Rotary compressor and apparatus

Abstract

A rotary compressor (1) includes a compression mechanism (30) having a cylinder (31), a piston (32) disposed in the cylinder (31), and vanes (33) partitioning the inside of the cylinder (31), a shaft (40) having an eccentric portion (42) disposed in the cylinder (31), a vane groove (36) in which the vanes (33) are disposed, the eccentric portion (42) engaging with the piston (32), and the vanes (33) operating without leaving the piston (32). By bringing the refrigerator oil and the working fluid into a two-phase separated state under a temperature condition of 25 DEG C, lubrication performance can be ensured and a good sliding state can be maintained even if liquid compression operation cannot be avoided.

Description

Technical Field

[0001] The present invention relates to a rotary compressor in which a vane moves without leaving a piston, and an apparatus using the rotary compressor. Background Art

[0002] Patent Document 1 discloses a rotary compressor in which a cylindrical groove is formed in a piston and a cylindrical portion configured in the cylindrical groove is formed at an end of a vane, so that the vane moves without leaving the piston.

[0003] Patent Document 2 discloses a rocking type rotary compressor that uses an immiscible oil having a region where the oil component ratio is immiscible in the range of -40°C to 31°C.

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Patent Laid-Open No. 3-185291

[0007] Patent Document 2: Japanese Patent Laid-Open No. 2008-101523 Summary of the Invention

[0008] Problems to be Solved by the Invention

[0009] When a liquid refrigerant is inhaled and compressed, the closed container is filled with the liquid refrigerant, and the viscosity of the refrigerating oil is lowered by dissolving a large amount of the liquid refrigerant in the refrigerating oil.

[0010] In the rotary compressor described in Patent Document 1, since the piston and the vane do not separate, when the liquid refrigerant is inhaled into the compression chamber, liquid compression is performed. Compared with gas compression, liquid compression imposes a greater load on the compressor.

[0011] Thus, since the decrease in the viscosity of the refrigerating oil and the increase in the load due to liquid compression occur simultaneously, the sliding state of the compressor deteriorates.

[0012] In addition, if the immiscible oil as described in Patent Document 2 is discharged from the compressor, it is difficult to return to the compressor, and a shortage of the refrigerating oil in the compressor is likely to occur.

[0013] Therefore, an object of the present invention is to provide a rotary compressor and an apparatus using the rotary compressor that can ensure lubricating performance and maintain a good sliding state even when liquid compression operation cannot be avoided.

[0014] Means for Solving the Problems

[0015] According to a first aspect of the present invention, there is provided a rotary compressor 1 having a motor section 20 and a compression mechanism section 30 within a hermetic container 10. An oil storage section 11 for storing refrigerating oil is formed at the bottom within the hermetic container 10. An intake pipe 12 for guiding a working fluid to the compression mechanism section 30 and a discharge pipe 13 for guiding the working fluid compressed by the compression mechanism section 30 outside the hermetic container 10 are provided within the hermetic container 10. After the working fluid compressed by the compression mechanism section 30 is discharged into the hermetic container 10, it is guided from the discharge pipe 13 outside the hermetic container 10. The motor section 20 and the compression mechanism section 30 are connected by a shaft 40. The compression mechanism section 30 has a cylinder 31, a piston 32 disposed within the cylinder 31, and a vane 33 for partitioning the interior of the cylinder 31. The shaft 40 has an eccentric portion 42. A vane groove 36 for disposing the vane 33 is formed in the cylinder 31. The eccentric portion 42 is disposed within the cylinder 31. The piston 32 is fitted with the eccentric portion 42. The vane 33 operates without separating from the piston 32. The rotary compressor 1 is characterized in that at a temperature condition of 25°C, the refrigerating oil and the working fluid are in a two-phase separation state.

[0016] Based on the first aspect, a rotary compressor 1 according to a second aspect of the present invention is characterized in that a cylindrical groove 32a with an arc angle α exceeding 180° is formed in the piston 32, and a cylindrical portion 33b disposed within the cylindrical groove 32a is formed at an end of the vane 33.

[0017] Based on the first aspect, a rotary compressor 1 according to a third aspect of the present invention is characterized in that at a temperature condition of 0°C to 25°C, in a mixture in which the working fluid is maximally dissolved in the refrigerating oil, the proportion of the working fluid is less than 30 wt%.

[0018] Based on the first aspect, a rotary compressor 1 according to a fourth aspect of the present invention is characterized in that an accumulator 14 is not provided upstream of the intake pipe 12.

[0019] Based on the first aspect, a rotary compressor 1 according to a fifth aspect of the present invention is characterized in that an accumulator 14 is provided upstream of the intake pipe 12, and the volume of the liquid storage section 14f of the accumulator 14 is set to be 2 times or less the intake volume formed within the cylinder 31.

[0020] Based on any one of the first to fifth aspects, a rotary compressor 1 according to a sixth aspect of the present invention is characterized in that the working fluid is set as R32 and the refrigerating oil is set as alkylbenzene oil.

[0021] Based on any one of the first to fifth aspects, the rotary compressor 1 according to the seventh aspect of the present invention is characterized in that the working fluid is set as carbon dioxide, and the refrigeration oil is set as polyalkylene glycol oil.

[0022] Based on any one of the first to fifth aspects, the rotary compressor 1 according to the eighth aspect of the present invention is characterized in that the working fluid is set as R290, and the refrigeration oil is set as polyalkylene glycol oil.

[0023] The present invention provides a ninth aspect of an apparatus that uses the rotary compressor 1 according to any one of the first to fifth aspects, characterized in that the rotary compressor 1, the condenser 2, the decompression device 3, and the evaporator 4 are connected in a loop through piping.

[0024] Advantages of the Invention

[0025] According to the present invention, in particular, even in a case where liquid compression operation cannot be avoided by using a refrigeration oil having low compatibility with the working fluid in the low rotation region, lubrication performance can be ensured, and a good sliding state can be maintained. Description of the Drawings

[0026] Figure 1 It is a cross-sectional view showing a rotary compressor according to an embodiment of the present invention.

[0027] Figure 2 is Figure 1 A sectional view taken along line A-A shown.

[0028] Figure 3 It is a view showing a piston and a vane for a rotary compressor according to the same embodiment.

[0029] Figure 4 It is a view showing a manufacturing process of a vane for a rotary compressor according to the same embodiment.

[0030] Description of Reference Numerals

[0031] 1 Rotary compressor

[0032] 2 Condenser

[0033] 3 Decompression device

[0034] 4 Evaporator

[0035] 10 Hermetic container

[0036] 11 Oil storage part

[0037] 12 Suction pipe

[0038] 13 Discharge pipe

[0039] 14 Accumulator

[0040] 14a Outer cylinder

[0041] 14b Refrigerant suction pipe

[0042] 14c Separation plate

[0043] 14d Outer cylinder inlet

[0044] 14e Suction pipe inlet

[0045] 14f Liquid storage part

[0046] 20 Motor part

[0047] 21 Stator

[0048] 22 Rotor

[0049] 30 Compression mechanism part

[0050] 31 Cylinder

[0051] 32 Piston

[0052] 32a Cylindrical groove

[0053] 33 Vane

[0054] 33a Vane side surface part

[0055] 33b Cylindrical part

[0056] 33c Narrowing part

[0057] 33d Notch part

[0058] 33e Arc surface

[0059] 33e1 Suction side arc surface

[0060] 33e2 Discharge side arc surface

[0061] 34 Compression chamber

[0062] 34a Suction space

[0063] 34b Compression space

[0064] 35 Suction passage

[0065] 36 Vane groove

[0066] 37 Discharge hole

[0067] 40 Shaft

[0068] 41 Main shaft part

[0069] 42 Eccentric part

[0070] 43 Countershaft part

[0071] 46 Oil supply passage inside the shaft

[0072] 47 Connecting passage

[0073] 51 Upper bearing

[0074] 52 Lower bearing

[0075] 53 Upper cover

[0076] 54 Soundproof chamber

[0077] H Height

[0078] M Connecting surface

[0079] X Extended imaginary surface

[0080] Y Fixture

[0081] Z Cutting tool

[0082] α, β, γ Arc angles Detailed implementation manners

[0083] In the rotary compressor according to the first embodiment of the present invention, at a temperature condition of 25°C, the refrigeration oil and the working fluid are in a two-phase separation state. According to this embodiment, in particular, even when it is impossible to avoid liquid compression operation by using a refrigeration oil with low compatibility with the working fluid in the low rotation region, lubrication performance can be ensured and a good sliding state can be maintained.

[0084] Based on the rotary compressor of the first embodiment of the present invention, in the second embodiment of the present invention, a cylindrical groove with an arc angle exceeding 180° is formed on the piston, and a cylindrical portion configured in the cylindrical groove is formed at the end of the vane. According to this embodiment, due to the surface contact formed by the cylindrical portion and the cylindrical groove, the wear resistance is high.

[0085] Based on the rotary compressor of the first embodiment of the present invention, in the third embodiment of the present invention, at a temperature condition of 0°C to 25°C, in the mixture in which the working fluid is maximally dissolved in the refrigeration oil, the proportion of the working fluid is less than 30 wt%. According to this embodiment, in particular, even when it is impossible to avoid liquid compression operation by using a refrigeration oil with low compatibility with the working fluid in the low rotation region, lubrication performance can be ensured and a good sliding state can be maintained.

[0086] Based on the rotary compressor of the first embodiment, the fourth embodiment of the present invention does not have an accumulator upstream of the suction pipe. According to this embodiment, even in the case where liquid compression operation cannot be avoided, lubrication performance can be ensured and a good sliding state can be maintained, so the accumulator may not be provided.

[0087] Based on the rotary compressor of the first embodiment, the fifth embodiment of the present invention has an accumulator upstream of the suction pipe, and the volume of the liquid storage part of the accumulator is set to be 2 times or less of the suction volume formed in the cylinder. According to this embodiment, even in the case where liquid compression operation cannot be avoided, lubrication performance can be ensured and a good sliding state can be maintained, so the accumulator can be made smaller.

[0088] Based on the rotary compressors of the first to fifth embodiments, the sixth embodiment of the present invention uses R32 as the working fluid and alkylbenzene oil as the refrigeration oil. According to this embodiment, the compatibility is low, lubrication performance can be ensured, and a good sliding state can be maintained.

[0089] Based on the rotary compressors of the first to fifth embodiments, the seventh embodiment of the present invention uses carbon dioxide as the working fluid and polyalkylene glycol oil as the refrigeration oil. According to this embodiment, the compatibility is low, lubrication performance can be ensured, and a good sliding state can be maintained.

[0090] Based on the rotary compressors of the first to fifth embodiments, the eighth embodiment of the present invention uses R290 as the working fluid and polyalkylene glycol oil as the refrigeration oil. According to this embodiment, the compatibility is low, lubrication performance can be ensured, and a good sliding state can be maintained.

[0091] The ninth embodiment of the present invention provides a device that uses the rotary compressor of the first to fifth embodiments. Among them, the rotary compressor, condenser, decompression device, and evaporator are connected in a ring through pipes. According to this embodiment, a device with high reliability can be provided.

[0092]

Embodiment

[0093] Figure 1 It is a cross-sectional view of a rotary compressor showing an embodiment of the present invention. Figure 2 is Figure 1 a view in the direction of line A-A shown in

[0094] The rotary compressor 1 of this embodiment includes a motor part 20 and a compression mechanism part 30 in a sealed container 10. The motor part 20 and the compression mechanism part 30 are connected by a shaft 40.

[0095] The motor unit 20 is composed of a stator 21 fixed to the inner surface of the sealed container 10 and a rotor 22 that rotates within the stator 21.

[0096] The compression mechanism unit 30 includes a cylinder 31, a piston 32 disposed within the cylinder 31, and a vane 33 that divides the interior of the cylinder 31 (refer to Figure 2 ).

[0097] An upper bearing 51 is disposed on one side of the cylinder 31, and a lower bearing 52 is disposed on the other side of the cylinder 31.

[0098] The shaft 40 is composed of a main shaft portion 41 that mounts the rotor 22 and is supported by the upper bearing 51, an eccentric portion 42 for mounting the piston 32, and a sub-shaft portion 43 that is supported by the lower bearing 52.

[0099] The upper bearing 51 is fixed to the sealed container 10. The piston 32 is rotatably fitted to the eccentric portion 42 of the shaft 40 that passes through the interior of the cylinder 31.

[0100] An upper cover 53 is provided above the upper bearing 51. A soundproof chamber 54 is formed between the upper bearing 51 and the upper cover 53. The high-pressure refrigerant gas compressed by the compression mechanism unit 30 is discharged into the soundproof chamber 54. The high-pressure refrigerant gas discharged into the soundproof chamber 54 is discharged into the sealed container 10.

[0101] An oil storage portion 11 is formed at the bottom within the sealed container 10. The oil storage portion 11 stores refrigeration oil. An oil supply passage 46 is formed axially within the shaft 40. A communication passage 47 for supplying refrigeration oil to the sliding surfaces of the compression mechanism unit 30 is formed within the eccentric portion 42.

[0102] The refrigeration oil within the oil storage portion 11 is introduced into the oil supply passage 46 from the lower end of the shaft 40. A part of the refrigeration oil introduced into the oil supply passage 46 is supplied to the sliding surfaces of the compression mechanism unit 30 through the communication passage 47.

[0103] An intake pipe 12 is connected to the side of the sealed container 10, and a discharge pipe 13 is connected to the upper surface of the sealed container 10. The intake pipe 12 guides the refrigerant to the compression mechanism unit 30. The discharge pipe 13 guides the refrigerant compressed by the compression mechanism unit 30 and discharged into the sealed container 10 to the outside of the sealed container 10.

[0104] An accumulator 14 is provided on the upstream side of the intake pipe 12.

[0105] In the rotary compressor 1 of the present embodiment, a condenser 2, a pressure reducing device 3, and an evaporator 4 are connected in a loop by piping. The condenser 2 condenses the refrigerant discharged from the discharge pipe 13. The pressure reducing device 3 reduces the pressure of the refrigerant condensed by the condenser 2. The evaporator 4 evaporates the refrigerant whose pressure has been reduced by the pressure reducing device 3.

[0106] The refrigerant evaporated by the evaporator 4 returns to the accumulator 14.

[0107] The accumulator 14 has an outer cylinder 14a, a refrigerant suction pipe 14b, and a separation plate 14c. An outer cylinder inlet 14d for introducing the refrigerant from the evaporator 4 is provided at the upper part of the outer cylinder 14a. The refrigerant suction pipe 14b has a suction pipe inlet 14e inside the outer cylinder 14a. The separation plate 14c is disposed between the outer cylinder inlet 14d and the suction pipe inlet 14e.

[0108] A liquid storage portion 14f is formed at the inner bottom of the outer cylinder 14a. The liquid refrigerant is stored in the liquid storage portion 14f. The liquid refrigerant can be stored up to the height H of the suction pipe inlet 14e. Therefore, the volume up to the height H of the suction pipe inlet 14e becomes the volume of the liquid storage portion 14f.

[0109] In addition, the specific driving method of the rotary compressor 1 is not particularly limited. For example, the rotary compressor 1 can also be driven by simple on-off control, but it can also be driven in an inverter manner at multiple operating frequencies. In the inverter drive, a low rotation region where the rotational speed of the motor unit 20 decreases or a high rotation region where the rotational speed of the motor unit 20 increases is generated in order to optimize the operation control of the rotary compressor 1.

[0110] Figure 2 The compression chamber 34 shown is formed between the upper bearing 51 and the lower bearing 52 and between the inner peripheral surface of the cylinder 31 and the outer peripheral surface of the piston 32.

[0111] The suction pipe 12 is connected to the suction passage 35 of the compression mechanism portion 30.

[0112] The suction passage 35 communicates with the compression chamber 34.

[0113] By the rotation of the shaft 40, the piston 32 performs a revolution motion.

[0114] The vane 33 reciprocates in the vane groove 36 by the piston 32 that revolves along the inner wall surface of the cylinder 31.

[0115] The compression chamber 34 is divided by the vane 33 into a suction space 34a communicating with the suction passage 35 and a compression space 34b communicating with the discharge hole 37. The suction volume formed in the cylinder 31 is the volume of the suction space 34a in a state where the suction passage 35 is blocked by the piston 32, and is the volume in a state where the suction space 34a becomes the maximum space.

[0116] The gaseous refrigerant sucked into the compression chamber 34 through the suction passage 35 from the suction pipe 12 by the revolution motion of the piston 32 is compressed in the compression chamber 34 and then discharged from the discharge hole 37 into the soundproof chamber 54.

[0117] The refrigerant gas discharged into the soundproof chamber 54 is discharged into the closed container 10 and discharged outside the closed container 10 from the discharge pipe 13. The high-pressure refrigerant gas discharged outside the closed container 10 becomes low-pressure refrigerant gas via the condenser 2, the decompression device 3, and the evaporator 4, and returns to the compression mechanism section 30 via the accumulator 14.

[0118] Figure 3 It is a diagram showing the piston and vane for a rotary compressor of the same embodiment. Figure 3 (a) is a perspective view showing the piston and vane in a separated state. Figure 3 (b) is a top view showing the piston and vane in a separated state. Figure 3 (c) is a perspective view of the vane observed from a different direction.

[0119] A cylindrical groove 32a with an arc angle α exceeding 180° is formed on the outer peripheral surface of the piston 32. The cylindrical groove 32a extends from one end face of the piston 32 to the other end face.

[0120] The vane 33 has a vane side surface portion 33a that slides in the vane groove 36, a cylindrical portion 33b disposed in the cylindrical groove 32a, and a constricted portion 33c that connects the vane side surface portion 33a and the cylindrical portion 33b. The cylindrical portion 33b is formed at the end of the vane 33.

[0121] By engaging the cylindrical portion 33b with the cylindrical groove 32a, the vane 33 operates without separating from the piston 32.

[0122] A notch portion 33d extending from one end face to the other end face is formed on the cylindrical portion 33b. The cylindrical portion 33b divides the arc surface 33e of the cylindrical portion 33b into a plurality of parts through the notch portion 33d. Thus, arc surfaces 33e that are at least separated into two parts are formed on the outer peripheral surface of the cylindrical portion 33b through the notch portion 33d.

[0123] Each arc surface 33e is set to an arc angle β greater than 90° and less than 180°, and the notch portion 33d is set to an arc angle γ less than 45°. In addition, the arc angle β is preferably 110° or more and 150° or less.

[0124] By setting the notch portion 33d to an arc angle γ less than 45°, the contact area between the cylindrical groove 32a and the cylindrical portion 33b can be increased, and refrigerant leakage can be reliably prevented.

[0125] In this embodiment, the notch portion 33d is formed at the front end portion of the blade 33. That is, the notch portion 33d is formed at the front end of the cylindrical portion 33b. It is not easy to apply a load to the front end portion of the blade. By forming the notch portion 33d at the front end portion of the blade, the suction side arc surface 33e1 and the discharge side arc surface 33e2 can be symmetrically formed through the notch portion 33d. In addition, in this embodiment, the notch portion 33d is formed as a flat surface, but as long as the notch portion 33d is cut in a manner that makes it an inner side surface compared to the arc-shaped outer peripheral surface of the cylindrical portion 33b, it may also be formed as a curved surface, or may be formed of a single flat surface.

[0126] Preferably, the two formed arc surfaces 33e are arranged at the position closest to the extended imaginary plane X on the side surface of the blade side surface portion 33a. In this way, since the point on the side surface of the blade side surface portion 33a in the cylindrical portion 33b that is closest to the extended imaginary plane X is located on the arc surface 33e, refrigerant leakage can be reliably prevented.

[0127] The Vickers hardness of the surface of the piston 32 is set to Hv400 or less. Since the piston 32 itself uses a low-hardness member, the cylindrical groove 32a is easily formed. Since the surfaces formed by the cylindrical portion 33b and the cylindrical groove 32a are in contact, the wear resistance is also high.

[0128] The Vickers hardness of the surface of the piston 32 is preferably set in the range of Hv80 to Hv400, and more preferably set in the range of Hv180 to Hv250.

[0129] The piston 32 preferably uses a gray cast iron material. Since the gray cast iron material is used, the cylindrical groove 32a is easily formed. In addition, the piston 32 can be formed of a sintered material. When the piston 32 uses a sintered material, the Vickers hardness is preferably set to Hv400 or less.

[0130] The surface of the blade side surface portion 33a, that is, the side surface of the blade 33, is surface-treated, and the side surface of the blade 33 is set to a hardness with a Vickers hardness exceeding Hv1000. Therefore, sufficient sliding resistance can be achieved with respect to the blade groove 36.

[0131] Nitriding treatment or DLC treatment is suitable for the surface treatment of the blade side surface portion 33a. By performing nitriding treatment or DLC treatment, a hard coating treatment can be performed on the blade side surface portion 33a.

[0132] The surface hardness of at least a part of the cylindrical portion 33b is lower than that of the vane side surface portion 33a. In addition, at least a part of the cylindrical portion 33b refers to the arc surface 33e. The same applies in the following description. Thus, by making the surface hardness of at least a part of the cylindrical portion 33b lower than that of the vane side surface portion 33a, sliding resistance with respect to the vane groove 36 is achieved, and by making the surface hardness of at least a part of the cylindrical portion 33b lower than that of the vane side surface portion 33a, the workability and toughness of the cylindrical portion 33b can be improved.

[0133] The Vickers hardness of at least a part of the cylindrical portion 33b is preferably lower than the Vickers hardness of the vane side surface portion 33a by Hv200 or more. That is, by performing a hard coating treatment on the vane side surface portion 33a to make the Vickers hardness of the vane side surface portion 33a higher than the Vickers hardness of at least a part of the cylindrical portion 33b by Hv200 or more, sufficient sliding resistance with respect to the vane groove 36 can be achieved.

[0134] In addition, the surface hardness of the constricted portion 33c is lower than that of the vane side surface portion 33a. Thus, by making the surface hardness of the constricted portion 33c lower than that of the vane side surface portion 33a, the workability and toughness of the constricted portion 33c can be improved, and by making the surface hardness of the vane side surface portion 33a higher than that of the constricted portion 33c, sliding resistance with respect to the vane groove 36 can be achieved.

[0135] Furthermore, the surface hardness of the constricted portion 33c is preferably lower than that of the cylindrical portion 33b. By making the surface hardness of the constricted portion 33c lower than that of the vane side surface portion 33a or the cylindrical portion 33b, the workability and toughness of the constricted portion 33c can be improved. In addition, the surface hardness of the arc surface 33e is preferably lower than that of the notch portion 33d. By making the surface hardness of the arc surface 33e lower than that of the notch portion 33d, the workability and toughness of the arc surface 33e can be improved.

[0136] Figure 4 It is a diagram showing the manufacturing process of the vane for a rotary compressor of the same embodiment.

[0137] Figure 4 (a) shows the base material of the vane 33. The vane 33 uses a ferroalloy mainly composed of iron (Fe) and containing chromium (Cr), or a steel material obtained by adding metal materials such as chromium (Cr), tungsten (W), vanadium (V), and molybdenum (Mo) to high-carbon steel. In addition, since the vane 33 uses a steel material without adding tungsten (W) and vanadium (V), cost reduction can be achieved. In addition, the vane 33 can use stainless steel (e.g., SUS440C).

[0138] Figure 4 (b) shows Figure 4The state in which the base material of the blade 33 shown in (a) has been subjected to hard film coating treatment.

[0139] As Figure 4 As shown in (c), the base material of the blade 33 that has been subjected to hard film coating treatment is fixed to the jig Y, and the cylindrical portion 33b and the narrowed portion 33c are machined by the cutting tool Z.

[0140] As Figure 4 As shown in (c), in order to form the cylindrical portion 33b with an arc angle α exceeding 180°, finish machining needs to be carried out in two or more times, and the machining accuracy at the connecting surface M of the machining surfaces is reduced.

[0141] However, by dividing the arc surface 33e of the cylindrical portion 33b into a plurality of parts through the notch portion 33d, and setting each arc surface 33e to an arc angle β less than 180°, the machining accuracy of the arc surface 33e of the cylindrical portion 33b can be improved.

[0142] In particular, by forming the notch portion 33d at the connecting surface M, that is, the front end of the cylindrical portion 33b, machining can be carried out only through two finish machinings, namely, the finish machining of the suction side arc surface 33e1 and the finish machining of the discharge side arc surface 33e2.

[0143] The working fluid and the refrigeration oil, which have been described as refrigerants in this embodiment, are in a two-phase separation state at a temperature of 25°C. Thus, in particular, even when it is impossible to avoid liquid compression operation by using a refrigeration oil with low compatibility with the working fluid in the low rotation region of the rotary compressor 1, lubricating performance can be ensured, and a good sliding state can be maintained. Here, the low rotation region refers to a rotation speed region of 900 rpm or less, particularly 600 rpm or less, and further 360 rpm or less. In the low rotation region, liquid compression is likely to occur. By ensuring the lubricating performance in the low rotation region where liquid compression is likely to occur, the operation in the low rotation region, that is, the low-capacity operation, can be carried out stably.

[0144] In addition, in the mixture in which the working fluid is maximally dissolved in the refrigeration oil under the temperature condition of 0°C to 25°C, the proportion of the working fluid is 1 wt% or more and less than 30 wt%. Thus, in particular, even when it is impossible to avoid liquid compression operation by using a refrigeration oil with low compatibility with the working fluid in the low rotation region, lubricating performance can be ensured, and a good sliding state can be maintained.

[0145] In this embodiment, it has been described that the accumulator 14 is included upstream of the suction pipe 12, but the accumulator 14 can be omitted. That is, even when it is not possible to avoid liquid compression operation by using a refrigerating oil with low compatibility with the working fluid, the lubricating performance of the refrigerating oil can be ensured, and a good sliding state can be maintained. Therefore, the accumulator 14 may not be provided either.

[0146] In addition, the volume of the liquid storage portion 14f of the accumulator 14 can be set to be 2 times or less of the suction volume formed in the cylinder 31. That is, even when it is not possible to avoid liquid compression operation by using a refrigerating oil with low compatibility with the working fluid, the lubricating performance can be ensured, and a good sliding state can be maintained. Therefore, the accumulator 14 can be made smaller.

[0147] In addition, in this embodiment, the compression mechanism portion 30 composed of one cylinder 31 and one piston 32 has been described, but the compression mechanism portion 30 composed of two cylinders 31 and two pistons 32 may also be used. Considering that such a rotary compressor with two pistons is suitable for low-speed operation, it is also preferable that each vane 33 operates without leaving each piston 32.

[0148] In addition, as a device using the rotary compressor 1 suitable for low-speed operation, for example, it is also particularly applicable to an indoor air conditioner (household air conditioner) in an air conditioning device.

[0149] As described in this embodiment, according to the compression mechanism portion 30 in which the vane 33 operates without leaving the piston 32, an efficient rotary compressor can be achieved.

[0150] In particular, by setting the working fluid to R32 and the refrigerating oil to alkylbenzene oil, the compatibility is low, the lubricating performance can be ensured, and a good sliding state can be maintained. In addition, the same applies to the working fluid containing at least R32.

[0151] In addition, by setting the working fluid to carbon dioxide and the refrigerating oil to polyalkylene glycol oil, the compatibility is low, the lubricating performance can be ensured, and a good sliding state can be maintained. In addition, the same applies to the working fluid containing at least carbon dioxide.

[0152] In addition, by setting the working fluid to R290 and the refrigerating oil to polyalkylene glycol oil, the compatibility is low, the lubricating performance can be ensured, and a good sliding state can be maintained. In addition, the same applies to the working fluid containing at least R290.

[0153] In addition, the kinematic viscosity of the refrigerating oil is preferably 35 mm / s or less. For example, when the working fluid contains carbon dioxide or R290, a refrigerating oil with a kinematic viscosity exceeding 35 mm / s may also be used.

[0154] In addition, a rotary compressor in which the vane 33 operates without leaving the piston 32 can use R1234yf or HFO1123, a working fluid containing R1234yf, or a working fluid containing HFO1123. From the viewpoint of lubricating performance, in R1234yf or a working fluid containing R1234yf, it is preferable to use alkylbenzene oil as the refrigeration oil, and in HFO1123 or a working fluid containing HFO1123, it is preferable to use ester oil or essential oil as the refrigeration oil.

[0155] The reliability of the device of this embodiment in which the rotary compressor 1, the condenser 2, the decompression device 3, and the evaporator 4 are connected in a ring shape through piping is high.

[0156] Industrial availability

[0157] The device of the present invention using a rotary compressor is useful as a refrigeration cycle device such as a hot water heating device, an air conditioning device, a water heater, a cold storage, a display case, a cooler, a dehumidifier, or a freezer.

Claims

1. A rotary compressor, characterized in that: An electric motor part and a compression mechanism part are provided in a sealed container, An oil storage part for storing refrigeration oil is formed at the bottom in the sealed container, In the sealed container, there is a suction pipe for guiding the working fluid to the compression mechanism part, and a discharge pipe for guiding the working fluid compressed by the compression mechanism part to the outside of the sealed container, The working fluid compressed by the compression mechanism part is discharged into the sealed container and then guided from the discharge pipe to the outside of the sealed container, The electric motor part and the compression mechanism part are connected by a shaft, The compression mechanism part has a cylinder, a piston disposed in the cylinder, and a vane for partitioning the inside of the cylinder, The shaft has an eccentric part, A vane groove for disposing the vane is formed in the cylinder, The eccentric part is disposed in the cylinder, The piston is fitted with the eccentric part, The vane operates without leaving the piston, where Under the temperature condition of 25°C, the refrigeration oil and the working fluid are in a two-phase separation state.

2. The rotary compressor according to claim 1, characterized in that: A cylindrical groove with an arc angle exceeding 180° is formed on the piston, A cylindrical part disposed in the cylindrical groove is formed at the end of the vane.

3. The rotary compressor according to claim 1, characterized in that: Under the temperature condition of 0°C to 25°C, in the mixture in which the working fluid is maximally dissolved in the refrigeration oil, the proportion of the working fluid is less than 30 wt%.

4. The rotary compressor according to claim 1, characterized in that: There is no accumulator upstream of the suction pipe.

5. The rotary compressor according to claim 1, characterized in that: There is an accumulator upstream of the suction pipe, The volume of the liquid storage part of the accumulator is 2 times or less of the suction volume formed in the cylinder.

6. The rotary compressor according to any one of claims 1 to 5, characterized in that: The working fluid is R32 and the refrigeration oil is alkylbenzene oil.

7. The rotary compressor according to any one of claims 1 to 5, characterized in that: The working fluid is carbon dioxide and the refrigeration oil is polyalkylene glycol oil.

8. The rotary compressor according to any one of claims 1 to 5, characterized in that: The working fluid is R290 and the refrigeration oil is polyalkylene glycol oil.

9. An apparatus, characterized in that: The rotary compressor according to any one of claims 1 to 5 is used, The rotary compressor, condenser, decompression device and evaporator are connected in a ring by piping.

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