Compressor and refrigeration cycle device

Abstract

Provided is a twin rotary compressor that has a first cylinder in which a first compression chamber is provided and a second cylinder in which a second compression chamber is provided, said twin rotary compressor comprising: a first bearing that is provided on one end surface of the first cylinder; a second bearing that is provided on one end surface of the second cylinder; an intermediate partition plate that is provided between the first cylinder and the second cylinder and that partitions between the first compression chamber and the second compression chamber; a first small-diameter bolt that is inserted through the first bearing, that has a first male screw portion which is screwed into a first female screw portion formed in the first cylinder, and that fastens and fixes the first bearing and the first cylinder; a second small-diameter bolt that is inserted through the second bearing, that has a second male screw portion which is screwed into a second female screw portion formed in the second cylinder, and that fastens and fixes the second bearing and the second cylinder; and a large-diameter bolt that is inserted into a first screw insertion hole which is formed in the first cylinder and a second screw insertion hole which is formed in the second cylinder and that fastens and fixes the first bearing, the first cylinder, the intermediate partition plate, the second cylinder, and the second bearing.

Description

Compressor and refrigeration cycle device

[0001] The present disclosure relates to a compressor that compresses a refrigerant and a refrigeration cycle device.

[0002] Conventionally, there has been a twin rotary type compressor that includes a first compression mechanism having a front head, a first cylinder, and a middle plate fixed to the inner wall side of a casing, and a second compression mechanism having a rear head, a second cylinder, and a middle plate (see, for example, Patent Document 1).

[0003] In Patent Document 1, the front head has six through holes, and the first cylinder has six bolt holes. A first bolt group (six bolts) is threaded through the through holes in the front head into the bolt holes in the first cylinder, fastening the front head and the first cylinder together. The rear head has six through holes, and the second cylinder has three bolt holes and three through holes. A second bolt group (three bolts) is threaded through the through holes in the rear head into the bolt holes in the second cylinder, fastening the rear head and the second cylinder together. The middle plate has three through holes. A through bolt (three bolts) is threaded through the through holes in the rear head, the second cylinder, and the middle plate into the bolt holes in the first cylinder, fastening the rear head, the second cylinder, the middle plate, and the first cylinder together.

[0004] When assembling this twin rotary type compressor, the front head and the first cylinder are aligned, and then the front head and the first cylinder are fastened together with the first bolt group; the rear head and the second cylinder are aligned, and then the rear head and the second cylinder are fastened together with the second bolt group; and then the rear head, second cylinder, middle plate, and first cylinder are fastened together with through bolts.

[0005] In this way, the twin rotary compressor described above has bolt holes (internal threads) formed in the first cylinder and the second cylinder, so that the group of parts fastened to the front head and the first cylinder by the first group of bolts and the group of parts fastened to the rear head and the second cylinder by the second group of bolts can be easily fastened to each other using through bolts.

[0006] Japanese Patent Application Laid-Open No. 2020-2842

[0007] However, the twin rotary compressor of Patent Document 1 is configured so that two bolts (a first bolt group and a through bolt) are screwed into the same bolt hole of one cylinder (the first cylinder). This means that the axial length of the bolt hole needs to be longer than when one bolt is screwed into the same bolt hole of one cylinder, which poses the problem of having to configure the axial length of the cylinder to be long.

[0008] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a twin rotary type compressor and a refrigeration cycle device that can shorten the axial length of the cylinder compared to conventional compressors.

[0009] The compressor according to the present disclosure is a twin rotary type compressor including, in a container, a compression mechanism unit having a first cylinder with a first compression chamber provided therein and a second cylinder with a second compression chamber provided therein, an electric motor unit that drives the compression mechanism unit, and a rotary shaft that connects the compression mechanism unit and the electric motor unit, wherein the compressor further includes a first bearing that is provided on one end surface of the first cylinder and rotatably supports the rotary shaft, a second bearing that is provided on one end surface of the second cylinder and rotatably supports the rotary shaft, an intermediate partition plate that is provided between the other end surface of the first cylinder and the other end surface of the second cylinder that face each other and separates the first compression chamber and the second compression chamber, and a partition plate that is inserted through the first bearing and that connects the first cylinder and the second cylinder a first small-diameter bolt having a first male threaded portion threaded into a first female threaded portion formed on the first bearing and fastening the first bearing to the first cylinder; a second small-diameter bolt inserted from the second bearing and having a second male threaded portion threaded into a second female threaded portion formed on the second cylinder and fastening the second bearing to the second cylinder; and a large-diameter bolt inserted into a first screw-through hole formed on the first cylinder and a second screw-through hole formed on the second cylinder and fastening the first bearing, the first cylinder, the intermediate partition plate, the second cylinder, and the second bearing together, wherein the diameter of the first male threaded portion and the diameter of the second male threaded portion are smaller than the diameter of the male threaded portion of the large-diameter bolt.

[0010] A refrigeration cycle device according to the present disclosure includes the above-described compressor, an outdoor heat exchanger, a throttling device, and an indoor heat exchanger.

[0011] In the compressor and refrigeration cycle apparatus according to the present disclosure, a first male threaded portion of a first small-diameter bolt is threaded into a first female threaded portion of a first cylinder, a second male threaded portion of a second small-diameter bolt is threaded into a second female threaded portion of a second cylinder, and large-diameter bolts are inserted into the first screw through hole of the first cylinder and the second screw through hole of the second cylinder. In other words, because one bolt is threaded into the same bolt hole of one cylinder, the axial length of the cylinder can be shortened compared to when two bolts are threaded into the same bolt hole of one cylinder. Furthermore, the first bearing and the first cylinder are fastened together by the first male threaded portion of the first small-diameter bolt, which has a smaller diameter than the male threaded portion of the large-diameter bolt, and the first female threaded portion of the first cylinder. Furthermore, the second bearing and the second cylinder are fastened together by the second male threaded portion of a second small-diameter bolt, which has a smaller diameter than the male threaded portion of the large-diameter bolt, and the second female threaded portion of the second cylinder. In terms of fastening strength, the threading depth of the male thread portion into the cylinder is desirably at least 0.5 of the diameter of the male thread. Therefore, when small-diameter bolts (first small-diameter bolt and second small-diameter bolt) are used to configure the threading depth of the male thread portion into the first and second cylinders to be at least 0.5 of the diameter of the male thread, respectively, the threading depth of the male thread portion into the first and second cylinders can be reduced compared to when large-diameter bolts are used to configure the threading depth of the first and second cylinders to be at least 0.5 of the diameter of the male thread. In other words, because the threading depth of the first and second male thread portions into the first and second cylinders can be shortened, the axial length of the first and second cylinders can be shortened compared to conventional methods.

[0012] 6 is a schematic configuration diagram of a refrigeration cycle device including a compressor according to embodiment 1. FIG. 7 is a schematic vertical cross-sectional view showing a compressor according to embodiment 1. FIG. 8 is a schematic cross-sectional view showing a first compression section of the compressor according to embodiment 1 as viewed from above. FIG. 9 is a schematic cross-sectional view showing a second compression section of the compressor according to embodiment 1 as viewed from below. FIG. 10 is a schematic vertical cross-sectional view showing an enlarged view of the periphery of a main part of a bearing of the compressor according to embodiment 1. FIG. 11 is a schematic view showing a bearing of the compressor according to embodiment 1 as viewed from above. FIG. 12 is a schematic view showing a second bearing of the compressor according to embodiment 1 as viewed from below. FIG. 13 is a schematic vertical cross-sectional view showing an enlarged view of the periphery of a main part of a compression mechanism section of the compressor according to embodiment 1. FIG. 14 is a schematic view of a second discharge section projected onto the bearing of FIG. 6. FIG. 15 is a schematic vertical cross-sectional view showing an enlarged view of the periphery of a main part of a compression mechanism section of a conventional compressor. FIG. 16 is a schematic vertical cross-sectional view showing an enlarged view of the periphery of a main part of a compression mechanism section of a compressor according to embodiment 2. FIG. 17 is a schematic view of a bearing of a compressor according to embodiment 3 as viewed from above. FIG. 18 is a schematic view of a bearing of a compressor according to embodiment 4 as viewed from above.

[0013] Hereinafter, embodiments of a compressor according to the present disclosure will be described with reference to the drawings. Note that the present disclosure is not limited to the embodiments described below. Furthermore, in the following drawings, including FIG. 1, the dimensional relationships between components may differ from the actual ones. Furthermore, in the following description, terms indicating directions are used as appropriate to facilitate understanding of the present disclosure. However, these terms are for the purpose of explaining the present disclosure and do not limit the present disclosure. Examples of terms indicating directions include "up," "down," "right," "left," "front," and "rear." Note that in some drawings, hatching in cross-sectional views is partially omitted.

[0014] Embodiment 1. Fig. 1 is a schematic diagram of a refrigeration cycle apparatus 1 including a compressor 6 according to embodiment 1. The refrigeration cycle apparatus 1 including a compressor 6 according to embodiment 1 will be described below with reference to Fig. 1. The refrigeration cycle apparatus 1 is, for example, an air conditioner. The refrigeration cycle apparatus 1 includes an outdoor unit 2 installed outside an air-conditioned space and an indoor unit 3 installed within the air-conditioned space. The outdoor unit 2 includes a compressor 6, a flow path switching device 7, an outdoor heat exchanger 8, an outdoor blower 9, and an expansion device 10. The indoor unit 3 includes an indoor heat exchanger 11 and an indoor blower 12. Note that the expansion device 10 may be provided in the indoor unit 3 instead of the outdoor unit 2.

[0015] A compressor 6, a flow switching device 7, an outdoor heat exchanger 8, a throttling device 10, and an indoor heat exchanger 11 are connected in sequence by refrigerant piping 5 to form a refrigerant circuit 4 through which the refrigerant circulates.

[0016] The compressor 6 draws in a low-temperature, low-pressure refrigerant, compresses it, and discharges it into a high-temperature, high-pressure refrigerant. The flow path switching device 7 is, for example, a four-way valve that switches the refrigerant flow direction to switch between cooling and heating operation. Note that the flow path switching device 7 may be a combination of a two-way valve and a three-way valve instead of a four-way valve. The outdoor heat exchanger 8 functions as an evaporator or a condenser, exchanging heat between the air and the refrigerant to evaporate and gasify the refrigerant or condense and liquefy the refrigerant. The outdoor heat exchanger 8 functions as an evaporator during heating operation and as a condenser during cooling operation. The outdoor blower 9 is located near the outdoor heat exchanger 8 and sends outdoor air to the outdoor heat exchanger 8. The expansion device 10 reduces the pressure of the refrigerant and expands it. The throttling device 10 is, for example, an electronic expansion valve whose throttle opening can be adjusted. By adjusting the opening, the pressure of the refrigerant flowing into the indoor heat exchanger 11 is controlled during cooling operation, and the pressure of the refrigerant flowing into the outdoor heat exchanger 8 is controlled during heating operation. The indoor heat exchanger 11 functions as an evaporator or a condenser, exchanging heat between the air and the refrigerant to evaporate and gasify the refrigerant or condense and liquefy the refrigerant. The indoor heat exchanger 11 functions as a condenser during heating operation and as an evaporator during cooling operation. The indoor blower 12 is provided near the indoor heat exchanger 11 and sends indoor air to the indoor heat exchanger 11.

[0017] (Operation Modes, Cooling Operation) Next, the operation modes of the refrigeration cycle apparatus 1 will be described. First, the cooling operation will be described. In the cooling operation, the flow path switching device 7 is switched so that the discharge side of the compressor 6 is connected to the outdoor heat exchanger 8, as shown by the dashed line in FIG. 1 . In the cooling operation, the refrigerant drawn into the compressor 6 is compressed by the compressor 6 and discharged in a high-temperature, high-pressure gas state. The high-temperature, high-pressure gas refrigerant discharged from the compressor 6 passes through the flow path switching device 7 and flows into the outdoor heat exchanger 8, which functions as a condenser. In the outdoor heat exchanger 8, the refrigerant exchanges heat with outdoor air sent by the outdoor blower 9, condensing and liquefying it. The condensed liquid refrigerant flows into the expansion device 10, where it expands and decompresses to become a low-temperature, low-pressure, two-phase gas-liquid refrigerant. The refrigerant in the gas-liquid two-phase state then flows into the indoor heat exchanger 11, which functions as an evaporator, where it exchanges heat with the indoor air sent by the indoor blower 12, evaporating and gasifying. At this time, the indoor air is cooled, and cooling is performed in the room. The evaporated refrigerant in a low-temperature, low-pressure gas state passes through the flow switching device 7 and is drawn into the compressor 6.

[0018] (Operation Mode, Heating Operation) Next, the heating operation of the refrigeration cycle apparatus 1 will be described. In the heating operation, the flow path switching device 7 is switched so that the discharge side of the compressor 6 is connected to the indoor heat exchanger 11, as shown by the solid line in FIG. 1 . In the heating operation, the refrigerant drawn into the compressor 6 is compressed by the compressor 6 and discharged in a high-temperature, high-pressure gas state. The high-temperature, high-pressure gas refrigerant discharged from the compressor 6 passes through the flow path switching device 7 and flows into the indoor heat exchanger 11, which functions as a condenser. In the indoor heat exchanger 11, the refrigerant exchanges heat with indoor air sent by the indoor blower 12, condensing and liquefying. At this time, the indoor air is heated, and heating is performed in the room. The condensed liquid refrigerant flows into the expansion device 10, where it expands and decompresses to become a low-temperature, low-pressure, two-phase gas-liquid refrigerant. The refrigerant in the gas-liquid two-phase state then flows into the outdoor heat exchanger 8, which functions as an evaporator, where it exchanges heat with outdoor air sent by the outdoor blower 9 and evaporates and gasifies. The evaporated refrigerant in a low-temperature, low-pressure gas state passes through the flow switching device 7 and is drawn into the compressor 6.

[0019] FIG. 2 is a schematic vertical cross-sectional view showing the compressor 6 according to the first embodiment. FIG. 3 is a schematic cross-sectional view of the first compression section 30a of the compressor 6 according to the first embodiment, viewed from above. FIG. 4 is a schematic cross-sectional view of the second compression section 30b of the compressor 6 according to the first embodiment, viewed from below. FIG. 5 is a schematic vertical cross-sectional view of an enlarged view of the periphery of a main part of the first bearing 40 of the compressor 6 according to the first embodiment. FIG. 6 is a schematic view of the first bearing 40 of the compressor 6 according to the first embodiment, viewed from above. FIG. 7 is a schematic view of the second bearing 50 of the compressor 6 according to the first embodiment, viewed from below. FIG. 8 is a schematic vertical cross-sectional view of an enlarged view of the periphery of a main part of the compression mechanism section 30 of the compressor 6 according to the first embodiment. Note that for ease of explanation, the first discharge muffler 27 is not shown in FIG. 6, and the second discharge muffler 28 is not shown in FIG. 7. 6 and 7, the reference numerals in parentheses indicate the reference numerals of the bolts to be inserted into the holes indicated by the reference numerals to the left of them.

[0020] Next, the compressor 6 will be described in detail. As shown in Fig. 2, the compressor 6 includes a container 20, a discharge pipe 22, a suction section 23, an electric motor section 24, a compression mechanism section 30, a rotating shaft 25, an oil separator 26, a first bearing 40, a second bearing 50, a first discharge muffler 27, and a second discharge muffler 28. In the first embodiment, the compressor 6 is a twin rotary compressor having a first cylinder 31 and a second cylinder 71.

[0021] (Container 20) The container 20 is a sealed container that forms the outer shell of the compressor 6, and has an oil reservoir 21 formed in the lower part to store refrigerating machine oil. The refrigerating machine oil is supplied to each sliding part of the compressor 6 to lubricate each sliding part.

[0022] (Discharge Pipe 22 ) The discharge pipe 22 is provided at the top of the container 20 and discharges the compressed refrigerant to the outside of the container 20 .

[0023] (Suction Section 23) The suction section 23 draws refrigerant into the container 20 and includes a suction pipe 23a, a suction muffler 23b, and two outlet pipes 23c. The suction pipe 23a is connected to an accumulator (not shown) or the like and introduces the refrigerant flowing in from the accumulator or the like into the suction muffler 23b. The suction muffler 23b is connected to the suction pipe 23a and separates and stores the liquid refrigerant from the refrigerant flowing in from the suction pipe 23a and distributes the gas refrigerant to each outlet pipe 23c. The two outlet pipes 23c are each connected to the suction muffler 23b and introduce the refrigerant flowing in from the suction muffler 23b into the compression mechanism 30.

[0024] (Motor unit 24) The motor unit 24 is provided at the top inside the container 20, and its rotational frequency is changed by inverter control or the like. It has a stator 24a and a rotor 24b. The stator 24a has a cylindrical shape, and its outer peripheral surface is fixed to the inner wall of the container 20. A coil (not shown) is wound around the stator 24a, and power is supplied from an external power source (not shown). The rotor 24b has a cylindrical shape, and is disposed at an interval on the inner peripheral portion of the stator 24a. The rotor 24b rotates when power is supplied to the stator 24a.

[0025] (Compression Mechanism 30) The compression mechanism 30 is provided in a lower portion inside the container 20 and compresses the refrigerant. In the first embodiment, the compression mechanism 30 has an upper first compression section 30a, a lower second compression section 30b, and an intermediate partition plate 34 connecting the first compression section 30a and the second compression section 30b. As shown in FIG. 3, the first compression section 30a has a first cylinder 31, a first piston 32, and a vane 33. As shown in FIG. 4, the second compression section 30b has a second cylinder 71, a second piston 72, and a vane 73.

[0026] (First Cylinder 31) As shown in FIG. 3 , the first cylinder 31 is fixed to the inner wall of the container 20 and is an annular member having a suction hole 31a through which the drawn refrigerant passes and a compression hole 31c connected to the suction hole 31a. The first cylinder 31 also has a vane groove 31b to which a vane 33 is attached. The first cylinder 31 also has a discharge notch 31d through which the compressed refrigerant is discharged. The discharge notch 31d is inclined, for example, at 45° with respect to the axial direction of the rotary shaft 25. The discharge notch 31d is also formed at an angle relative to the extension direction of the vane 33. In FIG. 3 , the discharge notch 31d is formed at an angle in the direction opposite the extension direction of the vane 33 from the suction hole 31a.

[0027] (First Piston 32) The first piston 32 is an annular member that is inserted into the compression hole 31c of the first cylinder 31 and has an insertion hole 32a formed therein, into which the rotary shaft 25 is inserted. The first piston 32 forms a first compression chamber 35, which is a cylindrical space that compresses refrigerant, between the first piston 32 and the first cylinder 31. The axial end of the peripheral edge of the insertion hole 32a of the first piston 32 is chamfered to form a chamfered portion 32b. The first eccentric portion 25a of the rotary shaft 25 is inserted into the insertion hole 32a of the first piston 32. As a result, the first piston 32 rotates eccentrically in conjunction with the rotation of the rotary shaft 25.

[0028] (Vane 33) The vane 33 is a rod-shaped member that extends radially and is attached to a vane groove 31b formed in the first cylinder 31, and presses against the first piston 32 to separate the first compression chamber 35. The vane 33 reciprocates radially while sliding inside the vane groove 31b.

[0029] (Intermediate Partition Plate 34) As shown in FIG. 2, the intermediate partition plate 34 is a plate-shaped member that is provided between the lower end surface of the first cylinder 31 and the upper end surface of the second cylinder 71, which face each other, and separates the first compression chamber 35 from the second compression chamber 75 described later.

[0030] (Second Cylinder 71) As shown in FIG. 4, the second cylinder 71 is an annular member having a suction hole 71a through which the drawn refrigerant passes and a compression hole 71c connected to the suction hole 71a. The second cylinder 71 also has a vane groove 71b into which a vane 73 is attached. The second cylinder 71 also has a discharge notch 71d through which the compressed refrigerant is discharged. The discharge notch 71d is inclined, for example, at 45° with respect to the axial direction of the rotary shaft 25. The discharge notch 71d is also formed at an angle relative to the extension direction of the vane 73. In FIG. 4, the discharge notch 71d is also formed at an angle in the direction opposite the extension direction of the vane 73 from the suction hole 71a.

[0031] (Second Piston 72) The second piston 72 is an annular member that is inserted into the compression hole 71c of the second cylinder 71 and has an insertion hole 72a formed therein, into which the rotary shaft 25 is inserted. The second piston 72 forms a second compression chamber 75, which is a cylindrical space that compresses refrigerant, between the second piston 72 and the second cylinder 71. The axial end of the peripheral edge of the insertion hole 72a of the second piston 72 is chamfered to form a chamfered portion 72b. The second eccentric portion 25b of the rotary shaft 25 is inserted into the insertion hole 72a of the second piston 72. As a result, the second piston 72 rotates eccentrically in conjunction with the rotation of the rotary shaft 25.

[0032] (Rotating Shaft 25) As shown in Fig. 2, the rotating shaft 25 is a cylindrical member provided inside the container 20 at the center of the container 20, and connects the electric motor unit 24 and the compression mechanism unit 30. The rotating shaft 25 has a first eccentric portion 25a that is inserted into the insertion hole 32a of the first piston 32, and a second eccentric portion 25b that is inserted into the insertion hole 72a of the second piston 72. The first eccentric portion 25a and the second eccentric portion 25b are each cylindrical members that are thicker than the rotating shaft 25, and their centers are eccentric from the center of the rotating shaft 25. In other words, when the rotating shaft 25 rotates, the first eccentric portion 25a and the second eccentric portion 25b rotate eccentrically around the center of the rotating shaft 25. In this way, the rotating shaft 25 is connected to the electric motor unit 24 and drives it to rotate, and transmits the rotational force of the electric motor unit 24 to the first piston 32 via the first eccentric portion 25a and to the second piston 72 via the second eccentric portion 25b.

[0033] As shown in Figures 3 and 4, the first eccentric portion 25a and the second eccentric portion 25b are arranged in positions symmetrical with respect to the center point of the rotating shaft 25. In Figure 3, the lower side is the front side of the compressor 6 and the upper side is the rear side of the compressor 6, while in Figure 4, the upper side is the front side of the compressor 6 and the lower side is the rear side of the compressor 6. An oil passage (not shown) extending in the axial direction is formed inside the rotating shaft 25. Oil pumped up from the oil reservoir 21 flows through the oil passage. In addition, a plurality of oil supply holes (not shown) connected to the oil passage and extending radially from the oil passage are formed inside the rotating shaft 25. Refrigeration oil is introduced into each sliding part through the oil supply hole to lubricate each sliding part.

[0034] (Oil separator 26) As shown in Fig. 2, the oil separator 26 is a disk-shaped member having a diameter larger than that of the rotating shaft 25, and is fitted onto the upper part of the rotating shaft 25. When the gaseous refrigerant containing refrigeration oil rises toward the discharge pipe 22, the oil separator 26 blocks the flow path, causing the refrigerant and the refrigeration oil to collide and separate. As a result, the oil separator 26 drops the separated refrigeration oil to the bottom of the container 20, and guides only the refrigerant to the discharge pipe 22.

[0035] 2, the first bearing 40 is provided on the upper end surface of the first cylinder 31 and rotatably supports the rotating shaft 25. The first bearing 40 is a cylindrical member and has a base 41 fixed to the upper end surface of the first cylinder 31 of the first compression section 30a by a first small-diameter bolt 61 and a large-diameter bolt 63, and a tubular portion 42 that has a smaller diameter than the base 41 and extends axially from the inner peripheral edge of the base 41. The rotating shaft 25 is rotatably supported by being inserted into the inner peripheral portions of the base 41 and the tubular portion 42.

[0036] As shown in FIGS. 5 and 6 , a first discharge portion 43 is provided on the base 41 of the first bearing 40. The first discharge portion 43 includes a valve seat 46, a first discharge valve 44, and a first stationary valve 45. The valve seat 46 is a portion where a first discharge hole 46a connected to the discharge notch 31d formed in the first cylinder 31 is formed. The first discharge valve 44 is a leaf spring provided on the valve seat 46 and opens and closes the first discharge hole 46a. The first discharge valve 44 opens the first discharge hole 46a when the pressure in the first discharge hole 46a reaches or exceeds a predetermined pressure. The first stationary valve 45 presses the first discharge valve 44. When the pressure in the first discharge hole 46a reaches or exceeds the predetermined pressure, the first stationary valve 45 increases its pressing force on the first discharge valve 44, and the first discharge valve 44 is released from its pressing force. Hereinafter, the first discharge valve 44 and the first stationary valve 45 will be collectively referred to as the first discharge valve.

[0037] 2, the second bearing 50 is provided on the lower end surface of the second cylinder 71 and rotatably supports the rotating shaft 25. The second bearing 50 is a cylindrical member and has a base 51 fixed to the lower end surface of the second cylinder 71 of the second compression section 30b by a second small-diameter bolt 62 and a large-diameter bolt 63, and a tubular portion 52 that has a smaller diameter than the base 51 and extends axially from the inner peripheral edge of the base 51. The rotating shaft 25 is rotatably supported by being inserted into the inner peripheral portions of the base 51 and the tubular portion 52.

[0038] As shown in FIG. 7 , the base 51 of the second bearing 50 is provided with a second discharge portion 53. The second discharge portion 53 includes a valve seat (not shown), a second discharge valve 48, and a second stationary valve 49. The valve seat is a portion where the second discharge hole 47a, which is connected to the discharge notch 71d formed in the second cylinder 71, is formed. The second discharge valve 48 is a leaf spring provided on the valve seat and opens and closes the second discharge hole 47a. The second discharge valve 48 opens the second discharge hole 47a when the pressure in the second discharge hole 47a reaches or exceeds a predetermined pressure. The second stationary valve 49 presses the second discharge valve 48. When the pressure in the second discharge hole 47a reaches or exceeds the predetermined pressure, the second stationary valve 49 increases its pressing force on the second discharge valve 48, thereby releasing the pressure on the second discharge valve 48. Hereinafter, the second discharge valve 48 and the second stationary valve 49 will be collectively referred to as the second discharge valve.

[0039] (First Discharge Muffler 27, Second Discharge Muffler 28) As shown in FIG. 2 , the first discharge muffler 27 is a dome-shaped member having a hollow portion. It is attached to the upper surface of the base 41 of the first bearing 40 and suppresses noise amplified by resonance occurring in the space inside the container 20. A hole (not shown) through which the rotating shaft 25 is inserted is formed in the center of the first discharge muffler 27. Bolt holes (not shown) through which bolts are inserted are formed on the outer periphery of the first discharge muffler 27. The second discharge muffler 28 is a dome-shaped member having a hollow portion. It covers the lower surface of the base 51 of the second bearing 50 and the bottom of the rotating shaft 25 and suppresses noise amplified by resonance occurring in the space inside the container 20. Bolt holes (not shown) through which bolts are inserted are formed on the outer periphery of the second discharge muffler 28.

[0040] (Operation of Compressor 6) Next, the operation of compressor 6 according to the first embodiment will be described with reference to FIGS. 2 to 4. When power is supplied to stator 24a, rotor 24b rotates. This rotates rotary shaft 25 fixed to rotor 24b, causing first eccentric portion 25a and second eccentric portion 25b of rotary shaft 25 to rotate eccentrically. When first eccentric portion 25a rotates eccentrically, first piston 32, into which first eccentric portion 25a is inserted, rotates eccentrically within compression hole 31c of first cylinder 31. Furthermore, vane 33 attached to first cylinder 31 moves by entering and exiting vane groove 31b, thereby separating first compression chamber 35 without interfering with the eccentric rotation of first piston 32. The volume of first compression chamber 35 gradually decreases due to the eccentric rotation of first piston 32, thereby compressing the refrigerant in first compression chamber 35. Similarly, when second eccentric portion 25b rotates eccentrically, second piston 72, into which second eccentric portion 25b is inserted, rotates eccentrically inside compression hole 71c of second cylinder 71. Furthermore, vane 73 attached to second cylinder 71 moves by entering and exiting vane groove 71b, and therefore separates second compression chamber 75 without interfering with the eccentric rotation of second piston 72. The volume of second compression chamber 75 gradually decreases due to the eccentric rotation of second piston 72, thereby compressing the refrigerant inside second compression chamber 75.

[0041] In the first embodiment, the first eccentric portion 25a and the second eccentric portion 25b are arranged at positions symmetrical with respect to the center point of the rotation shaft 25, as shown in Figures 3 and 4. That is, the first eccentric portion 25a and the second eccentric portion 25b have a phase angle that is shifted by 180°. Therefore, the phase angle between the first piston 32 into which the first eccentric portion 25a is inserted and the second piston 72 into which the second eccentric portion 25b is inserted is also shifted by 180°. This reduces the axial load, improving the reliability of the compressor 6, and also reduces torque fluctuations and vibrations in the rotational direction.

[0042] (Refrigerant Flow) Next, the flow of refrigerant in the compressor 6 will be described with reference to FIG. 2 . Refrigerant drawn into the suction pipe 23a is separated into gaseous and liquid refrigerant by the suction muffler 23b. Only the gaseous refrigerant flows through the two outlet pipes 23c and into the suction hole 31a formed in the first cylinder 31 and the suction hole 71a formed in the second cylinder 71. The refrigerant that flows into the suction hole 31a flows into the first compression chamber 35. The eccentrically rotating first piston 32 then continuously reduces the volume of the first compression chamber 35, compressing the refrigerant. Similarly, the refrigerant that flows into the suction hole 71a flows into the second compression chamber 75. The eccentrically rotating second piston 72 then continuously reduces the volume of the second compression chamber 75, compressing the refrigerant.

[0043] The refrigerant compressed in the first compression chamber 35 and brought to a high-temperature, high-pressure state passes through the discharge notch 31d of the first cylinder 31 and reaches the first discharge hole 46a of the first bearing 40. When the pressure in the first discharge hole 46a reaches or exceeds a predetermined pressure, the first discharge valve 44 presses the first stationary valve 45. When the first stationary valve 45 opens, the refrigerant flows from the first discharge valve 44 into the space between the first discharge muffler 27 and the first bearing 40. The flowing-out refrigerant flows from the first discharge muffler 27 into the container 20, passes through a gap in the motor unit 24, and reaches the discharge pipe 22. The refrigerant that reaches the discharge pipe 22 is then discharged into the refrigerant circuit 4. Similarly, the refrigerant compressed in the second compression chamber 75 and brought to a high-temperature, high-pressure state passes through the discharge notch 71d of the second cylinder 71 and reaches the second discharge hole 47a of the second bearing 50. When the pressure in the second discharge hole 47a reaches or exceeds a predetermined pressure, the second discharge valve 48 presses the second stationary valve 49, and when the second stationary valve 49 opens, the refrigerant flows from the second discharge valve 48 into the space between the second discharge muffler 28 and the second bearing 50. The outflowing refrigerant flows from the second discharge muffler 28 into the container 20, passes through a gap in the electric motor section 24, and reaches the discharge pipe 22. The refrigerant that has reached the discharge pipe 22 passes through the discharge pipe 22 and is discharged into the refrigerant circuit 4.

[0044] (Flow of Refrigerant Oil) Next, the flow of refrigerant oil in the compressor 6 will be described with reference to Figure 2. The rotation of the rotating shaft 25 acts as a centrifugal pump, and the refrigerant oil stored in the oil sump 21 is sucked up into an oil passage (not shown) formed inside the rotating shaft 25. The refrigerant oil passing through the oil passage passes through each oil supply hole (not shown) and flows into each sliding part. The refrigerant oil then lubricates each sliding part.

[0045] Here, the sliding parts include, for example, a portion where the rotating shaft 25 and the first piston 32 contact each other, a portion where the rotating shaft 25 and the first bearing 40 contact each other, a portion where the rotating shaft 25 and the second bearing 50 contact each other, a portion where the rotating shaft 25 and the intermediate partition plate 34 contact each other, a portion where the first piston 32 and the first cylinder 31 contact each other, a portion where the first piston 32 and the first bearing 40 contact each other, a portion where the first piston 32 and the second bearing 50 contact each other, and a portion where the first piston 32 and the intermediate partition plate 34 contact each other. This prevents damage to the members due to direct contact between the members and also prevents refrigerant leakage.

[0046] (Fastening of Compression Mechanism 30) As shown in Fig. 8 , the first small diameter bolt 61 has a first male thread portion 61a that is screwed into the first female thread portion 36 formed in the first cylinder 31. Furthermore, as shown in Fig. 6 , the first bearing 40 has a first bearing eccentric bolt through hole 57 into which the first male thread portion 61a of the first small diameter bolt 61 is inserted. The first male thread portion 61a of the first small diameter bolt 61 is inserted through the first bearing eccentric bolt through hole 57 of the first bearing 40 and screwed into the first female thread portion 36. In this way, the first bearing 40 and the first cylinder 31 are fastened and fixed by the first small diameter bolt 61 having the first male thread portion 61a and the first female thread portion 36 of the first cylinder 31.

[0047] As shown in Fig. 8 , the second small diameter bolt 62 has a second male thread portion 62a that is screwed into the second female thread portion 76 formed in the second cylinder 71. Furthermore, as shown in Fig. 7 , the second bearing 50 has a second bearing eccentric bolt through hole 87 into which the second male thread portion 62a of the second small diameter bolt 62 is inserted. The second male thread portion 62a of the second small diameter bolt 62 is inserted through the second bearing eccentric bolt through hole 87 of the second bearing 50 and screwed into the second female thread portion 76. In this way, the second bearing 50 and the second cylinder 71 are fastened and fixed by the second small diameter bolt 62 having the second male thread portion 62a and the second female thread portion 76 of the second cylinder 71.

[0048] Here, the diameter of the first male thread portion 61a of the first small diameter bolt 61 and the diameter of the second male thread portion 62a of the second small diameter bolt 62 are configured to be the same. However, it is permissible for the diameter of the first male thread portion 61a of the first small diameter bolt 61 and the diameter of the second male thread portion 62a of the second small diameter bolt 62 to differ within the tolerance range. With this configuration, the same bolt can be used for the first small diameter bolt 61 and the second small diameter bolt 62, thereby reducing the number of types of parts.

[0049] As shown in FIG. 3 , the first cylinder 31 is formed with a first screw through-hole 91 into which the large-diameter bolt 63 is inserted. As shown in FIG. 4 , the second cylinder 71 is formed with a second screw through-hole 93 into which the large-diameter bolt 63 is inserted. As shown in FIG. 6 , the first bearing 40 is formed with a first bearing female thread 56 into which the male thread 63 a of the large-diameter bolt 63 is threaded and a first bearing coaxial bolt through-hole 58 into which the large-diameter bolt 63 is inserted. That is, in the first embodiment, the first bearing 40 corresponds to a nut having a female thread formed therein. As shown in FIG. 7 , the second bearing 50 is formed with a second bearing female thread 86 into which the male thread 63 a of the large-diameter bolt 63 is threaded and a second bearing coaxial bolt through-hole 88 into which the large-diameter bolt 63 is inserted. That is, in the first embodiment, the second bearing 50 corresponds to a nut having a female thread formed therein. Hereinafter, the first bearing female thread portion 56 and the second bearing female thread portion 86 will also be referred to as third female thread portions.

[0050] A large-diameter bolt 63 is inserted from the first bearing 40 side into the first bearing coaxial bolt through-hole 58 of the first bearing 40, the first screw through-hole 91 of the first cylinder 31, the second screw through-hole 93 of the second cylinder 71, and the second bearing female thread portion 86 of the second bearing 50. These members, arranged in this order from above in the axial direction: first bearing 40, first cylinder 31, intermediate partition plate 34, second cylinder 71, and second bearing 50, are fastened and fixed by the large-diameter bolt 63 having the male thread portion 63 a and the second bearing female thread portion 86 of the second bearing 50.

[0051] Furthermore, large-diameter bolts 63 are inserted from the second bearing 50 side into the first bearing female thread portion 56 of the first bearing 40, the first screw through-hole 91 of the first cylinder 31, the second screw through-hole 93 of the second cylinder 71, and the second bearing coaxial bolt through-hole 88 of the second bearing 50. These members, arranged in this order from above in the axial direction: first bearing 40, first cylinder 31, intermediate partition plate 34, second cylinder 71, and second bearing 50, are fastened and fixed by the large-diameter bolt 63 having the male screw portion 63 a and the first bearing female thread portion 56 of the first bearing 40.

[0052] Thus, in the first embodiment, there are large diameter bolts 63 inserted from the first bearing 40 side and large diameter bolts 63 inserted from the second bearing 50 side. Furthermore, in the first embodiment, there are two large diameter bolts 63 inserted from the first bearing 40 side and two large diameter bolts 63 inserted from the second bearing 50 side, and when the first bearing 40 is viewed from above, the large diameter bolts 63 inserted from the first bearing 40 side and the large diameter bolts 63 inserted from the second bearing 50 side are arranged alternately in the circumferential direction.

[0053] Furthermore, the first bearing 40 is formed with a first bearing refrigerant passage hole 55 as shown in Fig. 6. The second bearing 50 is formed with a second bearing refrigerant passage hole 85 as shown in Fig. 7. The first cylinder 31 is formed with a first cylinder refrigerant communication hole 92 as shown in Fig. 3. The second cylinder 71 is formed with a second cylinder refrigerant communication hole 94 as shown in Fig. 4. The first bearing refrigerant passage hole 55, the second bearing refrigerant passage hole 85, the first cylinder refrigerant communication hole 92, and the second cylinder refrigerant communication hole 94 form a path for discharging refrigerant discharged from the second bearing 50 from the same height as the first bearing 40 via these holes.

[0054] Fig. 10 is an enlarged schematic vertical cross-sectional view of the periphery of a main part of a compression mechanism 130 of a conventional compressor 106. In addition, in the first embodiment, as shown in Fig. 8, the diameters of the first small diameter bolt 61 and the second small diameter bolt 62 are smaller than the diameter of the large diameter bolt 63. In the conventional compressor 106 shown in Fig. 10, the diameters of the first small diameter bolt 61 and the second small diameter bolt 62 are the same as the diameter of the large diameter bolt 63.

[0055] According to the first embodiment, as shown in FIG. 8 , the diameters of the first small diameter bolt 61, the second small diameter bolt 62, the diameter of the hole provided in the first bearing 40 through which the first small diameter bolt 61 passes, the diameter of the hole provided in the second bearing 50 through which the second small diameter bolt 62 passes, the diameter of the hole provided in the first cylinder 31 through which the first small diameter bolt 61 is screwed, and the diameter of the hole provided in the second cylinder 71 through which the second small diameter bolt 62 is screwed are smaller than the diameters of the large diameter bolt 63, the diameter of the hole provided in the first bearing 40 through which the large diameter bolt 63 passes, the diameter of the hole provided in the first cylinder 31 through which the large diameter bolt 63 passes, the diameter of the hole provided in the intermediate partition plate 34 through which the large diameter bolt 63 passes, the diameter of the hole provided in the second cylinder 71 through which the large diameter bolt 63 passes, and the diameter of the hole provided in the second bearing 50 through which the large diameter bolt 63 is screwed.

[0056] In this way, the difference between the strength required for the large diameter bolt 63 for securing all of the first bearing 40, the second bearing 50, the first cylinder 31, and the second cylinder 71 and the strength required for the first small diameter bolt 61 for securing the first bearing 40 and the first cylinder 31 or the second small diameter bolt 62 for securing the second bearing 50 and the second cylinder 71 can be adjusted by reducing the diameter of the first small diameter bolt 61 or the second small diameter bolt 62, which makes it possible to reduce the diameter of the screw-through hole or screw fastening hole in the first bearing 40 or the second bearing 50, and reduces the space required for arranging the first small diameter bolt 61 or the second small diameter bolt 62 in the first bearing 40 or the second bearing 50.

[0057] Furthermore, the first cylinder 31 and the first bearing 40 are fastened together with first small-diameter bolts 61, the second cylinder 71 and the second bearing 50 are fastened together with second small-diameter bolts 62, and the fastened parts fastened together with the first small-diameter bolts 61 and the second small-diameter bolts 62 are fastened together with large-diameter bolts 63 that pass through all four of the first cylinder 31, the first bearing 40, the second cylinder 71, and the second bearing 50. This makes it possible to reduce the size of the fastening holes for the first small-diameter bolts 61 required to fasten the first cylinder 31 and the first bearing 40, or the fastening holes for the second small-diameter bolts 62 required to fasten the second cylinder 71 and the second bearing 50. As a result, the space required to provide the fastening holes can be reduced, thereby improving spatial flexibility compared to conventional designs.

[0058] Furthermore, in the past, two bolts were fastened to the first cylinder 31 or the second cylinder 71 in a manner facing each other. Therefore, in order to reduce stress applied to each bolt and the first cylinder 31 or the second cylinder 71 to which the bolts were fastened, it was necessary to provide an overlap for the two bolts in the first cylinder 31 or the second cylinder 71, which required the axial length of the first cylinder 31 or the second cylinder 71 to be long. However, in the first embodiment, the large-diameter bolt 63 is fastened while passing through all four of the first cylinder 31, the first bearing 40, the second cylinder 71, and the second bearing 50. This means that only the overlap for one large-diameter bolt 63 needs to be provided in the first bearing 40 or the second bearing 50, or in a nut member attached to the outside of the first bearing 40 or the second bearing 50. This shortens the overlap required for non-fastened objects, and as a result, the axial length of the first cylinder 31 or the second cylinder 71 can be shortened.

[0059] In the first embodiment, the first bearing 40 and the first cylinder 31 are fastened together by the first male thread portion 61a of the first small diameter bolt 61, which has a smaller diameter than the male thread portion 63a of the large diameter bolt 63, and the first female thread portion 36 formed on the first cylinder 31. In terms of fastening strength, it is desirable that the amount of threading of the first male thread portion 61a into the first cylinder 31 be 0.5 or more of the diameter of the first male thread portion 61a. Here, the amount of threading of the first male thread portion 61a into the first cylinder 31 refers to the length of the first male thread portion 61a within the first cylinder 31.

[0060] Therefore, for example, when the amount of threading into the first cylinder 31 using the first small diameter bolt 61 is set to 0.5 or more of the diameter of the first male thread portion 61a, the threading length can be shorter than when the amount of threading into the first cylinder 31 using the large diameter bolt 63 is set to 0.5 or more of the diameter of the male thread portion 63a, and as a result, the axial length of the first cylinder 31 can be shortened.

[0061] Furthermore, the diameter of the male thread portion 63a of the large diameter bolt 63 is larger than the diameters of the first female thread portion 36 and the second female thread portion 76. In other words, the diameters of the first small diameter bolt 61 and the second small diameter bolt 62 are smaller than the diameter of the large diameter bolt 63. Therefore, compared to a compressor that uses bolts inserted into the first bearing 40 and the second bearing 50 with the same diameter as the large diameter bolt 63, for example, the compressor 6 according to the first embodiment can reduce the diameters of the bolts inserted into the first bearing 40 and the second bearing 50, thereby reducing the space required for arranging the bolts relative to the first bearing 40 and the second bearing 50.

[0062] The second bearing 50 is formed with a second bearing female thread 86 into which the male thread 63 a of the large diameter bolt 63 is threaded, and the first bearing 40, the first cylinder 31, the intermediate partition plate 34, the second cylinder 71, and the second bearing 50 are fastened together by the second bearing 50 having the second bearing female thread 86 and the large diameter bolt 63. The first bearing 40 is formed with a first bearing female thread 56 into which the male thread 63 a of the large diameter bolt 63 is threaded, and the first bearing 40, the first cylinder 31, the intermediate partition plate 34, the second cylinder 71, and the second bearing 50 are fastened together by the first bearing 40 having the first bearing female thread 56 and the large diameter bolt 63. Therefore, no separate parts such as nuts are required to fasten together the first bearing 40, the first cylinder 31, the intermediate partition plate 34, the second cylinder 71, and the second bearing 50, and the number of parts constituting the compressor 6 can be reduced.

[0063] FIG. 9 is a schematic diagram of the second discharge portion 53 projected onto the first bearing 40 of FIG. 6 . Note that the second discharge portion 53 is indicated by a dashed line in FIG. 9 . The reference numerals in parentheses in FIG. 9 indicate the reference numerals of the bolts inserted into the holes indicated by the reference numerals to the left of them. As shown in FIG. 9 , the first discharge portion 43 and the second discharge portion 53 are arranged to face each other in the axial direction of the first cylinder 31. This increases the area in which bolt holes can be symmetrically arranged in the first bearing 40 and the second bearing 50, thereby increasing the degree of freedom in bolt hole arrangement and enabling the first bearing refrigerant channel hole 55 and the second bearing refrigerant channel hole 85 to be arranged over a larger area. To maximize the above-described effect, it is desirable that the first discharge portion 43 and the second discharge portion 53 be arranged to face each other entirely in the axial direction of the first cylinder 31. However, this is not a limitation; it is sufficient that they are arranged to face each other at least partially.

[0064] As shown in Fig. 6 , a total of six bolts are arranged in the following order, starting from the first small diameter bolt 61 on the left end, in the circumferential direction (clockwise direction) around the axis of the first cylinder 31 (the point where the two dashed dotted lines in Fig. 6 intersect): first small diameter bolt 61, large diameter bolt 63, large diameter bolt 63, first small diameter bolt 61, and large diameter bolt 63. A total of four large diameter bolts 63 are arranged. At the location where three consecutive large diameter bolts 63 are arranged, a first discharge hole 46a is located between two of the large diameter bolts 63. Furthermore, the four large diameter bolts 63 are arranged in different regions of the first cylinder 31, which are divided into four equal parts by a line (the two dashed dotted lines in Fig. 6 ) passing through the axis of the first cylinder 31.

[0065] In this way, by using not only the large-diameter bolts 63 but also the small-diameter first small-diameter bolts 61, the area in which the first discharge holes 46a can be arranged can be increased, thereby increasing the degree of freedom in the arrangement of the first discharge holes 46a. Furthermore, because the vicinity of the first discharge holes 46a, where the pressure in the first compression chamber 35 is highest, is fixed with three large-diameter bolts 63, it is possible to reduce insufficient fastening force during high-pressure operation of the compressor 6. Furthermore, by arranging the four large-diameter bolts 63 that fasten all of the first discharge muffler 27, first bearing 40, first cylinder 31, intermediate partition plate 34, second cylinder 71, second bearing 50, and second discharge muffler 28 in different regions of the first cylinder 31, it is possible to fasten them in a balanced manner.

[0066] 8, the first discharge muffler 27, the first bearing 40, and the first cylinder 31 are fastened together by the first small diameter bolt 61 and the first female thread portion 36 formed on the first cylinder 31. Therefore, the first discharge muffler 27, the first bearing 40, and the first cylinder 31 can be fastened together using only the first small diameter bolt 61, which has a small diameter, without relying on the large diameter bolt 63, which has a large diameter, making assembly easier.

[0067] Additionally, the second discharge muffler 28, the second bearing 50, and the second cylinder 71 are fastened together by the second small diameter bolt 62 and the second female thread portion 76 formed on the second cylinder 71. Therefore, the second discharge muffler 28, the second bearing 50, and the second cylinder 71 can be fastened together using only the second small diameter bolt 62, which has a small diameter, without relying on the large diameter bolt 63, which has a large diameter, making assembly easier.

[0068] Furthermore, in embodiment 1, after the first discharge muffler 27, the first bearing 40, and the first cylinder 31 are aligned, the first discharge muffler 27, the first bearing 40, and the first cylinder 31 are fastened and fixed together with the first small diameter bolt 61, and after the second discharge muffler 28, the second bearing 50, and the second cylinder 71 are aligned, the second discharge muffler 28, the second bearing 50, and the second cylinder 71 are fastened and fixed together with the second small diameter bolt 62, and then these components, arranged in this order: the first discharge muffler 27, the first bearing 40, the first cylinder 31, the intermediate partition plate 34, the second cylinder 71, the second bearing 50, and the second discharge muffler 28, are fastened and fixed together with the large diameter bolt 63.

[0069] As described above, the compressor 6 according to the first embodiment is a twin rotary type compressor 6 provided in the container 20 with the compression mechanism unit 30 having the first cylinder 31 with the first compression chamber 35 provided therein and the second cylinder 71 with the second compression chamber 75 provided therein, the electric motor unit 24 that drives the compression mechanism unit 30, and the rotating shaft 25 that connects the compression mechanism unit 30 and the electric motor unit 24, the compressor 6 also including the first bearing 40 provided on one end face of the first cylinder 31 and rotatably supporting the rotating shaft 25, the second bearing 50 provided on one end face of the second cylinder 71 and rotatably supporting the rotating shaft 25, the intermediate partition plate 34 that covers the other end faces of the first cylinder 31 and the second cylinder 71 that face each other and separates the first compression chamber 35 and the second compression chamber 75, and the intermediate partition plate 34 that is inserted through the first bearing 40 and connects the first cylinder 3 a first small-diameter bolt 61 having a first male threaded portion 61 a threaded into a first female threaded portion 36 formed on the second cylinder 71 and fastening the first bearing 40 and the first cylinder 31 together; a second small-diameter bolt 62 inserted through the second bearing 50 and having a second male threaded portion 62 a threaded into a second female threaded portion 76 formed on the second cylinder 71 and fastening the second bearing 50 and the second cylinder 71 together; and a large-diameter bolt 63 inserted into a first screw-through hole 91 formed in the first cylinder 31 and a second screw-through hole 93 formed in the second cylinder 71 and fastening the first bearing 40, the first cylinder 31, the intermediate partition plate 34, the second cylinder 71 and the second bearing 50 together, wherein the diameters of the first male threaded portion 61 a and the second male threaded portion 62 a are smaller than the diameter of the male threaded portion 63 a of the large-diameter bolt 63.

[0070] In the compressor 6 according to the first embodiment, the first male thread portion 61 a of the first small diameter bolt 61 is threaded into the first female thread portion 36 of the first cylinder 31, the second male thread portion 62 a of the second small diameter bolt 62 is threaded into the second female thread portion 76 of the second cylinder 71, and the large diameter bolt 63 is inserted into the first screw through hole 91 of the first cylinder 31 and the second screw through hole 93 of the second cylinder 71. In other words, because one bolt is threaded into the same bolt hole of one cylinder, the axial length of the cylinder can be shortened compared to when two bolts are threaded into the same bolt hole of one cylinder. Furthermore, the first bearing 40 and the first cylinder 31 are fastened and fixed together by the first male thread portion 61 a of the first small diameter bolt 61, which has a smaller diameter than the male thread portion 63 a of the large diameter bolt 63, and the first female thread portion 36 of the first cylinder 31. Furthermore, the second bearing 50 and the second cylinder 71 are fastened together by a second male thread portion 62a of a second small diameter bolt 62, which has a smaller diameter than the male thread portion 63a of the large diameter bolt 63, and a second female thread portion 76 of the second cylinder 71. In terms of fastening strength, it is desirable that the amount of screwing of the male thread portion into the cylinder be 0.5 or more of the diameter of the male thread portion. Therefore, when small diameter bolts (first small diameter bolt 61 and second small diameter bolt 62) are used to configure the threading amounts of the first male thread portion 61 a and the second male thread portion 62 a into the first cylinder 31 and the second cylinder 71 to be equal to or greater than 0.5 of the diameter of the first male thread portion 61 a and the second male thread portion 62 a, respectively, the threading amounts of the first male thread portion 61 a and the second male thread portion 62 a into the first cylinder 31 and the second cylinder 71 can be made smaller than when large diameter bolts 63 are used to configure the threading amounts of the first male thread portion 61 a and the second male thread portion 62 a into the first cylinder 31 and the second cylinder 71 to be equal to or greater than 0.5 of the diameter of the male thread portion 63 a. In other words, because the threading lengths of the first male thread portion 61 a and the second male thread portion 62 a into the first cylinder 31 and the second cylinder 71 can be shortened, the axial lengths of the first cylinder 31 and the second cylinder 71 can be made shorter than before.

[0071] In the compressor 6 according to the first embodiment, the diameter of the first male thread portion 61a and the diameter of the second male thread portion 62a are the same.

[0072] According to the compressor 6 of embodiment 1, this configuration allows the same bolt to be used for the first small diameter bolt 61 and the second small diameter bolt 62, thereby reducing the number of types of parts.

[0073] Furthermore, in the compressor 6 according to embodiment 1, a third female thread portion is formed in one of the first bearing 40 and the second bearing 50, and the first bearing 40, the first cylinder 31, the intermediate partition plate 34, the second cylinder 71, and the second bearing 50 are fastened and fixed together by screwing the male thread portion 63a of the large diameter bolt 63 into the third female thread portion.

[0074] According to the compressor 6 of embodiment 1, by adopting such a configuration, separate parts such as nuts are not required to fasten and fix the first bearing 40, the first cylinder 31, the intermediate partition plate 34, the second cylinder 71, and the second bearing 50, and the number of parts that make up the compressor 6 can be reduced.

[0075] Furthermore, the compressor 6 according to embodiment 1 is provided with a first discharge valve that opens and closes a first discharge hole 46a formed in the first bearing 40 and that discharges the refrigerant compressed in the first compression chamber 35, and a second discharge valve that opens and closes a second discharge hole 47a formed in the second bearing 50 and that discharges the refrigerant compressed in the second compression chamber 75, and the first discharge valve and the second discharge valve are arranged to face each other in the axial direction.

[0076] According to the compressor 6 of embodiment 1, this configuration makes it possible to increase the area in which bolt holes can be arranged symmetrically between the first bearing 40 and the second bearing 50, thereby increasing the degree of freedom in arranging the bolt holes, and further making it possible to arrange the first bearing refrigerant flow path holes 55 and the second bearing refrigerant flow path holes 85 over a larger area.

[0077] In addition, in the compressor 6 according to the first embodiment, a total of six bolts are arranged circumferentially around the axis of the first cylinder 31 in the following order: first small diameter bolt 61, large diameter bolt 63, large diameter bolt 63, large diameter bolt 63, first small diameter bolt 61, large diameter bolt 63. Of the three consecutively arranged large diameter bolts 63, a first discharge hole 46a is arranged between two of the large diameter bolts 63, and the four large diameter bolts 63 are arranged in different regions of the region obtained by dividing the first cylinder 31 into four equal parts by a straight line passing through the axis.

[0078] According to the compressor 6 of the first embodiment, this configuration allows the use of not only the large-diameter bolts 63 but also the small-diameter first small-diameter bolts 61, thereby increasing the area in which the first discharge holes 46a can be arranged, thereby increasing the degree of freedom in the arrangement of the first discharge holes 46a. Furthermore, because the vicinity of the first discharge holes 46a, where the pressure in the first compression chamber 35 is highest, is fixed with three large-diameter bolts 63, it is possible to reduce insufficient fastening force during high-pressure operation of the compressor 6. Furthermore, the four large-diameter bolts 63 that fasten all of the first discharge muffler 27, first bearing 40, first cylinder 31, intermediate partition plate 34, second cylinder 71, second bearing 50, and second discharge muffler 28 are arranged in different regions of the first cylinder 31, thereby allowing them to be fastened and fixed in a balanced manner.

[0079] Furthermore, the compressor 6 according to the first embodiment is provided with a first discharge muffler 27 that suppresses the noise generated when the refrigerant is discharged from the first discharge hole 46a, and the first discharge muffler 27, the first bearing 40, and the first cylinder 31 are fastened and fixed by a first small diameter bolt 61 and a first female thread portion 36.

[0080] According to the compressor 6 of embodiment 1, this configuration allows the first discharge muffler 27, the first bearing 40, and the first cylinder 31 to be fastened and fixed using only the first small diameter bolts 61, which have a small diameter, without relying on the large diameter bolts 63, making assembly easier.

[0081] Furthermore, the compressor 6 according to the first embodiment is provided with a second discharge muffler 28 that suppresses the noise generated when the refrigerant is discharged from the second discharge hole 47a, and the second discharge muffler 28, the second bearing 50, and the second cylinder 71 are fastened and fixed by a second small diameter bolt 62 and a second female thread portion 76.

[0082] According to the compressor 6 of embodiment 1, this configuration allows the second discharge muffler 28, the second bearing 50, and the second cylinder 71 to be fastened and fixed using only the second small diameter bolts 62, which have a smaller diameter, without relying on the large diameter bolts 63, making assembly easier.

[0083] The refrigeration cycle device 1 according to the present disclosure includes the compressor 6, the outdoor heat exchanger 8, the expansion device 10, and the indoor heat exchanger 11.

[0084] According to the refrigeration cycle device 1 of the first embodiment, the same effects as those of the compressor 6 described above can be obtained.

[0085] Embodiment 2. Hereinafter, embodiment 2 will be described, but explanations of parts that overlap with embodiment 1 will be omitted, and parts that are the same as or equivalent to embodiment 1 will be given the same reference numerals. Furthermore, embodiment 2 will be described mainly focusing on differences from embodiment 1.

[0086] 11 is an enlarged schematic vertical cross-sectional view of the periphery of a main part of the compression mechanism 30 of the compressor 6 according to the second embodiment. The second embodiment differs from the first embodiment in that the fastening members to the large diameter bolts 63 in the compressor 6 are nuts 64, rather than the first bearing 40 and the second bearing 50.

[0087] 11 , a nut 64 is provided on the male threaded portion 63a of the large diameter bolt 63. A female threaded portion 64a is formed in the nut 64, and the male threaded portion 63a of the large diameter bolt 63 is screwed into the female threaded portion 64a. The large diameter bolt 63 and the nut 64 fasten and fix the following components, which are arranged in this order: the first discharge muffler 27, the first bearing 40, the first cylinder 31, the intermediate partition plate 34, the second cylinder 71, the second bearing 50, and the second discharge muffler 28. Hereinafter, the female threaded portion 64a will also be referred to as the third female threaded portion.

[0088] Here, when large diameter bolt 63 is screwed into first bearing 40 and second bearing 50 to fasten them, it is necessary to provide threads in base 41 of first bearing 40 and base 51 of second bearing 50 for screwing in and fastening large diameter bolt 63. However, in embodiment 2, there is no need to provide threads in base 41 of first bearing 40 and base 51 of second bearing 50, and therefore the thicknesses of base 41 of first bearing 40 and base 51 of second bearing 50 can be made correspondingly thinner.

[0089] In this way, in the second embodiment, by setting the fastening target of the large diameter bolt 63 to the nut 64 instead of the first bearing 40 and the second bearing 50, it is not necessary to provide threads on the base 41 of the first bearing 40 and the base 51 of the second bearing 50 for fastening the large diameter bolt 63. As a result, the thickness of the base 41 of the first bearing 40 and the base 51 of the second bearing 50 can be made thinner, and the amount of material can be reduced accordingly, thereby enabling resource conservation.

[0090] As described above, the compressor 6 according to the second embodiment is provided with a nut 64 having a third female threaded portion formed thereon, and the male threaded portion 63a of the large diameter bolt 63 is screwed into the third female threaded portion, thereby fastening and fixing the first bearing 40, the first cylinder 31, the intermediate partition plate 34, the second cylinder 71, and the second bearing 50 together.

[0091] According to the compressor 6 of the second embodiment, this configuration eliminates the need to provide threads for fastening the large-diameter bolts 63 to the base 41 of the first bearing 40 and the base 51 of the second bearing 50. As a result, the thickness of the base 41 of the first bearing 40 and the base 51 of the second bearing 50 can be reduced, and the amount of material can be reduced accordingly, thereby enabling resource conservation.

[0092] Embodiment 3. Hereinafter, embodiment 3 will be described, but explanations of parts that overlap with embodiment 1 will be omitted, and parts that are the same as or equivalent to embodiment 1 will be given the same reference numerals. Furthermore, embodiment 3 will be described mainly with respect to differences from embodiment 1.

[0093] Fig. 12 is a schematic diagram of the first bearing 40 of the compressor 6 according to the third embodiment, viewed from above. For ease of explanation, the first discharge muffler 27 is not shown in Fig. 12. The reference numerals in parentheses in Fig. 12 indicate the reference numerals of the bolts to be inserted into the holes indicated by the reference numerals to the left of them.

[0094] In the first embodiment, a total of six bolts are arranged in the circumferential direction based on the axis of the first cylinder 31 in the order of first small diameter bolt 61, large diameter bolt 63, large diameter bolt 63, first small diameter bolt 61, and large diameter bolt 63, and where three consecutive large diameter bolts 63 are arranged, the first discharge hole 46a is arranged between two of the large diameter bolts 63. In contrast, in the third embodiment, as shown in Fig. 12 , a total of five bolts are arranged in the circumferential direction (clockwise direction) based on the axis of the first cylinder 31 (the point where the two dashed dotted lines in Fig. 12 intersect) based on the first small diameter bolt 61 at the left end in the order of first small diameter bolt 61, large diameter bolt 63, large diameter bolt 63, first small diameter bolt 61, and large diameter bolt 63, and a total of three large diameter bolts 63 are arranged. At the location where two consecutive large diameter bolts 63 are provided, the first discharge hole 46a is located between the two large diameter bolts 63. Furthermore, the three large diameter bolts 63 are located in different regions of the first cylinder 31 that are divided into four equal parts by a line (the two dashed dotted lines in FIG. 12 ) that passes through the axis of the first cylinder 31.

[0095] In this way, by using not only the large-diameter bolts 63 but also the small-diameter first small-diameter bolts 61, the area in which the first discharge holes 46a can be arranged can be increased, thereby increasing the degree of freedom in the arrangement of the first discharge holes 46a. Furthermore, because the vicinity of the first discharge holes 46a, which have the highest pressure in the first compression chamber 35, is fixed with three large-diameter bolts 63, it is possible to reduce insufficient fastening force during high-pressure operation of the compressor 6.

[0096] Furthermore, in embodiment 3, compared to embodiment 1, the number of bolt holes that need to be provided in the first bearing 40 and the second bearing 50 to allow the large diameter bolt 63 to pass through is reduced by one, and therefore the area in which the first discharge hole 46a can be arranged can be increased accordingly, thereby further increasing the freedom in the arrangement of the first discharge hole 46a.

[0097] As described above, the compressor 6 according to the third embodiment has a total of five bolts arranged circumferentially around the axis of the first cylinder 31 in the order of a first small diameter bolt 61, a large diameter bolt 63, a large diameter bolt 63, a first small diameter bolt 61, and a large diameter bolt 63, and the first discharge hole 46a is arranged between two successively arranged large diameter bolts 63, and the three large diameter bolts 63 are arranged in different regions of the region obtained by dividing the first cylinder 31 into four equal parts by a straight line passing through the axis.

[0098] According to the compressor 6 of the third embodiment, by using not only the large-diameter bolts 63 but also the small-diameter first small-diameter bolts 61, the area in which the first discharge holes 46a can be arranged can be increased, thereby increasing the degree of freedom in the arrangement of the first discharge holes 46a. Furthermore, because the area in the first compression chamber 35 near the first discharge holes 46a, which have the highest pressure, is fixed with three large-diameter bolts 63, it is possible to reduce a lack of fastening force during high-pressure operation of the compressor 6. Furthermore, compared to the first embodiment, the number of bolt holes that need to be provided in the first bearing 40 and the second bearing 50 to pass the large-diameter bolts 63 is reduced by one, and the area in which the first discharge holes 46a can be arranged can be increased accordingly, thereby further increasing the degree of freedom in the arrangement of the first discharge holes 46a. Furthermore, by arranging the three large diameter bolts 63 that fasten all of the first discharge muffler 27, first bearing 40, first cylinder 31, intermediate partition plate 34, second cylinder 71, second bearing 50, and second discharge muffler 28 in different areas of the four equal areas of the first cylinder 31, they can be fastened and fixed in a balanced manner.

[0099] Embodiment 4. Hereinafter, embodiment 4 will be described, but explanations of parts that overlap with embodiment 1 will be omitted, and parts that are the same as or equivalent to embodiment 1 will be given the same reference numerals. Furthermore, in embodiment 4, the differences from embodiment 1 will be mainly described.

[0100] Fig. 13 is a schematic diagram of the first bearing 40 of the compressor 6 according to the fourth embodiment, viewed from above. For ease of explanation, the first discharge muffler 27 is not shown in Fig. 13. The reference numerals in parentheses in Fig. 13 indicate the reference numerals of the bolts to be inserted into the holes indicated by the reference numerals to the left of them.

[0101] In the first embodiment, a total of six bolts are arranged in the circumferential direction based on the axis of the first cylinder 31 in the order of first small diameter bolt 61, large diameter bolt 63, large diameter bolt 63, first small diameter bolt 61, and large diameter bolt 63, and where three consecutive large diameter bolts 63 are arranged, the first discharge hole 46a is arranged between two of the large diameter bolts 63. In contrast, in the fourth embodiment, as shown in Fig. 13 , a total of four bolts are arranged in the circumferential direction (clockwise direction) based on the axis of the first cylinder 31 (the point where the two dashed dotted lines in Fig. 13 intersect), starting from the upper left first small diameter bolt 61, in the order of first small diameter bolt 61, large diameter bolt 63, first small diameter bolt 61, and large diameter bolt 63, and two large diameter bolts 63 are arranged. The two large diameter bolts 63 are arranged in different regions of the four equal regions of the first cylinder 31 divided by straight lines (two dotted lines in Figure 13) passing through the axis of the first cylinder 31.

[0102] In embodiment 4, compared to embodiment 1, the number of bolt holes that need to be provided in the first bearing 40 and the second bearing 50 to allow the large diameter bolt 63 to pass through is reduced by two, and therefore the area in which the first discharge hole 46a can be arranged can be increased accordingly, thereby further increasing the freedom in the arrangement of the first discharge hole 46a.

[0103] As described above, the compressor 6 according to the fourth embodiment has a total of four bolts arranged circumferentially around the axis of the first cylinder 31 in the order of the first small diameter bolt 61, the large diameter bolt 63, the first small diameter bolt 61, and the large diameter bolt 63, and the two large diameter bolts 63 are arranged in different regions of the four equal regions obtained by dividing the first cylinder 31 by a straight line passing through the axis.

[0104] According to compressor 6 of Embodiment 4, this configuration reduces the number of bolt holes that need to be provided in first bearing 40 and second bearing 50 to allow large diameter bolts 63 to pass through by two compared to Embodiment 1, and therefore the area in which first discharge holes 46 a can be arranged can be increased accordingly, further increasing the degree of freedom in the arrangement of first discharge holes 46 a. Furthermore, by arranging the two large diameter bolts 63 that fasten all of first discharge muffler 27, first bearing 40, first cylinder 31, intermediate partition plate 34, second cylinder 71, second bearing 50, and second discharge muffler 28 in different regions of the first cylinder 31 that are equally divided into four, these components can be fastened and fixed in a balanced manner.

[0105] Although the compressors 6 according to the first to fourth embodiments are configured such that the large diameter bolts 63 are inserted from the first bearing 40 side and the large diameter bolts 63 are inserted from the second bearing 50 side, the present invention is not limited to this. The compressors 6 according to the first to fourth embodiments may be configured such that the large diameter bolts 63 are inserted only from the first bearing 40 side, or may be configured such that the large diameter bolts 63 are inserted only from the second bearing 50 side.

[0106] Furthermore, the compressors 6 according to the first to fourth embodiments are configured to include two outlet pipes 23c, one of which is connected to the first compression chamber 35 of the first compression section 30a and the other of which is connected to the second compression chamber 75 of the second compression section 30b, but this is not limiting. The compressors 6 according to the first to fourth embodiments may be configured to include only one outlet pipe 23c, which is connected to the first compression chamber 35 of the first compression section 30a and branches from the flow path from the outlet pipe 23c to the first compression chamber 35 of the first compression section 30a, so that the refrigerant is supplied from the outlet pipe 23c to the second compression chamber 75 of the second compression section 30b. Alternatively, as another configuration, only one outlet pipe 23c may be provided, the outlet pipe 23c may be connected to the second compression chamber 75 of the second compression section 30b, and the outlet pipe 23c may be branched off from the flow path to the second compression chamber 75 of the second compression section 30b, and the refrigerant may be supplied from the outlet pipe 23c to the first compression chamber 35 of the first compression section 30a.

[0107] REFRIGERATION CYCLE DEVICE, 2 OUTDOOR UNIT, 3 INDOOR UNIT, 4 REFRIGERANTE CIRCUIT, 5 REFRIGERANTE PIPE, 6 COMPRESSOR, 7 FLOW CHANNEL SWITCHING DEVICE, 8 OUTDOOR HEAT EXCHANGER, 9 OUTDOOR BLOWER, 10 THROTTLE DEVICE, 11 INDOOR HEAT EXCHANGER, 12 INDOOR BLOWER, 20 CONTAINER, 21 OIL SUMPTUOUS WATER, 22 DISCHARGE PIPE, 23 SUCTION PORTION, 23a SUCTION PIPE, 23b SUCTION Muffler, 23c OUTLET PIPE, 24 MOTOR PORTION, 24a STATOR, 24b ROTOR, 25 ROTATING SHAFT, 25a FIRST ECCENTRIC PORTION, 25b SECOND ECCENTRIC PORTION, 26 OIL SEPARATOR, 27 FIRST DISCHARGE Muffler, 28 SECOND DISCHARGE Muffler, 30 COMPRESSION MECHANISM PORTION, 30a FIRST COMPRESSION PORTION, 30b SECOND COMPRESSION PORTION, 31 FIRST CYLINDER, 31a SUCTION HOLE, 31b Vane Gap, 31c Compression hole, 31d Discharge notch, 32 First piston, 32a Insertion hole, 32b Chamfered portion, 33 Vane, 34 Intermediate partition plate, 35 First compression chamber, 36 First female thread portion, 40 First bearing, 41 Base portion, 42 Cylinder portion, 43 First discharge portion, 44 First discharge valve, 45 First stationary valve, 46 Valve seat, 46a First discharge hole, 47a Second discharge hole, 48 Second discharge valve, 49 Second stationary valve, 50 Second bearing, 51 Base portion, 52 Cylinder portion, 53 Second discharge portion, 55 First bearing refrigerant flow path hole, 56 First bearing female thread portion, 57 First bearing eccentric bolt through hole, 58 First bearing coaxial bolt through hole, 60 Compressor, 61 First small diameter bolt, 61a First male thread portion, 62 Second small diameter bolt, 62a Second male thread portion, 63 large diameter bolt, 63a male thread portion, 64 nut, 64a female thread portion, 71 second cylinder, 71a suction hole, 71b vane groove, 71c compression hole, 71d discharge notch, 72 second piston, 72a insertion hole, 72b chamfered portion, 73 vane, 75 second compression chamber, 76 second female thread portion, 85 second bearing refrigerant flow path hole, 86 second bearing female thread portion, 87 second bearing eccentric bolt through hole, 88 second bearing coaxial bolt through hole, 91 first screw through hole, 92 first cylinder refrigerant communication hole, 93 second screw through hole, 94 second cylinder refrigerant communication hole, 106 compressor, 130 compression mechanism portion.

Claims

1. a compression mechanism including a first cylinder having a first compression chamber therein and a second cylinder having a second compression chamber therein; an electric motor unit that drives the compression mechanism unit; a rotary shaft that connects the compression mechanism unit and the electric motor unit, the rotary shaft being provided in a container; a first bearing provided on one end surface of the first cylinder and rotatably supporting the rotary shaft; a second bearing provided on one end surface of the second cylinder and rotatably supporting the rotary shaft; an intermediate partition plate provided between the other end surface of the first cylinder and the other end surface of the second cylinder that face each other, and separating the first compression chamber and the second compression chamber; a first small diameter bolt that is inserted through the first bearing and has a first male thread portion that is screwed into a first female thread portion formed in the first cylinder, and fastens the first bearing and the first cylinder together; a second small diameter bolt that is inserted through the second bearing and has a second male thread portion that is screwed into a second female thread portion formed on the second cylinder, and fastens the second bearing and the second cylinder together; a large-diameter bolt that is inserted into a first screw through-hole formed in the first cylinder and a second screw through-hole formed in the second cylinder, and fastens the first bearing, the first cylinder, the intermediate partition plate, the second cylinder, and the second bearing together; a diameter of the first male thread portion and a diameter of the second male thread portion are smaller than a diameter of the male thread portion of the large diameter bolt, a first discharge valve formed in the first bearing for opening and closing a first discharge hole through which the refrigerant compressed in the first compression chamber is discharged; a total of six bolts are provided in the circumferential direction around the axis of the first cylinder in the following order: the first small diameter bolt, the large diameter bolt, the large diameter bolt, the large diameter bolt, the first small diameter bolt, and the large diameter bolt; the first discharge hole is disposed between two of the three large diameter bolts disposed consecutively, The four large diameter bolts are arranged in different regions among the regions obtained by dividing the first cylinder into four equal parts by a line passing through the axis. Compressor.

2. a compression mechanism including a first cylinder having a first compression chamber therein and a second cylinder having a second compression chamber therein; an electric motor unit that drives the compression mechanism unit; a rotary shaft that connects the compression mechanism unit and the electric motor unit, the rotary shaft being provided in a container; a first bearing provided on one end surface of the first cylinder and rotatably supporting the rotary shaft; a second bearing provided on one end surface of the second cylinder and rotatably supporting the rotary shaft; an intermediate partition plate provided between the other end surface of the first cylinder and the other end surface of the second cylinder that face each other, and separating the first compression chamber and the second compression chamber; a first small diameter bolt that is inserted through the first bearing and has a first male thread portion that is screwed into a first female thread portion formed in the first cylinder, and fastens the first bearing and the first cylinder together; a second small diameter bolt that is inserted through the second bearing and has a second male thread portion that is screwed into a second female thread portion formed on the second cylinder, and fastens the second bearing and the second cylinder together; a large-diameter bolt that is inserted into a first screw through-hole formed in the first cylinder and a second screw through-hole formed in the second cylinder, and fastens the first bearing, the first cylinder, the intermediate partition plate, the second cylinder, and the second bearing together; a diameter of the first male thread portion and a diameter of the second male thread portion are smaller than a diameter of the male thread portion of the large diameter bolt, a first discharge valve formed in the first bearing for opening and closing a first discharge hole through which the refrigerant compressed in the first compression chamber is discharged; a total of five bolts are provided in the circumferential direction around the axis of the first cylinder in the following order: the first small diameter bolt, the large diameter bolt, the large diameter bolt, the first small diameter bolt, and the large diameter bolt; The first discharge hole is disposed between two successively disposed large diameter bolts, The three large diameter bolts are arranged in different regions among the regions obtained by dividing the first cylinder into four equal parts by a line passing through the axis. Compressor.

3. a compression mechanism including a first cylinder having a first compression chamber therein and a second cylinder having a second compression chamber therein; an electric motor unit that drives the compression mechanism unit; a rotary shaft that connects the compression mechanism unit and the electric motor unit, the rotary shaft being provided in a container; a first bearing provided on one end surface of the first cylinder and rotatably supporting the rotary shaft; a second bearing provided on one end surface of the second cylinder and rotatably supporting the rotary shaft; an intermediate partition plate provided between the other end surface of the first cylinder and the other end surface of the second cylinder that face each other, and separating the first compression chamber and the second compression chamber; a first small diameter bolt that is inserted through the first bearing and has a first male thread portion that is screwed into a first female thread portion formed in the first cylinder, and fastens the first bearing and the first cylinder together; a second small diameter bolt that is inserted through the second bearing and has a second male thread portion that is screwed into a second female thread portion formed on the second cylinder, and fastens the second bearing and the second cylinder together; a large-diameter bolt that is inserted into a first screw through-hole formed in the first cylinder and a second screw through-hole formed in the second cylinder, and fastens the first bearing, the first cylinder, the intermediate partition plate, the second cylinder, and the second bearing together; a diameter of the first male thread portion and a diameter of the second male thread portion are smaller than a diameter of the male thread portion of the large diameter bolt, a first discharge valve formed in the first bearing for opening and closing a first discharge hole through which the refrigerant compressed in the first compression chamber is discharged; a total of four bolts are provided in the circumferential direction around the axis of the first cylinder in the order of the first small diameter bolt, the large diameter bolt, the first small diameter bolt, and the large diameter bolt, The two large diameter bolts are arranged in different regions among the regions obtained by dividing the first cylinder into four equal parts by a line passing through the axis. Compressor.

4. The diameter of the first male screw portion and the diameter of the second male screw portion are the same. The compressor according to any one of claims 1 to 3.

5. a third female screw portion is formed in one of the first bearing and the second bearing, The male threaded portion of the large diameter bolt is screwed into the third female threaded portion, thereby fastening and fixing the first bearing, the first cylinder, the intermediate partition plate, the second cylinder, and the second bearing. The compressor according to any one of claims 1 to 3.

6. a nut having a third female screw portion formed thereon; The male threaded portion of the large diameter bolt is screwed into the third female threaded portion, thereby fastening and fixing the first bearing, the first cylinder, the intermediate partition plate, the second cylinder, and the second bearing. The compressor according to any one of claims 1 to 3.

7. A second discharge valve is provided which opens and closes a second discharge hole formed in the second bearing and discharges the refrigerant compressed in the second compression chamber; The first discharge valve and the second discharge valve are disposed so as to face each other in the axial direction. The compressor according to any one of claims 1 to 3.

8. a first discharge muffler that suppresses noise generated when the refrigerant is discharged from the first discharge hole; The first discharge muffler, the first bearing, and the first cylinder are fastened and fixed by the first small diameter bolt and the first female thread portion. The compressor according to any one of claims 1 to 3.

9. a second discharge muffler that suppresses noise generated when the refrigerant is discharged from the second discharge hole; The second discharge muffler, the second bearing, and the second cylinder are fastened and fixed by the second small diameter bolt and the second female thread portion. The compressor according to claim 7.

10. A compressor comprising the compressor according to any one of claims 1 to 3, an outdoor heat exchanger, a throttling device, and an indoor heat exchanger. Refrigeration cycle equipment.