Scroll compressor and compression gas supply system

Abstract

To provide a scroll compressor capable of reducing the torque loss and the compression ratio loss.SOLUTION: A scroll compressor of the present invention includes a fixed scroll having a first spiral blade on a lower surface of a fixed baseboard, a floating scroll having a second spiral blade on an upper surface of a movable baseboard, and a support frame having an eccentric drive mechanism for revolving the floating scroll and storing the floating scroll in a revolvable state. The first and the second spiral blades are meshed with each other to form a compression chamber, and in the compression chamber which moves while reducing a volume thereof by revolution of the floating scroll so as to perform compression of gas, water is supplied to a portion in a compression process.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a scroll compressor and a compressed gas supply system having the scroll compressor.

Background Art

[0002] A conventional scroll compressor is configured by meshing a first spiral blade provided on the lower surface of a fixed substrate of a fixed scroll and a second spiral blade provided on the upper surface of a movable substrate of a floating scroll. The floating scroll is housed in a support frame in a state where it can revolve. Due to the revolution of the floating scroll, the compression chamber formed between the spiral blades of both scrolls moves while decreasing in volume, thereby compressing the gas.

[0003] By the way, for example, in a compressor for compressing carbon dioxide used as a refrigerant in a refrigeration cycle, the discharge pressure of carbon dioxide becomes very high. Therefore, in a scroll compressor, a very large thrust load based on the pressure in the compression chamber acts on the floating scroll. As a result, the substrate of the floating scroll is strongly biased toward the support frame.

[0004] A technique for buffering the thrust load due to compression to such a high pressure is disclosed in, for example, Patent Document 1. In the scroll compressor described in Patent Document 1, a seal portion is provided between the vicinity of the peripheral edge of the lower surface of the movable substrate and the pedestal portion, and a back pressure chamber is formed in the region surrounded by the seal portion. The intermediate pressure of the gas in the compression process in the compression chamber is taken out and introduced into the back pressure chamber.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, when the back pressure for buffering the thrust load due to compression to high pressure is large, the sliding friction between the floating scroll and the pedestal increases, leading to problems such as torque loss, and thus loss and instability of the compression ratio, and further malfunction.

[0007] Focusing on the above problems, an object of the present invention is to provide a scroll compressor capable of reducing torque loss and loss of compression ratio by reducing the back pressure, and a gas compression system having the scroll compressor.

Means for Solving the Problems

[0008] To achieve the above object, the present invention takes the following means.

[0009] That is, the scroll compressor of the present invention includes a fixed scroll having a configuration in which a first spiral blade is provided on the lower surface of a fixed substrate, a floating scroll having a configuration in which a second spiral blade is provided on the upper surface of a movable substrate, an eccentric drive mechanism for revolving the floating scroll, and a support frame for accommodating the floating scroll in a revolvable state. The first and second spiral blades are engaged with each other to form a compression chamber, and water is supplied to a location in the compression chamber where the compression process is occurring while the volume of the compression chamber decreases as the floating scroll revolves, thereby compressing the gas.

[0010] With such a configuration, since water is supplied to a location in the compression chamber formed by the engagement of the first and second spiral blades with each other, the tip of the first spiral blade of the fixed scroll and the upper surface of the movable substrate of the floating scroll, and the tip of the second spiral blade of the floating scroll and the lower surface of the fixed substrate of the fixed scroll are sealed by a film of water. As a result, the back pressure for buffering the thrust load due to compression to high pressure is reduced, so that torque loss and loss of compression ratio can be reduced.

[0011] In this case, it is preferable that water is supplied to a location in the compression process radially inside an opening through which gas is inhaled into a spiral-shaped closed space formed between the first spiral blade and the second spiral blade.

[0012] With this configuration, even when the drive of the scroll compressor is stopped, it is possible to suppress the water supplied into the compression chamber from flowing out to the outside.

[0013] In this case, it is preferable that the flow rate of water supplied to a location in the compression process is set according to the discharge flow rate of the gas discharged from the compression chamber.

[0014] With this configuration, the flow rate of water supplied to a location in the compression process can be appropriately set.

[0015] In this case, it is preferable that the flow rate of water supplied to a location in the compression process is set according to the volume of the compression chamber.

[0016] With this configuration, the flow rate of water supplied to a location in the compression process can be appropriately set.

[0017] The compressed gas supply system of the present invention is characterized by including the above-described scroll compressor and a water supply mechanism that supplies water to a location in the compression process.

[0018] With this configuration, it is possible to provide a compressed gas supply system capable of reducing torque loss and compression ratio loss.

[0019] In this case, it has a tank to which the compressed gas discharged from the scroll compressor is supplied, and it is preferable that the water supply mechanism supplies the drain water generated in the tank to a location in the compression process.

[0020] With such a configuration, the compressed gas discharged from the scroll compressor contains water vapor, and when the compressed gas is cooled after being supplied into the tank, drain water is generated. Therefore, even without separately securing water to be supplied to a location in the compression process in the scroll compressor, the drain water generated from the water vapor contained in the compressed gas discharged from the scroll compressor can be used. Further, in a compressed gas supply system having a tank to which the compressed gas discharged from the scroll compressor is supplied, the treatment of the drain water generated in the tank becomes a problem. However, by using the drain water as the water to be supplied to a location in the compression process in the scroll compressor, it becomes unnecessary to treat the drain water generated in the compressed gas supply system.

[0021] In this case, it is preferable that the water supply mechanism supplies the drain water to the location in the compression process based on the differential pressure between the gas pressure in the tank and the gas pressure at the location in the compression process.

[0022] With such a configuration, the drain water in the tank can be easily supplied to the location in the compression process.

[0023] In this case, it is preferable that a check valve that allows the flow of water only in the direction from the tank toward the location in the compression process is attached to the pipe that supplies the drain water generated in the tank to the location in the compression process.

[0024] With such a configuration, at the start of compression, when the pressure at the location in the compression process where water is supplied is low, it is possible to prevent the drain water from flowing backward from the location in the compression process to the tank.

Advantages of the Invention

[0025] According to the present invention described above, it is possible to provide a scroll compressor and a compressed gas supply system with reduced losses in torque cross and compression ratio.

Brief Description of the Drawings

[0026]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

MODE FOR CARRYING OUT THE INVENTION

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

[0028] FIG. 1 is a figure which shows the compression gas supply system 500 which has the scroll compressor 100 which concerns on embodiment of this invention. FIG. 2 is a cross-sectional perspective view which shows the scroll compressor 100 of FIG. 1. FIG. 3 is a cross-sectional view of the scroll compressor 100 of FIG. 2. FIG. 4 is a cross-sectional view along line IV-IV in FIG. 3, and FIG. 5 is a cross-sectional view along line V-V in FIG. 3.

[0029] The compressed gas supply system 500 of this embodiment is configured by connecting a scroll compressor 100, a first drain tank 501, a solenoid valve 502, an actuator 503, a second drain tank 504, and an intake chamber 505 with a plurality of pipes.

[0030] First, the configuration of the scroll compressor 100 will be described, and then the configuration of the compressed gas supply system 500 will be described.

[0031] As shown in FIGS. 2 and 3, the scroll compressor 100 of this embodiment has a structure in which a fixed scroll 1 made of, for example, an aluminum alloy and a floating scroll 2 which is a turning scroll also made of an aluminum alloy are combined and held by a support frame 3 also made of an aluminum alloy.

[0032] The fixed scroll 1 is configured by providing first spiral vanes 5 on the lower surface of a fixed substrate 4, and the floating scroll 2 is configured by providing protruding second spiral vanes 7 on the upper surface of a movable substrate 6. The first and second spiral vanes 5 and 7 have a planar shape that can be relatively movably fitted as shown in FIG. 4. The outer peripheral end of the first spiral vane 5 is connected to a cylindrical outer peripheral wall 5a that surrounds the first spiral vane 5, and a spiral closed space is formed. The mutual arrangement of the floating scroll 2 and the fixed scroll 1 is set so that the second spiral vane 7 meshes with the inside of this spiral closed space. By meshing the first spiral vane 5 and the second spiral vane 7, a compression chamber 8 is formed inside the spiral closed space. As the floating scroll 2 revolves, the compression chamber 8 moves while reducing its volume, and the gas inside the compression chamber 8 is compressed.

[0033] An outlet path vertical portion 9 extending vertically upward in the fixed substrate 4 opens into the compression chamber 8 at the center of the fixed scroll 1. The outlet path vertical portion 9 communicates with an outlet path horizontal portion 10 extending horizontally in the fixed substrate 4. The outlet path horizontal portion 10 opens at the peripheral edge of the fixed substrate 4 and a discharge port 11 is provided. The gas compressed in the compression chamber 8 is supplied to the outside from the discharge port 11.

[0034] Although shown only in Fig. 4, an intake passage vertical portion 12 extending vertically upward in the fixed substrate 4 opens at the outer peripheral end of the spiral-shaped closed space formed by the first spiral blade 5 and the cylindrical outer peripheral wall 5a. The intake passage vertical portion 12 communicates with an intake passage horizontal portion 13 extending horizontally in the fixed substrate 4. The intake passage horizontal portion 13 opens at the peripheral edge of the fixed substrate 4, and an intake port 14 is provided. A gas to be compressed, such as air, is supplied to the intake port 14.

[0035] In the middle of the spiral-shaped closed space, a water supply passage vertical portion 101 communicating with a predetermined position of the compression chamber 8 set between the intake passage vertical portion 12 and the discharge passage vertical portion 9 opens. The water supply passage vertical portion 101 communicates with a water supply passage horizontal portion 102 extending horizontally in the fixed substrate 4. The water supply passage horizontal portion 102 opens at the peripheral edge of the fixed substrate 4, and a water supply port 103 is provided. It is preferable that the size of the opening of the water supply passage vertical portion 101 is set so that the amount of water supplied from the water supply passage vertical portion 101 to the compression chamber 8 is appropriate.

[0036] The support frame 3 shown in Figs. 2 and 3 has a pedestal portion 15 and an upper cylindrical portion 16 extending above the pedestal portion 15. The pedestal portion 15 of the support frame 3 is supported by a lower cylindrical portion 17 disposed therebelow. The floating scroll 2 is held on the pedestal portion 15 via an eccentric drive mechanism 104 described later and is revolvable inside the upper cylindrical portion 16, and the upper end portion of the upper cylindrical portion 16 is coupled to the fixed substrate 4.

[0037] The inside of the upper cylindrical portion 16 forms a cylindrical scroll housing hole 18, and a cylindrical outer peripheral wall 5a protruding downward from the fixed substrate 4 of the fixed scroll 1 is fitted above the scroll housing hole 18.

[0038] As shown in FIGS. 2 and 6, an upwardly open annular groove 151a is formed on the upper surface of the pedestal portion 15 inside the scroll accommodation hole 18, and an O-ring seal 151 is embedded to form a seal portion. Inside the seal portion, a partition wall 50 that projects horizontally toward the radially inner side is provided. The partition wall 50 is a plate-like member having a predetermined thickness, and an opening 50a is formed at the center thereof.

[0039] As shown in FIGS. 2 and 6, a rectangular drive hole 19 is provided below the partition wall 50 of the pedestal portion 15. The drive hole 19 includes a pair of first inner walls 19a at one opposed position and a pair of second inner walls 19b at the other opposed position. An eccentric shaft 28 integrally provided at the upper end of the drive shaft 105 is disposed in the drive hole 19.

[0040] As shown in FIGS. 3 and 8, a back pressure introduction path vertical portion 20 that extends vertically downward opens at the peripheral edge of the pedestal portion 15. The back pressure introduction path vertical portion 20 communicates with a back pressure introduction path horizontal portion 21 that extends horizontally in the pedestal portion 15. The back pressure introduction path horizontal portion 21 opens at the peripheral edge of the pedestal portion 15, and a back pressure introduction port 22 is provided.

[0041] As shown in FIG. 8, the upper surface 15x of the pedestal portion 15 inside the O-ring seal 151 is slightly lower than the upper surface 15y of the peripheral edge portion of the pedestal portion 15, and a gap δ is provided between the lower surface of the movable substrate 6 and the upper surface of the pedestal portion 15, forming a pressure chamber 23. The above-described back pressure introduction path vertical portion 20 opens into the pressure chamber 23.

[0042] Outside the O-ring seal 151 surrounding the pressure chamber 23, an oil lubrication mechanism shown in Fig. 8 is provided. This oil lubrication mechanism connects an oil introduction path vertical portion 152a that opens to the upper surface 15y of the peripheral edge of the pedestal portion 15 and an oil introduction path horizontal portion 152b that extends horizontally in the pedestal portion 15. The oil introduction path horizontal portion 152b opens to the peripheral edge of the pedestal portion 15 and is provided with an oil introduction port 152c. At a position facing the outer peripheral end surface of the movable substrate 6 on the inner circumference of the upper cylindrical portion 16 constituting the support frame 3, an oil discharge path horizontal portion (not shown) opens. This oil discharge path extends horizontally and opens to the peripheral edge of the pedestal portion 15, and is provided with an oil discharge port (not shown). The oil discharge port is connected to the oil introduction port 152c and an oil circulation path (not shown).

[0043] As shown in Figs. 5 and 7, the eccentric drive mechanism 104 is configured by connecting between the eccentric shaft 105 provided on the pedestal portion 15 and the movable substrate 6 via an anti-rotation mechanism. Specifically, the anti-rotation mechanism has a linear guide portion 106T disposed in a drive hole 19 provided in the pedestal portion 15 and an eccentric shaft connecting member 108 integrally hanging down from the lower surface of the movable substrate 6. The eccentric shaft connecting member 108 is fitted into the linear guide portion 106.

[0044] The linear guide portion 106T has an intermediate frame body 106 into which the eccentric shaft connecting member 108 is fitted. The intermediate frame body 106 includes a pair of opposed first wall portions 106a and a pair of opposed wall portions 106b opposed along a direction orthogonal thereto. A first linear guide 161a is provided on the outer surface of the first wall portion 106a, and a second linear guide 161b is provided on the inner surface of the pair of opposed second wall portions 106b.

[0045] As shown in FIG. 9, each of the linear guides 161a and 161b has a minute roller 161y disposed in each opening 161x of a thin frame 161 having a ladder shape. The minute roller 106y is axially attached to the frame 161 about an axis orthogonal to the arrangement direction of the openings 106x, and is detachably attached to the corresponding wall portions 106a and 106b of the intermediate frame body 106 under an appropriate engagement structure. Grease is applied to the axially attached portion of the minute roller 161y.

[0046] The eccentric shaft connecting member 108 in the shape of a rectangular block into which the intermediate frame body 106 is fitted includes a pair of opposing first wall portions 108a and a pair of opposing wall portions 108b opposing along a direction orthogonal thereto.

[0047] As shown in FIG. 5, on the inner circumference of the intermediate frame body 106, the eccentric shaft connecting member 108 is mounted such that its first outer wall 108a faces the first wall portion 106a of the intermediate frame body 106 and its second outer wall 108b faces the second wall portion 106b of the intermediate frame body 106. Specifically, the first outer wall 108a is loosely fitted to the first wall portion 106a of the intermediate frame body 106, and the second outer wall 108b is closely mounted to the second wall portion 106b of the intermediate frame body 106 via the second linear guide 161b. The eccentric shaft connecting member 108 has a bearing 107 for mounting an eccentric shaft 28 on its inner circumference.

[0048] Then, the intermediate frame body 106 is mounted with respect to the drive hole 19 such that the first inner wall 19a faces the first wall portion 106a and the second inner wall 19b faces the second wall portion 106b. Specifically, the first wall portion 106a is closely mounted to the first inner wall 19a via the first linear guide 161a, and the second wall portion 106b is loosely fitted to the second inner wall 19b.

[0049] When the intermediate frame 106 of the linear guide portion 106T is connected to the eccentric shaft 28 via the eccentric shaft connecting member 108 by the eccentric drive mechanism 104 configured as described above, the intermediate frame 106 is movable in the X direction along the first linear guide 161a with respect to the pedestal 15 as shown in FIGS. 7(a) to (d) (particularly FIGS. 7(a) and (c)), and the eccentric shaft connecting member 108 is movable in the Y direction along the second linear guide 161b with respect to the intermediate frame 106 as shown in FIGS. 7(a) to (d) (particularly FIGS. 7(b) and (d)). By combining these operations, the eccentric shaft connecting member 108 can move freely in the X-Y plane without rotating with respect to the pedestal 15. When the axis of the drive shaft 15 is Ta and the axis of the eccentric shaft 28 is Tb, when the eccentric shaft 28 rotates around the axis AT of the drive shaft 15, accordingly, the eccentric shaft connecting member 108 can revolve without rotating the floating scroll 2 while following the turning of the eccentric shaft 28.

[0050] As shown in FIG. 3, a bearing 171 for supporting the drive shaft 15 is arranged on the support member 3a, and the lower end of the drive shaft 15 is connected to a motor output shaft 180 protruding from the motor box.

[0051] The structure of the support frame 3 of the scroll compressor 100 of the present embodiment will be described with reference to FIG. 10. FIG. 10(a) is a perspective view of the support frame 3 seen from an upper oblique direction, and FIG. 10(b) is a perspective view of the support frame 3 seen from a lower oblique direction.

[0052] As described above, the support frame 3 has a pedestal portion 15 and an upper cylindrical portion 16 extending upward therefrom. As shown in Fig. 10(a), a cylindrical scroll accommodation hole 18 is formed inside the upper cylindrical portion 16 of the support frame 3. An annular groove 151a opened upward is formed on the upper surface of the pedestal portion 15 inside the scroll accommodation hole 18, and an O-ring seal 151 is embedded therein. Inside the seal portion, a partition wall 50 protruding horizontally inward in the radial direction is provided. Below the partition wall 50 of the pedestal portion 15, a rectangular drive hole 19 is provided as shown in Fig. 10(b). The drive hole 19 includes a pair of first inner walls 19a at one opposed position and a pair of second inner walls 19b at the other opposed position.

[0053] When assembling the scroll compressor 100 of the present embodiment, as shown in Fig. 11, after the O-ring seal 151 is embedded in the annular groove 151a of the upper cylindrical portion 16 from above the support frame 3, the floating scroll 2 is disposed in the scroll accommodation hole 18 of the upper cylindrical portion 16 from above the support frame 3. Further, the linear guide portion 106T is disposed in the drive hole 19 of the pedestal portion 15 from below the support frame 3. At this time, the linear guide portion 106T is fitted to the eccentric shaft connecting member 108 of the floating scroll 2.

[0054] Thereby, the lower surface of the movable substrate 6 of the floating scroll 2 comes into contact with the upper surface of the partition wall 50 of the pedestal portion 15. Also, the upper surface of the linear guide portion 106T (intermediate frame body 106) comes into contact with the lower surface of the partition wall 50 of the pedestal portion 15. Therefore, the partition wall 50 of the pedestal portion 15 is disposed between the lower surface of the movable substrate 6 of the floating scroll 2 and the upper surface of the linear guide portion 106T (intermediate frame body 106). Thus, the lower surface of the movable substrate 6 of the floating scroll 2 and the upper surface of the linear guide portion 106T (intermediate frame body 106) are configured not to contact each other.

[0055] In a conventional scroll compressor 500, when the movable substrate 506 of the floating scroll 502 moves within the scroll housing hole 518, the end face of the movable substrate 506 approaches the wall surface of the scroll housing hole 518 in the traveling direction thereof. Then, in the conventional scroll compressor 500, since the lower surface of the movable substrate 506 and the upper surface of the linear guide portion 606T are in contact with each other, the gas between the end face of the movable substrate 506 and the wall surface of the scroll housing hole 518 cannot flow out to the outside. Therefore, the gas is compressed between the end face of the movable substrate 506 and the wall surface of the scroll housing hole 518. As a result, the conventional scroll compressor 500 vibrates greatly, and the quietness characteristics deteriorate.

[0056] On the other hand, in the scroll compressor 100 of the present embodiment, the lower surface of the movable substrate 6 and the upper surface of the linear guide portion 106T are not in contact with each other. Therefore, even when the movable substrate 6 of the floating scroll 2 moves within the scroll housing hole 18 and the end face of the movable substrate 6 approaches the wall surface of the scroll housing hole 18, the gas in the space between the end face of the movable substrate 6 in the traveling direction of the movable substrate 6 and the wall surface of the scroll housing hole 18 flows out through the gap between the lower surface of the movable substrate 6 and the upper surface of the linear guide portion 106T to the space between the end face of the movable substrate 6 on the side opposite to the traveling direction of the movable substrate 6 and the wall surface of the scroll housing hole 18. Therefore, even when the movable substrate 6 of the floating scroll 2 moves within the scroll housing hole 18, it is possible to prevent the gas from being compressed between the end face of the movable substrate 6 and the wall surface of the scroll housing hole 18. As a result, it is possible to suppress the large vibration of the scroll compressor 100 of the present embodiment and improve the quietness characteristics.

[0057] The operation of the scroll compressor 100 having the above configuration is as follows. That is, the rotation of the motor output shaft 180 is transmitted to the eccentric shaft 28 via the drive shaft 105, and the axis Tb of the eccentric shaft 28 orbits around the axis Ta of the drive shaft 105. As a result, the eccentric shaft connecting member 108 attached to the eccentric shaft 28 via the bearing 107 follows the axis Tb of the eccentric shaft 28 and revolves around the axis Ta of the drive shaft 105 in the drive hole 19 via the second linear guide 161b, the frame-shaped member 106, and the first linear guide 161a without rotating. As a result, the floating scroll 2 integrated with the eccentric shaft connecting member 108 also revolves without rotating, and due to this revolving motion, gas is compressed in the compression chamber 8 based on the action of the well-known scroll compressor 100.

[0058] A compression gas supply system 500 having the scroll compressor 100 of the present embodiment will be described. Note that in FIG. 1, the illustration of the scroll compressor 100 is simplified.

[0059] As shown in FIG. 1, the discharge port 11 of the scroll compressor 100 is connected to the first drain tank 501 via the pipe 510. The upper part of the first drain tank 501 is connected to the solenoid valve 502 via the pipe 511. The solenoid valve 502 is connected to the upper space formed in the upper part of the actuator 503 via the pipe 512 and is also connected to the lower space formed in the lower part of the actuator 503 via the pipe 513. Further, the solenoid valve 502 is connected to the second drain tank 504 via the pipe 514. The second drain tank 504 is connected to the intake chamber 505 via the pipe 515. The intake chamber 505 is connected to the intake port 14 of the scroll compressor 100 via the pipe 516.

[0060] Also, a pipe 517 branches from an intermediate portion 511a of the pipe 511 connected to the first drain tank 501, and the pipe 517 is connected to the back pressure introduction port 22 of the scroll compressor 100.

[0061] Furthermore, the lower part of the first drain tank 501 is connected to the water supply port 103 of the scroll compressor 100 via a pipe 518. In this embodiment, the first drain tank 501 and the pipe 518 constitute a water supply mechanism T that supplies water to a location in the compression process of the scroll compressor 100.

[0062] Note that two pressure control valves 506a and 506b for controlling the amount of gas flowing from the first drain tank 501 toward the back pressure introduction port 22 of the scroll compressor 100 are attached to the pipe 517.

[0063] A check valve 531 that allows gas flow only in the direction from the first drain tank 501 toward the solenoid valve 502 is attached to the pipe 511 (specifically, on the downstream side of the portion 511a where the pipe 517 branches). Also, a check valve 532 that allows gas flow only in the direction from the second drain tank 504 toward the intake chamber 505 is attached to the pipe 515. Further, a check valve 533 that allows the flow of drain water only in the direction from the first drain tank 501 toward the water supply port 103 of the scroll compressor 100 is attached to the pipe 518.

[0064] The gas flow in the compression gas supply system 500 of this embodiment will be described.

[0065] First, the compressed gas discharged from the discharge port 11 of the scroll compressor 100 is supplied to the first drain tank 501. The compressed gas discharged from the discharge port 11 of the scroll compressor 100 contains water vapor, and the water vapor contained in the compressed gas supplied to the first drain tank 501 is cooled after being supplied to the first drain tank 501 and accumulates at the lower part of the first drain tank 501. That is, the first drain tank 501 is a separator that removes moisture contained in the gas.

[0066] The compressed gas flowing from the first drain tank 501 toward the solenoid valve 502 is supplied to the solenoid valve 502. The solenoid valve 502 can switch between a state of supplying the compressed gas to the upper space formed above the actuator 503 through the pipe 512 and a state of supplying the compressed gas to the lower space formed below the actuator 503 through the pipe 513. A piston (not shown) is disposed between the upper space formed above the actuator 503 and the lower space formed below the actuator 503. When the compressed gas is supplied to the upper space formed above the actuator 503, the operating portion 503a connected to the piston moves downward in FIG. 1. When the compressed gas is supplied to the lower space formed below the actuator 503, the operating portion 503a connected to the piston moves upward in FIG. 1.

[0067] The compressed gas flowing out from the solenoid valve 502 passes through the second drain tank 504 and is supplied to the intake chamber 505. The gas supplied to the second drain tank 504 contains water vapor, but the water vapor is cooled after being supplied to the second drain tank 504 and accumulates at the lower part of the second drain tank 504. That is, the second drain tank 504 is a separator that removes moisture contained in the gas. Therefore, only the gas is supplied from the second drain tank 504 to the intake chamber 505. The intake chamber 505 stores the water flowing back from the suction port 14 of the scroll compressor 100 when the drive of the scroll compressor 100 is stopped. In FIG. 1, the water accumulated at the lower part of the intake chamber 505 is the water that flowed back when the drive of the scroll compressor 100 was stopped.

[0068] Also, a part of the compressed gas flowing out from the first drain tank 501 is supplied to the back pressure introduction port 22 of the scroll compressor 100 through the pipe 517. Then, the compressed gas is supplied to the compression chamber 23 (see FIG. 8) of the scroll compressor 100 and is used as a back pressure for pressing the floating scroll 2 toward the fixed scroll 1.

[0069] In the compressed gas supply system 500 of the present embodiment, two pressure control valves 506a and 506b are attached to control the amount of gas flowing from the first drain tank 501 toward the back pressure introduction port 22 of the scroll compressor 100. Specifically, the pressure control valve 506a to which the compressed gas flowing out from the first drain tank 501 is supplied is a normally open type pressure control valve, and the pressure of the flowing out gas can be set to 0.21 MPa. The pressure control valve 506b arranged on the downstream side of the control valve 506a is a normally open type pressure control valve, and the pressure of the flowing out gas can be set to 0.09 MPa. In this way, by the two pressure control valves 506a and 506b, it is possible to control the pressure of the gas flowing toward the back pressure introduction port 22 of the scroll compressor 100 to be 0.1 MPa, and the vertical fluctuation range of the gas supplied to the back pressure introduction port 22 can be reduced.

[0070] Furthermore, drain water accumulated at the lower part of the first drain tank 501 flows out from the pipe 518 connected to the lower part of the first drain tank 501, and the drain water is supplied to the water supply port 103 of the scroll compressor 100. The drain water supplied to the water supply port 103 is supplied into the compression chamber 8 formed between the fixed scroll 1 and the floating scroll 2 of the scroll compressor 100 via the horizontal part 102 of the water supply passage and the vertical part 101 of the water supply passage.

[0071] The pressure in the internal space of the first drain tank 501 is substantially the same as the pressure of the compressed gas discharged from the discharge port 11 of the scroll compressor 100, and the pressure at one end of the pipe 518 is a very high pressure. In contrast, the pressure at the water supply port 103 of the scroll compressor 100 is the intermediate pressure during the compression process, and the pressure at the other end of the pipe 518 is lower than the pressure at one end of the pipe 518. Therefore, due to the pressure difference between the internal space of the first drain tank 501 and the water supply port 103 of the scroll compressor 100, the drain water accumulated at the bottom of the first drain tank 501 flows out toward the water supply port 103. Note that after starting the drive of the scroll compressor 100, until the pressure at the water supply port 103 of the scroll compressor 100 rises to the intermediate pressure, there is a possibility that water may flow backward from the water supply port 103 of the scroll compressor 100 into the internal space of the first drain tank 501. Therefore, a check valve 103 is attached to the pipe 518.

[0072] When the pressure difference between the internal space of the first drain tank 501 and the water supply port 103 of the scroll compressor 100 is the same, the larger the horizontal cross-sectional area of the internal space of the first drain tank 501, the larger the amount of drain water flowing out from the first drain tank 501 compared to the case where the horizontal cross-sectional area is small. The size of the horizontal cross-sectional area of the internal space of the first drain tank 501 is preferably set so that an appropriate amount of water is supplied from the vertical portion 101 of the water supply passage to the compression chamber 8. In the scroll compressor 100 of the present embodiment, for example, with the horizontal cross-sectional area of the internal space of the first drain tank 501 being a predetermined size and the pressure difference between the internal space of the first drain tank 501 and the water supply port 103 of the scroll compressor 100 being a predetermined pressure, the size of the opening of the vertical portion 101 of the water supply passage may be changed to various sizes so that an appropriate amount of water is supplied from the vertical portion 101 of the water supply passage to the compression chamber 8.

[0073] Thus, when drain water is supplied into the compression chamber 8, compared with the case where drain water is not supplied into the compression chamber 8, the liquid supplied into the compression chamber 8 is compressed to a smaller volume by the volume of the drain water. That is, the compression ratio of the scroll compressor 100 increases. At that time, the drain water supplied into the compression chamber 8 is pushed out between the tip of the first spiral blade 5 of the fixed scroll 1 and the upper surface of the movable substrate 6 of the floating scroll 2, and between the tip of the second spiral blade 7 of the floating scroll 2 and the lower surface of the fixed substrate 4 of the fixed scroll 1. Therefore, the pushed-out water becomes film-shaped and seals between the tip of the first spiral blade 5 of the fixed scroll 1 and the upper surface of the movable substrate 6 of the floating scroll 2, and between the tip of the second spiral blade 7 of the floating scroll 2 and the lower surface of the fixed substrate 4 of the fixed scroll 1. Therefore, in the scroll compressor 100 of the present embodiment, the back pressure can be reduced.

[0074] In the scroll compressor 100 of the present embodiment, the items described in Table 1 were compared between the case where water was supplied into the compression chamber 8 and the case where water was not supplied into the compression chamber 8. For the case where water was supplied into the compression chamber 8, the flow rate of the water supplied from the water supply port 103 to the compression chamber 8 was set to about 5% to about 10% of the discharge flow rate of the scroll compressor 100.

[0075]

Table 1

[0076] In the scroll compressor 100 of the present embodiment, when water is supplied into the compression chamber 8 and the spaces between the tip of the first spiral blade 5 of the fixed scroll 1 and the upper surface of the movable substrate 6 of the floating scroll 2 and between the tip of the second spiral blade 7 of the floating scroll 2 and the lower surface of the fixed substrate 4 of the fixed scroll 1 are sealed by film-shaped water, the maximum discharge pressure increases from 0.35 MPa (comparative example) when water is not supplied into the compression chamber 8 to 0.8 MPa, and the discharge flow rate increases from 3 L / min (comparative example) when water is not supplied into the compression chamber 8 to 5 L / min.

[0077] In order to reduce the back pressure of the scroll compressor 100, the flow rate of water supplied from the water supply port 103 to the compression chamber 8 is preferably about 5% to about 50% of the discharge flow rate of the scroll compressor 100, and more preferably about 25% to about 50%. For example, when the motor rotation speed of the scroll compressor 100 increases, the discharge flow rate increases, and accordingly, the flow rate of water supplied from the water supply port 103 to the compression chamber 8 also increases.

[0078] In addition, in order to reduce the back pressure of the scroll compressor 100, the flow rate of water supplied from the water supply port 103 to the compression chamber 8 is preferably about 5% to about 20% of the volume of the spiral compression chamber 8 of the scroll compressor 100, and more preferably about 5% to about 10%. For example, when the flow rate of water supplied from the water supply port 103 to the compression chamber 8 is about 10% of the volume of the spiral compression chamber 8 of the scroll compressor 100, it means that the flow rate of water is (about 10% of the volume of the compression chamber 8) / min.

[0079] Also, for example, when the flow rate of water supplied from the water supply port 103 to the compression chamber 8 is set to be about 50% or more of the discharge flow rate of the scroll compressor 100, the water supplied to the compression chamber 8 overflows from the spiral compression chamber 8, moves the movable substrate 6 of the floating scroll 2 upward, and flows out radially outward through the gap between the lower surface of the cylindrical outer peripheral wall 5a surrounding the first spiral blade 5 of the fixed scroll 1 and the upper surface of the movable substrate 6 of the floating scroll 2. At this time, a film-like water intervenes between the lower surface of the cylindrical outer peripheral wall 5a surrounding the first spiral blade 5 of the fixed scroll 1 and the upper surface of the movable substrate 6 of the floating scroll 2, so that the load is reduced and the motor torque is decreased.

[0080] In order to reduce the motor torque of the scroll compressor 100, the flow rate of water supplied from the water supply port 103 to the compression chamber 8 is preferably about 50% to about 100% of the discharge flow rate of the scroll compressor 100.

[0081] In addition, the water supplied to the compression chamber 8 flows through the gap between the lower surface of the cylindrical outer peripheral wall 5a surrounding the first spiral blade 5 of the fixed scroll 1 and the upper surface of the movable substrate 6 of the floating scroll 2, thereby having the effect of reducing the temperature of the sliding surface.

[0082] As described above, the scroll compressor 100 of the present embodiment includes a fixed scroll 1 having a configuration in which a first spiral blade 5 is provided on the lower surface of a fixed substrate 4, a floating scroll 2 having a configuration in which a second spiral blade 7 is provided on the upper surface of a movable substrate 6, an eccentric drive mechanism 104 for revolving the floating scroll 2, and a support frame 3 that houses the floating scroll 2 in a revolvable state. The first and second spiral blades 5 and 7 are meshed with each other to form a compression chamber 8, and water is supplied to a location in the compression process in the compression chamber 8 where the volume of the compression chamber 8 decreases as the floating scroll 2 revolves, thereby compressing the gas.

[0083] With this configuration, since water is supplied to a location in the compression process in the compression chamber 8 formed by meshing the first and second spiral blades 5 and 7 with each other, between the tip of the first spiral blade 5 of the fixed scroll 1 and the upper surface of the movable substrate 6 of the floating scroll 2, and between the tip of the second spiral blade 7 of the floating scroll 2 and the lower surface of the fixed substrate 4 of the fixed scroll 1, are sealed by a film of water. As a result, the back pressure for buffering the thrust load due to compression to high pressure is reduced, so that torque loss and compression ratio loss can be reduced.

[0084] In this case, water is supplied to a location in the compression process that is radially inside the suction passage vertical portion 12, which is an opening through which gas is inhaled into the spiral-shaped closed space formed between the first spiral blade 5 and the second spiral blade 7.

[0085] With this configuration, even when the drive of the scroll compressor 100 is stopped, it is possible to suppress the water supplied into the compression chamber 8 from flowing out to the outside.

[0086] In this case, the amount of water supplied from the vertical portion 101 of the water supply passage to the compression chamber 8 (the flow rate of water supplied to a location in the compression process) is set according to the discharge flow rate of the gas discharged from the compression chamber 8.

[0087] With this configuration, the amount of water supplied from the vertical portion 101 of the water supply passage to the compression chamber 8 (the flow rate of water supplied to a location in the compression process) can be appropriately set.

[0088] In this case, the amount of water supplied from the vertical portion 101 of the water supply passage to the compression chamber 8 (the flow rate of water supplied to a location in the compression process) is set according to the volume of the compression chamber 8.

[0089] With this configuration, the amount of water supplied from the vertical portion 101 of the water supply passage to the compression chamber 8 (the flow rate of water supplied to a location in the compression process) can be appropriately set.

[0090] The compressed gas supply system 500 of the present embodiment is characterized by including the scroll compressor 100 described above and a water supply mechanism T that supplies water to a location in the compression process.

[0091] With this configuration, a compressed gas supply system capable of reducing losses in torque cross and compression ratio can be provided.

[0092] In this case, it has a first drain tank 501 which is a tank to which the compressed gas discharged from the scroll compressor 100 is supplied, and the water supply mechanism T supplies the drain water generated in the first drain tank 501 to a location in the compression process.

[0093] With such a configuration, the compressed gas discharged from the scroll compressor 100 contains water vapor. When the compressed gas is cooled after being supplied into the first drain tank 501 which is a tank, drain water is generated. Therefore, without separately securing water supplied to a location in the compression process in the scroll compressor 100, the drain water generated from the water vapor contained in the compressed gas discharged from the scroll compressor 100 can be used. Also, in a compressed gas supply system having a tank to which the compressed gas discharged from the scroll compressor is supplied, the treatment of the drain water generated in the tank becomes a problem. However, by using the drain water as the water supplied to a location in the compression process in the scroll compressor, there is no need to treat the drain water generated in the compressed gas supply system.

[0094] In this case, the water supply mechanism T supplies the drain water to a location in the compression process based on the differential pressure between the gas pressure in the first drain tank 501 and the gas pressure at the location (a location in the compression process) where the water is supplied from the vertical portion 101 of the water supply passage to the compression chamber 8.

[0095] With such a configuration, the drain water in the first drain tank 501 can be easily supplied to a location in the compression process.

[0096] In this case, a check valve 533 that allows the flow of water only in the direction from the first drain tank 501 toward the water supply port 103 is attached to the pipe 518 that supplies the drain water generated in the first drain tank 501 to the water supply port 103 (a location in the compression process) of the scroll compressor 100.

[0097] With such a configuration, when the pressure at the location (a location in the compression process where water is supplied) where the water is supplied from the vertical portion 101 of the water supply passage to the compression chamber 8 is low at the start of compression, it is possible to prevent the drain water from flowing backward from the location in the compression process to the first drain tank 501.

[0098] The above describes an embodiment of the present invention. However, the specific configuration of each part is not limited to the above-described embodiment only, and various modifications are possible without departing from the spirit of the present invention.

[0099] For example, in the above embodiment, the compressed gas supply system 500 has a first drain tank 501 to which the compressed gas discharged from the scroll compressor 100 is supplied, and the water supply mechanism T supplies the drain water generated in the first drain tank 501 to a location in the compression process, but it is not limited thereto. For example, the compressed gas supply system 500 may have a tank containing water for supplying to a location in the compression process, and the water supply mechanism T may supply the water contained in the tank to a location in the compression process.

[0100] In the above embodiment, the water supply mechanism T supplies water to a location in the compression process radially inside the suction passage vertical portion 12, which is an opening through which gas is inhaled into the spiral-shaped closed space formed between the first spiral blade 5 and the second spiral blade 7 of the scroll compressor 100, but it is not limited thereto. The present invention obtains the same effect when water is supplied to a location in the compression process in the compression chamber. That is, the location where water is supplied is arbitrary within the range where water is supplied to a location in the compression process.

[0101] In the above embodiment, a part of the compressed gas discharged from the discharge port 11 is supplied to the pressure chamber 23, and a biasing force acting on the floating scroll 2 toward the fixed scroll 1 acts, but it is not limited thereto. The present invention is also applicable to a scroll compressor in which a biasing force acting on the floating scroll 2 toward the fixed scroll 1 acts by a part of the gas in the compression process in the compression chamber 8. Further, the present invention is also applicable to a scroll compressor in which no biasing force acting on the floating scroll 2 toward the fixed scroll 1 acts.

[0102] In the above embodiment, the case where the compressed gas supply system 500 supplies compressed gas to the actuator 503 has been described. However, the compressed gas supply system 500 that supplies compressed gas is not limited thereto. The present invention is applicable to a compressed gas supply system 500 that supplies compressed gas to any device such as an air chuck or a cylinder, for example.

Explanation of Reference Numerals

[0103] 1…Fixed scroll 2…Floating scroll 3…Support frame 4…Fixed substrate 5…First scroll blade 6…Movable substrate 7…Second scroll blade 8…Compression chamber 12…Vertical portion (opening) of intake passage 104…Eccentric drive mechanism 100…Scroll compressor 500…Compressed gas supply system 501…First drain tank (tank) T…Water supply mechanism

Claims

1. A fixed scroll having a configuration in which first scroll blades are provided on the lower surface of a fixed substrate, A floating scroll having a configuration in which second scroll blades are provided on the upper surface of a movable substrate, An eccentric drive mechanism for revolving the floating scroll, and a support frame for accommodating the floating scroll in a revolvable state, The first and second scroll blades are meshed with each other to form a compression chamber, and water is supplied to a location in the compression chamber where the compression process is occurring, and the compression chamber moves while decreasing in volume due to the revolution of the floating scroll, thereby compressing the gas. A scroll compressor characterized by this.

2. Water is supplied to a location in the compression process that is radially inside the opening through which gas is inhaled into the spiral-shaped closed space formed between the first scroll blade and the second scroll blade. The scroll compressor according to claim 1, characterized by this.

3. The flow rate of water supplied to a location in the compression process is set according to the discharge flow rate of the gas discharged from the compression chamber. The scroll compressor according to claim 1 or 2, characterized by this.

4. The flow rate of water supplied to a location in the compression process is set according to the volume of the compression chamber. The scroll compressor according to claim 1 or 2, characterized by this.

5. A scroll compressor according to any one of claims 1 to 4, A compressed gas supply system characterized by comprising a water supply mechanism for supplying water to a location in the compression process.

6. Having a tank to which the compressed gas discharged from the scroll compressor is supplied, The water supply mechanism supplies the drain water generated in the tank to a location in the compression process. The compressed gas supply system according to claim 5, characterized by this.

7. The water supply mechanism supplies the drain water to a location in the compression process by the differential pressure between the gas pressure in the tank and the gas pressure at a location in the compression process. The compressed gas supply system according to claim 6, characterized by this.

8. A check valve that allows the flow of water only in the direction from the tank toward the location in the compression process is attached to the pipe for supplying the drain water generated in the tank to a location in the compression process. The compressed gas supply system according to claim 7, characterized by this.

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