Scroll compressor and air conditioner

Abstract

The invention provides a scroll compressor and the like with high performance and reliability. A scroll compressor (100) is provided with a compression mechanism part (2) which compresses a refrigerant sucked in through a suction chamber (J1) in a compression chamber (C1) and discharges the compressed refrigerant through a discharge port (J2), and the compression mechanism part (2) has a fixed scroll (21) including a scroll-shaped fixed wrap (21b) and an orbiting scroll (22) including a scroll-shaped orbiting wrap (22b). A compression chamber (C1) is formed between the fixed rolling plate (21b) and the rotating rolling plate (22b), the compression mechanism part (2) is provided with a liquid injection hole (H1) for guiding a liquid refrigerant to the compression chamber (C1) and a gas injection hole (H2) for guiding a gas refrigerant to the compression chamber (C2), and the liquid injection hole (H1) is arranged at a position closer to the suction chamber (J1) than the gas injection hole (H2).

Description

Technical Field

[0001] The invention relates to a scroll compressor and an air conditioner. Background Art

[0002] As a technology for supplying liquid refrigerant and gas refrigerant to the compression chamber of a scroll compressor, for example, there is known a technology described in Patent Document 1. That is, Patent Document 1 describes a scroll compressor in which a gas injection hole is provided between a suction hole and a discharge hole and on a side close to the suction hole, and a liquid injection hole is provided between the gas injection hole and the discharge hole.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent No. 2618501 Summary of the invention

[0006] Problems to be solved by the invention

[0007] In the field of refrigeration and air conditioning, there is a need to switch from HFC refrigerants with relatively high global warming potential (GWP: Global Warming Potential) to HFO refrigerants with low global warming potential. However, HFO refrigerants, which are expected to be new refrigerants, tend to have a narrower operating range or lower air conditioning capacity. In addition, it is pointed out that there are refrigerants in HFO refrigerants that are prone to self-decomposition reactions called disproportionation reactions. In the technology described in Patent Document 1, performance is improved by performing gas injection and liquid injection, but if the use of HFO refrigerants and the like is taken into consideration, there is room for improvement in reliability.

[0008] Therefore, an object of the present invention is to provide a scroll compressor and the like having high performance and reliability.

[0009] Solutions to Solve Problems

[0010] In order to solve the above-mentioned problems, a scroll compressor according to the present invention is provided with a compression mechanism part, which compresses the refrigerant sucked in through the suction chamber in the compression chamber, and discharges the compressed refrigerant through the discharge port, the compression mechanism part having: a fixed scroll plate, which includes a spiral fixed wrap; and a revolving scroll plate, which includes a spiral revolving wrap, the compression chamber is formed between the fixed wrap and the revolving wrap, the compression mechanism part has a liquid injection hole for guiding liquid refrigerant or gas-liquid two-phase refrigerant into the compression chamber, and has a gas injection hole for guiding gas refrigerant into the compression chamber, the liquid injection hole is arranged at a position closer to the suction chamber than the gas injection hole.

[0011] Effects of the Invention

[0012] According to the present invention, a scroll compressor and the like having high performance and reliability can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural diagram of an air conditioner including a scroll compressor according to the first embodiment.

[0014] Figure 2 It is a longitudinal sectional view of the scroll compressor according to the first embodiment.

[0015] Figure 3 It is a bottom view of the fixed scroll included in the scroll compressor according to the first embodiment.

[0016] Figure 4 The scroll compressor according to the first embodiment is descriptive diagram in each state where the rotation angle is 0°, 90°, 180°, and 270°.

[0017] Figure 5 It is an explanatory diagram showing the relationship between the rotation angle of the scroll compressor and the pressure of the compression chamber when liquid injection is performed in the scroll compressor according to the first embodiment.

[0018] Figure 6 It is an explanatory diagram showing the relationship between the rotation angle of the scroll compressor and the pressure of the compression chamber when gas injection is performed in the scroll compressor according to the first embodiment.

[0019] Figure 7 It is a Mollier diagram when liquid injection is performed in the scroll compressor according to the first embodiment.

[0020] Figure 8 This is a Mollier diagram when gas injection is performed in the scroll compressor according to the first embodiment.

[0021] Fig. 9 It is a bottom view of a fixed scroll included in a scroll compressor according to a second embodiment.

[0022] Fig.10 The following are explanatory diagrams of the scroll compressor according to the second embodiment in each of the states where the rotation angle is 0°, 90°, 180°, and 270°.

[0023] Fig.11 It is a structural diagram of an air conditioner including a scroll compressor according to a third embodiment. DETAILED DESCRIPTION

[0024] 《First Implementation Mode》

[0025] <Structure of air conditioner>

[0026] Figure 1 1 is a configuration diagram of an air conditioner W1 including the scroll compressor 100 according to the first embodiment.

[0027] in addition, Figure 1 The arrows in the figure indicate the flow of the refrigerant. The air conditioner W1 is a device that performs air conditioning operations such as refrigeration. Figure 1 As shown, the air conditioner W1 includes a scroll compressor 100, an outdoor heat exchanger 71, an outdoor fan 72, a first electromagnetic valve 73, a capillary tube 74, a second electromagnetic valve 75, and expansion valves 76a and 76b. In addition to the above-mentioned structure, the air conditioner W1 also includes a subcooler 77, an indoor heat exchanger 78, an indoor fan 79, an outdoor control circuit 81, and an indoor control circuit 82.

[0028] exist Figure 1 In the example of FIG. 1 , in addition to the scroll compressor 100 and the outdoor heat exchanger 71, the outdoor fan 72, the first electromagnetic valve 73, the capillary tube 74, the second electromagnetic valve 75, the expansion valve 76a, the subcooler 77, and the outdoor control circuit 81 are provided in the outdoor unit U1. In addition, in addition to the expansion valve 76b and the indoor heat exchanger 78, the indoor fan 79 and the indoor control circuit 82 are also provided in the indoor unit U2.

[0029] The scroll compressor 100 is a device that compresses a low-temperature, low-pressure gas refrigerant and discharges it as a high-temperature, high-pressure gas refrigerant. The outdoor heat exchanger 71 is a heat exchanger that performs heat exchange between the refrigerant flowing in the heat transfer pipe (not shown) and the outside air sent in from the outdoor fan 72. In the first embodiment, the air conditioner W1 is configured such that the outdoor heat exchanger 71 functions as a condenser, and on the other hand, the indoor heat exchanger 78 functions as an evaporator. The outdoor fan 72 is a fan that sends outside air to the outdoor heat exchanger 71, and is arranged near the outdoor heat exchanger 71.

[0030] The first solenoid valve 73 is a valve for injecting liquid through the liquid injection hole H1 (see Figure 2 The first electromagnetic valve 73 is switched on and off based on the instruction from the outdoor control circuit 81. The capillary tube 74 decompresses the refrigerant flowing through the first electromagnetic valve 73. Figure 1 As shown, the outdoor heat exchanger 71, the first electromagnetic valve 73 and the capillary tube 74 are sequentially connected via pipes. The refrigerant decompressed by the capillary tube 74 is sequentially passed through the liquid injection pipe P3 and the liquid injection hole H1 (see Figure 2 ) is supplied to the compression chamber C1 (refer to Figure 4 ).

[0031] Figure 1The second solenoid valve 75 shown is for the gas injection hole H2 (see Figure 2 ) is switched to supply or cut off the gas refrigerant. And, based on the instruction from the outdoor control circuit 81, the switch of the second solenoid valve 75 is switched.

[0032] The expansion valve 76a decompresses the refrigerant flowing through the second solenoid valve 75. Figure 1 In the example of FIG. 7 , the outdoor heat exchanger 71 , the second electromagnetic valve 75 , the expansion valve 76 a , and the secondary flow pipe 77 b of the subcooler 77 are sequentially connected via pipes.

[0033] The subcooler 77 is a heat exchanger that performs heat exchange between the refrigerant flowing through the main flow pipe 77a and the refrigerant flowing through the secondary flow pipe 77b. As a result, the refrigerant flowing through the main flow pipe 77a is cooled, and the cooled refrigerant is further decompressed by the expansion valve 76b, thereby improving the air conditioning capacity of the air conditioner W1. On the other hand, the refrigerant evaporated in the secondary flow pipe 77b of the subcooler 77 is sequentially discharged through the gas injection pipe P4 and the gas injection hole H2 (see Figure 2 ) and supplied to the compression chamber. In addition, on the downstream side of the outdoor heat exchanger 71, there are three pipes branched into a pipe K1 that guides the refrigerant to the first solenoid valve 73, a pipe K2 that guides the refrigerant to the second solenoid valve 75, and a pipe K3 that guides the refrigerant to the main pipe 77a of the subcooler 77.

[0034] The expansion valve 76b decompresses the refrigerant cooled by the main flow pipe 77a of the subcooler 77. The indoor heat exchanger 78 is a heat exchanger (evaporator) that performs heat exchange between the refrigerant flowing through the heat transfer pipe (not shown) and the indoor air sent in from the indoor fan 79. Figure 1 In the example of , the main flow pipe 77a of the subcooler 77, the expansion valve 76b, and the indoor heat exchanger 78 are connected in sequence via pipes. The refrigerant evaporated in the indoor heat exchanger 78 is guided to the suction side of the scroll compressor 100 via the suction pipe P1. In addition, a liquid accumulator (not shown) for gas-liquid separation of the refrigerant may also be connected to the suction side of the scroll compressor 100.

[0035] The indoor fan 79 is a fan that sends indoor air to the indoor heat exchanger 78 and is provided near the indoor heat exchanger 78. The air sucked into the indoor unit U2 is cooled by heat exchange with the refrigerant in the indoor heat exchanger 78, and the cooled refrigerant is blown out to the air-conditioned room.

[0036] The outdoor control circuit 81 controls the expansion valve 76a, the outdoor fan 72, the scroll compressor 100, etc. in a predetermined manner in addition to the first solenoid valve 73 and the second solenoid valve 75 based on a predetermined program. The indoor control circuit 82 controls the expansion valve 76b and the indoor fan 79 in a predetermined manner. In addition, the outdoor control circuit 81 and the indoor control circuit 82 exchange data with each other via a communication line. Although not shown in the figure, the outdoor control circuit 81 and the indoor control circuit 82 are respectively constructed to include electronic circuits such as a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and various interfaces. Then, the program stored in the ROM is read out and expanded in the RAM, and the CPU performs various processes. Hereinafter, the outdoor control circuit 81 and the indoor control circuit 82 are collectively referred to as the "control unit 80".

[0037] <Structure of scroll compressor>

[0038] Figure 2 It is a longitudinal sectional view of the scroll compressor 100 .

[0039] Figure 2 The scroll compressor 100 shown is a device for compressing a gaseous refrigerant. In addition, the refrigerant used by the scroll compressor 100 may be an HFO refrigerant, or may be a predetermined refrigerant other than the HFO refrigerant. As HFO refrigerants (the refrigerant numbers are in parentheses below), for example, monofluoroethylene (R1141), trans-1,2-difluoroethylene (R1132(E)), cis-1,2-difluoroethylene (R1132(Z)), 1,1-difluoroethylene (R1132a), trifluoroethylene (R1123) or tetrafluoroethylene (R1114) are sometimes used.

[0040] like Figure 2 As shown, the scroll compressor 100 includes a closed container 1, a compression mechanism 2, a crankshaft 3, a main bearing 4, a swivel bearing 5, a motor 6, and an Oldham ring 7. In addition to the above-mentioned structure, the scroll compressor 100 also includes balance weights 8, 9, a subframe 10, a subbearing 11, an oil supply pump 12, and a leg 13.

[0041] The sealed container 1 is a container that accommodates the compression mechanism 2, the crankshaft 3, the motor 6, etc., and is generally sealed. The sealed container 1 includes a cylindrical barrel chamber 1a, a cover chamber 1b that blocks the upper opening of the barrel chamber 1a, and a bottom chamber 1c that blocks the lower opening of the barrel chamber 1a. A suction pipe P1 is inserted and fixed in the cover chamber 1b of the sealed container 1. The suction pipe P1 is a pipe that connects the indoor heat exchanger 78 (evaporator: see Figure 1 ) is a pipe that guides the evaporated refrigerant into the suction chamber J1 of the compression mechanism part 2.

[0042] A discharge pipe P2 is inserted and fixed in the cylinder chamber 1a of the closed container 1. The discharge pipe P2 is a pipe that guides the refrigerant compressed by the compression mechanism 2 to the outside of the scroll compressor 100. In addition, the refrigerant flowing through the discharge pipe P2 is guided to the outdoor heat exchanger 71 (condenser: see Figure 1 Lubricating oil for improving lubricity in the scroll compressor 100 is enclosed in the sealed container 1 and stored at the bottom of the sealed container 1 as an oil reservoir R1.

[0043] The compression mechanism 2 compresses the refrigerant sucked through the suction chamber J1 in the compression chamber C1 and discharges the compressed refrigerant through the discharge port J2. The compression mechanism 2 includes a fixed scroll 21, an orbiting scroll 22, and a frame 23, and is disposed in the upper space of the closed container 1.

[0044] The fixed scroll 21 is a component that forms the compression chamber C1 together with the orbiting scroll 22. The fixed scroll 21 is disposed on the upper side of the frame 23 and is fixed to the frame 23 by bolts (not shown). Figure 2 As shown, the fixed scroll 21 includes a base plate 21 a and a fixed wrap 21 b .

[0045] The base plate 21a is a thick member that is circular in plan view. The base plate 21a is provided with a suction chamber J1 that guides the refrigerant through the suction pipe P1. The fixed wrap 21b is in a spiral shape (see also Figure 3 ), extending downward from the base plate 21a. The lower surface of the portion of the base plate 21a that is closer to the outside than the fixed wrap 21b is substantially flush with the tooth top of the fixed wrap 21b.

[0046] like Figure 2 As shown, a liquid injection hole H1 and a gas injection hole H2 are provided on the platen 21a. That is, the compression mechanism 2 has a liquid injection hole H1 and a gas injection hole H2. The liquid injection hole H1 is a hole for guiding liquid refrigerant (or gas-liquid two-phase refrigerant) to the compression chamber C1. The gas injection hole H2 is a hole for guiding gas refrigerant to the compression chamber.

[0047] like Figure 2 As shown, a liquid injection pipe P3 is inserted into the cover chamber 1b of the closed container 1, and a gas injection pipe P4 is inserted and fixed. The liquid injection pipe P3 is a pipe that guides liquid refrigerant (or gas-liquid two-phase refrigerant) to the liquid injection hole H1. As described above, the outdoor heat exchanger 71 (condenser: see Figure 1 ) The condensed liquid refrigerant passes through the first solenoid valve 73 (refer to Figure 1 ) and capillary 74 (refer to Figure 1 ) is guided to the liquid injection pipe P3.

[0048] Figure 2 The gas injection pipe P4 shown is a pipe for guiding the gas refrigerant to the gas injection hole H2. Figure 1 ) flows out and is expanded by the expansion valve 76a (refer to Figure 1 ) is decompressed, and then in the subcooler 77 (refer to Figure 1 The gas refrigerant evaporated in the secondary flow pipe 77b of the gas injection pipe is guided to the gas injection pipe P4.

[0049] Figure 2 The orbiting scroll 22 shown is a member that forms a compression chamber C1 between the fixed scroll 21 and the orbiting scroll 22 by its orbiting (movement). The orbiting scroll 22 includes a circular plate-shaped mirror plate 22a, a spiral orbiting wrap 22b (also see Figure 4 ), and the boss portion 22c is engaged with the eccentric portion 3b of the crankshaft 3. Figure 2 As shown, the spiral wrap 22b extends upward from the mirror plate 22a. On the other hand, the boss portion 22c extends downward from the mirror plate 22a.

[0050] The spiral fixed wrap 21b of the fixed scroll 21 meshes with the spiral orbiting wrap 22b of the orbiting scroll 22, thereby forming a compression chamber C1 between the fixed wrap 21b and the orbiting wrap 22b. The compression chamber C1 is a space for compressing the gaseous refrigerant, and is formed on the outer line side and the inner line side of the orbiting wrap 22b (see also Figure 4 A discharge port J2 for discharging the refrigerant compressed in the compression chamber C1 to the upper space in the closed container 1 is provided near the center of the base plate 21 a of the fixed scroll 21 .

[0051] The space between the back side of the mirror plate 22a of the orbiting scroll 22 and the frame 23 functions as a back pressure chamber B1. A predetermined back pressure acts in the back pressure chamber B1 to press the orbiting scroll 22 toward the fixed scroll 21.

[0052] Figure 2 The frame 23 shown is a component for supporting the fixed scroll 21 or fixing the main bearing 4, and has a substantially rotationally symmetrical shape. The frame 23 is fixed to the closed container 1 and fixed to the lower side of the fixed scroll 21. The frame 23 is provided with a hole (symbol not shown) for inserting the crankshaft 3.

[0053] The crankshaft 3 is a shaft that rotates integrally with the rotor 62 of the motor 6 and extends in the up-down direction. Figure 2As shown, the crankshaft 3 includes a main shaft portion 3a and an eccentric portion 3b extending upward from the main shaft portion 3a. The main shaft portion 3a is coaxially fixed to the rotor 62 of the motor 6 and rotates integrally with the rotor 62. The eccentric portion 3b is a shaft that rotates while being eccentric relative to the main shaft portion 3a, and as described above, is engaged with the boss portion 22c of the orbiting scroll 22. And, the orbiting scroll 22 is rotated by the eccentric portion 3b rotating while being eccentric.

[0054] Although not shown in the figure, an oil supply passage for lubricating oil to flow is provided inside the crankshaft 3. The lubricating oil flowing through the oil supply passage is guided to the main bearing 4, the orbiting bearing 5, the auxiliary bearing 11, etc. in addition to being guided to the compression mechanism 2. The main bearing 4 rotatably supports the upper part of the main shaft portion 3a on the frame 23 and is provided on the circumferential surface of the hole (symbol not shown) of the frame 23. The orbiting bearing 5 rotatably supports the eccentric portion 3b on the boss portion 22c of the orbiting scroll 22 and is provided on the inner circumferential surface of the boss portion 22c.

[0055] The motor 6 is a driving source for rotating the crankshaft 3, and is disposed inside the sealed container 1. The motor 6 includes a stator 61 and a rotor 62, and is disposed between the frame 23 and the sub-frame 10. The stator 61 is fixed to the inner circumferential surface of the cylinder chamber 1a by press-fitting or the like. The rotor 62 is rotatably arranged radially inside the stator 61. Furthermore, by energizing the winding of the stator 61 in a predetermined manner to generate magnetic attraction and repulsion, the rotor 62 rotates.

[0056] The Oldham ring 7 is a wheel-shaped member that receives the eccentric rotation of the eccentric portion 3 b and causes the orbiting scroll 22 to orbit without rotating on its own. The Oldham ring 7 is provided between the orbiting scroll 22 and the frame 23 .

[0057] The balance weights 8 and 9 are components for suppressing the vibration of the scroll compressor 100. Figure 2 In the example of , the balancing weight 8 is provided between the compression mechanism 2 and the motor 6 and is fixed to the crankshaft 3. And, as the motor 6 is driven, the balancing weight 8 rotates integrally with the crankshaft 3. Another balancing weight 9 is provided on the lower side of the rotor 62 of the motor 6. The balancing weight 9 is semicircular in shape when viewed from above and is provided on the opposite side of the balancing weight 8 on one side in the circumferential direction.

[0058] The subframe 10 axially supports the lower portion of the crankshaft 3 and is fixed to the inner circumferential surface of the sealed container 1. The subbearing 11 is a bearing that axially supports the lower portion of the crankshaft 3 and receives radial load from the crankshaft 3. The subbearing 11 is fixed to the circumferential surface of a hole (symbol not shown) of the subframe 10 by press fitting or the like.

[0059] The oil supply pump 12 is a pump that sucks up lubricating oil from the oil storage portion R1 of the closed container 1 and guides it to the oil supply flow path (not shown) of the crankshaft 3, and is provided at the lower end of the crankshaft 3. As such an oil supply pump 12, for example, a trochoid pump is used. The leg 13 supports the closed container 1 and is provided in the bottom chamber 1c.

[0060] <About Refrigerant Injection>

[0061] HFO refrigerant has the advantage of low global warming potential (GWP), but the temperature of the ejected gas tends to rise, and the compression ratio tends to become higher. As a result, there is a tendency for the operating range of the scroll compressor 100 (the pressure range of the refrigerant that can operate) to become narrower and the air conditioning capacity to become lower. In addition, in HFO refrigerants (especially fluoroethylene refrigerants), a self-decomposition reaction called a disproportionation reaction may also occur. The disproportionation reaction refers to the phenomenon that when a predetermined ignition energy is applied under a high temperature and high pressure environment, a predetermined reaction proceeds in a chain reaction, generating a large amount of reaction heat and a sharp pressure rise.

[0062] Therefore, in the first embodiment, the refrigerant disproportionation reaction is suppressed by liquid injection, the operating range of the scroll compressor 100 is expanded, and high efficiency is achieved by gas injection.

[0063] Figure 3 It is a bottom view of the fixed scroll 21 included in the scroll compressor.

[0064] like Figure 3 As shown, a liquid injection hole H1 and a gas injection hole H2 are provided on the base plate 21a of the fixed scroll 21. As described above, the liquid injection hole H1 is a hole for injecting gas from the outdoor heat exchanger 71 (see Figure 1 ) is a hole for guiding the condensed liquid refrigerant (or gas-liquid two-phase refrigerant) to the compression chamber. In addition, the gas injection hole H2 is a hole for guiding the condensed liquid refrigerant (or gas-liquid two-phase refrigerant) to the compression chamber in the subcooler 77 (refer to Figure 1 ) of the secondary flow pipe 77b (refer to Figure 1 ) is a hole that guides the evaporated gas refrigerant into the compression chamber.

[0065] like Figure 3 As shown, the liquid injection hole H1 is arranged at a position closer to the suction chamber J1 than the gas injection hole H2. In addition, "close to the suction chamber J1" means that in the spiral gap between the fixed wraps 21b (the spiral path from the suction chamber J1 to the discharge port J2), the liquid injection hole H1 is closer to the suction chamber J1 than the gas injection hole H2. In addition, the radial distance between the center of the liquid injection hole H1 and the discharge port J2 is longer than the radial distance between the center of the gas injection hole H2 and the discharge port J2.

[0066] The liquid injection hole H1 and the gas injection hole H2 are respectively provided near the center of the gap between the fixed wraps 21b in the radial direction centered on the discharge port J2. The function and effect of such a positional relationship will be described later. In addition, the diameter of the liquid injection hole H1 is larger than that of the spiral wrap 22b (see Figure 4 ) is smaller in thickness. Similarly, the diameter of the gas injection hole H2 is also smaller than that of the spiral wrap 22b (refer to Figure 4 ) is small. This can prevent the liquid injection hole H1, the gas injection hole H2 and the spiral wrap 22b (see Figure 4 )'s outer and inner compression chambers are connected simultaneously.

[0067] Figure 4 The diagrams are explanatory diagrams of states where the rotation angle of the scroll compressor is 0°, 90°, 180°, and 270°.

[0068] In addition, Figure 4 In addition to the hatching on the spiral wrap 22b, a predetermined compression chamber C1 formed on the inner line side of the spiral wrap 22b among the plurality of compression chambers is indicated by dots. Figure 4 As shown in FIG. 1 , a plurality of compression chambers are formed on the inner and outer sides of the spiral wrap 22b. Figure 4 The predetermined compression chamber C1 shown by the midpoint will be described.

[0069] When the rotation angle of the scroll compressor 100 is 0°, the compression chamber C1 is formed near the suction chamber J1. When the rotation angle is 0°, the orbiting wrap 22b overlaps the liquid injection hole H1, and the liquid injection hole H1 is not yet connected to the compression chamber C1. In addition, the compression chamber C1 is not yet connected to the gas injection hole H2.

[0070] When the scroll compressor 100 rotates at an angle of 90°, the liquid injection hole H1 communicates with the compression chamber C1. Figure 1 ) is opened, the liquid refrigerant condensed by the outdoor heat exchanger 71 is injected into the compression chamber C1 through the liquid injection hole H1. As a result, the temperature of the liquid refrigerant decreases due to the vaporization heat phenomenon when the liquid refrigerant is vaporized into gas in the compression chamber C1. Therefore, as described later, in addition to expanding the operating range of the scroll compressor 100, the disproportionation reaction of the refrigerant can also be suppressed.

[0071] like Figure 4 As shown in the state of the rotation angle of 90°, the liquid injection hole H1 is set at a position that is not connected to the suction chamber J1 and is connected to the compression chamber C1 just after the compression chamber C1 is formed. The details will be described later, but by setting it to such a configuration, as described later, in addition to promoting cooling by utilizing the vaporization heat phenomenon in the compression chamber C1, it is also possible to reduce the pressure pulsation associated with liquid injection.

[0072] like Figure 4 As shown in FIG. 1 , the liquid injection hole H1 and the gas injection hole H2 are provided at positions that are not connected to each other. That is, the liquid injection hole H1 and the gas injection hole H2 are not connected to each other via a predetermined compression chamber. Figure 4 In the example, a liquid injection hole H1 is provided near the suction chamber J1, and a gas injection hole H2 is provided near the discharge port J2. As described below, in addition to expanding the operating range of the scroll compressor 100 and suppressing the disproportionation reaction, high efficiency can be achieved.

[0073] exist Figure 4 In the example, when the rotation angle of the scroll compressor 100 is 180°, the other compression chamber C2 is connected to the gas injection hole H2, but the compression chamber C1 is not yet connected to the gas injection hole H2. When the rotation angle is 270°, the compression chamber C1 is very close to the gas injection hole H2, but the orbiting wrap 22b overlaps the gas injection hole H2.

[0074] When the rotation angle of the scroll compressor 100 becomes 0° again, although not shown, the compression chamber C1 communicates with the gas injection hole H2. Figure 1 ) is opened, by the subcooler 77 (refer to Figure 1 ) The evaporated gas refrigerant is injected into the compression chamber C1 through the gas injection hole H2. The details will be described later. By injecting the gas in the second half of the refrigerant compression process, the refrigerant can be prevented from flowing back into the suction chamber J1, thereby reducing the heating loss. In addition, Figure 4 The states at the various rotation angles shown are merely examples and are not limited thereto.

[0075] In addition, it is not necessary to perform both liquid injection and gas injection at the same time. That is, the control unit 80 (refer to Figure 1 ) performs liquid injection, and when other conditions are met, the control unit 80 performs gas injection. Figure 1 ) respectively independently control the first solenoid valve 73 (refer to Figure 1 ) and the second solenoid valve 75 (refer to Figure 1 ), so that liquid injection and gas injection can be performed independently based on predetermined conditions. In addition, the conditions for performing liquid injection or gas injection will be described later.

[0076] Figure 5 It is an explanatory diagram showing the relationship between the rotation angle of the scroll compressor and the pressure of the compression chamber when liquid injection is performed.

[0077] also, Figure 5The horizontal axis is the scroll compressor 100 (refer to Figure 2 When the rotation angle is 0°, a compression chamber C1 (see Figure 4 The "rotation angle 0°") is the state where the suction is completed. Figure 5 The vertical axis is the compression chamber C1 (refer to Figure 4 ) pressure.

[0078] Figure 5 The dashed line graph shown is a predetermined theoretical adiabatic curve. Figure 5 The single-point dashed line graph is a finger pressure line graph when liquid is ejected using the structure of the comparative example. Figure 3 The position of the gas injection hole H2 shown is a structure in which liquid injection is performed instead of gas injection. Figure 5 The solid line graph is a finger pressure graph when liquid is ejected in the structure of the first embodiment. Figure 5 In the solid line graph, no gas injection is performed in particular.

[0079] As described above, immediately after the compression chamber C1 is formed (see Figure 4 ) After that, the liquid injection hole H1 communicates with the compression chamber C1. Thus, the pressure of the compression chamber C1 immediately before the communication between the liquid injection hole H1 and the compression chamber C1 is equal to the suction pressure P s Therefore, immediately after the liquid injection starts (rotation angle θ1), the pressure P of the liquid refrigerant in the liquid injection hole H1 is L_inj The pressure in the compression chamber C1 (suction pressure P s As a result, the flow rate and flow velocity of the liquid refrigerant toward the compression chamber C1 are sufficiently ensured, and cooling is promoted by the heat of vaporization in the compression chamber C1, thereby suppressing the occurrence of the disproportionation reaction.

[0080] In addition, the liquid injection hole H1 (see Figure 4 ) is disposed near the suction chamber J1 and not in communication with the suction chamber J1. This prevents high-pressure liquid refrigerant from flowing into the suction chamber J1 through the liquid injection hole H1. Therefore, the heating loss during compression of the refrigerant can be reduced, achieving high efficiency.

[0081] In addition, even when using HFO refrigerant, it is possible to suppress an excessive rise in discharge temperature, and therefore, even when using HFO refrigerant whose pressure ratio tends to be high, it is possible to expand the operating range of the scroll compressor 100. As described above, the "operating range" of the scroll compressor 100 refers to the pressure range within which the scroll compressor 100 can be operated at each rotation speed. Figure 5In the comparative example (single-dot chain line), the timing (rotation angle θ3) of starting liquid injection is delayed, so the pressure difference ΔP3 becomes smaller, resulting in that the flow rate and flow velocity of the liquid refrigerant in the liquid injection become smaller.

[0082] exist Figure 5 In the example, liquid injection is performed within the range from the rotation angle θ1 just after the compression chamber C1 is formed to the predetermined rotation angle θ2. In addition, in the first half of the process in which the refrigerant is compressed, the gradient of the pressure rise in the compression chamber C1 is relatively small. Therefore, in the structure of the first embodiment (the solid line graph), the fluctuation range ΔP2 of the pressure of the compression chamber C1 between the start (rotation angle θ1) and the end (rotation angle θ2) of the liquid injection is suppressed. As a result, the pressure pulsation accompanying the liquid injection can be reduced, thereby suppressing the noise and vibration of the scroll compressor 100. In addition, in the comparative example (single-dot chain line), the moment when the liquid injection ends (rotation angle θ4) is delayed, and therefore, the pressure fluctuation range ΔP4 becomes larger, and as a result, the pressure pulsation accompanying the liquid injection becomes larger.

[0083] Figure 6 It is an explanatory diagram showing the relationship between the rotation angle of the scroll compressor and the pressure of the compression chamber when the gas injection is performed.

[0084] also, Figure 6 The horizontal axis is the scroll compressor 100 (refer to Figure 2 )’s rotation angle. Figure 6 The vertical axis is the compression chamber C1 (refer to Figure 4 ) pressure. Figure 6 The dashed line graph shown is a predetermined theoretical adiabatic curve. Figure 6 The single-point dashed line graph is a finger pressure line graph when the gas jet is performed in the structure of the comparative example. Figure 3 The position of the liquid injection hole H1 shown is a structure in which liquid is not injected but gas is injected. Figure 6 The solid line graph is a finger pressure graph when the gas jet is performed in the structure of the first embodiment. Figure 6 In the solid line graph, no particular liquid injection is performed.

[0085] As described above, in the first embodiment, the liquid injection hole H1 (see Figure 3 ) A gas injection hole H2 is provided on the side close to the discharge port J2 (refer to Figure 3 ). Thus, the pressure P of the compression chamber C1 immediately before the communication between the gas injection hole H2 and the compression chamber C1 is started is G_NEW Therefore, immediately after the gas injection starts (rotation angle θ7), the pressure P of the gas refrigerant in the gas injection hole H2 is G_inj The pressure P in the compression chamber C1G_NEW The pressure difference ΔP7 between the compression chamber C1 and the suction chamber J1 becomes smaller. As a result, the backflow of the refrigerant from the compression chamber C1 to the suction chamber J1 is suppressed, so that the heating loss can be reduced and high efficiency can be achieved. In addition, in the comparative example (single-dot chain line), since the start time of the gas injection (rotation angle θ6) is faster, the pressure difference ΔP6 becomes larger, and as a result, the heating loss also becomes larger.

[0086] Figure 7 This is a Mollier diagram when liquid is ejected.

[0087] also, Figure 7 The horizontal axis is the specific enthalpy of the refrigerant, and the vertical axis is the pressure of the refrigerant. Figure 7 The saturated vapor line 91 shown is a boundary line between the gas phase and the gas-liquid two-phase in the state of the refrigerant. Figure 7 The saturated liquid line 92 shown is the boundary line between the liquid phase and the gas-liquid two-phase state of the refrigerant. In the area surrounded by the saturated vapor line 91 and the saturated liquid line 92, the refrigerant is in a gas-liquid two-phase state. In addition, the boundary point between the saturated vapor line 91 and the saturated liquid line 92 is called a critical point 93.

[0088] Figure 7 The dotted line M1 of the trapezoid shown is a Mollier diagram when no liquid or gas injection is performed. Figure 7 The solid line M2 shown is a Mollier diagram when liquid injection is performed in the first embodiment. In addition, in the solid line M2, gas injection is not particularly performed. In the first embodiment, by Figure 4 ) near the surface, the specific enthalpy of the refrigerant decreases (refer to Figure 7 As a result, the disproportionation reaction when using HFO refrigerant can be suppressed.

[0089] Figure 8 This is the Mollier diagram when a gas jet is being injected.

[0090] Figure 8 The dotted line M1 of the trapezoid shown is a Mollier diagram when no liquid injection and gas injection are performed. Figure 8 The solid line M3 shown is a Mollier diagram when gas injection is performed in the first embodiment. In addition, in the solid line M3, liquid injection is not particularly performed. In the first embodiment, by Figure 4 ) near the gas injection, the specific enthalpy of the refrigerant decreases (refer to Figure 8 As a result, the compression efficiency of the refrigerant can be improved, thereby achieving high efficiency.

[0091] Furthermore, when both liquid injection and gas injection are performed simultaneously, although not shown in the figure, the specific enthalpy decreases in two stages during the compression process of the refrigerant. Therefore, in this case as well, the disproportionation reaction can be suppressed and the efficiency can be improved.

[0092] <Liquid Injection Conditions>

[0093] For example, when the pressure ratio in the scroll compressor 100 is above a predetermined value, the control unit 80 can open the first solenoid valve 73. Here, the "pressure ratio" refers to the ratio of the discharge pressure of the scroll compressor 100 to the suction pressure. In this way, when the pressure ratio is above a predetermined value, the control unit 80 opens the first solenoid valve 73, thereby supplying liquid refrigerant to the compression chamber, and the refrigerant in the compression chamber is cooled. As a result, the discharge temperature is suppressed from reaching a predetermined upper limit temperature, so that the operating range of the scroll compressor 100 can be expanded. In addition, the pressure ratio can also be calculated based on the detection values ​​of the suction pressure and the discharge pressure of the scroll compressor 100. In addition, the pressure ratio can also be calculated based on the detection values ​​of the pressure and temperature of other predetermined parts.

[0094] In addition, when the discharge temperature of the scroll compressor 100 is above a predetermined value, the control unit 80 may also open the first solenoid valve 73. As a result, liquid refrigerant is supplied through the liquid injection hole H1, and is therefore cooled in the compression chamber C1 by the heat of vaporization. As a result, the temperature rise of the refrigerant is suppressed, so in addition to being able to expand the operating range of the scroll compressor 100, it is also possible to suppress the disproportionation reaction when using HFO refrigerant. In addition, a temperature sensor (not shown) for detecting the discharge temperature of the scroll compressor 100 is provided, and its detection value is output to the control unit 80 (refer to Figure 1 ). In addition, when liquid is ejected, gas ejection may be performed together, or gas ejection may not be performed in particular.

[0095] <Conditions of gas injection>

[0096] In addition, when the outside air temperature is below a predetermined value, the control unit 80 can open the second solenoid valve 75. The air conditioner W1 is used in cold regions and in a low temperature environment in winter. When the outside air temperature becomes below a predetermined value, the circulation flow rate of the refrigerant becomes smaller, so there is a tendency for the efficiency to decrease. In particular, the density of HFO refrigerant is relatively small, so the circulation flow rate tends to become smaller. Therefore, the control unit 80 opens the second solenoid valve 75 when the outside air temperature is below a predetermined value. As a result, high-pressure gas refrigerant is supplied to the compression chamber, thereby improving the operating efficiency. In addition, an outdoor temperature sensor (not shown) for detecting the outside air temperature is provided on the outdoor unit U1 (refer to Figure 1 ).

[0097] In addition, when the scroll compressor 100 is operated under a predetermined overload condition, the control unit 80 may also open the second solenoid valve 75. In addition, the "overload condition" is pre-set based on the rotation speed, discharge pressure, etc. of the scroll compressor 100. Thus, the scroll compressor 100 can be prevented from stopping under a predetermined protection control, and can continue to operate efficiently. In addition, when performing gas injection, liquid injection may also be performed at the same time, and liquid injection may not be performed in particular.

[0098] <Effect>

[0099] According to the first embodiment, the liquid is ejected through the liquid ejection hole H1 (see Figure 4 ) supplies liquid refrigerant to the compression chamber C1. As a result, the temperature of the liquid refrigerant decreases due to the heat of vaporization when the liquid refrigerant is vaporized into gas in the compression chamber C1, thereby suppressing the disproportionation reaction and expanding the operating range of the scroll compressor 100. In addition, since HFO refrigerant with a low global warming potential (GWP) can be used, it can contribute to suppressing global warming.

[0100] And, by passing through the gas injection hole H2 (refer to Figure 4 ) supplies gas refrigerant, and can efficiently operate the scroll compressor 100. In this way, according to the first embodiment, the performance and reliability of the scroll compressor 100 are improved.

[0101] Second Implementation Method

[0102] The second embodiment is different from the first embodiment in that the fixed scroll 21A (see Fig. 9 ) are provided with two liquid injection holes H11, H12 (refer to Fig. 9 ) and gas injection holes H21, H22 (refer to Fig. 9 ). In addition, the other structures are the same as those of the first embodiment. Therefore, the parts different from the first embodiment will be described, and the description of the repeated parts will be omitted.

[0103] Fig. 9 It is a bottom view of the fixed scroll 21A included in the scroll compressor according to the second embodiment.

[0104] like Fig. 9 As shown in FIG. 1 , two liquid injection holes H11 and H12 are provided in the fixed scroll 21A, and two gas injection holes H21 and H22 are provided. The two liquid injection holes H11 and H12 are arranged along the edge of the fixed wrap 21b in the radial direction with the discharge port J2 as the center. One liquid injection hole H11 is connected to the orbiting wrap 22b (see FIG. 1 ). Fig.10The other liquid injection hole H12 is connected to the spiral wrap 22b (see Fig.10 ) is a hole connected to the compression chamber on the inner line side.

[0105] These liquid injection holes H11, H12 are arranged at positions closer to the suction chamber J1 than the gas injection holes H21, H22. That is, in the spiral gap between the fixed wraps 21b (the spiral path from the suction chamber J1 to the discharge port J2), the liquid injection holes H11, H12 are arranged at positions closer to the suction chamber J1 than the gas injection holes H21, H22.

[0106] Furthermore, the first solenoid valve 73 (see Figure 1 ) is opened, when the liquid injection holes H11 and H12 are connected to the predetermined compression chambers, liquid refrigerant (or gas-liquid two-phase refrigerant) is supplied to each compression chamber through the liquid injection holes H11 and H12. Figure 1 ) is branched into two, and its downstream ends are connected to the liquid injection holes H11 and H12.

[0107] The two gas injection holes H21 and H22 are arranged along the edge of the fixed wrap 21b in the radial direction centered on the discharge port J2. One gas injection hole H21 is connected to the spiral wrap 22b (see Fig.10 The other gas injection hole H22 is connected to the spiral wrap 22b (see Fig.10 ) is a hole connected to the compression chamber on the inner line side.

[0108] Furthermore, in the second solenoid valve 75 (refer to Figure 1 ) is opened, when the gas injection holes H21 and H22 are connected to the predetermined compression chambers, the gas refrigerant is supplied to each compression chamber through the gas injection holes H21 and H22. Figure 1 ) is branched into two, and its downstream end is connected to the gas injection holes H21 and H22.

[0109] Fig.10 The diagrams are explanatory diagrams of states where the rotation angle of the scroll compressor is 0°, 90°, 180°, and 270°.

[0110] For example, if the compression chamber C3 on the inner line side of the spiral wrap 22b is focused, it is connected to the liquid injection hole H12 at a rotation angle of 90°, and is connected to the gas injection hole H22 at a rotation angle of 270°. In addition, if the compression chamber C4 on the outer line side of the spiral wrap 22b is focused, it is connected to the liquid injection hole H11 at a rotation angle of 0° and a rotation angle of 90°, and is connected to the gas injection hole H21 at a rotation angle of 90°, a rotation angle of 180°, and a rotation angle of 270°. In this way, liquid injection and gas injection are respectively performed on the compression chambers formed in sequence.

[0111] In addition, it is not particularly necessary to perform liquid injection and gas injection simultaneously, and liquid injection may be performed when predetermined conditions are satisfied, and gas injection may be performed when other conditions are satisfied. The above-mentioned conditions are the same as those in the first embodiment, and thus description thereof is omitted.

[0112] <Effect>

[0113] According to the second embodiment, in the case of performing either liquid injection or gas injection, the refrigerant is injected to both the outer line side and the inner line side of the orbiting wrap 22b. Thus, liquid injection and gas injection can be performed to the compression chambers formed in sequence. Therefore, in addition to suppressing the disproportionation reaction when using HFO refrigerant, the operating range of the scroll compressor 100 can be expanded and the efficiency can be improved more effectively than in the first embodiment.

[0114] 《Third Implementation Mode》

[0115] The air conditioner W2 of the third embodiment (see Fig.11 ) is different from the first embodiment. In addition, other (structure of the scroll compressor 100, etc.: refer to Figure 2 , Figure 3 ) is the same as the first embodiment. Therefore, the parts different from the first embodiment will be described, and the description of the repeated parts will be omitted.

[0116] Fig.11 It is a structural diagram of an air conditioner including a scroll compressor according to a third embodiment.

[0117] exist Fig.11 In the structure shown, part of the refrigerant condensed in the outdoor heat exchanger 71 is guided to the second electromagnetic valve 75 via the pipe K2, and the remaining refrigerant is guided to the main pipe 77a of the subcooler 77 via the pipe K3. When the second electromagnetic valve 75 is open, the refrigerant flowing out through the second electromagnetic valve 75 is decompressed by the expansion valve 76a, and then evaporates in the secondary flow pipe 77b of the subcooler 77, and is guided to the gas injection hole H2 (see FIG. Figure 2 ).

[0118] In addition, part of the refrigerant cooled by the main flow pipe 77a of the subcooler 77 is guided to the first electromagnetic valve 73 via the pipe K4, and the remaining refrigerant is guided to the indoor heat exchanger 78 via the expansion valve 76b. When the first electromagnetic valve 73 is open, the refrigerant flowing out through the first electromagnetic valve 73 is decompressed by the capillary tube 74 and guided to the liquid injection hole H1 (see FIG. 1 ) via the liquid injection pipe P3. Figure 2 ). In addition, the connection relationship other than the first electromagnetic valve 73 and the capillary tube 74 is the same as that of the first embodiment (see Figure 1 ) are the same, so the description is omitted.

[0119] <Effect>

[0120] According to the third embodiment, the refrigerant cooled by the main flow pipe 77a of the subcooler 77 and decompressed by the capillary tube 74 is guided to the liquid injection hole H1 (see Figure 2 ). Thus, due to the heat of vaporization when the liquid refrigerant is vaporized into gas through the liquid injection hole H1, the compression chamber C1 (refer to Figure 4 ) to promote cooling. Therefore, in addition to being able to expand the operating range of the scroll compressor 100, it is also possible to suppress the disproportionation reaction of the refrigerant.

[0121] 《Variation Example》

[0122] As mentioned above, although the scroll compressor 100 and the air conditioners W1 and W2 according to the present invention have been described in the respective embodiments, the present invention is not limited to these descriptions, and various modifications are possible.

[0123] For example, in the first embodiment, the control unit 80 performs liquid injection when a predetermined condition is satisfied, and performs gas injection when other conditions are satisfied, but the present invention is not limited to this. Figure 1 ) It is also possible to always open the first electromagnetic valve 73 for liquid injection (refer to Figure 1 ) and a second solenoid valve 75 for gas injection (refer to Figure 1 ) or both thereof. The same is true for the second embodiment and the third embodiment.

[0124] In addition, the liquid injection hole H1 (see Figure 3 )、Gas injection hole H2 (refer to Figure 3 ) can be appropriately changed in number and position. In addition, the liquid injection hole H1 is provided at a position closer to the suction chamber J1 than the gas injection hole H2.

[0125] In addition, the various embodiments can be combined as appropriate. For example, the first embodiment and the second embodiment can be combined to provide a liquid injection hole H1 (see Figure 3 ) and two gas injection holes H21, H22 (refer to Fig. 9 ) structure. Alternatively, two liquid injection holes H11 and H12 may be provided (see Fig. 9 ) and a gas injection hole H2 (refer to Figure 3 ) structure.

[0126] Alternatively, the second embodiment and the third embodiment may be combined to use a liquid ejection hole H11 and a liquid ejection hole H12 (see Fig. 9 ) and the scroll compressor 100 having the gas injection holes H21 and H22 constitutes the air conditioner W2 of the structure of the third embodiment (refer to Fig.11 ).

[0127] In each embodiment, the outdoor heat exchanger 71 (see Figure 1 ) is sequentially passed through the first electromagnetic valve 73 and the capillary tube 74 to the liquid injection hole H1 (refer to Figure 2 ) is described above with reference to the embodiment of the present invention, but the present invention is not limited thereto. For example, the capillary tube 74 may be omitted as appropriate, or an expansion valve (not shown) may be provided in place of the capillary tube 74.

[0128] In each embodiment, the outdoor heat exchanger 71 (see Figure 1 ) is sequentially directed to the gas injection hole H2 (refer to Figure 2 ) is described above with reference to the case where the gas refrigerant is guided, but the present invention is not limited thereto. For example, at least one of the expansion valve 76a and the subcooler 77 may be omitted.

[0129] In addition, in each embodiment, the structure in which the scroll compressor 100 is installed vertically is described, but it is not limited to this. For example, each embodiment can also be applied to the structure in which the scroll compressor 100 is installed horizontally or inclined.

[0130] The air conditioner W1 described in each embodiment can be applied to various air conditioners such as a package air conditioner and a multi-split air conditioner for a building in addition to a room air conditioner.

[0131] In the first embodiment, the air conditioner W1 (see Figure 1 ) is described as a case where the structure is dedicated to cooling without a special four-way valve (not shown), but it can also be provided with a four-way valve (not shown) for switching the refrigeration cycle and the heating cycle based on the operation mode. In addition, a flow path switching device (not shown) for switching the flow path of the refrigerant can be separately provided according to the operation mode to guide the liquid refrigerant to the liquid injection hole H1 (refer to Figure 3), and guide the gas refrigerant to the gas injection hole H2 (refer to Figure 3 ). In addition, the air conditioner may be a structure dedicated to heating. In addition, the second embodiment and the third embodiment are also the same.

[0132] In the first embodiment, the air conditioner W1 (see Figure 1 ) is described, but is not limited thereto. For example, the first embodiment can also be applied to other refrigeration cycle devices such as refrigerators, water heaters, air-conditioning water heaters, and cold machines. In addition, the same is true for the second embodiment and the third embodiment.

[0133] In addition, each embodiment is described in detail to explain the present invention in an easy-to-understand manner, and is not necessarily limited to having all the structures described. In addition, for a part of the structure of each embodiment, other structures can be appropriately added, deleted, or replaced.

[0134] In addition, the above-mentioned mechanisms and structures show the structures and structures considered necessary for explanation, and do not necessarily show all the mechanisms and structures in the product.

[0135] Explanation of symbols

[0136] 1—sealed container, 2—compression mechanism, 3—crankshaft, 4—main bearing, 5—orbital bearing, 6—motor, 21, 21A—fixed scroll, 21b—fixed wrap, 22—orbital scroll, 22b—orbital wrap, 23—frame, 71—outdoor heat exchanger, 72—outdoor fan, 73—first solenoid valve, 74—capillary tube, 75—second solenoid valve, 76b—expansion valve, 77—subcooler, 78—indoor heat exchanger, 79—indoor fan, 80—control unit, 100—scroll compressor, C1, C2, C3, C4—compression chamber, H1, H11, H12—liquid injection hole, H2, H21, H22—gas injection hole, J1—intake chamber, J2—discharge port, W1, W2—air conditioner.

Claims

1. A scroll compressor, characterized in that: The device is provided with a compression mechanism portion which compresses the refrigerant sucked in through the suction chamber in the compression chamber and discharges the compressed refrigerant through the discharge port. The compression mechanism has a fixed scroll including a spiral fixed wrap and an orbiting scroll including a spiral orbiting wrap. The compression chamber is formed between the fixed wrap and the revolving wrap. The compression mechanism has a liquid injection hole for introducing a liquid refrigerant or a gas-liquid two-phase refrigerant into the compression chamber, and has a gas injection hole for introducing a gas refrigerant into the compression chamber. The liquid injection hole is provided at a position closer to the suction chamber than the gas injection hole.

2. The scroll compressor according to claim 1, characterized in that: The liquid injection hole and the gas injection hole are provided at positions that are not communicated with each other.

3. The scroll compressor according to claim 1, characterized in that: The liquid injection hole and the gas injection hole are respectively provided near the center of the gap between the fixed wraps in a radial direction centered on the discharge port.

4. The scroll compressor according to claim 1, characterized in that: The liquid injection hole is provided at a position not communicating with the suction chamber and communicating with the compression chamber immediately after the compression chamber is formed.

5. The scroll compressor according to claim 1, characterized in that: The compression mechanism has two liquid injection holes. The two liquid injection holes are arranged side by side in a radial direction centered on the discharge port so as to be along the edge of the fixed wrap.

6. The scroll compressor according to claim 1, characterized in that: The compression mechanism has two gas injection holes. The two gas injection holes are arranged side by side in a radial direction centered on the discharge port so as to be along the edge of the fixed wrap.

7. An air conditioner, characterized in that: A scroll compressor according to any one of claims 1 to 6, an outdoor heat exchanger, an expansion valve, and an indoor heat exchanger, and further comprising: a first solenoid valve that switches supply or cutoff of the liquid refrigerant or the gas-liquid two-phase refrigerant through the liquid injection hole; a second solenoid valve that switches supply or cutoff of the gas refrigerant through the gas injection hole; and A control unit controls the first solenoid valve and the second solenoid valve independently.

8. The air conditioner according to claim 7, characterized in that: The control unit opens the first electromagnetic valve when a pressure ratio in the scroll compressor is equal to or higher than a predetermined value or when a discharge temperature of the scroll compressor is equal to or higher than a predetermined value.

9. The air conditioner according to claim 7, characterized in that: The control unit opens the second electromagnetic valve when the outside air temperature is lower than or equal to a predetermined value or when the scroll compressor is operating under a predetermined overload condition.

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