Rotary compressors and refrigeration cycle systems

Abstract

The objective is to provide a rotary compressor and refrigeration cycle system that can suppress performance degradation caused by the discharge valve. [Solution] The rotary compressor of this embodiment has a compression element. The compression element has a cylinder, a rotor, and a plurality of vanes. The vanes divide the cylinder chamber into an operating chamber. A first discharge passage is formed in the end plate, facing the end face of the rotor. A second discharge passage is formed in the rotor, connecting the first discharge passage to the operating chamber. During the rotation process of the rotor, a connected state and a disconnected state are switched. The connected state is when the first discharge passage and the second discharge passage are in communication. The disconnected state is when the first discharge passage and the second discharge passage are not in communication. By connecting the first discharge passage and the second discharge passage, the working fluid is discharged from the operating chamber through the first discharge passage and the second discharge passage.

Description

Technical Field

[0001] Embodiments of the present invention relate to a rotary compressor and a refrigeration cycle apparatus.

Background Art

[0002] In a compressor, for example, a discharge port that is opened and closed by a discharge valve is formed in a cylinder. In order to discharge all of the working fluid in the working chamber, it is desirable to provide the discharge port at a position as downstream as possible. However, as the position moves downstream, the distance between the outer peripheral surface of the rotor and the inner peripheral surface of the cylinder becomes smaller. Therefore, if the discharge port is provided at a downstream position, the cross-sectional area of the flow path before flowing into the discharge port becomes smaller, and the flow path loss may increase. Therefore, a structure may be adopted in which discharge ports are provided on the upstream side and the downstream side in the rotational direction, and these discharge ports are opened and closed by discharge valves. In a compressor, it is required to suppress a decrease in performance due to an increase in over-compression loss, re-expansion loss, etc. associated with the opening and closing of the discharge valve.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The problem to be solved by the present invention is to provide a rotary compressor and a refrigeration cycle apparatus that can suppress a decrease in performance caused by a discharge valve.

Means for Solving the Problems

[0005] The rotary compressor of Embodiment 1 comprises a case, a drive shaft, a drive element, and a compression element. The drive shaft is housed in the case. The drive element rotates the drive shaft. The compression element compresses the working fluid. The compression element comprises a cylinder, a rotor, and a plurality of vanes. The cylinder has an opening at one end that is closed by an end plate to form a cylinder chamber. The rotor is cylindrical in shape. The rotor rotates within the cylinder. The plurality of vanes are movable back and forth in the radial direction of the rotor. The cylinder chamber is formed between the inner circumferential surface of the cylinder and the outer circumferential surface of the rotor. A minimum gap is formed in the cylinder chamber where the distance between the inner circumferential surface of the cylinder and the outer circumferential surface of the rotor is minimized. The vanes divide the cylinder chamber into an operating chamber. The operating chamber changes its volume as the rotor rotates, thereby drawing in the working fluid upstream, compressing the working fluid, and discharging it downstream. A first discharge passage is formed in the end plate, facing the end face of the rotor. A second discharge passage is formed in the rotor, connecting the first discharge passage to the working chamber. During the rotation process of the rotor, a connected state and a disconnected state are switched. The connected state is when the first discharge passage and the second discharge passage are in communication. The disconnected state is when the first discharge passage and the second discharge passage are not in communication. When the first discharge passage and the second discharge passage are in communication, the working fluid is discharged from the working chamber through the first discharge passage and the second discharge passage.

[0006] The rotary compressor of Embodiment 2 is based on the rotary compressor described in Embodiment 1. The first discharge passage is arc-shaped and follows the outer edge of the rotor. The first discharge passage is groove-shaped, with a depth greater than its width. The opening of the first discharge passage is sealed by the end face of the rotor and the end face of the vane in the non-communicating state.

[0007] The rotary compressor of embodiment 3 is based on the rotary compressor described in embodiment 1 or 2. When viewed from a direction parallel to the drive shaft, a recess is formed on the inner circumferential surface of the cylinder facing the second discharge passage, which is concave toward the radially outward direction of the rotor. The recess forms a flow space through which the working fluid discharged from the working chamber can flow.

[0008] The rotary compressor of embodiment 4 is based on the rotary compressor described in any one of embodiments 1 to 3. A discharge port is formed in the cylinder. The discharge port is opened and closed by a discharge valve. The discharge port is formed to open on the inner circumferential surface. The working fluid in the working chamber is discharged from both the discharge port and the first discharge passage and the second discharge passage before the vane passes through the discharge port. After the vane passes through the discharge port, the working fluid in the working chamber is discharged from only the first discharge passage and the second discharge passage, out of the first and second discharge passages.

[0009] The rotary compressor of Embodiment 5 is based on the rotary compressor described in any one of Embodiments 1 to 4. The rotary compressor of Embodiment 5 has a plurality of second discharge passages. In the first stage, when the vanes are located away from the discharge port, only a portion of the plurality of second discharge passages communicates with the first discharge passage. In the second stage, when the vanes pass through the discharge port, a larger number of the second discharge passages communicate with the first discharge passage than in the first stage.

[0010] The rotary compressor of embodiment 6 is based on the rotary compressor described in any one of embodiments 1 to 5. An injection circuit is provided in the cylinder. The injection circuit injects intermediate-pressure refrigerant into the working chamber. An injection passage is formed in the end plate. The injection passage communicates with the injection circuit. The injection passage opens toward the end face of the rotor. The intermediate-pressure refrigerant flows into the working chamber as the second discharge passage communicates with the injection passage.

[0011] The refrigeration cycle device of the embodiment comprises a rotary compressor, a radiator, an expansion device, and a heat absorber, as described in any one of embodiments 1 to 6. The radiator is connected to the rotary compressor. The expansion device is connected to the radiator. The heat absorber is connected to the expansion device. [Brief explanation of the drawing]

[0012] [Figure 1] A schematic diagram of a refrigeration cycle system, including a cross-sectional view of a rotary compressor according to the first embodiment. [Figure 2] Cross-sectional view AA in Figure 1. [Figure 3] Cross-sectional view of BB in Figure 1. [Figure 4] A cross-sectional view illustrating the operation of a rotary compressor according to the first embodiment. [Figure 5] A cross-sectional view of a rotary compressor according to the first embodiment. [Figure 6] A cross-sectional view illustrating the operation of a rotary compressor according to the first embodiment. [Figure 7] A cross-sectional view illustrating the operation of a rotary compressor according to the first embodiment. [Figure 8] A cross-sectional view of a rotary compressor according to the second embodiment. [Figure 9] A cross-sectional view of a rotary compressor according to the second embodiment. [Modes for carrying out the invention]

[0013] Hereinafter, the rotary compressor and the refrigeration cycle device of the embodiment will be described with reference to the drawings.

[0014] FIG. 1 is a schematic configuration diagram of the refrigeration cycle device of the embodiment. FIG. 1 includes a cross-sectional view of the rotary compressor of the first embodiment. FIG. 2 is a cross-sectional view taken along line A-A in FIG. 1. FIG. 3 is a cross-sectional view taken along line B-B in FIG. 1. FIGS. 4 to 7 are diagrams for explaining the operation of the rotary compressor.

[0015] As shown in FIG. 1, the refrigeration cycle device 100 of the present embodiment includes a rotary compressor 102, a four-way valve 103, a first heat exchanger 104, an expansion device 105, a second heat exchanger 106, and a refrigerant flow path 108 for circulating a refrigerant (fluid) through these components. The refrigerant circulates through the refrigeration cycle device 100 while undergoing a phase change.

[0016] The rotary compressor 102 has a compressor main body 111 and an accumulator (gas-liquid separator) 112. The rotary compressor 102 compresses a gas refrigerant that is a working fluid.

[0017] The four-way valve 103 reverses the flow direction of the refrigerant in the refrigerant flow path 108 of the first heat exchanger 104, the expansion device 105, and the second heat exchanger 106. When the four-way valve 103 is in the state shown in FIG. 1, the refrigerant discharged from the rotary compressor 102 (compressor main body 111) flows through the first heat exchanger 104, the expansion device 105, and the second heat exchanger 106 in this order. At this time, the first heat exchanger 104 functions as a condenser (radiator), and the second heat exchanger 106 functions as an evaporator (heat absorber).

[0018] When the four-way valve 103 is switched from the state shown in FIG. 1, the refrigerant discharged from the rotary compressor 102 (compressor main body 111) flows through the second heat exchanger 106, the expansion device 105, and the first heat exchanger 104 in this order. At this time, the second heat exchanger 106 functions as a condenser (radiator), and the first heat exchanger 104 functions as an evaporator (heat absorber).

[0019] The condenser dissipates heat from the high-temperature and high-pressure gaseous refrigerant discharged from the rotary compressor 102 (compressor main body 111), and converts the high-temperature and high-pressure gaseous refrigerant into a high-pressure liquid refrigerant. The expansion device 105 reduces the pressure of the high-pressure liquid refrigerant fed from the condenser, and converts the high-pressure liquid refrigerant into a low-temperature and low-pressure gas-liquid two-phase refrigerant. For example, the expansion device 105 is an expansion valve. The expansion device 105 is connected to the first heat exchanger 104 and the second heat exchanger 106.

[0020] The evaporator converts the gas-liquid two-phase refrigerant fed from the expansion device 105 into a low-pressure gaseous refrigerant. In the evaporator, when the low-pressure gas-liquid two-phase refrigerant vaporizes, it absorbs the heat of vaporization from the surroundings, thereby cooling the surroundings. The low-pressure gaseous refrigerant that has passed through the evaporator is taken into the interior of the rotary compressor 102 (compressor main body 111) via the accumulator 112.

[0021] Thus, in the refrigeration cycle device 100, the refrigerant, which is the working fluid, circulates while undergoing a phase change between gas and liquid. The refrigerant dissipates heat during the process of changing from gas to liquid. The refrigerant absorbs heat during the process of changing from liquid to gas. The refrigeration cycle device 100 performs heating, cooling, defrosting, etc. by utilizing the heat dissipation or heat absorption of the refrigerant.

[0022] The accumulator 112 is a so-called gas-liquid separator. The accumulator 112 separates the gaseous refrigerant vaporized in the evaporator from the liquid refrigerant that has not been vaporized in the evaporator. The accumulator 112 supplies the separated gaseous refrigerant to the compressor main body 111.

[0023] (First Embodiment) The rotary compressor 102 according to the first embodiment will be described. The rotary compressor 102 is a so-called rotary compressor. The rotary compressor 102 is a sliding vane (rotary vane) type rotary compressor. The rotary compressor 102 compresses the low-pressure gaseous refrigerant taken into the interior thereof to obtain a high-temperature and high-pressure gaseous refrigerant.

[0024] The compressor body 111 comprises a sealed case 1 (case), a drive shaft 4, an electric motor 2 (drive element), and a compression mechanism 3 (compression element). The sealed case 1 houses the drive shaft 4, the electric motor 2, the compression mechanism 3, an upper bearing 8 (end plate), and a lower bearing 9.

[0025] The compressor body 111 is arranged with the axial direction of the drive shaft 4 and the sealed case 1 as the vertical direction. The drive shaft 4 has a central axis C. The central axis C coincides with the central axis of the sealed case 1. The direction along the central axis C of the drive shaft 4 and the sealed case 1 is the "axial direction". The axial direction is the direction parallel to the drive shaft 4. The direction passing through the central axis C and perpendicular to the axial direction is the "radial direction". The direction around the central axis C is the "circumferential direction".

[0026] The sealed case 1 is a cylindrical body with both axial ends sealed to form a sealed container. The electric motor 2 is housed in the upper part of the sealed case 1. The compression mechanism 3 is housed in the lower part of the sealed case 1. The electric motor 2 and the compression mechanism 3 are connected via a drive shaft 4. Lubricating oil is stored at the bottom of the sealed case 1. A portion of the compression mechanism 3 is immersed in the lubricating oil.

[0027] The electric motor 2 is, for example, a so-called inner rotor type DC brushless motor. The electric motor 2 is an electric motor comprising a stator 51 and a rotor 52. For example, the stator 51 is fixed to the inner circumferential surface of the upper part of the sealed case 1. The rotor 52 is positioned inside the stator 51 at a distance. The rotor 52 is fixed to the upper part of the drive shaft 4. The electric motor 2 rotates the rotor 5 via the drive shaft 4.

[0028] The compression mechanism 3 comprises a cylinder 7, a rotor 5, a plurality of vanes 12 (see Figure 2), an upper bearing 8 (end plate), a lower bearing 9, and a muffler 30. The compression mechanism 3 compresses the refrigerant. The compression mechanism 3 draws in refrigerant from the accumulator 112.

[0029] The axial direction of the cylinder 7 is parallel to the axial direction of the drive shaft 4. The drive shaft 4 passes through the cylinder 7 in the vertical direction. As shown in Figure 2, the cylinder 7 has a cylinder chamber 31. The cylinder chamber 31 passes through the cylinder 7 in the axial direction. The central axis of the cylinder chamber 31 is eccentric with respect to the central axis of the cylinder 7. The cylinder chamber 31 functions as an operating chamber 10 into which the refrigerant is introduced.

[0030] The cylinder 7 has a suction passage 13 and a discharge port 22b. The suction passage 13 penetrates the cylinder 7 radially. The suction passage 13 introduces gaseous refrigerant supplied from the accumulator 112 (see Figure 1) into the cylinder chamber 31.

[0031] As shown in Figure 4, a recess 21 is formed on the inner circumferential surface of the cylinder 7. The recess 21 is formed on the upper part of the cylinder 7. When viewed from a direction parallel to the radial direction, the recess 21 is, for example, rectangular in shape. The recess 21 is concave toward the radially outward direction. When viewed from a direction parallel to the axial direction, the recess 21 is positioned opposite a portion of the first discharge passage 18. The depth of the recess 21 increases from the upstream end to the circumferential center and decreases from the circumferential center to the downstream end. The circumferential center of the recess 21 is positioned opposite the downstream end of the first discharge passage 18 when viewed from a direction parallel to the axial direction.

[0032] The cross-section of the cylinder chamber 31 between the outer circumferential surface of the rotor 5 and the inner circumferential surface of the cylinder 7 is defined as the flow path cross-section of the cylinder chamber 31. The recess 21 increases the flow path cross-sectional area of ​​the cylinder chamber 31. The recess 21 forms a flow space through which the refrigerant discharged from the working chamber 10 can flow.

[0033] Because a recess 21 is formed on the inner circumferential surface of the cylinder 7, when the radial distance between the outer circumferential surface of the rotor 5 and the inner circumferential surface of the cylinder 7 in the working chamber 10 decreases during the final stage of compression, the flow path cross-sectional area when the refrigerant flows from the working chamber 10 into the second discharge communication passage 19 can be increased, thereby suppressing flow path losses.

[0034] As shown in Figure 2, a discharge unit 40 is formed in the cylinder 7. The discharge unit 40 has a discharge port portion 22, a discharge valve 22a, and a regulating member 46. The discharge port portion 22 is formed in a concave shape on the outer circumferential surface of the cylinder 7. The radially outer opening of the discharge port portion 22 is closed by a cover member 49.

[0035] The discharge port 22b penetrates the cylinder 7 radially. The discharge port 22b is formed by opening onto the inner circumferential surface of the cylinder 7. The discharge port 22b connects the cylinder chamber 31 and the discharge port portion 22. The discharge port 22b discharges the gaseous refrigerant compressed in the cylinder chamber 31 to the outside of the cylinder chamber 31. The discharge port 22b is, for example, circular when viewed from a direction parallel to the radial direction.

[0036] The discharge valve 22a is located inside the discharge port 22. The discharge valve 22a is a reed valve, for example, made of a metal plate. The discharge valve 22a opens and closes the discharge port 22b. The regulating member 46 is positioned radially outward relative to the discharge valve 22a. The regulating member 46 restricts the discharge valve 22a from moving radially outward.

[0037] The rotor 5 is cylindrical in shape. The rotor 5 is located inside the cylinder chamber 31. The space between the outer circumferential surface of the rotor 5 and the inner circumferential surface of the cylinder 7 effectively functions as the cylinder chamber 31. The rotor 5 is positioned coaxially with the drive shaft 4. The rotation axis of the rotor 5 is eccentric with respect to the central axis of the cylinder chamber 31.

[0038] The radial separation distance (hereinafter simply referred to as "separation distance") between the outer surface of the rotor 5 and the inner surface of the cylinder 7 varies along the circumferential direction. The separation distance is maximum on the side of the eccentricity of the central axis of the cylinder chamber 31 relative to the central axis of the cylinder 7 (upward direction in Figure 2). On the other hand, the separation distance is minimum on the side of the opposite direction of eccentricity of the central axis of the cylinder chamber 31 (downward direction in Figure 2). The position where the separation distance is maximum is called the bottom dead center. The position where the separation distance is minimum is called the top dead center (minimum gap 6).

[0039] In the example shown in Figure 2, rotor 5 rotates counterclockwise. The upstream side of rotor 5's rotation is referred to as the "upstream side." The downstream side of rotor 5's rotation is referred to as the "downstream side." The direction of rotor 5's rotation is denoted by "θ." The upstream side is in the direction of -θ. The downstream side is in the direction of +θ.

[0040] The vanes 12 are formed in a flat plate shape from a metallic material. The vanes 12 are positioned in vane slots 11 formed in the rotor 5. The vane slots 11 penetrate the rotor 5 in the axial direction. For example, the vane slots 11 extend radially. The radially outer ends of the vane slots 11 open to the outer circumferential surface of the rotor 5. The vanes 12 are designed to move back and forth radially within the rotor 5. As the rotor 5 rotates, centrifugal force acts on the vanes 12. The vanes 12 are pressed against the inner circumferential surface of the cylinder 7. As the rotor 5 rotates, the vanes 12 move back and forth relative to the cylinder chamber 31.

[0041] For example, multiple vanes 12 are arranged at equal angular intervals in the circumferential direction. The vanes 12 divide the cylinder chamber 31 into working chambers 10 (suction chamber 10a and compression chamber 10b). More specifically, the vanes 12 divide the cylinder chamber 31 into a suction chamber 10a and a compression chamber 10b in the circumferential direction. As the rotor 5 rotates, the working chambers 10 move in the circumferential direction.

[0042] As the rotor 5 rotates, the working chamber 10 moves from top dead center to bottom dead center, increasing the volume of the working chamber 10. The working chamber 10, which communicates with the suction passage 13, draws in gaseous refrigerant from the upstream suction passage 13. As the rotor 5 rotates, the working chamber 10 moves from bottom dead center to top dead center, decreasing the volume of the working chamber 10. The working chamber 10 compresses the gaseous refrigerant as its volume decreases. The high-pressure gaseous refrigerant is discharged from the downstream discharge port 22b.

[0043] As shown in Figure 1, the upper bearing 8 (first bearing) is located on the upper side of the cylinder 7. The upper bearing 8 has a bearing portion 33 and a closing portion 34 (end plate). The bearing portion 33 rotatably supports the drive shaft 4 on the upper side of the cylinder 7. The closing portion 34 closes the opening on the upper side (one end side) of the cylinder chamber 31. A muffler communication passage 16 is formed on the upper surface of the closing portion 34. The muffler communication passage 16 is a recess that opens on the upper surface of the closing portion 34.

[0044] A first discharge passage 18 is formed in the closed section 34. The first discharge passage 18 is formed from the bottom of the muffler passage 16 to the lower surface of the closed section 34. The lower end of the first discharge passage 18 opens to the lower surface of the closed section 34. The lower end of the first discharge passage 18 faces the upper end surface 17 of the rotor 5. The muffler passage 16 and the first discharge passage 18 penetrate the closed section 34 from the top surface to the bottom surface.

[0045] As shown in Figure 3, the first discharge passage 18 is formed in an arc shape along the outer edge of the rotor 5. For example, the first discharge passage 18 is formed in a groove shape with a depth greater than its width. If the width of the first discharge passage 18 is small, it becomes easier to secure a seal width, thereby improving the reliability of the seal. Because the first discharge passage 18 is formed deep, the flow path cross-sectional area can be increased, and the flow resistance of the discharge gas can be reduced. For example, the width of the first discharge passage 18 is the radial dimension. For example, the depth of the first discharge passage 18 is the axial dimension.

[0046] As shown in Figures 1 and 3, a plurality of second discharge passages 19 are formed on the upper end surface 17 of the rotor 5. The second discharge passages 19 are formed opening onto the outer circumferential surface of the rotor 5. The plurality of second discharge passages 19 are formed at different positions in the circumferential direction of the rotor 5. The number of second discharge passages 19 may be multiple (any number of two or more) per vane 12. In this embodiment, the number of second discharge passages 19 is two per vane 12. The second discharge passages 19 can connect the first discharge passage 18 to the working chamber 10.

[0047] During the rotation of the rotor 5, the first discharge passage 18 and the second discharge passage 19 are in communication, and when viewed from a direction parallel to the axial direction, they are switched between a communication state and a non-communication state. In other words, the first discharge passage 18 and the second discharge passage 19 are in intermittent communication. The rotation of the rotor 5 causes the communication state and the non-communication state to repeat.

[0048] In the connected state, the first discharge passage 18 and the second discharge passage 19 overlap in at least part when viewed from a direction parallel to the axial direction. In the disconnected state, the first discharge passage 18 and the second discharge passage 19 are positioned circumferentially offset when viewed from a direction parallel to the axial direction. In the disconnected state, the first discharge passage 18 and the second discharge passage 19 do not overlap when viewed from a direction parallel to the axial direction. In the disconnected state, the opening of the first discharge passage 18 is sealed by the upper end surface 17 of the rotor 5. Depending on the position of the rotor 5, in the disconnected state, the opening of the first discharge passage 18 is sealed by the upper end surface 17 of the rotor 5 and the upper end surface of the vane 12.

[0049] In the non-communication state, the opening of the first discharge passage 18 is sealed by the upper end surface 17 of the rotor 5 (or the upper end surfaces of the rotor 5 and the vane 12), thereby preventing the discharge gas in the first discharge passage 18 from flowing back into the working chamber 10, which has not yet reached the discharge pressure.

[0050] As shown in Figure 1, the lower bearing 9 (second bearing) is located below the cylinder 7. The lower bearing 9 has a bearing portion 35 and a closing portion 36. The bearing portion 35 rotatably supports the drive shaft 4 below the cylinder 7. The closing portion 36 closes the opening on the lower side (other end side) of the cylinder chamber 31.

[0051] The muffler 30 is positioned above the closed section 34. A discharge muffler space 14 is formed between the muffler 30 and the upper bearing 8. High-pressure gaseous refrigerant discharged from the muffler communication passage 16 is introduced into the discharge muffler space 14 via the discharge communication passages 18 and 19. The gaseous refrigerant in the discharge muffler space 14 is discharged through the gap between the bearing section 33 and the muffler 30 into the discharge space 15, which is the space inside the sealed case 1.

[0052] As shown in Figure 2, as the rotor 5 rotates together with the drive shaft 4, the refrigerant is drawn from the suction passage 13 into the suction chamber 10a. As the rotor rotates, the vane 12 blocks communication with the suction passage 13, and the suction chamber 10a becomes the compression chamber 10b.

[0053] As the rotor 5 rotates, the compression chamber 10b moves from bottom dead center to top dead center (minimum gap 6), and the volume of the compression chamber 10b decreases. The compression chamber 10b compresses the gaseous refrigerant as its volume decreases.

[0054] As shown in Figure 3, during the process in which the gaseous refrigerant is compressed by the rotation of the rotor 5, the discharge passages 18 and 19 remain disconnected while the compression chamber 10b is at a low pressure, but when the compression chamber 10b becomes high pressure, the discharge passages 18 and 19 become connected. For example, the first discharge passage 18 and the second discharge passage 19 may remain disconnected when the pressure of the gaseous refrigerant in the compression chamber 10b is lower than the pressure outside the cylinder 7, and become connected when the pressure of the gaseous refrigerant in the compression chamber 10b rises to be equal to or higher than the pressure outside the cylinder 7.

[0055] A portion of the refrigerant in the compression chamber 10b is discharged into the discharge space 15 within the sealed case 1 via the discharge passages 18, 19, the muffler passage 16, and the discharge muffler space 14 (see Figure 1). At least a portion of the refrigerant in the compression chamber 10b may also be discharged from the discharge port 22b.

[0056] As shown in Figure 5, it is preferable that the refrigerant in the working chamber 10 is discharged from both the discharge port 22b and the discharge passages 18 and 19 before the vane 12 passes through the discharge port 22b. This reduces the discharge flow rate from the discharge port 22b, making it easier for the discharge valve 22a to close. Therefore, even when the discharge port section 22 communicates with the working chamber 10, which has not yet reached the discharge pressure, after the vane 12 has passed through the discharge port 22b, backflow of the discharged gas can be suppressed. Furthermore, the impact force on the valve seat (regulating member 46) when the discharge valve 22a closes can be reduced.

[0057] As shown in Figure 6, after the vane 12 has passed through the discharge port 22b, it is preferable that the refrigerant in the working chamber 10 is discharged only from the discharge passages 18 and 19, rather than from the discharge port 22b. This reduces the need to form the discharge port 22b in a downstream position. Therefore, the radial distance between the outer surface of the rotor 5 and the inner surface of the cylinder 7 at the discharge port section 22 can be secured. Consequently, the cross-sectional area of ​​the flow path before flowing into the discharge port section 22 becomes larger. Thus, the occurrence of flow path losses can be suppressed.

[0058] In the rotary compressor 102 of this embodiment, since multiple second discharge passages 19 are formed, the flow rate of refrigerant between the discharge space 15 and the working chamber 10 can be adjusted as shown below.

[0059] As shown in Figure 5, when the vane 12 is located upstream of the discharge port 22b (first stage), it is preferable that only one of the multiple second discharge passages 19 communicates with the first discharge passage 18. Depending on the operating conditions, the pressure in the working chamber 10 (compression chamber 10b) may not reach the discharge pressure when the first discharge passage 18 and the second discharge passage 19 are connected. However, by ensuring that only one of the multiple second discharge passages 19 communicates with the first discharge passage 18, the amount of gas flowing back from the discharge space 15 into the working chamber 10 through the discharge passages 18 and 19 can be suppressed.

[0060] As shown in Figure 7, when the vane 12 passes through the discharge port 22b (second stage), it is preferable that multiple second discharge passages 19 communicate with the first discharge passage 18. In this embodiment, two second discharge passages 19 communicate with the first discharge passage 18. That is, a larger number of second discharge passages 19 communicate with the first discharge passage 18 compared to the first stage. This reduces the gas discharge flow rate from the discharge port 22b. As a result, the discharge valve 22a becomes easier to close. Therefore, even when the discharge port section 22 communicates with the working chamber 10, which has not yet reached the discharge pressure, after the vane 12 has passed through the discharge port 22b, gas backflow can be suppressed.

[0061] According to the rotary compressor 102 of this embodiment, during the rotation process of the rotor 5, a connected state in which the first discharge passage 18 and the second discharge passage 19 are in communication and a non-connected state in which the first discharge passage 18 and the second discharge passage 19 are not in communication are switched. When the first discharge passage 18 and the second discharge passage 19 are in communication, the refrigerant is discharged from the working chamber 10 through the discharge passages 18 and 19. In this way, by adjusting the communication between the working chamber 10 and the discharge space 15 using the discharge passages 18 and 19, the refrigerant can be discharged into the discharge space 15 while suppressing the re-expansion of the discharge gas. Therefore, performance degradation, reliability degradation, and manufacturability degradation caused by the discharge valve can be suppressed.

[0062] Specifically, in the rotary compressor 102, gas can be discharged from the discharge passages 18 and 19, which reduces overcompression loss and re-expansion loss compared to using only a discharge valve as the discharge structure. Flow path loss when passing through the discharge valve can also be reduced. In the rotary compressor 102, the load on the discharge valve can be reduced compared to using only a discharge valve, thus reducing the risk of discharge valve damage and ensuring reliability. Furthermore, because the load on the discharge valve can be reduced, it is possible to avoid a decrease in manufacturability due to the increased complexity of the discharge valve's processing.

[0063] The refrigeration cycle device 100 according to this embodiment includes a rotary compressor 102, a heat sink, an expansion device 105, and a heat absorber. The rotary compressor 102 can suppress performance degradation, reliability degradation, and manufacturability degradation caused by the discharge valve. Because the refrigeration cycle device 100 has a rotary compressor 102, its performance as a refrigeration cycle device can be improved.

[0064] (Second embodiment) A rotary compressor according to the second embodiment will now be described. Figures 8 and 9 are cross-sectional views of the rotary compressor according to the second embodiment. Components common to the rotary compressor 102 according to the first embodiment are denoted by the same reference numerals and their description is omitted.

[0065] As shown in Figure 8, in the rotary compressor according to this embodiment, an injection circuit 24 is formed in the cylinder 7. The injection circuit 24 injects intermediate-pressure refrigerant into the working chamber 10.

[0066] An injection communication passage 25 is formed in the closed portion 34 (see Figure 1) of the upper bearing 8. The injection communication passage 25 communicates with the injection circuit 24. The lower end of the injection communication passage 25 opens to the lower surface of the closed portion 34. The lower end of the injection communication passage 25 opens toward the upper end surface 17 of the rotor 5.

[0067] As shown in Figure 9, during the rotation process of the rotor 5, the second discharge passage 19 intermittently communicates with the injection passage 25. In this rotary compressor, the intermediate-pressure refrigerant is introduced into the working chamber 10 by the second discharge passage 19 communicating with the injection passage 25.

[0068] In the rotary compressor according to this embodiment, since an injection circuit 24 and an injection communication passage 25 are formed, intermediate-pressure refrigerant can be introduced into the working chamber 10 using the second discharge communication passage 19. This rotary compressor has the advantage of simplifying the structure because it can introduce intermediate-pressure refrigerant without newly forming a dedicated flow path for the intermediate-pressure refrigerant.

[0069] In the example shown in Figure 5, when the vane 12 is on the upstream side (first stage), one of the two second discharge passages 19 communicates with the first discharge passage 18, but the number of second discharge passages communicating with the first discharge passage (number of connections) is not particularly limited. There may be multiple second discharge passages. It is sufficient if only some of the multiple second discharge passages communicate with the first discharge passage.

[0070] In the example shown in Figure 7, when the vane 12 passes through the discharge port 22b (second stage), two of the two second discharge passages 19 communicate with the first discharge passage 18. However, the number of second discharge passages communicating with the first discharge passage (number of connections) is not particularly limited. The number of second discharge passages communicating only needs to be greater than the number of connections when the vane 12 is on the upstream side (first stage).

[0071] In the rotary compressor according to the embodiment, in addition to the above-described configuration, a third discharge passage having the same configuration as the first discharge passage 18 (see Figure 1) may be formed in the closed portion of the lower bearing, and a fourth discharge passage having the same configuration as the second discharge passage 19 (see Figure 1) may be formed in the rotor. The number of second discharge passages may be one per vane, or multiple (any number of two or more) per vane.

[0072] According to at least one embodiment described above, during the rotation process of the rotor 5, a connected state in which the first discharge passage 18 and the second discharge passage 19 are in communication and a non-connected state in which the first discharge passage 18 and the second discharge passage 19 are not in communication are switched. When the first discharge passage 18 and the second discharge passage 19 are in communication, the refrigerant is discharged from the working chamber 10 through the discharge passages 18 and 19. In this way, by adjusting the communication between the working chamber 10 and the discharge space 15 using the discharge passages 18 and 19, the refrigerant can be discharged into the discharge space 15 while suppressing the re-expansion of the discharged gas. Therefore, performance degradation, reliability degradation, and manufacturability degradation caused by the discharge valve can be suppressed.

[0073] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents. [Explanation of symbols]

[0074] 1...Sealed case (case), 2...Electric motor (drive element), 3...Compression mechanism (compression element), 4...Drive shaft, 5...Rotor, 6...Minimum gap, 7...Cylinder, 8...Upper bearing (end plate), 10...Operating chamber, 12...Vane, 13...Suction passage, 17...Upper end face (end face), 18...First discharge passage, 19...Second discharge passage, 21...Recess, 22...Discharge port section, 22a...Discharge valve, 22b...Discharge port, 24...Injection circuit, 25...Injection passage, 31...Cylinder chamber, 100...Refrigeration cycle device, 102...Rotary compressor, 104...First heat exchanger (radiator, heat absorber), 105...Expansion device, 106...Second heat exchanger (radiator, heat absorber)

Claims

1. The case and The drive shaft housed in the aforementioned case, A drive element that rotates the aforementioned drive shaft, A compression element for compressing the working fluid, The aforementioned compression element is A cylinder in which an opening at one end is closed by an end plate to form a cylinder chamber, A cylindrical rotor that rotates within the cylinder, The rotor has a plurality of vanes that are able to move back and forth in the radial direction, The cylinder chamber is formed between the inner circumferential surface of the cylinder and the outer circumferential surface of the rotor. A minimum gap is formed in the cylinder chamber such that the distance between the inner surface of the cylinder and the outer surface of the rotor is minimized. The vane divides the cylinder chamber into an operating chamber, The working chamber changes its volume in accordance with the rotation of the rotor, thereby drawing in the working fluid on the upstream side, compressing the working fluid, and discharging it on the downstream side. A first discharge passage is formed in the end plate, facing the end face of the rotor. A second discharge passage is formed in the rotor, which connects the first discharge passage and the working chamber. During the rotation process of the rotor, the first discharge passage and the second discharge passage are switched between a connected state in which they are in communication and a disconnected state in which they are not in communication. The first discharge passage and the second discharge passage are in communication, so that the working fluid is discharged from the working chamber through the first discharge passage and the second discharge passage. Rotary compressor.

2. The first discharge passage is arc-shaped along the outer edge of the rotor and has a groove-like shape with a depth greater than its width. The opening of the first discharge passage is sealed by the end face of the rotor and the end face of the vane in the non-communication state. The rotary compressor according to claim 1.

3. When viewed from a direction parallel to the drive shaft, a recess is formed on the inner circumferential surface of the cylinder facing the second discharge passage, which is concave toward the radially outward direction of the rotor. The recess forms a flow space through which the working fluid discharged from the working chamber can flow. The rotary compressor according to claim 1.

4. The cylinder has a discharge port that opens and closes by a discharge valve, which opens and closes on the inner surface. The working fluid in the working chamber is discharged from both the discharge port and the first and second discharge passages before the vane passes through the discharge port. After the vane has passed the discharge port, the working fluid in the working chamber is discharged only from the first and second discharge passages among the first and second discharge passages, respectively. The rotary compressor according to claim 1.

5. The system has multiple second discharge passages, In the first stage, when the vane is located away from the discharge port, only a portion of the plurality of second discharge passages communicates with the first discharge passage. In the second stage, in which the vanes pass through the discharge port, a larger number of the second discharge passages than in the first stage are in communication with the first discharge passage. The rotary compressor according to claim 4.

6. The cylinder is provided with an injection circuit for injecting intermediate-pressure refrigerant into the working chamber. An injection communication passage is formed in the end plate, which communicates with the injection circuit and opens toward the end face of the rotor. The second discharge passage communicates with the injection passage, thereby allowing the intermediate-pressure refrigerant to flow into the working chamber. The rotary compressor according to claim 1.

7. A rotary compressor according to any one of claims 1 to 6, A heat sink connected to the rotary compressor, An expansion device connected to the aforementioned heat sink, The device comprises a heat absorber connected to the aforementioned expansion device. Refrigeration cycle device.

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