valve seat (31i) on the periphery of the first injection opening (31b), blocking the injection passage (61) and stopping the supply of intermediate-pressure refrigerant. In this embodiment 1, since CO2, which has a relatively high pressure, is used as the refrigerant, when refrigerant flows from the cylinder chamber (S1, S2) between the reed valves (63, 66) and the valve mounting surfaces (31g, 41g), the closing delay of the reed valves (63, 66) tends to be large. However, at this time, as shown by arrow X in Figure 12, refrigerant flows from the first cylinder chamber (S1) through the valve retainer passage (P1) between the first reed valve (63) and the first valve retainer (64). As a result, the pressure on the first reed valve (63) from the first valve retainer (64) side increases, making it easier for the first reed valve (63) to close. Therefore, the closing delay of the first reed valve (63) can be suppressed. Furthermore, as shown in Figure 12, during the process of the first reed valve (63) moving from an open state to a closed state, a refrigerant flow path (P2) communicating with the first cylinder chamber (S1) is formed between the first valve retainer (64) and the first reed valve (63), separate from the valve retainer flow path (P1). The hydraulic diameter of the valve retainer flow path (P1) is larger than the hydraulic diameter of this refrigerant flow path (P2). Therefore, refrigerant from the first cylinder chamber (S1) flows more easily through the valve retainer flow path (P1). In addition, the center line (C1) extending in the longitudinal direction of the first reed valve (63) coincides with the opening of the first valve housing (31j) on the first cylinder chamber (S1) side. As a result, compared to the case where the center line (C1) of the first reed valve (63) does not coincide with the opening on the first cylinder chamber (S1) side of the first valve housing (31j), the refrigerant pressure from the first cylinder chamber (S1) acts in a more balanced manner on both sides of the center line (C1) of the first reed valve (63).Furthermore, the centerline (CH) of the communication hole (64d) intersects with the centerline (C1) extending longitudinally of the first reed valve (63). As a result, the refrigerant pressure from the first cylinder chamber (S1) acts more evenly on both sides of the centerline (C1) of the first reed valve (63) compared to the case where the centerline (CH) of the communication hole (64d) does not intersect with the centerline (C1) of the first reed valve (63). In addition, the groove opening (64c) of the third face side valve retaining groove (64b) coincides with the centerline (C1) extending longitudinally of the first reed valve (63). Therefore, compared to the case where the groove opening (64c) does not coincide with the centerline (C1) of the first reed valve (63), the refrigerant pressure from the first cylinder chamber (S1) acts more evenly on both sides of the centerline (C1) of the first reed valve (63). Therefore, cracking of the first reed valve (63) due to the pressure of the refrigerant from the first cylinder chamber (S1) can be suppressed. In this embodiment 1, using CO2, which has a relatively high pressure, as the refrigerant makes the first reed valve (62) prone to cracking. However, as described above, by aligning the center line (C1) of the first reed valve (62) with the opening of the first cylinder chamber (S1) of the first valve housing (31j), cracking of the first reed valve (62) can be suppressed. In addition, since the opening (64e) of the communication hole (64d) of the first valve retainer (64) overlaps with the area inside the outer peripheral edge of the valve seat (31i) and the opening and closing direction of the first reed valve (63) over the entire length, cracking of the first reed valve (63) due to partial contact of the valve seat (31i) with the pressure of the refrigerant flowing out from the opening (64e) of the communication hole (64d) can be suppressed.

[0105] Similarly, if the pressure in the injection passage (61) is higher than that in the second cylinder chamber (S2), intermediate-pressure refrigerant is injected from the injection passage (61) into the second cylinder chamber (S2). On the other hand, if the pressure in the second cylinder chamber (S2) increases and becomes higher than that in the injection passage (61), the end of the second reed valve (66) provided in the injection passage (61) on the side of the retaining hole (66a) is pressed against the periphery of the second injection opening (41b), blocking the injection passage (61) and stopping the supply of intermediate-pressure refrigerant. In this case as well, as described above for the first valve retainer (64), delay in closing and cracking of the second reed valve (66) can be suppressed. In this way, the rotary compressor (1) improves compression efficiency by injecting intermediate-pressure refrigerant.

[0106] (Embodiment 2) Figure 15 is a diagram corresponding to Figure 12 of Embodiment 2, and Figure 16 is a diagram corresponding to Figure 13 of Embodiment 2. In Embodiment 2, a first surface-side valve retaining groove (64f) is formed as a first valve retaining groove at the end of the first surface of the first valve retainer (64) facing the first reed valve (63) on the first cylinder chamber (S1) side. This first surface-side valve retaining groove (64f) has a groove opening (64g) on ​​the first cylinder chamber (S1) side. This first surface-side valve retaining groove (64f) constitutes a valve retaining passage (P1). Furthermore, the center line (C1) extending in the longitudinal direction of the first reed valve (63) coincides with the groove opening (64g) of the first surface-side valve retaining groove (64f). The same applies on the second cylinder (41) side.

[0107] The other components are the same as in Embodiment 1, so a detailed explanation will be omitted.

[0108] According to this second embodiment, the groove opening (64g) of the first face-side valve retaining groove (64f) coincides with the center line (C1) extending in the longitudinal direction of the first reed valve (63). As a result, the refrigerant pressure from the first cylinder chamber (S1) acts more evenly on both sides of the center line (C1) of the first reed valve (63) compared to the case where the groove opening (64g) of the first face-side valve retaining groove (64f) does not coincide with the center line (C1) of the first reed valve (63). Therefore, it is possible to suppress the cracking of the first reed valve (63) due to the refrigerant pressure from the first cylinder chamber (S1). The same applies to the second cylinder (41) side.

[0109] <Other Embodiments> The piston (34,44) and the vane (36,46) do not necessarily have to be integrally formed. The piston (34,44) and the vane (36,46) may be connected by a hinge.

[0110] Furthermore, although the present invention was applied to a rotary compressor (1) having two cylinders (31, 41) in embodiments 1 and 2 above, the present invention can also be applied to a rotary compressor (1) having only one cylinder.

[0111] While embodiments and modifications have been described above, it will be understood that a variety of changes in form and details are possible without departing from the spirit and scope of the claims. Furthermore, the embodiments, modifications, and other embodiments described above may be combined or substituted as appropriate, as long as they do not impair the functions covered by this disclosure.

[0112] The designations "1st," "2nd," "3rd," etc., mentioned above are used to distinguish between the terms to which these designations are attached, and do not limit the number or order of those terms. [Industrial applicability]

[0113] As described above, this disclosure is useful for rotary compressors and refrigeration systems equipped therewith. [Explanation of Symbols]

[0114] 1. Rotary Compressor S1 First Cylinder Chamber S2 Second Cylinder Chamber 31. First cylinder 31b First injection opening 31g Bottom surface (valve mounting surface) 31i valve seat 31j First valve housing 34 First Piston 41 Second Cylinder 41b Second injection opening 41g Bottom surface (valve mounting surface) 41j Second valve housing 44. Second piston 50 Front head (2nd bearing) 56 Rear head (first bearing) 61 Injection channel 63. First reed valve 64. First valve restraint 64b Third side valve retaining groove (second valve retaining groove) 64c groove opening 64d communication hole 64e hole opening 64f First side valve retaining groove (first valve retaining groove) 64g groove opening 66. Second reed valve 67. Second valve retainer 90 Shaft (drive shaft) 100 Refrigeration equipment C1,C2,CH center line P1 Valve retaining passage P2 Refrigerant flow path

Claims

1. A rotary compressor having an injection channel (61), Pistons (34, 44) and A drive shaft (90) that drives the pistons (34, 44), The first bearing (56) and the second bearing (50) support the drive shaft (90), The cylinder (31, 41) houses the pistons (34, 44) and has cylinder chambers (S1, S2) partitioned by its inner circumferential surface, The reed valves (63, 66) are arranged in the injection channel (61), The reed valves (63, 66) are opposed to valve retainers (64, 67), and the valves are further provided to be positioned opposite each other. The cylinders (31, 41) are provided with valve housing portions (31j, 41j) that are recessed outward from the inner circumferential surface and house the reed valves (63, 66) and the valve retainers (64, 67). The valve mounting surfaces (31g, 41g) of the valve housing portions (31j, 41j), which are the surfaces on the first bearing (56) side or the second bearing (50) side, are provided with injection openings (31b, 41b) that are opened and closed by the reed valves (63, 66). The reed valves (63, 66) are fixed to the valve mounting surfaces (31g, 41g) of the valve housings (31j, 41j) radially outward from the injection openings (31b, 41b) of the cylinders (31, 41). A rotary compressor in which a valve retainer passage (P1) is formed in the valve retainer (64, 67), connecting the first surface of the valve retainer (64, 67) facing the reed valve (63, 66) and the second surface facing the cylinder chamber (S1, S2).

2. In the rotary compressor according to claim 1, A rotary compressor in which, during the process of closing the reed valves (63, 66) from an open state, a refrigerant flow path (P2) communicating with the cylinder chambers (S1, S2) is formed between the valve retainers (64, 67) and the reed valves (63, 66), separately from the valve retainer flow path (P1).

3. In the rotary compressor according to claim 2, A rotary compressor in which the longitudinally extending centerlines (C1, C2) of the reed valves (63, 66) coincide with the openings of the valve housing (31j, 41j) on the cylinder chamber (S1, S2) side.

4. In the rotary compressor according to claim 1, The first surface of the valve retainer (64, 67) has a first valve retainer groove (64f) having a groove opening (64g) on ​​the cylinder chamber (S1, S2) side. A rotary compressor in which the first valve retaining groove (64f) constitutes the valve retaining passage (P1).

5. In the rotary compressor according to claim 4, A rotary compressor in which the longitudinally extending centerlines (C1, C2) of the reed valves (63, 66) coincide with the groove opening (64g) of the first valve retaining groove (64f).

6. In the rotary compressor according to claim 1, The valve retainer (64, 67) has a second valve retainer groove (64b) that extends along the third surface opposite to the first surface and has a groove opening (64c) on the cylinder chamber (S1, S2) side, and a communication hole (64d) that has a hole opening (64e) on the first surface and connects the second valve retainer groove (64b) and the valve housing (31j, 41j). A rotary compressor in which the second valve retaining groove (64b) and the communication hole (64d) constitute the valve retaining passage (P1).

7. In the rotary compressor according to claim 6, The rotary compressor wherein the center line (CH) of the communication hole (64d) intersects with the center lines (C1, C2) extending in the longitudinal direction of the reed valves (63, 66).

8. In the rotary compressor according to claim 7, A rotary compressor in which the longitudinally extending centerlines (C1, C2) of the reed valves (63, 66) coincide with the groove opening (64c) of the second valve retaining groove (64b).

9. In the rotary compressor according to claim 6, A rotary compressor in which at least a portion of the opening (64e) of the communication hole (64d) of the valve retainer (64, 67) overlaps with the injection opening (31b, 41b) and the reed valve (63, 66) in the opening and closing direction.

10. In the rotary compressor according to claim 9, An annular valve seat (31i) is provided protruding from the outer periphery of the injection opening (31b, 41b) of the cylinder (31, 41). A rotary compressor in which the opening (64e) of the communication hole (64d) of the valve retainer (64, 67) overlaps with the region inside the outer peripheral edge of the valve seat (31i) and the opening and closing direction of the reed valve (63, 66) over the entire length of the valve retainer (64, 67).

11. In the rotary compressor according to claim 6, In the process of changing the reed valves (63, 66) from an open state to a closed state, a refrigerant flow path (P2) communicating with the cylinder chambers (S1, S2) is formed between the valve retainers (64, 67) and the reed valves (63, 66). A rotary compressor in which the hydraulic diameter of the valve retaining passage (P1) is larger than the hydraulic diameter of the refrigerant passage (P2).

12. In the rotary compressor according to claim 1, A rotary compressor that uses CO2 as a refrigerant.

13. A refrigeration system comprising a rotary compressor (1) according to any one of claims 1 to 12.

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