GB2579937A

GB2579937A - Hermetic compressor and refrigeration cycle device

Info

Publication number: GB2579937A
Application number: GB2002843.7A
Authority: GB
Inventors: Hirayama Takuya; Kimura Shigeki
Original assignee: Toshiba Carrier Corp
Current assignee: Toshiba Carrier Corp
Priority date: 2017-09-06
Filing date: 2017-09-06
Publication date: 2020-07-08
Anticipated expiration: 2037-09-06
Also published as: DE112017007976B4; JPWO2019049226A1; GB2579937B; GB202002843D0; JP6886522B2; CN111065826A; WO2019049226A1; CN111065826B; DE112017007976T5

Abstract

[Problem] To provide a low-cost, high-quality compressor for which the degree of design freedom with respect to a connection position between an introduction path and an injection path of an injection flow path can be increased, manufacturing can be optimized, and the opening/closing of a check valve in the injection flow path can be carried out with good precision. [Solution] An injection flow path configured from: an injection path that is provided in a closure member and one end of which opens into a cylinder chamber, the other end opening at a side away from the cylinder chamber; a communication path that is formed between the closure member and an end plate stacked on the closure member in the axial direction of a rotary shaft, and that communicates with the injection path; an introduction path that is provided either on the closure member or the end plate and one end of which opens into the communication path from the axial direction, an injection introduction pipe communicating with the exterior of a sealed case being connected to the other end; and a check valve for opening/closing the opening of the introduction path on the communication-path side, and preventing a flow of refrigerant from the cylinder chamber to the introduction path.

Description

DESCRIPTION

HERMETIC COMPRESSOR AND REFRIGERATION CYCLE APPARATUS

FIELD

[0001] Embodiments according to the present invention relate to a hermetic compressor provided with an injection flow path and a refrigeration cycle apparatus.

BACKGROUND

[0002] For the purpose of cooling, a conventional hermetic compressor is provided with an injection flow path that leads a liquid refrigerant of intermediate pressure inside a refrigeration cycle to a cylinder chamber of a compression mechanism in some cases. This liquid refrigerant of intermediate pressure evaporates in the cylinder chamber and lowers the temperature of the refrigerant to be discharged from the cylinder chamber.

[0003] In some cases, such a hermetic compressor is provided with a check valve in the middle of the injection flow path in order to reduce compression loss caused by backflow of the compressed refrigerant from the cylinder chamber to the injection flow path.

Prior Art Document

Patent Document [0004] Patent Document 1: Japanese Utility Model Application Publication No. S62-173585 Patent Document 2: JP 5760836 B2

Description of Invention

Problems to be solved by Invention [0005] The injection flow path of the compressor disclosed in each of Patent Document 1 and Patent Document 2 includes: an introduction path for introducing the liquid refrigerant into the compression mechanism; and an injection path for injecting the liquid refrigerant having been led through the introduction path into the cylinder chamber. The injection path is formed in the axial direction of a rotating shaft of the compressor, and the introduction path is formed in the radial direction of the rotating shaft of the compressor. In this case, in order to spatially connect the introduction path to the injection path, the design freedom of position connecting the introduction path and the injection path is limited.

[0006] The compressor disclosed in Patent Document 1 includes: a communication pipe connected from a gas injection pipe; and a gas injection flow path for injecting a refrigerant into the cylinder chamber. Since the check valve is provided in a direction perpendicular to the flow direction of the communication pipe, a slight gap is formed between the communication pipe and the check valve, the compressed refrigerant flows backward, and thereby compression loss occurs. In the compressor disclosed in Patent Document 2, it is necessary to accurately insert a slide valve in the middle of the injection introduction path, and thus its productivity is extremely poor.

[0007] An object of the present invention is to provide a compressor that is improved in manufacturability due to high degree of freedom in designing the position connecting the injection path and the introduction path of the injection flow path, and has high compression efficiency by preventing backflow of refrigerant from the check valve in the injection flow path.

Means for solving Problem [0008] To achieve the above object, an aspect of an embodiment of the present invention provides a hermetic compressor including: an electric motor and a compression mechanism that are accommodated in a hermetic housing. The compression mechanism is driven by the electric motor via a rotating shaft having an eccentric portion, and comprises: at least one cylinder having a cylinder chamber; a closure member fixed to one end face of the at least one cylinder, and the closure member closing the cylinder chamber; an end plate stacked on the closure member; a roller configured to eccentrically rotate in the cylinder chamber and compress a refrigerant that has flowed into the cylinder chamber; and an injection flow path that supplies the refrigerant into the cylinder chamber. The injection flow path comprises: an injection path that is provided in the closure member and has one end opened to the cylinder chamber and another end opened to a side of the end plate; a communication path that is formed between the closure member and the end plate, and communicates with the injection path; an introduction path that is provided on either the closure member or the end plate and has one end opened to the communication path in an axial direction of the rotating shaft, and another end connected to an injection introduction pipe communicating with an outside of the hermetic housing; and a check valve that opens and closes an opening of the introduction path on a side of the communication path, and prevents flow of the refrigerant from the cylinder chamber to the introduction path.

Effect of Invention [0009] The injection flow path is composed of an injection introduction pipe, an introduction path, a communication path, and an injection path that are provided on the closure member and the end plate. The introduction path and the injection path are connected by the communication path, which enhances the degree of freedom in designing the position connecting the introduction path and the injection path. The check valve is provided so as to open and close the opening of the introduction path on the side of the communication path located between the closure member and the end plate, and thus backflow can be reliably prevented and the flow path loss can be reduced.

Brief Description of Drawings

[0010] Fig. 1 is a longitudinal cross-sectional view of a hermetic compressor according to a first embodiment and a refrigeration cycle configuration diagram of a refrigeration 20 cycle apparatus.

Fig. 2 is a transverse cross-sectional view of a compression mechanism according to the first embodiment.

Fig. 3 is a longitudinal cross-sectional view of an injection flow path when a check valve is closed in the first embodiment.

Fig. 4 is a longitudinal cross-sectional view of the injection flow path when the check valve is open in the first embodiment.

Fig. 5 is a longitudinal cross-sectional view of a hermetic compressor according to a second embodiment and a refrigeration cycle configuration diagram of a refrigeration cycle apparatus.

Fig. 6 is a longitudinal cross-sectional view of an injection flow path when a check valve is closed in the second embodiment.

Fig. 7 is a plan view of the check valve as viewed in the direction of the arrow in the cross-section taken along the line C-C of Fig. 6.

Fig. 8 is a longitudinal cross-sectional view of the injection flow path when the check valve is open in the 15 second embodiment.

Fig. 9 is a plan view of the check valve as viewed in the direction of the arrow in the cross-section taken along the line C-C of Fig. 8.

DETAILED DESCRIPTION

[0011] Hereinafter, embodiments of the invention will be described.

(First embodiment) A hermetic compressor according to a first embodiment will be described by referring to Fig. 1 to Fig. 4. Fig. 1 is a longitudinal cross-sectional view of the hermetic compressor and a refrigeration cycle configuration diagram of a refrigeration cycle apparatus.

First, the refrigeration cycle 1 will be described. In the refrigeration cycle 1, a hermetic compressor 2 (hereinafter referred to as a compressor), a condenser 3 as a radiator, an expansion device 4, an evaporator 5 as a heat absorber, and an accumulator 6 attached to the compressor 2 are sequentially connected using refrigeration piping. The compressor 2 compresses a gas refrigerant, and the condenser 3 condenses the gas refrigerant to be discharged from the compressor 2 into a liquid refrigerant. The expansion device 4 is a decompressor that decompresses the refrigerant. The evaporator 5 evaporates the liquid refrigerant into the gas refrigerant. The accumulator 6 separates the gas refrigerant and the liquid refrigerant, and supplies the gas refrigerant to the compressor 2. The refrigeration cycle 1 of the first embodiment includes an injection pipe 7 that leads the liquid refrigerant having passed through the condenser 3 to the compressor 2, and the injection pipe 7 communicates with an injection flow path 40 provided with the compressor 2.

[0012] The compressor 2 includes: a hermetic housing 10; an electric motor 14 provided in the upper side of the hermetic housing 10; and a compression mechanism 17 provided in the lower side of the hermetic housing 10. The electric motor 14 includes a stator 15 fixed inside the hermetic housing 10, and a rotor 16 fixed to a rotating shaft 12. The rotating shaft 12 is provided with an eccentric portion 13 on the opposite side of the electric motor 14, and a compression mechanism 17 is provided at the position corresponding to the eccentric portion 13. Thus, the electric motor 14 and the compression mechanism 17 are connected to each other via the rotating shaft 12.

[0013] The compression mechanism 17 includes a cylinder 18 fixed to the hermetic housing 10. A cylinder chamber 19 is formed inside the cylinder 18. A main bearing 25 and an auxiliary bearing 26 as a closure member are disposed above and below the cylinder 18. A muffler 27 is attached to a flange 25f of the main bearing 25, and the muffler 27 forms a muffler chamber 28 with a hollow case surrounding the periphery.

[0014] The eccentric portion 13 of the rotating shaft 12 is located in the cylinder chamber 19, and a roller 22 is rotatably interdigitated with the eccentric portion 13. The roller 22 is disposed so as to eccentrically rotate while bringing the outer peripheral wall into line contact with the inner peripheral face of the cylinder 18 through an oil film during rotation of the rotating shaft 12. A blade groove 24 is formed in the cylinder 18. A blade 23 is accommodated in the blade groove 24, and the blade 23 is to be pressed in the direction of bringing its end into contact with the outer peripheral wall of the roller 22 as shown in Fig. 2 while reciprocating. The blade 23 partitions the cylinder chamber 19 into two spaces 19a and 19b.

[0015] A suction port 20 that leads the gas refrigerant to be supplied from the accumulator 6 to the cylinder chamber 19 is formed in the cylinder 18. Of the spaces partitioned by the blade 23, the one where a space partitioned by the blade 23 and in which the suction port 20 is located is called a suction chamber 19a, and the other space is called a compression chamber 19b. That is, as shown in Fig. 2, the roller 22 rotates counterclockwise in the plane direction.

In this case, the suction port 20 is provided on the left side of the blade 23, the left side of the cylinder chamber 19 is the suction chamber 19a, and the right side of the cylinder chamber 19 is the compression chamber 19b.

[0016] The main bearing 25 is provided with a discharge port (not shown) and a discharge valve for opening and closing the discharge port. When the refrigerant in the cylinder chamber 19 is compressed and the pressure rises, the discharge valve is opened and then the refrigerant in the cylinder chamber 19 is discharged to the muffler chamber 28 through the discharge port. Further, the refrigerant is discharged from the muffler chamber 28 into the hermetic housing 10, and the compressed refrigerant discharged into the hermetic housing 10 is discharged to the outside of the compressor 2 through a discharge pipe 11.

[0017] Next, the injection pipe 7 and the injection flow path 40 will be described. As described above, the injection pipe 7 of the first embodiment leads the liquid refrigerant condensed by the condenser 4 of the refrigeration cycle 1 to the compressor 2. The liquid refrigerant having passed through the injection pipe 7 flows into the injection flow path 40 and is injected into the cylinder chamber 19.

[0018] As shown in Fig. 1 and Fig. 4, the injection flow path 15 40 includes: an injection path 41; a communication path 42; an introduction path 49; an injection introduction pipe 70; and a check valve 44 provided in the communication path 42. The respective flow paths 41, 42, and 49 are provided in the auxiliary bearing 26 that closes the lower side of the cylinder chamber 19 and an end plate 30 that is fixed by a fastening bolt 31 and is stacked on the lower side of a flange 26f of the auxiliary bearing 26. In addition, the injection pipe 7 is provided with an adjusting valve 8 for reducing the pressure of the refrigerant to be led from the downstream side of the condenser 4 and adjusting the injection flow rate.

[0019] The injection path 41 is provided in the auxiliary bearing 26, and includes: a first opening 51 that opens to the cylinder chamber 19; and a second opening 52 that opens to the side of the end plate 30. As shown in Fig. 2, the first opening 51 injects the liquid refrigerant of intermediate pressure into the cylinder chamber 19, and is provided at a position where is opened and closed by the lower face of the roller 22 provided in the cylinder chamber 19.

[0020] The communication path 42 is formed by the end plate 30 and the auxiliary bearing 26. A groove 43 is provided on the upper end face of the end plate 30, the end plate 30 and the auxiliary bearing 26 are stacked, and thereby the groove 43 becomes the communication path 42. The communication path 42 communicates with the injection path 41 through the second opening 52 of the injection path 41.

[0021] The introduction path 49 is provided horizontally in the radial direction of the auxiliary bearing 26, and includes a third opening 53, which axially opens to the communication path 42, on one end side. The other end 54 of the introduction path 49 opens to the outer peripheral surface of the auxiliary bearing 26. The injection introduction pipe 70 communicating with the outside of the hermetic housing 10 is connected to the other end 54 of the introduction path 49, and the injection pipe 7 is connected to the injection introduction pipe 70 outside the hermetic housing 10. A cross-sectional area of the third opening 53 of the introduction path 49 is formed larger than a cross-sectional area of the first opening 51 of the injection path 41.

[0022] The check valve 44 opens and closes the third opening 53 of the introduction path 49 from the side of the communication path 42. The check valve 44 of the first embodiment is a disc-shaped free valve and is energized by a spring 46. A valve seat face 45a being in contact with the auxiliary bearing 26 of the check valve 44 is located on the same plane as the coupling surface between the auxiliary bearing 26 and the end plate 30. The check valve 44 is pressed by the spring 46 in the direction of closing the third opening 53. Fig. 3 shows the injection flow path 40 when the check valve 44 closes the third opening 53 of the introduction path 49, and Fig. 4 shows the injection_ flow path 40 when the check valve 44 opens the third opening 53. [0023] The check valve 44 opens and closes the third opening 53 of the introduction path 49 by the differential pressure 25 between the introduction path 49 and the communication path 42. The communication path 42 communicates with the cylinder chamber 19 via the injection path 41. In other words, when the pressure in the compression chamber 19b is larger than the pressure in the introduction path 49, the check valve 44 closes the third opening 53 of the introduction path 49.

When the pressure in the compression chamber 19b is smaller than the pressure in the introduction path 49, the check valve 44 is pushed out by the refrigerant pressure on the side of the introduction path 49 and opens the third opening 53 of the introduction path 49.

[0024] In such a configuration, the rotor 16 is rotated by energizing the electric motor 14 of the compressor 2. Along with this rotation, the compression mechanism 17 is driven through the rotating shaft 12. When the compression mechanism 17 is driven, the gas refrigerant separated by the accumulator 6 is sucked into the suction chamber 19a of the cylinder chamber 19. The rotation of the roller 22 in the cylinder chamber 19 opens the first opening 51 of the injection path 41 to be formed in the cylinder 18 at the same time as the roller 22 passes the position of the suction port 20. The gas refrigerant sucked from the suction port 20 is compressed by the rotation of the roller 22. Along with this, the liquid refrigerant of intermediate pressure is injected into the compression chamber 19b from the first opening 51 of the injection path 41 to be opened and closed by the rotation of the roller 22, then evaporates in the compression chamber 19b so as to cool the refrigerant in the compression chamber 19b, and then is discharged from the discharge port together with the refrigerant sucked from the suction port 20. The refrigerant discharged from the discharge port is discharged to the exterior of the compressor 2 through the muffler chamber 28, the refrigerant condensed in the condenser 3 is led to the compressor 2 through the branched injection pipe 7.

[0025] The liquid refrigerant having been led from the injection pipe 7 first flows into the introduction path 49 through the injection introduction pipe 70 of the injection flow path 40 in the compressor 2. Next, though it flows toward the third opening 53 of the introduction path 49, the third opening 53 of the introduction path 49 is normally closed by the check valve 44. When the pressure in the introduction path 49 becomes larger than the pressure in the cylinder chamber 19, the check valve 44 is pressed toward the communication path 42 so as to open the third opening 53 of the introduction path 49 and thereby the liquid refrigerant flows into the communication path 42. When the pressure in the introduction path 49 becomes smaller than the pressure in the cylinder chamber 19 again, the check valve 44 closes the third opening 53.

[0026] The liquid refrigerant having flowed into the communication path 42 flows into the injection path 41 through the second opening 52 of the injection path 41. As described above, when the first opening 51 of the injection path 41 to be opened and closed by the lower face of the roller 22 rotating inside the cylinder chamber 19 is opened, the liquid refrigerant having flowed into the injection path 41 is injected into the cylinder chamber 19.

[0027] The injection flow path 40 of the first embodiment is 10 configured such that the injection path 41 and the induction path 49 are provided in the auxiliary bearing 26 and the communication path 42 is provided in the end plate 30. However, it is sufficient that the communication path 42 is formed by coupling the auxiliary bearing 26 and the end plate 30, the third opening 53 of the introduction path 49 is opened in the axial direction, and the valve seat face 45a of the check valve 44 provided in the communication path 42 is located on the same plane as the coupling surface between the auxiliary bearing 26 and the end plate 30. For example, the communication path 42 is formed by providing the groove 43 in the flange 26f of the auxiliary bearing 26 and fixing the end plate 30. In this case, when the introduction path 49 is formed in the end plate 30, the third opening 53 opens in the axial direction and the valve seat 45 of the check valve 44 can be opened and closed from the upper side of the third opening 53 at the same plane as the coupling surface with the auxiliary bearing 26 of the end plate 30.

[0028] According to the compressor 2 of the first embodiment, the injection flow path 40 is composed of the injection introduction pipe 70, the introduction path 49, the communication path 42, and the injection path 41. These flow paths are provided in the auxiliary bearing 26 and the end plate 30, and further, the introduction path 49 and the injection path 41 are spatially connected through the communication path 42. Consequently, the degree of freedom in designing the position connecting the introduction path 49 and the injection path 41 can be enhanced.

[0029] As to the introduction path 49 and the injection path 41, the cross-sectional area of the third opening 53 of the introduction path 49 is formed larger than the cross-sectional area of the first opening 51 of the injection path 41. The flow rate of the liquid refrigerant on the side of the introduction path 49 is increased, and thereby the liquid refrigerant is more readily injected into the cylinder chamber 19. Since the flow path resistance due to the check valve 44 of the liquid refrigerant is reduced by increasing the cross-section of the third opening 53 of the introduction path 49, the flow path loss can be reduced. Consequently, the cooling capacity is enhanced and the compressor becomes highly reliable.

Since the check valve 44 for preventing the backflow of the compressed refrigerant from the cylinder chamber 19 is axially provided in the communication path 42 so as to open and close the third opening 53 of the introduction path 49, the backflow can be reliably prevented and the flow path loss can be reduced.

[0030] Although the end plate 30 is fixed to the auxiliary bearing 26 so as to form the communication path 42, the 10 coupling surface is required to be sealed, so the surface roughness is small and it is formed with high precision. When the valve seat face 45a of the check valve 44 is provided on this coupling surface, the sealing performance can be improved. Since the auxiliary bearing 26 and the end plate 30 are fixed to respective determined positions, the check valve 44 can be prevented from being displacec from the opening and closing surface by providing the end plate 30 with the spring 46 that restricts the movement of the check valve 44.

[0031] The check valve 44 is pressed and energized by the spring 46 in the direction in which the third opening 53 of the introduction path 49 is closed. The backflow from the cylinder chamber 19 to the introduction path 49 can be reliably prevented by the spring 46. Further, a guide (not shown) may be provided on the valve seat face. This guide can prevent the check valve 44 from being displaced from the third opening of the introduction path.

[0032] (Second embodiment) The compressor 2 according to a second embodiment will be described by referring to Fig. 5 to Fig. 9. The same reference signs are assigned to the same or equivalent components as the first embodiment, and duplicate description is omitted.

The compressor 2 of the second embodiment includes two cylinders 18A and 18B in the compression mechanism 17, the A-cylinder 18A is positioned on the lower side and the B-cylinder 18B positioned on the upper side. A partition plate 32 is provided between the two cylinders 18A and 18B, partitions the two cylinders 18A and 18B, and closes the cylinder chamber 19A of the A-cylinder 18A and the cylinder chamber 19B of the B-cylinder 18B. The partition plate 32 is formed by stacking two partition plate members 32A and 32B. [0033] In the compressor 2 of the second embodiment, the injection flow path 40 is provided with the partition plate 32. In detail, the partition plate 32 functions as a closure member for closing the cylinder chamber 19B of the B-cylinder 18B and also functions as an end plate for closing the cylinder chamber 19A of the A-cylinder 18A.

[0034] As shown in Fig. 6 and Fig. 8, the injection path 41 for injecting the liquid refrigerant into the cylinder chamber 19B is provided in the partition plate member 32B, and an auxiliary injection path 50 for injecting the liquid refrigerant into the cylinder chamber 19A is provided in the partition plate member 32A. The injection path 41 forms the first opening 51 that opens to the cylinder chamber 19B of the B-cylinder 18B and the second opening 52 that opens to the communication path 42. One end of the auxiliary injection path 50 forms a fifth opening that opens to the cylinder chamber 19A of the A-cylinder 18A, and the other end of the auxiliary injection path 50 opens to the communication path 42. The communication path 42 is formed by stacking the groove 43 provided on the partition plate member 32B and the end face of the partition plate member 32A. The introduction path 49 is provided horizontally in the radial direction on the partition plate member 32A and has the third opening 53 of the introduction path 42 on one end side, the third opening 53 axially opens to the communication path 42, and the other end 54 of the introduction path 49 opens on the outer peripheral surface of the partition plate member 32A. The injection introduction pipe 70 communicating with the outside of the hermetic housing 10 is connected to the other end 54 of the introduction path 49, and the injection pipe 7 is connected to the injection introduction pipe 70 outside the hermetic housing 10.

[0035] In the compressor 2 of the second embodiment, the communication path 42 is formed above the third opening 53 of the introduction path 49. The check valve 44 for opening and closing the third opening 53 of the introduction path 49 is provided on the side of the communication path 42. The check valve 44 of the second embodiment contacts the valve seat 45 by gravity, and closes the third opening 53 of the introduction path 49. When the pressure in the introduction path 49 increases, the check valve 44 is lifted and the third opening 53 in the introduction path 49 opens. Thus, an energizing member such as the spring 46 can be omitted. Also in the case of the second embodiment, a energizing member such as the spring 46 may be provided to ensure the operation of the check valve 44. Further, a guide wall 47 is formed, and this guide wall 47 guides the check valve 44 such that the check valve 44 is not displaced from the position of the third opening 53 of the introduction path 49. A check-valve backpressure portion 48 is provided such that the depth of the guide wall 47 becomes shallower than the depth of the communication path 42 for preventing the check valve 44 from sticking to the upper portion of the guide wall 47.

[0036] In such a configuration, the liquid refrigerant flowing 25 through the injection pipe 7 passes through the injection introduction pipe 70, the introduction path 49, the communication path 42, the injection path 41, and the auxiliary injection path 50 so as to be injected into the respective cylinder chambers 19A and 19B in a manner similar to the first embodiment. In this cace, the check valve 44 opens and closes the third opening 53 of the induction path 49 by the difference between the pressure of the induction path 49 and the total pressure of the cylinders 18A and 16B and gravity.

[0037] Fig. 7 is a plan view of the check valve 44 as viewed in the direction of the arrow in the cross-section taken along the line C-C of Fig. 6. Similarly, Fig. 9 is a plan view of the check valve 44 as viewed in the direction of the arrow in the cross-section taken along the line C-C of Fig. 8. The guide wall 47 is formed on the partition plate member 32B to guide the check valve 44 such that the check valve 44 closes the third opening 53 of the introduction path 49 without slipping. As shown in Fig. 9, the guide wall 47 is formed so as to be slightly larger in diameter than the check valve 44.

[0038] According to the compressor 2 of the second embodiment, even in the case of the rotary compressor having the two cylinders 18A and 18B, the liquid refrigerant can be supplied to the respective cylinder chambers 19A and 19B by forming the injection flow path 40 in the partition plate 32 composed of the two partition plate members 32A and 32B.

[0039] Since the check valve 44 is provided on the third opening 53 of the introduction path 49 which is before the 5 branching portion between the injection path 41 and the auxiliary injection path 50, the backflow of the liquid refrigerant, which has flowed into the injection flow path 40, from the respective cylinder chambers 19A and 19B can be prevented using one check valve 44.

[0040] According to the compressor 2 of at least one embodiment described above, the injection flow path 40 for leading the liquid refrigerant to the cylinder chamber 19 of the compression mechanism 17 is composed of the injection introduction pipe, the introduction path 49, the injection path 41, and the communication path 42 that communicates the introduction path 49 and the injection path 41. Since the communication path 42 is formed by coupling two members of the closure member 26, 32A and the end plate 30, 32B and the introduction path 49 can be formed on either the closure member 26, 32A or the end plate 30, 32B, the degree of freedom in designing the position connecting the introduction path 49 and the injection path 41 can be enhanced. The check valve 44 provided in the communication path 42 opens and closes the third opening 53 of the induction path 49 that opens in the axial direction of the rotating shaft 12, and the valve seat face 45a is provided on the same plane as the end plate 30, 32 and the closure member 26, 32A formed with high precision and small surface roughness. Thus, the sealing performance of the valve seat face 45a can be enhanced. Consequently, the backflow of the refrigerant from the check valve 44 can be prevented.

[0041] Further, the check valve 44 can be opened and closed with high accuracy by adopting a configuration in which the check valve 44 of the first embodiment is provided with the spring 46 or by adopting a configuration in which the guide wall 47 of the second embodiment is provided. Although a description has been given of the check valve 44 configured as a free valve in the above-described embodiments, the check valve 44 may be configured as a reed valve.

[0042] As to the introduction path 49 and the injection path 41, the cross-sectional area of the third opening 53 of the introduction path 49 is formed larger than the cross-sectional area of the first opening 51 of the injection path 41. In this manner, the flow rate on the side of the introduction path 49 is increased, and thereby the refrigerant flowing through the injection flow path 40 is more readily injected into the cylinder chamber 19. Further, the flow path resistance due to the check valve 44 of the liquid refrigerant is reduced by increasing the cross-section of the third opening 53 of the introduction path 49, and thus the flow path loss can be reduced. Since the above-described configuration is adopted, a highly reliable compressor 2 with enhanced cooling capacity can be provided.

[0043] The compressor 2 of the embodiment can be applied to a case where a plurality of cylinders 19 are provided, and has a configuration in which two partition plate members 32A and 32B are stacking in the axial direction and the injection flow path 40 is provided for each. The backflow from the plurality of cylinder chambers 19 can be prevented by one check valve 44 by adopting such a configuration, and thus the compressor 2 is highly manufacturable due to simplification of its configuration and can be manufactured at low cost.

[0044] Although the compressor 2 of the embodiment is a rotary compressor with the use of the blade 23 and the roller 22, the same effect can be obtained when the injection flow path 40 of the embodiment is formed in a swing-type compressor in which the blade 23 and the rotor 22 are integrated.

[0045] While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions.

Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.

Reference Signs List [0046] 1 refrigeration cycle apparatus 2 compressor 3 condenser 4 expansion device evaporator 6 accumulator 7 injection pipe hermetic housing 12 rotating shaft 14 electric motor 17 compression mechanism 18 cylinder 19 cylinder chamber 22 roller 23 blade 25 main bearing 26 auxiliary bearing end plate 32 partition plate 32A, 32B partition plate member injection flow path 41 injection path 42 communication path 44 check valve 47 guide wall

49 introduction path

50 auxiliary injection path 51 first opening 52 second opening 53 third opening

54 other end of the introduction path

Claims

Claims 1. A hermetic compressor comprising: an electric motor and a compression mechanism that are 5 accommodated in a hermetic housing, wherein the compression mechanism is driven by the electric motor via a rotating shaft having an eccentric portion, and comprises: at least one cylinder having a cylinder chamber; a closure member fixed to one end face of the at least one cylinder, and the closure member closing the cylinder chamber; an end plate stacked on the closure member; a roller configured to eccentrically rotate in 15 the cylinder chamber and compress a refrigerant that has flowed into the cylinder chamber; and an injection flow path that supplies the refrigerant into the cylinder chamber, and wherein the injection flow path comprises: an injection path that is provided in the closure member and has one end opened to the cylinder chamber and another end opened to a side of the end plate; a communication path that is formed between the closure member and the end plate, and communicates with the 25 injection path;an introduction path that is provided on eitherthe closure member or the end plate and has one end opened to the communication path in an axial direction of the rotating shaft, and another end connected to an injection introduction pipe communicating with an outside of the hermetic housing; and a check valve that opens and closes an opening of the introduction path on a side of the communication path, and prevents flow of the refrigerant from the cylinder chamber to the introduction path.
2. The hermetic compressor according to claim 1, wherein a cross-sectional area of the opening of the introduction path on the side of the communication path is formed larger than a cross-sectional area of an opening of the injection path on a side of the cylinder chamber.
The hermetic compressor according to claim 1, wherein a valve seat face of the check valve is located at a same plane as a coupling surface between the closure member and the end 20 plate.
4. The hermetic compressor according to claim 1, wherein the check valve opens and closes the opening of the introduction path by moving in the axial direction.
J. The hermetic compressor according to claim 1, wherein the check valve is pressed by an energizing member in a direction of closing the opening of the introduction path.
6. The hermetic compressor according to claim 1, further 5 comprising a guide wall formed in the communication path, wherein: the check valve is disk-shaped; and the guide wall guides the check valve in such a manner that the check valve is not displaced from a position of the 10 opening of the introduction path when closing the opening of the introduction path.
7. The hermetic compressor according to any one of claim 1 to claim 6, wherein: the at least one cylinder comprises a plurality of cylinders; the closure member, the end plate, and the injection flow path are provided between the plurality of cylinders in such a manner that the closure member closes the cylinder chamber of one of the plurality of cylinders and the end plate closes the cylinder chamber of another of the plurality of cylinders.
8. The hermetic compressor according to claim 7, wherein 25 the end plate is provided with an auxiliary injection path that has one end opened to the cylinder chamber of the another of the plurality of cylinders and another end opened to the communication path.
9. A refrigeration cycle apparatus comprising: the hermetic compressor according to any one of claim 1 to claim 8; a radiator connected to the hermetic compressor; an expansion device connected to the radiator; and a heat absorber connected between the expansion device and the hermetic compressor.