Scroll Compressor

Abstract

A scroll compressor is provided that can ensure oil supply to an Oldham ring and suppress a decrease in compression efficiency under low pressure ratio conditions. [Solution] The scroll compressor 100 comprises an orbiting scroll 1 having a spiral orbiting wrap 1a, a fixed scroll 2 having a spiral fixed wrap 2a, a frame 5 supporting the fixed scroll 2, a suction chamber 12 that draws in refrigerant, a compression chamber 3 formed between the orbiting wrap 1a and the fixed wrap 2a and compressing the refrigerant, a back pressure chamber 6 formed between the orbiting scroll 1 and the frame 5, compression side communicating passages 8a, 8b that intermittently connect the compression chamber 3 and the back pressure chamber 6, and a suction side communicating passage 13 for intermittently connecting the suction chamber 12 and the back pressure chamber 6, and the communication timing of the suction side communicating passage 13 differs from the communication timing of the compression side communicating passage.

Description

[Technical Field]

[0001] The present disclosure relates to scroll compressors. [Background technology]

[0002] Computer air conditioning compressors and VRF compressors are required to operate under low pressure ratio conditions. When operating under low pressure ratio conditions, the pressure difference between the back pressure chamber pressure and the discharge pressure tends to be small. If this pressure difference is small, it becomes difficult to supply oil to the Oldham ring.

[0003] Patent Document 1 discloses a scroll compressor equipped with a passageway opening and closing means for connecting the back pressure chamber and the suction chamber when the pressure difference between the back pressure chamber pressure and the discharge pressure falls below the pressure difference (oil supply differential pressure) required to supply oil to the Oldham ring. When the oil supply differential pressure becomes small, the opening and closing means opens, releasing the pressure in the back pressure chamber to the suction chamber, thereby ensuring the oil supply differential pressure to the Oldham ring.

[0004] The scroll compressor has a small hole provided in the end plate of the orbiting scroll, and this small hole is connected to a back pressure chamber formed by the orbiting scroll and the frame. As a result, the gas refrigerant inside the scroll is guided to the back pressure chamber, and a pushing force is applied to the back surface of the orbiting scroll by the gas refrigerant at an intermediate pressure (a pressure between the suction pressure (low-pressure side pressure) and the discharge pressure), which counters the thrust force (a repulsion force that tries to push the orbiting scroll downward) caused by the compression pressure in the multiple compression chambers formed by the orbiting scroll and the fixed scroll. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Special Publication No. 6-1073 Summary of the Invention [Problem to be solved by the invention]

[0006] The valve element, which is the opening and closing means of the scroll compressor, is open when the pressure in the back pressure chamber is greater than the discharge pressure (under operating conditions resulting in a low pressure ratio), and the gas refrigerant in the back pressure chamber flows into the suction chamber regardless of the crank angle. As a result, the gas refrigerant may flow into the back pressure chamber through pores during compression and then flow from the back pressure chamber into the suction chamber, which may reduce compression efficiency.

[0007] An object of the present disclosure is to provide a scroll compressor that can ensure oil supply to an Oldham ring and suppress a decrease in compression efficiency under low pressure ratio conditions. [Means for solving the problem]

[0008] The scroll compressor of the present disclosure comprises an orbiting scroll having a spiral orbiting wrap and a fixed scroll having a spiral fixed wrap, a frame supporting the fixed scroll, a suction chamber that draws in refrigerant, a compression chamber formed between the orbiting wrap and the fixed wrap and that compresses the refrigerant, a back pressure chamber formed between the orbiting scroll and the frame, a compression side communicating passage that intermittently connects the compression chamber and the back pressure chamber, and a suction side communicating passage for intermittently connecting the suction chamber and the back pressure chamber, and the communication timing of the suction side communicating passage differs from the communication timing of the compression side communicating passage. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a view showing a part of a vertical cross section of a scroll compressor according to one embodiment. [Figure 2] FIG. 2 is a bottom view showing a fixed scroll of the scroll compressor according to the embodiment. [Figure 3] FIG. 3 is a view showing a part of a vertical cross section of the scroll compressor according to the embodiment. [Figure 4] FIG. 4 is a view showing a part of a vertical cross section of the scroll compressor according to the embodiment. [Figure 5] FIG. 5 is an enlarged view of the valve body portion of FIG. [Figure 6]FIG. 6 is a view showing a part of a vertical cross section of a scroll compressor according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] A scroll compressor 100 according to one embodiment will be described with reference to Figures 1 to 5. Note that in each figure, the dimensional ratios in the drawing do not necessarily match the actual dimensional ratios, and the dimensional ratios between the drawings do not necessarily match either. Figures 1, 3, and 4 are views showing a portion of the vertical cross section of the scroll compressor 100, Figure 2 is a bottom view showing the fixed scroll 2 of the scroll compressor 100, and Figure 5 is an enlarged view of the valve body 16 portion of Figure 1.

[0011] As shown in Fig. 1, a scroll compressor 100 (hereinafter also simply referred to as "compressor 100") is configured to be able to compress a refrigerant. The compressor 100 is used, for example, in large commercial air conditioners such as VRFs and air conditioners for computers.

[0012] The compressor 100 includes a sealed container (not shown), an orbiting scroll 1, a fixed scroll 2, a frame 5, an Oldham ring 11, a crankshaft (not shown), and an electric motor (not shown).

[0013] The sealed container is a cylindrical container that houses the orbiting scroll 1, the fixed scroll 2, the frame 5, the Oldham ring 11, the crankshaft, the electric motor, etc. The sealed container is filled with lubricating oil to enhance the lubrication of the compressor 100, and the lubricating oil is stored as an oil reservoir at the bottom of the sealed container.

[0014] The sealed container includes a cylindrical chamber, a lid chamber fixed to the top of the cylindrical chamber, and a bottom chamber fixed to the bottom of the cylindrical chamber. A suction pipe (not shown) is inserted and fixed into the lid chamber of the sealed container. The suction pipe is a pipe that guides refrigerant to a suction chamber 12 (described later). A discharge pipe (not shown) is inserted and fixed into the cylindrical chamber of the sealed container. The discharge pipe is a pipe that guides gaseous refrigerant (also referred to as gas refrigerant) compressed in a compression chamber 3 (described later) to the outside of compressor 100.

[0015] The crankshaft is a shaft that rotates integrally with the rotor of the electric motor and extends in the vertical direction. The crankshaft is fixed coaxially to the rotor of the electric motor. An oil supply passage through which lubricating oil flows is provided inside the crankshaft, and the oil supply passage extends in the vertical direction. The oil supply passage is immersed in lubricating oil collected in an oil sump, and the lubricating oil flows (is sucked up) through the oil supply passage due to the pressure difference (oil supply differential pressure) between the discharge pressure and the pressure in the back pressure chamber 6 described below. The lubricating oil that reaches the top of the oil supply passage is supplied to the Oldham ring 11, crankshaft bearings, etc.

[0016] The electric motor is a drive source that rotates the crankshaft and is provided below the frame 5. The electric motor includes a stator and a rotor. The stator is a cylindrical member made of laminated electromagnetic steel sheets and is fixed to the inner peripheral wall of the cylindrical chamber. The rotor is a cylindrical member made of laminated electromagnetic steel sheets and is disposed radially inside the stator. The rotor is fixed to the crankshaft by press-fitting or the like.

[0017] The orbiting scroll 1 and the fixed scroll 2 are provided in the upper space inside the sealed container. The fixed scroll 2 is a fixed member fixed inside the sealed container, and the orbiting scroll 1 is a moving (orbiting) member that forms a compression chamber 3 between itself and the fixed scroll 2 as it orbits.

[0018] The orbiting scroll 1 is provided between the fixed scroll 2 and the frame 5. The orbiting scroll 1 includes a spiral orbiting wrap 1a, a disk-shaped orbiting base plate 1b, and a boss portion (not shown) that is fitted onto the upper end of the crankshaft. The orbiting wrap 1a is provided upright above the orbiting base plate 1b.

[0019] The fixed scroll 2 includes a spiral-shaped fixed wrap 2a and a thick, disc-shaped fixed base plate 2b. The fixed wrap 2a is erected below the fixed base plate 2b. A suction chamber 12 having a suction port through which gas refrigerant is drawn from a suction pipe is provided on the peripheral edge of the fixed base plate 2b. A discharge port is provided in the center of the fixed base plate 2b of the fixed scroll 2, through which gas refrigerant compressed in the compression chamber 3 is guided to an upper space within the sealed container.

[0020] The compression chamber 3 is a space formed between the orbiting wrap 1a and the fixed wrap 2a by meshing them together, and is a space for compressing the gas refrigerant. The compression chamber 3 consists of an outer line chamber 3a formed on the outer line side of the orbiting wrap 1a, and an inner line chamber 3b formed on the inner line side of the orbiting wrap 1a.

[0021] The frame 5 is a member that supports the fixed scroll 2 and fixes the bearing of the crankshaft. The frame 5 is formed in a substantially rotationally symmetrical shape and is fixed to the inner peripheral wall of the cylindrical chamber of the sealed container. The frame 5 is provided with an insertion hole through which the crankshaft is inserted.

[0022] The Oldham ring 11 is a ring-shaped member that receives the rotation of the crankshaft and orbits the orbiting scroll 1 without rotating on its axis. The Oldham ring 11 is provided between the orbiting scroll 1 and the frame 5.

[0023] When the orbiting scroll 1 is rotated by the motor, the volume of the compression chambers 3 formed one after another decreases, compressing the gas refrigerant. The compressed gas refrigerant is discharged into the upper space in the sealed container through the discharge port of the fixed scroll 2, and then flows into the space below the frame 5 through the gap between the frame 5 and the cylindrical chamber. Therefore, the space above the fixed scroll 2 and the space below the frame 5 are each filled with gaseous refrigerant at a pressure substantially equal to the discharge pressure. The gas refrigerant that flows into the space below the frame 5 is discharged to the outside of the compressor 100 through the discharge pipe.

[0024] A back pressure chamber 6 is formed between the orbiting scroll 1 and the frame 5. A gas refrigerant at an intermediate pressure (a pressure between the suction pressure and the discharge pressure) is sealed in the back pressure chamber 6, and applies an upward force to the back surface 10 (lower surface) of the orbiting scroll 1. This counteracts the thrust force caused by the compression pressure in the compression chamber 3, reduces leakage loss from the tooth tips of the orbiting wrap 1a, and suppresses a decrease in compression efficiency. The pressure in the back pressure chamber 6 is determined by the positions of compression-side communication passages 8a and 8b (see FIG. 2), which will be described later. In FIG. 1, the back pressure chamber 6 on the side of the orbiting scroll 1 and the back pressure chamber 6 below the orbiting scroll 1 are depicted as not being connected, but in reality they are connected by a groove (not shown) or the like.

[0025] 2 to 4, the orbiting scroll 1 is provided with a first compression side communication passage 8a and a second compression side communication passage 8b that intermittently communicate between the compression chamber 3 and the back pressure chamber 6. The chain line in FIG. 2 indicates the orbiting scroll 1.

[0026] The first compression-side communication passage 8a intermittently connects the external line chamber 3a in the compression chamber 3 to the back pressure chamber 6, and the second compression-side communication passage 8b intermittently connects the internal line chamber 3b in the compression chamber 3 to the back pressure chamber 6. This makes it possible to supply lubricating oil to both the external line chamber 3a and the internal line chamber 3b. Figure 3 shows a state in which the external line chamber 3a (compression chamber 3) and the back pressure chamber 6 are connected via the first compression-side communication passage 8a, while Figures 2 and 4 show a state in which the external line chamber 3a (compression chamber 3) and the back pressure chamber 6 are not connected.

[0027] The first compression-side communication passage 8a is provided closer to the periphery of the orbiting scroll 1 than the second compression-side communication passage 8b. The compression-side communication passages 8a, 8b are formed, for example, with a substantially U-shaped cross section. The compression-side communication passages 8a, 8b have two openings on the upper surface of the orbiting scroll 1. One opening communicates with the compression chamber 3, and the other opening communicates with a fixed-side back pressure groove 9 provided on the lower surface of the fixed scroll 2.

[0028] The fixed-side back pressure groove 9 consists of an annular groove 9a provided on the circumferential edge side of the fixed scroll 2 and an extended groove 9b extending from the annular groove 9a toward the center of the fixed scroll 2. The annular groove 9a and the extended groove 9b communicate with the back pressure chamber 6. The opening on the other side of each compression-side communicating passage 8a, 8b intermittently communicates with the extended groove 9b, and the communication timings differ.

[0029] When the crank angle of the crankshaft is in a first compression side communication range, the compression chamber 3 (external line chamber 3a) and the back pressure chamber 6 (fixed side back pressure groove 9) communicate with each other via the first compression side communication passage 8a (state shown in FIG. 3 ). When the crank angle is in a second compression side communication range, the compression chamber 3 (internal line chamber 3b) and the back pressure chamber 6 (fixed side back pressure groove 9) communicate with each other via the second compression side communication passage 8b. The first compression side communication range is, for example, a range of 120 to 240 degrees per rotation, and the second compression side communication range is, for example, a range of 0 to 20 degrees and 270 to 360 degrees per rotation. During the rotation of the crankshaft, the first compression side communication range does not overlap with the second compression side communication range.

[0030] 1 and 5, the fixed scroll 2 is provided with a suction-side communication passage 13 for intermittently communicating the suction chamber 12 with the back pressure chamber 6. The suction-side communication passage 13 intermittently communicates with an orbiting-side back pressure groove 14 provided on the periphery of the top surface of the orbiting scroll 1. The orbiting-side back pressure groove 14 communicates with the back pressure chamber 6. FIG. 1 shows a state in which the suction chamber 12 and the back pressure chamber 6 are in communication with each other via the suction-side communication passage 13, while FIG. 5 shows a state in which the suction chamber 12 and the back pressure chamber 6 are not in communication with each other.

[0031] The communication timing of the suction side communication passage 13 is different from the communication timing of the compression side communication passages 8a, 8b (see FIG. 2). With this configuration, by differentiating the communication timing of the suction side communication passage 13 from the communication timing of the compression side communication passages 8a, 8b, it is possible to prevent communication between the compression chamber 3 and the suction chamber 12 via the back pressure chamber 6. This prevents gas refrigerant from flowing from the compression chamber 3 into the suction chamber 12 via the back pressure chamber 6, and suppresses a decrease in the compression efficiency of the compressor 100. In addition, an oil supply differential pressure, which is the pressure difference between the discharge pressure and the pressure in the back pressure chamber 6, is ensured, making it possible to supply lubricating oil to the Oldham ring 11, etc.

[0032] When the crank angle of the crankshaft is within the suction side communication range, the suction chamber 12 and the back pressure chamber 6 communicate with each other via the suction side communication passage 13. The suction side communication range is, for example, a range of 85 to 110 degrees per rotation. The suction side communication range is smaller than the compression side communication range (the sum of the first and second compression side communication ranges). During rotation of the crankshaft, the suction side communication range does not overlap with the first and second compression side communication ranges. The suction side communication range, the first compression side communication range, and the second compression side communication range are not limited to the above and can be set appropriately within ranges where they do not overlap.

[0033] As shown in Fig. 5, the compressor 100 includes a valve element 16 that opens and closes the suction side communicating passage 13 and a spring 15 that biases the valve element 16 in a direction that opens the valve element 16. The valve element 16 is preferably positioned so that the pressure in the back pressure chamber 6 acts on one end (upper end) and the discharge pressure acts on the other end (lower end). With this configuration, when the discharge pressure is lower than the back pressure, the gas refrigerant in the back pressure chamber 6 pushes up the valve element 16 when the suction side communicating passage 13 is opened, causing the gas refrigerant in the back pressure chamber 6 to flow into the suction chamber 12, thereby reducing the pressure in the back pressure chamber 6. When the pressure in the back pressure chamber 6 drops to a predetermined value, the discharge pressure pushes down the valve element 16, closing the suction side communicating passage 13. This ensures an oil supply differential pressure, which is the pressure difference between the discharge pressure and the pressure in the back pressure chamber 6, enabling the supply of lubricating oil to the Oldham ring 11, etc.

[0034] The valve body 16 and the spring 15 are provided in a valve chamber 22 that communicates with the suction chamber 12. The valve chamber 22 is formed in a cylindrical shape and is provided on the peripheral edge side of the fixed scroll 2 rather than the suction chamber 12. The valve body 16 is formed in a cylindrical shape having an outer diameter slightly smaller than the inner diameter of the valve chamber 22. The valve chamber 22 and the suction chamber 12 communicate with each other through a valve chamber communication passage 19 provided in the fixed scroll 2. The valve chamber communication passage 19 extends upward and obliquely toward the peripheral edge side (valve chamber 22 side) of the fixed scroll 2.

[0035] A reduced diameter portion 16b (or a notch portion) is provided on the other end (lower end) side of the valve body 16. The reduced diameter portion 16b is provided at a position connected to the valve chamber communication passage 19 when the valve body 16 is closed. This enables the valve body 16 to operate even when burrs or the like occur around the opening of the valve chamber communication passage 19.

[0036] The compressor 100 preferably includes a valve retainer 17 that restricts the movement of the valve body 16 in the other end direction (upward direction). The valve retainer 17 is formed, for example, in a cylindrical shape and has a through hole 17a for allowing the gas refrigerant discharged from the discharge port to flow into the valve chamber 22. The spring 15 is, for example, a compression coil spring, and a fitting hole 22a for fitting the spring 15 is provided in the valve chamber 22. The fitting hole 22a communicates with the suction side communication passage 13.

[0037] In order to ensure the oil supply differential pressure, for example, when the oil supply differential pressure becomes less than 0.1 MPa, the valve body 16 opens, and when it becomes 0.1 MPa or more, the valve body 16 closes. The spring constant k of the spring 15, the cross-sectional area A1 of the valve chamber 22, the cross-sectional area A2 of the fitting hole 22a, and the cross-sectional area A of the through hole 17a are set. When the discharge pressure is Pd, the pressure in the back pressure chamber 6 is Pb, and the displacement of the spring 15 is x, the valve body 16 is opened when Pd×A1<Pb×A2+kx is satisfied, and the back pressure chamber 6 and the suction chamber 12 are communicated. On the other hand, when Pd×A3>Pb×A1+kx is satisfied, the valve body 16 is closed, and the back pressure chamber 6 and the suction chamber 12 are not communicated.

[0038] The valve body 16 is preferably provided with a seal member 20 that separates the space where the pressure of the back pressure chamber 6 acts from the space where the discharge pressure acts. This configuration prevents leakage of gas refrigerant from the space where the discharge pressure acts to the space where the pressure of the back pressure chamber 6 acts, thereby suppressing a decrease in compression efficiency. The seal member 20 is, for example, an O-ring, and is fitted into a recessed groove 16a provided on the side peripheral surface of the valve body 16.

[0039] For example, when the pressure ratio is 1.5, the pressure in the back pressure chamber 6 becomes lower than the discharge pressure, so the oil supply differential pressure can be secured. When the pressure ratio is 1.3, the pressure in the back pressure chamber 6 may become higher than the discharge pressure, so the oil supply differential pressure cannot be secured. This may cause poor oil supply to the Oldham ring 11, etc.

[0040] On the other hand, in this embodiment, when the suction side communicating passage 13 is opened, the suction side communicating passage 13 provided near the suction chamber 12 of the fixed scroll 2 communicates with the orbiting-side backpressure groove 14 of the orbiting scroll 1, and gas refrigerant in the backpressure chamber 6 flows into the suction side communicating passage 13. The pressure of the gas refrigerant that has flowed into the suction side communicating passage 13 causes the valve element 16 to move to the valve retainer 17. The gas refrigerant in the backpressure chamber 6 then flows into the suction chamber 12 of the fixed scroll 2 through a valve chamber communicating passage 19 connecting the suction chamber 12, and the pressure in the backpressure chamber 6 decreases. When the pressure in the backpressure chamber 6 decreases to a value that ensures the oil supply differential pressure, the valve element 16 is pushed by the action of the discharge pressure, and the suction side communicating passage 13 is closed. Furthermore, when the suction side communicating passage 13 is connected, the compression side communicating passages 8a, 8b (see FIG. 2) are not connected to the fixed side back pressure groove 9, which prevents refrigerant from leaking from the compression chamber 3 to the suction chamber 12 via the back pressure chamber 6. As a result, even when the pressure ratio is 1.3, the oil supply differential pressure can be ensured, enabling the supply of lubricating oil to the Oldham ring 11 and the like.

[0041] (Variation) In this embodiment, the orbiting scroll 1 is provided with the first compression side communication passage 8a and the second compression side communication passage 8b that intermittently communicate the compression chamber 3 and the back pressure chamber 6, but this is not limited thereto. The orbiting scroll 1 may be provided with only one of the first compression side communication passage 8a and the second compression side communication passage 8b.

[0042] In this embodiment, the suction side communication passage 13 is provided at a position where its suction side communication range does not overlap with the first compression side communication range and the second compression side communication range, thereby differentiating the communication timing of the suction side communication passage 13 from that of the compression side communication passages 8a, 8b, but this is not limiting. For example, the suction side communication passage 13 and the compression side communication passages 8a, 8b may each be provided with an actuator-equipped valve, and the opening and closing timing of each valve may be shifted to differentiate the communication timing of the suction side communication passage 13 from that of the compression side communication passages 8a, 8b.

[0043] Fig. 6 is a view showing a portion of a vertical cross section of a scroll compressor 100 according to another embodiment. As shown in Fig. 6, the fixed scroll 2 may have a step portion 21 provided at the side wall end on the outer circumferential side of the suction chamber 12, and the valve chest communicating passage 19 may communicate with the step portion 21. According to this configuration, the provision of the step portion 21 makes machining easier than when the valve chest communicating passage 19 is provided on the side wall of the suction chamber 12. This improves the productivity of the compressor 100. The step portion 21 may be formed, for example, by countersinking.

[0044] It is preferable that the through hole 17a is provided with an expanded diameter portion 17b that expands in diameter on the valve chamber 22 side. This increases the area on which the discharge pressure acts when the valve element 16 is open (when the valve element 16 is in contact with the valve guard 17). This reduces the difference between the area on which the discharge pressure acts when the valve element 16 is open and the area on which the discharge pressure acts when the valve element 16 is closed.

[0045] [1] As described above, the scroll compressor 100 comprises the orbiting scroll 1 having a spiral-shaped orbiting wrap 1a, the fixed scroll 2 having a spiral-shaped fixed wrap 2a, the frame 5 supporting the fixed scroll 2, the suction chamber 12 that draws in refrigerant, the compression chamber 3 formed between the orbiting wrap 1a and the fixed wrap 2a and compressing the refrigerant, the back pressure chamber 6 formed between the orbiting scroll 1 and the frame 5, the compression side communicating passages 8a, 8b that intermittently connect the compression chamber 3 and the back pressure chamber 6, and the suction side communicating passage 13 for intermittently connecting the suction chamber 12 and the back pressure chamber 6, and the communication timing of the suction side communicating passage 13 differs from the communication timing of the compression side communicating passages 8a, 8b.

[0046] According to this configuration, by differentiating the communication timing of the suction side communication passage 13 from the communication timing of the compression side communication passages 8a, 8b, it is possible to prevent communication between the compression chamber 3 and the suction chamber 12 via the back pressure chamber 6. This prevents refrigerant from flowing from the compression chamber 3 into the suction chamber 12 via the back pressure chamber 6, thereby suppressing a decrease in the compression efficiency of the compressor 100. As a result, it is possible to ensure oil supply to the Oldham ring 11 under low pressure ratio conditions.

[0047] [2] The scroll compressor 100 described in [1] above is preferably configured to include a valve body 16 that opens and closes the suction side communicating passage 13, and a spring 15 that biases the valve body 16 in a direction to open it, and the valve body 16 is preferably arranged in a position where the pressure of the back pressure chamber 6 acts on one end and the discharge pressure acts on the other end.

[0048] With this configuration, when the suction side communicating passage 13 is opened, the gas refrigerant in the back pressure chamber 6 pushes up the valve element 16, the gas refrigerant in the back pressure chamber 6 flows into the suction chamber 12, and the pressure in the back pressure chamber 6 decreases. When the pressure in the back pressure chamber 6 decreases to a predetermined value, the valve element 16 is pushed down by the discharge pressure, and the suction side communicating passage 13 is closed. This ensures an oil supply differential pressure, which is the pressure difference between the discharge pressure and the pressure in the back pressure chamber 6, and enables the supply of lubricating oil to the Oldham ring 11, etc.

[0049] [3] In the scroll compressor 100 described in [2] above, it is preferable that the valve element 16 is provided with a seal member 20 that separates a space where the pressure of the back pressure chamber 6 acts from a space where the discharge pressure acts.

[0050] According to this configuration, leakage of gas refrigerant from the space where the discharge pressure acts to the space where the pressure of the back pressure chamber 6 acts can be prevented, and a decrease in compression efficiency can be suppressed.

[0051] [4] In the scroll compressor 100 described in [2] or [3] above, the fixed scroll 2 may be configured to include a valve chamber 22 in which the valve body 16 is provided, a communication passage (valve chamber communication passage 19) connecting the valve chamber 22 and the suction chamber 12, and a stepped portion 21 provided at the side wall end on the outer circumferential side of the suction chamber 12, and the communication passage (valve chamber communication passage 19) is connected to the stepped portion 21.

[0052] According to this configuration, by providing the step portion 21, machining is easier than when the valve-chamber communication passage 19 is provided in the side wall of the suction chamber 12. This allows the productivity of the compressor 100 to be improved.

[0053] The scroll compressor is not limited to the configuration of the above-described embodiment, nor is it limited to the above-described effects. Furthermore, various modifications can be made to the scroll compressor without departing from the spirit and scope of the present invention. For example, it is possible to select one or more of the configurations, methods, etc. of the various modifications described above and employ them in the configurations, methods, etc. of the above-described embodiment. [Explanation of symbols]

[0054] DESCRIPTION OF SYMBOLS 1...orbiting scroll, 1a...orbiting wrap, 1b...orbiting base plate, 2...fixed scroll, 2a...fixed wrap, 2b...fixed base plate, 3...compression chamber, 3a...external line chamber, 3b...internal line chamber, 5...frame, 6...back pressure chamber, 8a...first compression side communicating passage, 8b...second compression side communicating passage, 9...fixed side back pressure groove, 9a...annular groove, 9b...extended groove, 10...back surface, 11...Oldham ring, 12...suction chamber, 13...suction side communicating passage, 14...orbiting side back pressure groove, 15...spring, 16...valve disc, 16a...recessed groove, 16b...reduced diameter portion, 17...valve guard, 17a...through hole, 17b...expanded diameter portion, 19...valve chamber communicating passage, 20...sealing member, 21...step portion, 22...valve chamber, 22a...fitting hole, 100...scroll compressor

Claims

1. an orbiting scroll having a spiral orbiting wrap; a fixed scroll having a spiral-shaped fixed wrap; a frame supporting the fixed scroll; a suction chamber that draws in a refrigerant; a compression chamber formed between the orbiting wrap and the fixed wrap, the compression chamber compressing the refrigerant; a back pressure chamber formed between the orbiting scroll and the frame; a compression-side communication passage intermittently communicating the compression chamber and the back pressure chamber; an intake-side communication passage for intermittently communicating the intake chamber and the back pressure chamber, the compression chamber connected to the compression-side communication passage is located closer to the inner line of the orbiting wrap than the suction chamber connected to the suction-side communication passage, A scroll compressor, wherein a communication timing of the suction side communication passage is different from a communication timing of the compression side communication passage.

2. a valve body that opens and closes the suction side communication passage; and a spring that biases the valve body in a direction that opens the valve body, 2. The scroll compressor according to claim 1, wherein the valve element is provided at a position where the pressure in the back pressure chamber acts on one end and the discharge pressure acts on the other end.

3. 3. The scroll compressor according to claim 2, wherein the valve body is provided with a seal member that separates a space on which the pressure of the back pressure chamber acts from a space on which the discharge pressure acts.

4. the fixed scroll includes a valve chamber in which the valve element is provided, a communication passage that communicates the valve chamber with the suction chamber, and a step portion that is provided at a side wall end on an outer circumferential side of the suction chamber, The scroll compressor according to claim 2 or 3, wherein the communication passage communicates with the step portion.

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