WO2018096824A1

WO2018096824A1 - Scroll compressor

Info

Publication number: WO2018096824A1
Application number: PCT/JP2017/036937
Authority: WO
Inventors: 啓晶中井; 淳作田
Original assignee: パナソニックＩｐマネジメント株式会社
Priority date: 2016-11-24
Filing date: 2017-10-12
Publication date: 2018-05-31
Also published as: JP6928792B2; EP3546753A4; EP3546753B1; CN109996961B; EP3546753A1; JPWO2018096824A1; US20190309750A1; CN109996961A

Abstract

Provided is a scroll compressor, wherein at least one injection port is provided, passing through a mirror plate of a fixed scroll (12), at a position open to a first compression chamber (15a) or a second compression chamber (15b), which is in a compression stroke performed after sealing a suctioned refrigerant. In addition, among the first compression chamber (15a) and the second compression chamber (15b), the first compression chamber (15a), which is a compression chamber on one side and has a greater amount of refrigerant injected from an injection port (43) than the second compression chamber (15b), is provided with a discharge bypass port (21) such that the volume ratio of the suctioned volume to discharged volume of the second compression chamber (15b) is reduced to allow the refrigerant in the first compression chamber (15a) to be discharged to the second compression chamber (15b), which is the compression chamber on the other side.

Description

Scroll compressor

The present invention relates to a scroll compressor used in refrigerators such as an air conditioner, a water heater, and a refrigerator.

For refrigeration equipment and air conditioning equipment, compression is performed by sucking the gas refrigerant evaporated in the evaporator, compressing the gas refrigerant to the pressure required for condensation in the condenser, and sending the high-temperature and high-pressure gas refrigerant into the refrigerant circuit The machine is being used. The scroll compressor is provided with two expansion valves between the condenser and the evaporator, and the intermediate pressure refrigerant flowing between the two expansion valves is injected into the compression chamber during the compression process, thereby providing a refrigeration cycle. To reduce power consumption and improve capacity.

That is, the refrigerant circulating through the condenser increases by the amount of injected refrigerant, and if it is an air conditioner, the heating capacity is improved. In addition, since the refrigerant to be injected is in an intermediate pressure state and the power necessary for compression is from the intermediate pressure to the high pressure, COP (Coefficient Of Performance) is achieved compared to the case where the same capability is realized without performing injection. ) And power consumption can be reduced.

The amount of refrigerant flowing through the condenser is equal to the sum of the amount of refrigerant flowing through the evaporator and the amount of refrigerant injected, and the ratio of the amount of injected refrigerant to the amount of refrigerant in the condenser is the injection rate.

To increase the effect of injection, the injection rate should be increased. And since a refrigerant | coolant is injected by the pressure difference of the refrigerant | coolant pressure injected and the internal pressure of a compression chamber, in order to make an injection rate high, it is necessary to raise the refrigerant | coolant pressure injected.

However, if the refrigerant pressure to be injected is increased, the liquid refrigerant is injected into the compression chamber, leading to a reduction in heating capacity and a reduction in the reliability of the compressor.

The refrigerant flowing into the compression chamber from the injection pipe is preferentially taken out and sent from the gas-liquid separator. However, when the balance of the intermediate pressure control is lost or transient conditions change, the gas refrigerant It flows from the injection tube in a state where liquid refrigerant is mixed. In order to maintain a good sliding state, an appropriate amount of oil is fed into the compression chamber having many sliding parts and compressed together with the refrigerant. When liquid refrigerant is mixed, the oil in the compression chamber is washed away by the liquid refrigerant. As a result, the sliding state deteriorates, and component wear and seizure occur. Therefore, it is important that the liquid refrigerant flowing from the injection pipe is not sent into the compression chamber as much as possible, and only the gas refrigerant is guided to the injection port.

By adjusting the opening degree of the expansion valve provided on the upstream side and downstream side of the gas-liquid separator, the intermediate pressure is controlled, and the internal pressure and the intermediate pressure of the compression chamber in the compressor to which the injection pipe is finally connected are controlled. The injection refrigerant is sent into the compression chamber by the pressure difference. For this reason, if the intermediate pressure is adjusted high, the injection rate increases. On the other hand, since the gas phase component ratio in the refrigerant flowing from the condenser through the upstream expansion valve to the gas-liquid separator decreases as the intermediate pressure increases, the gas-liquid separator increases when the intermediate pressure is excessively increased. The liquid refrigerant increases, and the liquid refrigerant flows into the injection pipe, resulting in a decrease in heating capacity and a decrease in the reliability of the compressor. Therefore, it is desirable for the compressor to be able to take in a large amount of injection refrigerant at the lowest possible intermediate pressure, and as the compression method, a scroll type with a moderate compression speed is suitable.

Above all, the symmetrical scroll compressor, in which compression chambers with the same volume are formed at the same timing on the outer and inner sides of the orbiting scroll wrap, has features such as low vibration and excellent mechanical balance due to the symmetry of the compression chamber. It has been used in various fields including air conditioning applications.

On the other hand, regarding the injection, the conventional scroll compressor discloses the opening range of the injection port and the bypass port (see, for example, Patent Document 1). Thereby, the scroll compressor which can respond | correspond with various performance modes including injection with sufficient performance is provided.

Japanese Patent No. 3764261

In the symmetric scroll compressor, the compression start timings of the first compression chamber formed outside the orbiting scroll wrap and the second compression chamber formed inside the orbiting scroll wrap are equal, and a single injection port is used. It is difficult to always feed the same amount of injection refrigerant into the first compression chamber and the second compression chamber.

Further, in Patent Document 1, although the relationship between the bypass port and the opening section of the injection port is disclosed, the relationship between the amount of injection into the first compression chamber and the second compression chamber and the bypass port is disclosed. Absent.

The present invention avoids over-compression operation due to the difference in injection amount that inevitably occurs in a symmetric scroll compressor, and maximizes the original effect of the injection cycle. Therefore, the present invention is highly efficient for operation at a higher injection rate. To provide a scroll compressor that can cope with the increase in capacity.

A scroll compressor according to the present invention includes a fixed scroll and a turning scroll in which a spiral wrap rises from an end plate. Form. Also, as the compression chamber, a first compression chamber formed on the outer wall side of the orbiting scroll wrap and a second compression chamber formed on the inner wall side of the orbiting scroll wrap are formed, and the suction volume of the first compression chamber Is substantially equal to the suction volume of the second compression chamber. In addition, a discharge port that discharges the refrigerant compressed in the compression chamber is provided at the center of the end plate of the fixed scroll, and a discharge bypass port that discharges the refrigerant compressed in the compression chamber is provided before the compression chamber communicates with the discharge port. Further, at least one injection port for injecting the intermediate pressure refrigerant into the first compression chamber and the second compression chamber is opened to the first compression chamber or the second compression chamber in the compression stroke after the suction refrigerant is closed. The end plate of the fixed scroll is provided at a position where it is inserted. Furthermore, of the first compression chamber and the second compression chamber, one of the compression chambers that increases the amount of refrigerant injected from the injection port is a compression chamber that can discharge the refrigerant in the compression chamber to the other compression chamber. The discharge bypass port is arranged so that the volume ratio, which is the ratio of the suction volume to the discharge volume, becomes small.

In this way, by performing many injections on the compression chamber with a small volume ratio, it is possible to increase the injection rate and maximize the injection cycle effect, and to obtain the efficiency improvement and capacity expansion effects over the conventional ones. .

FIG. 1 is a refrigeration cycle diagram provided with a scroll compressor according to a first embodiment of the present invention. FIG. 2 is a longitudinal sectional view of the scroll compressor according to the first embodiment of the present invention. FIG. 3 is an enlarged view of a main part of FIG. FIG. 4 is a view taken along line 4-4 in FIG. FIG. 5 is a view taken in the direction of arrows 5-5 in FIG. 6 is a view taken along line 6-6 in FIG. FIG. 7 is a graph showing the internal pressure of the compression chamber of the scroll compressor without the injection operation. FIG. 8 is an explanatory diagram showing the positional relationship between the oil supply path and the seal member accompanying the turning motion of the scroll compressor according to the first embodiment of the present invention. FIG. 9 is an explanatory view showing an opening state of an oil supply path and an injection port accompanying a turning motion of the scroll compressor according to the first embodiment of the present invention. FIG. 10 is a longitudinal sectional view of a scroll compressor according to the second embodiment of the present invention.

(First embodiment)
The scroll compressor according to the first embodiment of the present invention will be described below. In addition, this invention is not limited by the following this Embodiment.

FIG. 1 is a refrigeration cycle diagram provided with a scroll compressor according to this embodiment.

As shown in FIG. 1, the refrigeration cycle apparatus provided with the scroll compressor according to the present embodiment includes a compressor 91 that is a scroll compressor, a condenser 92, an evaporator 93,

expansion valves

94a and 94b, an injection pipe 95, And a gas-liquid separator 96.

The refrigerant that is the working fluid condensed in the condenser 92 is decompressed to an intermediate pressure by the upstream expansion valve 94a, and the gas-liquid separator 96 is connected to the gas phase component (gas refrigerant) and the liquid phase component (liquid refrigerant) of the intermediate pressure refrigerant. (Refrigerant). The liquid refrigerant whose pressure has been reduced to the intermediate pressure further passes through the expansion valve 94b on the downstream side, and is led to the evaporator 93 as a low-pressure refrigerant.

The liquid refrigerant sent to the evaporator 93 evaporates by heat exchange and is discharged as a gas refrigerant mixed with a gas refrigerant or a part of the liquid refrigerant. The refrigerant discharged from the evaporator 93 is taken into the compression chamber of the compressor 91.

On the other hand, the intermediate-pressure gas refrigerant separated by the gas-liquid separator 96 passes through the injection pipe 95 and is guided to the compression chamber in the compressor 91. Although not shown, a configuration may be provided in which a blocking valve or an expansion valve is provided in the injection pipe 95 to adjust and stop the injection pressure.

The compressor 91 compresses the low-pressure refrigerant flowing in from the evaporator 93, and in the compression process, the intermediate-pressure refrigerant of the gas-liquid separator 96 is injected (injected) into the compression chamber for compression, and the high-temperature high-pressure refrigerant is condensed from the discharge pipe. To the container 92.

The ratio between the gas phase component and the liquid phase component separated by the gas-liquid separator 96 is such that the larger the pressure difference between the inlet side pressure and the outlet side pressure of the expansion valve 94a provided on the upstream side, the larger the gas phase component, The smaller the degree of supercooling of the refrigerant at the outlet of the condenser 92, or the greater the degree of thirst, the more gas phase components.

On the other hand, since the amount of refrigerant sucked by the compressor 91 through the injection pipe 95 increases as the intermediate pressure increases, the amount of the refrigerant separated by the gas-liquid separator 96 exceeds the ratio of the gas phase components of the refrigerant from the injection pipe 95. When the refrigerant is sucked, the gas refrigerant in the gas-liquid separator 96 is exhausted and the liquid refrigerant flows into the injection pipe 95. In order to maximize the performance of the compressor 91, it is desirable that the gas refrigerant separated in the gas-liquid separator 96 is sucked into the compressor 91 from the injection pipe 95 without leaving any excess. However, since the liquid refrigerant flows into the compressor 91 from the injection pipe 95 when the equilibrium state is deviated, the compressor 91 needs to be configured to maintain high reliability even in such a case.

FIG. 2 is a longitudinal sectional view of the scroll compressor according to this embodiment. FIG. 3 is an enlarged view of a main part of FIG. FIG. 4 is a view taken along line 4-4 of FIG. FIG. 5 is a view taken along line 4-4 in FIG.

2, the compressor 91 includes a compression mechanism 2, a motor unit 3, and an oil storage unit 20 inside the sealed container 1.

The compression mechanism 2 includes a main bearing member 11 fixed to the sealed container 1 by welding or shrink fitting, a fixed scroll (compression chamber partition member) 12 bolted on the main bearing member 11, and a turning scroll 13 meshing with the fixed scroll 12. And have. The shaft 4 is pivotally supported by the main bearing member 11.

Between the orbiting scroll 13 and the main bearing member 11, there is provided a rotation restraint mechanism 14 such as an Oldham ring that guides the orbiting scroll 13 to rotate and prevent it from rotating.

The orbiting scroll 13 is eccentrically driven by the eccentric shaft portion 4 a at the upper end of the shaft 4, and moves in a circular orbit by the rotation restraint mechanism 14.

The compression chamber 15 is formed between the fixed scroll 12 and the orbiting scroll 13.

The suction pipe 16 communicates with the outside of the sealed container 1, and a suction port 17 is provided on the outer periphery of the fixed scroll 12. The working fluid (refrigerant) sucked from the suction pipe 16 is guided from the suction port 17 to the compression chamber 15. The compression chamber 15 moves while reducing its volume from the outer peripheral side toward the central portion, and the working fluid that has reached a predetermined pressure in the compression chamber 15 is discharged from the discharge port 18 provided in the central portion of the fixed scroll 12 to the discharge chamber 31. Discharged. The discharge port 18 is provided with a discharge reed valve 19. The working fluid that has reached a predetermined pressure in the compression chamber 15 pushes the discharge reed valve 19 open and is discharged into the discharge chamber 31. The working fluid discharged into the discharge chamber 31 is discharged out of the sealed container 1.

On the other hand, the intermediate-pressure working fluid led from the injection pipe 95 flows into the intermediate pressure chamber 41, opens the check valve 42 provided in the injection port 43, and is injected into the compression chamber 15 after being closed, and the suction port Together with the working fluid sucked from 17, it is discharged into the sealed container 1 from the discharge port 18.

A pump 25 is provided at the lower end of the shaft 4. The pump 25 is arranged so that the suction port exists in the oil storage unit 20. The pump 25 is driven by the shaft 4 and can reliably suck up the oil 6 in the oil storage section 20 provided at the bottom of the hermetic container 1 regardless of the pressure condition and the operation speed. It will be resolved. The oil 6 sucked up by the pump 25 is supplied to the compression mechanism 2 through an oil supply hole 26 formed in the shaft 4. If foreign matter is removed from the oil 6 with an oil filter or the like before or after the oil 25 is sucked up by the pump 25, foreign matter can be prevented from entering the compression mechanism 2 and further reliability can be improved.

The pressure of the oil 6 guided to the compression mechanism 2 is substantially equal to the discharge pressure of the scroll compressor, and also serves as a back pressure source for the orbiting scroll 13. As a result, the orbiting scroll 13 does not move away from the fixed scroll 12 and does not come into contact with each other, and the predetermined compression function is stably exhibited.

As shown in FIG. 3, a ring-shaped seal member 78 is disposed on the back surface 13 e of the end plate of the orbiting scroll 13.

The high pressure region 30 is formed inside the seal member 78, and the back pressure chamber 29 is formed outside the seal member 78. The back pressure chamber 29 is set to a pressure between a high pressure and a low pressure. By using the seal member 78, the high pressure region 30 and the back pressure chamber 29 can be separated, so that pressure application from the back surface 13e of the orbiting scroll 13 can be stably controlled.

As shown in FIG. 6 as viewed in the direction of arrows 6-6 in FIG. 3, the compression chamber 15 formed by the fixed scroll 12 and the orbiting scroll 13 is formed on the outer wall side of the wrap of the orbiting scroll 13. There are a first compression chamber 15a and a second compression chamber 15b formed on the inner wall side of the wrap.

3 includes a connecting path 55 from the high pressure region 30 to the back pressure chamber 29 and a supply path 56 from the back pressure chamber 29 to the second compression chamber 15b. By providing the connection path 55 from the high pressure region 30 to the back pressure chamber 29, the oil 6 can be supplied to the sliding portion of the rotation restraint mechanism 14 and the thrust sliding portion of the fixed scroll 12 and the orbiting scroll 13.

One first opening end 55 a of the connection path 55 is formed on the back surface 13 e of the orbiting scroll 13, and travels between the inside and outside of the seal member 78, and the other second opening end 55 b always opens to the high-pressure region 30. Yes. Thereby, intermittent oil supply is realizable.

A part of the oil 6 enters the fitting portion between the eccentric shaft portion 4a and the orbiting scroll 13 and the bearing portion 66 between the shaft 4 and the main bearing member 11 so as to obtain a clearance by the supply pressure and the own weight. After lubricating each part, it falls and returns to the oil storage part 20.

In the scroll compressor according to the present embodiment, the oil supply path to the compression chamber 15 is configured by a passage 13 a formed inside the orbiting scroll 13 and a recess 12 a formed on the lap surface side end plate of the fixed scroll 12. Yes. The third opening end 56a of the passage 13a is formed at the lap tip 13c, and is periodically opened in the recess 12a according to the turning motion, and the fourth opening end 56b of the passage 13a is always opened in the back pressure chamber 29. . Thereby, the back pressure chamber 29 and the 2nd compression chamber 15b can be intermittently connected.

The injection port 43 for injecting the intermediate pressure refrigerant is provided through the end plate of the fixed scroll 12. The injection port 43 opens sequentially to the first compression chamber 15a and the second compression chamber 15b. The injection port 43 is provided at a position that is opened during the compression process after being closed in the first compression chamber 15a and the second compression chamber 15b.

The end plate of the fixed scroll 12 is provided with a discharge bypass port 21 that discharges the refrigerant compressed in the compression chamber 15 before communicating with the discharge port 18.

As shown in FIGS. 3 to 4, the compressor 91 according to the present embodiment is provided with an intermediate pressure chamber 41 that is fed from the injection pipe 95 and guides the intermediate pressure working fluid before being injected into the compression chamber 15.

The intermediate pressure chamber 41 is formed by a fixed scroll 12 that is a compression chamber partition member, an intermediate pressure plate 44, and an intermediate pressure cover 45. The intermediate pressure chamber 41 and the compression chamber 15 are opposed to each other with the fixed scroll 12 interposed therebetween. The intermediate pressure chamber 41 is located at a position lower than the intermediate pressure chamber inlet 41a into which the intermediate pressure working fluid flows, the injection port inlet 43a of the injection port 43 that injects the intermediate pressure working fluid into the compression chamber 15, and the intermediate pressure chamber inlet 41a. The liquid reservoir 41b is formed.

The liquid reservoir 41b is formed on the upper surface of the end plate of the fixed scroll 12.

The intermediate pressure plate 44 is provided with a check valve 42 for preventing a refrigerant backflow from the compression chamber 15 to the intermediate pressure chamber 41. In the section where the injection port 43 is open to the compression chamber 15, if the internal pressure of the compression chamber 15 is higher than the intermediate pressure of the injection port 43, the refrigerant flows backward from the compression chamber 15 toward the intermediate pressure chamber 41. The reverse flow of the refrigerant can be prevented by providing the check valve 42.

In the compressor 91 according to the present embodiment, the check valve 42 is configured by a reed valve 42a that lifts to the compression chamber 15 side and communicates the compression chamber 15 and the intermediate pressure chamber 41, and the internal pressure of the compression chamber 15 is intermediate. The intermediate pressure chamber 41 is communicated with the compression chamber 15 only when the pressure is lower than the pressure chamber 41. By using the reed valve 42a, there are few sliding parts in a movable part, a sealing performance can be maintained for a long time, and it is easy to expand a flow path area as needed. When the check valve 42 is not provided or the check valve 42 is provided in the injection pipe 95, the refrigerant in the compression chamber 15 flows back to the injection pipe 95, and wasteful compression power is consumed. In the present embodiment, the check valve 42 is provided on the intermediate pressure plate 44 close to the compression chamber 15 to suppress the backflow from the compression chamber 15.

The upper surface of the end plate of the fixed scroll 12 is at a position lower than the intermediate pressure chamber inlet 41a, and a liquid reservoir 41b in which a working fluid of a liquid phase component is provided on the upper surface of the end plate of the fixed scroll 12. Further, the injection port inlet 43a is provided at a position higher than the height of the intermediate pressure chamber inlet 41a. Therefore, among the intermediate pressure working fluid, the working fluid of the gas phase component is guided to the injection port 43, and the working fluid of the liquid phase component accumulated in the liquid reservoir 41b is vaporized on the surface of the fixed scroll 12 in a high temperature state. Therefore, it is difficult for the working fluid of the liquid phase component to flow into the compression chamber 15.

Further, the intermediate pressure chamber 41 and the discharge chamber 31 are provided at positions adjacent to each other via the intermediate pressure plate 44, and promotes vaporization when the working fluid of the liquid phase component flows into the intermediate pressure chamber 41, and discharges. Since the temperature rise of the high-pressure refrigerant in the chamber 31 can also be suppressed, the operation can be performed up to a higher discharge pressure condition.

The intermediate pressure working fluid guided to the injection port 43 pushes and opens the reed valve 42 a due to a pressure difference between the injection port 43 and the compression chamber 15, and merges with the low pressure working fluid sucked from the suction port 17 in the compression chamber 15. However, the intermediate pressure working fluid remaining in the injection port 43 between the check valve 42 and the compression chamber 15 repeats re-expansion and re-compression, which causes a reduction in the efficiency of the compressor 91. Therefore, the thickness of the valve stop 42b (see FIG. 5) that regulates the maximum displacement amount of the reed valve 42a is changed according to the lift restricting portion of the reed valve 42a, and the volume in the injection port 43 downstream from the reed valve 42a is reduced. is doing.

Further, the reed valve 42a and the valve stop 42b shown in FIG. 5 are fixed to the intermediate pressure plate 44 by a fixing member 46 including a bolt. Since the fixing hole of the fixing member 46 including the screw provided in the valve stop 42b is opened only on the insertion side of the fixing member 46 without penetrating the valve stop 42b, the fixing member 46 becomes an intermediate pressure chamber as a result. 41 is configured to open only to 41. Thereby, it can suppress that a working fluid leaks between the intermediate | middle pressure chamber 41 and the compression chamber 15 via the clearance gap between the fixing members 46, and can improve an injection rate.

The intermediate pressure chamber 41 shown in FIG. 3 has a suction volume equal to or larger than the suction volume of the compression chamber 15 so that the injection amount into the compression chamber 15 can be sufficiently supplied. Here, the suction volume is the volume of the compression chamber 15 when the working fluid guided from the suction port 17 is closed in the compression chamber 15, that is, when the suction process is completed, and the first compression chamber 15a and the second compression chamber. The total volume with 15b. In the compressor 91 of the present embodiment, the intermediate pressure chamber 41 is provided so as to spread on the plane of the end plate of the fixed scroll 12 to increase the volume. However, when a part of the oil 6 sealed in the compressor 91 comes out of the compressor 91 together with the discharged refrigerant and returns to the intermediate pressure chamber 41 from the gas-liquid separator 96 through the injection pipe 95, the liquid reservoir If too much oil 6 remains in the portion 41b, there will be a problem that the oil 6 in the oil storage portion 20 will be insufficient. Therefore, it is not appropriate that the volume of the intermediate pressure chamber 41 is too large. Therefore, the volume of the intermediate pressure chamber 41 is preferably not less than the suction volume of the compression chamber 15 and not more than ½ of the oil volume of the sealed oil 6.

FIG. 6 is a view taken along line 6-6 in FIG.

FIG. 6 is a view of the orbiting scroll 13 engaged with the fixed scroll 12 and viewed from the back surface 13e side of the orbiting scroll 13. FIG. As shown in FIG. 6, the number of turns of the spiral wrap of the fixed scroll 12 and the spiral wrap of the orbiting scroll 13 are equal in a state where the fixed scroll 12 and the orbiting scroll 13 are engaged with each other.

The compression chamber 15 formed by the fixed scroll 12 and the orbiting scroll 13 includes a first compression chamber 15a formed on the outer wall side of the wrap of the orbiting scroll 13 and a second compression chamber 15b formed on the inner wall side of the wrap. There is.

The timing for confining the working fluid in the first compression chamber 15a and the timing for confining the working fluid in the second compression chamber 15b are substantially equal, and the first compression chamber 15a and the second compression chamber 15b start compression simultaneously. Thereby, the pressure balance between the 1st compression chamber 15a and the 2nd compression chamber 15b is maintained, and the behavior of the turning scroll 13 is stabilized.

In FIG. 7, R is a pressure curve showing the internal pressure of the compression chamber of the scroll compressor without injection operation.

When the injection operation is not involved, the pressure increasing speeds of the first compression chamber 15a and the second compression chamber 15b with respect to the crank rotation angle are equal. However, when the amount of injection into the first compression chamber 15a and the second compression chamber 15b is different, the pressure increase speed varies depending on the amount of injection.

Fig. 7 shows the difference in compression speed due to the difference in injection amount. In the compression chamber with a large injection amount, the discharge pressure is reached in a short compression section from the start of compression. In the present embodiment, since the injection refrigerant amount to the first compression chamber 15a is increased, the pressure increase rate of the first compression chamber 15a shown in the pressure curve P is the pressure increase rate of the second compression chamber 15b shown in the pressure curve Q. Will be faster. In FIG. 7, when the discharge bypass port 21 is provided in accordance with the internal pressure of the compression chamber with a small injection amount shown in the pressure curve Q, the internal pressure of the compression chamber with a large injection amount shown in the pressure curve P is the internal pressure shown in the pressure curve Q. Reach the discharge pressure faster. However, overcompression occurs in the first compression chamber 15a that continues to compress without escape after reaching the discharge pressure, and the overcompression is alleviated after communicating with the discharge bypass port 21. That is, extra compression power corresponding to the area A in the figure is required. Therefore, in the present invention, the discharge bypass port 21 is provided at a position where the first compression chamber 15a having a large injection amount can be discharged at an earlier timing than the second compression chamber 15b.

That is, in the compression chamber having a large injection amount, the internal pressure of the compression chamber is increased by the injection refrigerant, and in the compression chamber in which the injection amount is small or not injected, the pressure increase is slower than the other. In other words, for the compression chamber with a large injection amount, it is necessary to make it possible to discharge from an earlier timing than the other compression chamber, but in the symmetrical scroll compression in which the injection amount is necessarily different, If the injection operation is performed without taking such consideration into consideration, the efficiency decreases. In the present embodiment, the discharge bypass port 21 is provided at a position where the first compression chamber 15a having a large injection amount can be discharged at an earlier timing than the second compression chamber 15b. Thus, the volume ratio defined by the ratio of the suction volume of the compression chamber to the volume of the compression chamber that allows the refrigerant to be discharged by communicating with the discharge port or the discharge bypass port 21 is the first compression with a large injection amount. It is made small in the chamber 15a.

As shown in FIG. 7, the opening section of the injection port 43 to the second compression chamber 15b overlaps at least a part of the oil supply section from the back pressure chamber 29 to the second compression chamber 15b. The overlapping section in which the fueling section overlaps with the opening section is a partial section in the latter half of the fueling section, and the injection port 43 opens in the latter half of the fueling section and the opening section starts.

Further, the lap tip 13c of the orbiting scroll 13 is gradually increased in height from the winding start portion which is the central portion to the winding end portion which is the outer peripheral portion based on the measurement result of the temperature distribution during operation. A slope shape is provided so as to be. This absorbs a dimensional change due to thermal expansion and facilitates preventing local sliding.

FIG. 8 is an explanatory diagram showing the positional relationship between the oil supply path and the seal member accompanying the turning motion of the scroll compressor according to the present embodiment.

FIG. 8 shows a state in which the orbiting scroll 13 is engaged with the fixed scroll 12 and viewed from the back surface 13e side of the orbiting scroll 13, and the phase is shifted by 90 degrees.

The first opening end 55 a of the connection path 55 is formed on the back surface 13 e of the orbiting scroll 13.

As shown in FIG. 8, the back surface 13 e of the orbiting scroll 13 is partitioned by the seal member 78 into an inner high pressure region 30 and an outer back pressure chamber 29.

8 (B), the first opening end 55a is open to the back pressure chamber 29 that is outside the seal member 78, so that the oil 6 is supplied.

On the other hand, in FIGS. 8A, 8C, and 8D, the first opening end 55a is opened inside the seal member 78, so that no oil is supplied.

That is, the first opening end 55a of the connection path 55 travels between the high pressure region 30 and the back pressure chamber 29, but only when a pressure difference occurs between the first opening end 55a and the second opening end 55b of the connection path 55. Oil 6 is supplied to the pressure chamber 29. With this configuration, the amount of oil supply can be adjusted by the time ratio at which the first opening end 55a travels between the inside and the outside of the seal member 78. Therefore, the passage diameter of the connection passage 55 is configured to be 10 times or more that of the oil filter. It becomes possible. As a result, there is no possibility of foreign matter getting caught in the passage 13a, so that the thrust sliding portion and the rotation restraint mechanism 14 can be kept in good lubrication simultaneously with the stable application of the back pressure, and highly efficient and highly reliable. A scroll compressor that realizes performance can be provided. In the present embodiment, the case where the second opening end 55b is always in the high pressure region 30 and the first opening end 55a travels between the high pressure region 30 and the back pressure chamber 29 has been described as an example. Even when the first opening end 55a is always in the back pressure chamber 29, the pressure difference occurs between the first opening end 55a and the second opening end 55b, so that intermittent lubrication is realized. The same effect can be obtained.

FIG. 9 is an explanatory diagram showing an oil supply path and an injection port opening state associated with the turning motion of the scroll compressor according to the present embodiment.

FIG. 9 shows a state where the orbiting scroll 13 is engaged with the fixed scroll 12, and the phase is shifted by 90 degrees.

As shown in FIG. 9, intermittent communication is realized by periodically opening the third opening end 56 a of the passage 13 a formed in the wrap tip 13 c into the recess 12 a formed in the end plate of the fixed scroll 12. Yes.

In the state of FIG. 9D, the third opening end 56a opens into the recess 12a. In this state, the oil 6 passes from the back pressure chamber 29 to the second compression chamber 15b through the supply path 56 and the passage 13a. Supplied. Thus, the oil supply path is provided by the third opening end 56a at a position that opens to the second compression chamber 15b in the compression stroke after the intake refrigerant is closed.

On the other hand, in FIGS. 9A, 9 </ b> B, and 9 </ b> C, the third opening end 56 a is not opened in the recess 12 a, so that the oil 6 is not supplied from the back pressure chamber 29 to the second compression chamber 15 b. . From the above, since the oil 6 in the back pressure chamber 29 is intermittently guided to the second compression chamber 15b through the oil supply path, the pressure fluctuation in the back pressure chamber 29 can be suppressed, and the predetermined pressure can be maintained. It becomes possible to control. At the same time, the oil 6 supplied to the second compression chamber 15b plays a role of improving the sealing property and the lubricating property during compression.

In FIG. 9C showing the closing time of the first compression chamber 15a, the injection port 43 is open to the first compression chamber 15a.

On the other hand, with respect to the second compression chamber 15b, the injection port 43 opens in the state shown in FIG. Thereby, the opening section of the injection port 43 is substantially equal as the section between the first compression chamber 15a and the second compression chamber 15b, but the first compression chamber 15a is performing injection into the compression chamber having a low pressure immediately after the start of compression. In this case, more injection refrigerant is fed, and the pressure increase in the first compression chamber 15a is accelerated relative to the second compression chamber 15b. Moreover, since the injection refrigerant can be compressed without flowing back to the suction port 17 in any of the compression chambers, it is easy to increase the amount of refrigerant circulation, and a highly efficient injection operation is possible.

Thus, the injection port 43 is provided at a position that sequentially opens into the first compression chamber 15a and the second compression chamber 15b. Further, as shown in FIGS. 9C and 9D, the injection port 43 is opened to the first compression chamber 15a during the compression stroke after the intake refrigerant is closed, or FIG. 9A. (B), the end plate of the fixed scroll 12 is provided so as to penetrate the second compression chamber 15b in the compression stroke after the suction refrigerant is closed.

In FIG. 9, the oil supply section starts from (C) to (D) in FIG. 9, and the injection port 43 opens to the second compression chamber 15 b between (A) and (B) in FIG. The opening section of the injection port 43 has an overlapping section with the refueling section. In the present embodiment, the oil supply section is equal to the opening of the third opening end 56a into the recess 12a. The pressure in the back pressure chamber 29 depends on the internal pressure of the compression chamber 15 at the end of the oil supply section, and the injection refrigerant is fed into the compression chamber 15 from the middle of the oil supply section, so that the pressure in the back pressure chamber 29 is only during the injection operation. Can be suppressed, and instability of the behavior of the orbiting scroll 13 can be suppressed. Further, as a reason why the start of opening of the injection port 43 cannot be advanced to the first half of the oil supply section, if the internal pressure of the compression chamber 15 is excessively increased by the injection refrigerant from the early stage of the oil supply section, sufficient oil supply from the back pressure chamber 29 to the compression chamber 15 is performed. Before the operation is performed, the internal pressure of the compression chamber 15 and the pressure of the back pressure chamber 29 become equal, and there is a high possibility of causing a problem in the reliability of the compressor due to insufficient lubrication.

少なくとも At least part of the oil supply section to the compression chamber 15 is configured to overlap with the opening section of the injection port 43. With this configuration, the pressure applied from the back surface 13e to the orbiting scroll 13 increases with the internal pressure of the compression chamber 15 in the oil supply section as the intermediate pressure of the injection refrigerant increases. Therefore, the orbiting scroll 13 is more stably pressed against the fixed scroll 12, reducing leakage from the back pressure chamber 29 to the compression chamber 15 and performing stable operation. Thereby, the behavior of the orbiting scroll 13 can be realized more stably, the optimum performance can be realized, and the injection rate can be further improved.

In FIG. 9, a discharge port 18 that discharges the refrigerant compressed in the compression chamber 15 is provided at the center of the end plate of the fixed scroll 12, and a discharge bypass provided as a discharge bypass port 21 at a position communicating with the first compression chamber 15a. A port 21a and a discharge bypass port 21b provided at a position communicating with the second compression chamber 15b are provided.

The first compression chamber 15a closes the intake refrigerant in the state of FIG. 9C, and the discharge bypass port 21a opens to the first compression chamber 15a in the state of FIG. 9D.

On the other hand, the second compression chamber 15b closes the suction refrigerant in the state of FIG. 9C, but the discharge bypass port 21b is still in the second compression chamber 15b in the states of FIG. 9D and FIG. Is not communicated, and is in the state of FIG. 9B and communicates with the second compression chamber 15b. Thereby, even if the 1st compression chamber 15a takes in more injection refrigerant | coolants with respect to the 2nd compression chamber 15b, it can exhibit the effect of an injection cycle, without overcompressing.

Thus, the provision of the discharge bypass port 21a that communicates with the first compression chamber 15a and the discharge bypass port 21b that communicates with the second compression chamber 15b also allows the refrigerant in the compression chamber 15 to be discharged. The volume ratio that is the ratio of the suction volume to the discharge volume can be made smaller in the first compression chamber 15a than in the second compression chamber 15b. Therefore, an excessive pressure increase in the first compression chamber 15a can be suppressed even in the maximum injection state.

(Second Embodiment)
FIG. 10 is a longitudinal sectional view of a scroll compressor according to the second embodiment of the present invention.

In the present embodiment, a first injection port 48a that opens only to the first compression chamber 15a and a second injection port 48b that opens only to the second compression chamber 15b are provided. A first check valve 47a is provided in the first injection port 48a, and a second check valve 47b is provided in the second injection port 48b. Since other configurations are the same as those in the above embodiment, the same reference numerals are given and description thereof is omitted.

In the present embodiment, by making the port diameter of the first injection port 48a larger than that of the second injection port 48b, the amount of refrigerant injected from the first injection port 48a into the first compression chamber 15a can be reduced from the second injection port 48b. The amount of refrigerant injected into the second compression chamber 15b is larger.

Thus, by providing the first injection port 48a that opens only to the first compression chamber 15a and the second injection port 48b that opens only to the second compression chamber 15b, the first compression chamber 15a and the second compression chamber 15b are provided. It becomes possible to individually adjust the injection amount. Further, it is possible to always inject the first compression chamber 15a and the second compression chamber 15b, or simultaneously inject the first compression chamber 15a and the second compression chamber 15b, and the pressure difference of the refrigeration cycle is large. It is effective to realize a high injection rate under certain conditions. Further, since the degree of freedom in setting the oil supply section from the back pressure chamber 29 is increased, the pressure adjustment function from the back pressure chamber 29 can be effectively utilized, and the pressure application from the back surface 13e of the orbiting scroll 13 can be stably performed. Can be controlled.

In the present embodiment, the case where the first injection port 48a has a larger port diameter than the second injection port 48b is shown. However, together with this configuration or instead of this configuration, the opening section where the first injection port 48a opens to the first compression chamber 15a is longer than the opening section where the second injection port 48b opens to the second compression chamber 15b. May be. Further, when the first injection port 48a is opened to the first compression chamber 15a, the pressure difference between the intermediate pressure in the first injection port 48a and the internal pressure in the first compression chamber 15a is the second compression chamber of the second injection port 48b. The pressure difference between the intermediate pressure in the second injection port 48b and the internal pressure of the second compression chamber 15b at the time of opening to 15b can be made larger.

In the present embodiment, the first injection port 48a and the second injection port 48b that open only to the first compression chamber 15a and the second compression chamber 15b have been described. However, only the injection ports opened in both the first compression chamber 15a and the second compression chamber 15b shown in the first embodiment, and the first compression chamber 15a and the second compression chamber 15b shown in the present embodiment, respectively. The first injection port 48a and the second injection port 48b that are opened may be combined to increase the amount of injection into the first compression chamber 15a than the amount of injection into the second compression chamber 15b.

When R32 or carbon dioxide, which is likely to have a high temperature of the discharged refrigerant, is used as the refrigerant that is the working fluid, the effect of suppressing an increase in the discharged refrigerant temperature is exhibited, and the insulating material of the motor unit 3 (see FIG. 2) It is possible to provide a highly reliable compressor over a long period of time by suppressing deterioration of the resin material.

On the other hand, when a refrigerant having a double bond between carbons or a refrigerant of GWP500 or less (GWP: Global Warming Potential) containing the refrigerant is used, a refrigerant decomposition reaction easily occurs at a high temperature. The effect of suppressing the rise in the discharged refrigerant temperature is effective in the long-term stability of the refrigerant.

As described above, the scroll compressor according to the first disclosure includes the discharge port that discharges the refrigerant compressed in the compression chamber at the center of the end plate of the fixed scroll, and compresses the compression chamber before it communicates with the discharge port. A discharge bypass port for discharging the refrigerant compressed in the chamber is provided. Further, at least one injection port for injecting the intermediate pressure refrigerant into the first compression chamber and the second compression chamber is opened to the first compression chamber or the second compression chamber in the compression stroke after the suction refrigerant is closed. The end plate of the fixed scroll is provided at a position where it is inserted. Further, of the first compression chamber and the second compression chamber, one compression chamber that increases the amount of refrigerant injected from the injection port is connected to the other compression chamber so that the refrigerant in the compression chamber can be discharged. The discharge bypass port is arranged so that the volume ratio, which is the ratio of the suction volume to the discharge volume, becomes small.

According to the present disclosure, in the scroll compressor in which the discharge volume and the suction volume are the same in the first compression chamber and the second compression chamber, the volume ratio of the first compression chamber and the second compression chamber is also equal, By performing more injections, the internal pressure of the compression chamber reaches the discharge pressure in a shorter compression section than the other compression chamber. Even if the internal pressure of the compression chamber reaches the discharge pressure, if the dischargeable port and the compression chamber do not communicate with each other, excessive compression occurs, requiring not only excessive compression power, but also pulling the orbiting scroll away from the fixed scroll This generates force, leading to instability of the compression motion. By disposing the discharge bypass port so that the volume ratio of one compression chamber that increases the amount of refrigerant to be injected is smaller than that of the other compression chamber, excessive pressure rise is suppressed even in the maximum injection state. Can do. In other words, according to the present embodiment, by connecting the discharge bypass port to the compression chamber with a large injection amount at an early stage and reducing the volume ratio, over-compression can be prevented even during operation at a high injection rate. By maximizing the cycle effect, it becomes possible to obtain an efficiency improvement and capacity expansion effect that are more than conventional.

According to a second disclosure, in the scroll compressor according to the first disclosure, the injection port is provided with a check valve that allows a refrigerant flow to the compression chamber and inhibits the refrigerant flow from the compression chamber.

According to the present disclosure, by providing the check valve and the compression chamber close to each other, even if the internal pressure of the compression chamber rises above the intermediate pressure in the section where the injection port is open to the compression chamber, the compression of the injection pipe or the like Therefore, it is possible to minimize the refrigerant compression in the space that is ineffective, and to increase the injection rate up to the condition where the theoretical performance of the injection cycle can be maximized.

According to a third disclosure, in the scroll compressor according to the first disclosure or the second disclosure, an oil storage part for storing oil is formed in a sealed container having a fixed scroll and a turning scroll therein, and a high pressure is provided on a rear surface of the turning scroll. An area and a back pressure chamber are formed. In addition, the oil supply path for supplying oil from the oil storage section to the compression chamber passes through the back pressure chamber, and the oil supply path in which the back pressure chamber communicates with the first compression chamber or the second compression chamber is the compression after the suction refrigerant is closed. It is provided at a position that opens to the first compression chamber or the second compression chamber during the stroke. Further, at least a part of the oil supply section in which the oil supply path communicates with the first compression chamber or the second compression chamber is overlapped with the opening section where the injection port opens into the first compression chamber or the second compression chamber.

When intermediate pressure refrigerant is injected into the compression chamber, the pressure in the compression chamber rises faster than when injection is not performed, so the force for pulling the orbiting scroll away from the fixed scroll is greater than before. According to the present disclosure, the force that presses the orbiting scroll to the fixed scroll is linked to the pressure in the compression chamber that communicates with the oil supply path, so that the more intermediate pressure refrigerant is injected into the compression chamber, the more the orbiting scroll The force that pushes the fixed scroll to the fixed scroll is also increased, and the orbiting scroll can be stably operated without leaving the fixed scroll.

In the fourth disclosure, in the scroll compressor according to the third disclosure, an overlapping section in which the fueling section overlaps with the opening section is defined as a part of the latter half of the fueling section.

According to the present disclosure, since the pressure in the back pressure chamber is linked to the internal pressure in the compression chamber in the latter half of the overlapping section, the back pressure chamber pressure corresponding to the internal pressure in the compression chamber in a state where injection has been completed or more injected Can be set. As a result, the pressure in the back pressure chamber is high under conditions where the revolving force of the orbiting scroll due to injection is large, and stable orbiting is possible, while the pressure in the back pressure chamber is low under conditions where the amount of injection is small, It is possible to prevent excessive pressing force.

According to a fifth disclosure, in the scroll compressor according to any one of the first disclosure to the fourth disclosure, at least one injection port is provided at a position that sequentially opens into the first compression chamber and the second compression chamber.

According to the present disclosure, since the injection port can be shared when injecting into both the first compression chamber and the second compression chamber, not only can the size and the number of components be reduced, but also the injection rate can be increased. It is possible to maximize the injection cycle effect. Further, in the scroll compressor, since the compression start timing is generally 180 degrees different between the first compression chamber and the second compression chamber, a position where injection is performed immediately after the start of compression from any one injection port to any compression chamber. It is also possible to provide a high injection rate.

A sixth disclosure is a scroll compressor according to any one of the first to fourth disclosures, and as the injection port, a first injection port that opens only in the first compression chamber, and a second And a second injection port that opens only to the compression chamber. Further, any one of the following configurations (1) to (3) is added.
(1) The first injection port has a larger port diameter than the second injection port.
(2) The opening section where the first injection port opens into the first compression chamber is longer than the opening section where the second injection port opens into the second compression chamber.
(3) The pressure difference between the intermediate pressure in the first injection port and the internal pressure in the first compression chamber when the first injection port opens into the first compression chamber is the opening of the second injection port into the second compression chamber. The pressure difference between the intermediate pressure in the second injection port and the internal pressure in the second compression chamber at the time is larger.

According to the present disclosure, the amount of injection into the first compression chamber having a large volume and a slow pressure increase rate can be surely increased, and an efficient injection refrigerant amount can be distributed.

The scroll compressor of the present invention is useful for a refrigeration cycle apparatus such as a hot water heater, an air conditioner, a water heater, or a refrigerator in which an evaporator is used in a low temperature environment.

DESCRIPTION OF SYMBOLS 1 Airtight container 2 Compression mechanism 3 Motor part 4 Shaft 4a Eccentric shaft part 6 Oil 11 Main bearing member 12 Fixed scroll 12a Recessed part 13 Orbiting scroll

13c Lap tip

13e Back surface 14 Rotation restraint mechanism 15 Compression chamber 15a 1st compression chamber 15b 2nd compression Chamber 16 Suction pipe 17 Suction port 18 Discharge port 19 Discharge reed valve 20

Oil storage part

21, 21a, 21b Discharge bypass port 25 Pump 26 Oil supply hole 29 Back pressure chamber 30 High pressure region 31 Discharge chamber 41 Intermediate pressure chamber 41a Intermediate pressure chamber inlet 41b Liquid reservoir 42 Check valve 42a Reed valve 42b Valve stop 43 Injection port 43a Injection port inlet 44 Intermediate pressure plate (intermediate pressure chamber partition member)
45 Intermediate pressure cover (intermediate pressure chamber partition member)
46 fixing member 47a first check valve 47b second check valve 48 injection port 48a first injection port 48b second injection port 55 connection path 55a first opening end 55b second opening end 56 supply path 56a third opening end 56b 4th opening end 66 Bearing part 78 Seal member 91 Compressor 92 Condenser 93

Evaporator

94a, 94b Expansion valve 95 Injection pipe 96 Gas-liquid separator

Claims

A fixed scroll and a orbiting scroll in which a spiral wrap rises from an end plate, and a compression chamber is formed between the fixed scroll and the orbiting scroll by meshing the wrap of the fixed scroll and the wrap of the orbiting scroll. The first compression chamber formed on the outer wall side of the wrap of the orbiting scroll and the second compression chamber formed on the inner wall side of the wrap of the orbiting scroll are formed as the compression chamber, In the scroll compressor, the suction volume of one compression chamber is equal to the suction volume of the second compression chamber,
A discharge port that discharges the refrigerant compressed in the compression chamber is provided at the center of the end plate of the fixed scroll, and discharge that discharges the refrigerant compressed in the compression chamber before the compression chamber communicates with the discharge port. The first compression chamber or the first compression chamber that is in the compression stroke after the intake refrigerant is closed by providing a bypass port and injecting intermediate pressure refrigerant into the first compression chamber and the second compression chamber The first compression chamber and the second compression chamber are provided at positions that open to the second compression chamber so as to penetrate the end plate, and the first compression chamber and the second compression chamber increase the amount of refrigerant injected from the injection port. Either one of the first compression chamber and the second compression chamber discharges the refrigerant in the compression chamber from the other of the first compression chamber and the second compression chamber. Scroll compressor, wherein a volume ratio which is the ratio of the suction volume is arranged the discharge bypass port so as to be smaller for the discharge volume of the compression chamber becomes possible.
2. The scroll compression according to claim 1, wherein the injection port is provided with a check valve that allows the flow of the refrigerant to the compression chamber and inhibits the flow of the refrigerant from the compression chamber. Machine.
The sealed container having the fixed scroll and the orbiting scroll is provided with an oil storage part for storing oil, and a high pressure region and a back pressure chamber are formed on the rear surface of the orbiting scroll, and the compression is performed from the oil storage part. An oil supply path for supplying the oil to the chamber passes through the back pressure chamber, and the oil supply path in which the back pressure chamber communicates with the first compression chamber or the second compression chamber is provided after the intake refrigerant is closed. Provided at the position that opens to the first compression chamber or the second compression chamber in the compression stroke, and the oil supply path is at least part of the oil supply section that communicates with the first compression chamber or the second compression chamber. The scroll compressor according to claim 1, wherein a section is overlapped with an opening section where the injection port opens into the first compression chamber or the second compression chamber.
The sealed container having the fixed scroll and the orbiting scroll is provided with an oil storage part for storing oil, and a high pressure region and a back pressure chamber are formed on the rear surface of the orbiting scroll, and the compression is performed from the oil storage part. An oil supply path for supplying the oil to the chamber passes through the back pressure chamber, and the oil supply path in which the back pressure chamber communicates with the first compression chamber or the second compression chamber is provided after the intake refrigerant is closed. Provided at the position that opens to the first compression chamber or the second compression chamber in the compression stroke, and the oil supply path is at least part of the oil supply section that communicates with the first compression chamber or the second compression chamber. The scroll compressor according to claim 2, wherein a section is overlapped with an opening section where the injection port opens into the first compression chamber or the second compression chamber.
The scroll compressor according to claim 3, wherein an overlapping section in which the refueling section overlaps with the opening section is a partial section in the latter half of the refueling section.
The scroll compressor according to claim 4, wherein an overlapping section in which the fueling section overlaps with the opening section is a part of the latter half of the fueling section.
The scroll compression according to any one of claims 1 to 6, wherein at least one of the injection ports is provided at a position that sequentially opens into the first compression chamber and the second compression chamber. Machine.
The injection port includes a first injection port that opens only to the first compression chamber, and a second injection port that opens only to the second compression chamber, and the first injection port is more than the second injection port. Or the opening section where the first injection port opens into the first compression chamber is longer than the opening section where the second injection port opens into the second compression chamber, or the first injection. When the port opens to the first compression chamber, the pressure difference between the intermediate pressure in the first injection port and the internal pressure of the first compression chamber is the time when the second injection port opens to the second compression chamber. Between the intermediate pressure in the second injection port and the internal pressure of the second compression chamber Scroll compressor according to any one of claims 1 to 6, wherein greater than the force difference.