Compressor and refrigeration cycle device

Abstract

A compressor (2) according to the present disclosure comprises: a sealed container (14); an electric motor (15); a low-stage compression mechanism unit (29) and a high-stage compression mechanism unit (30); and an intermediate partition plate (31), wherein the high-stage compression mechanism unit (30) is provided with a cylindrical high-stage cylinder block (40b), a high-stage rotation piston (41b), a high-stage vane (43b) that, together with the high-stage rotation piston (41b), divides an internal space of the high-stage cylinder block (40b) into a high-stage suction chamber (59b) and a high-stage compression chamber (60b), and a high-stage refrigerant supply path (58b) that is a space surrounded by a high-stage bearing (42b) and a high-stage discharge muffler (57b) and discharges a compressed refrigerant to an external space of the sealed container (14), and a high-stage back pressure chamber (70b), which is a space surrounded by the high-stage cylinder block (40b), the high-stage bearing (42b), the intermediate partition plate (31), and the high-stage vane (43b), differs from the internal space of the sealed container (14) and communicates with the high-stage refrigerant supply path (58b).

Description

[Technical Field]

[0001] The present disclosure relates to a compressor and a refrigeration cycle device. [Background technology]

[0002] Generally, a two-stage compressor is known that has a low-stage compression mechanism that compresses a refrigerant from low pressure to an intermediate pressure, and a high-stage compression mechanism that compresses the refrigerant from the intermediate pressure to a high pressure. Furthermore, a compressor that uses a vane mechanism (described later) in the compression mechanism section is known because it has high compression efficiency and is inexpensive.

[0003] For example, Patent Document 1 discloses a two-stage compressor having a low-stage compression mechanism and a high-stage compression mechanism to which a vane mechanism is applied.

[0004] In the two-stage compressor described in Patent Document 1, a low-stage compression mechanism supplies an intermediate-pressure refrigerant to a high-stage compression mechanism, which then discharges a high-pressure refrigerant to the outside of the sealed container via the internal space of the sealed container. The high-pressure refrigerant discharged into the internal space of the sealed container pressurizes the lubricating oil stored at the bottom of the sealed container, causing the lubricating oil to become highly pressurized.

[0005] Each compression mechanism includes a cylindrical cylinder, a cylindrical rotary piston disposed in the internal space of the cylinder, and a vane disposed in the cylinder and slidable in the radial direction of the cylinder. The cylinder has a vane back pressure chamber formed therein that communicates with the lubricating oil via a connecting passage.

[0006] The vane is pressed against the rotary piston by a spring provided in the vane back pressure chamber, and together with the rotary piston, divides the internal space of the cylinder into two spaces. The low-stage compression mechanism and the high-stage compression mechanism change the volumes of the two spaces to compress the refrigerant from low pressure to intermediate pressure and from intermediate pressure to high pressure, respectively. With this configuration, in the two-stage compressor described in Patent Document 1, the internal space of the cylinder provided in the high-stage compression mechanism is filled with high-pressure refrigerant, and the vane back pressure chamber is filled with high-pressure lubricating oil. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] WO2012 / 090345 publication Summary of the Invention [Problem to be solved by the invention]

[0008] However, when a configuration in which the vane back pressure chamber communicates with the lubricating oil via a connecting passage is applied to a two-stage compressor in which a low-stage compression mechanism supplies intermediate-pressure refrigerant to a high-stage compression mechanism via the internal space of a sealed container, the intermediate-pressure refrigerant released into the internal space of the sealed container pressurizes the lubricating oil stored at the bottom of the sealed container, causing the lubricating oil to be at an intermediate pressure. With this configuration, the internal space of the cylinder provided in the high-stage compression mechanism is filled with high-pressure refrigerant, and the vane back pressure chamber is filled with intermediate-pressure lubricating oil. This creates a pressure difference between the vane back pressure chamber and the internal space of the cylinder, which generates a force on the vane in a direction from the internal space of the cylinder toward the vane back pressure chamber, making it more likely to separate from the rotating piston. This results in poor contact between the vane and the rotating piston.

[0009] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a two-stage compressor that can suppress poor contact between the vanes and the rotating piston. [Means for solving the problem]

[0010] The compressor according to the present disclosure comprises a sealed container, and in the internal space of the sealed container, a low-stage compression mechanism unit that is driven by an electric motor and a crankshaft attached to the electric motor and compresses a refrigerant from a low pressure to an intermediate pressure, a high-stage compression mechanism unit that is driven by the crankshaft and compresses the refrigerant discharged from the low-stage compression mechanism unit from an intermediate pressure to a high pressure, and an intermediate partition plate provided between the low-stage compression mechanism unit and the high-stage compression mechanism unit, and the high-stage compression mechanism unit comprises a cylindrical high-stage cylinder block, a high-stage rotary piston that is arranged in the internal space of the high-stage cylinder block, and a rotary piston that is arranged slidably in the radial direction of the high-stage cylinder block and that, together with the high-stage rotary piston, circulates the internal space of the high-stage cylinder block. a high-stage vane separating the high-stage cylinder block into a high-stage suction chamber for sucking in a refrigerant and a high-stage compression chamber for compressing the refrigerant; a high-stage bearing supporting a crankshaft and adjacent to the high-stage cylinder block in the axial direction of the high-stage cylinder block; and a high-stage discharge muffler adjacent to the high-stage bearing in the axial direction of the high-stage cylinder block, the high-stage refrigerant supply passage being a path for discharging the refrigerant compressed in the high-stage compression chamber into an external space of the sealed container; the high-stage cylinder block comprising a high-stage back pressure chamber which is a space surrounded by the outer peripheral surface of the high-stage cylinder block, the high-stage bearing, the intermediate partition plate, and the high-stage vane; the high-stage back pressure chamber being a space different from the internal space of the sealed container and communicating with the high-stage refrigerant supply passage; The low-stage compression mechanism comprises a cylindrical low-stage cylinder block, a low-stage rotary piston arranged in the internal space of the low-stage cylinder block, and a low-stage vane arranged to slide freely radially of the low-stage cylinder block and, together with the low-stage rotary piston, divides the internal space of the low-stage cylinder block into a low-stage suction chamber that expands its volume to draw in refrigerant and a low-stage compression chamber that compresses the refrigerant by reducing its volume. The low-stage cylinder block comprises a low-stage backpressure chamber which is a space surrounded by the outer peripheral surface of the low-stage cylinder block, a low-stage bearing that supports the crankshaft and is adjacent to the low-stage cylinder block in the axial direction of the low-stage cylinder block, an intermediate partition plate, and the low-stage vane. The low-stage backpressure chamber is a space different from the internal space of the sealed container and is connected to the high-stage refrigerant supply passage without passing through the internal space of the sealed container.

[0011] The refrigeration cycle device according to the present disclosure includes a sealed container, and in the internal space of the sealed container, a low-stage compression mechanism unit that is driven by an electric motor and a crankshaft attached to the electric motor and compresses a refrigerant from a low pressure to an intermediate pressure, a high-stage compression mechanism unit that is driven by the crankshaft and compresses a refrigerant discharged from the low-stage compression mechanism unit from an intermediate pressure to a high pressure, and an intermediate partition plate provided between the low-stage compression mechanism unit and the high-stage compression mechanism unit, and the high-stage compression mechanism unit includes a cylindrical high-stage cylinder block, a high-stage rotary piston that is arranged in the internal space of the high-stage cylinder block, and a partition plate that is arranged slidably in the radial direction of the high-stage cylinder block and that, together with the high-stage rotary piston, a high-stage vane that divides the high-stage cylinder block into a high-stage suction chamber that draws in a refrigerant and a high-stage compression chamber that compresses the refrigerant, a high-stage bearing that supports the crankshaft and is adjacent to the high-stage cylinder block in the axial direction of the high-stage cylinder block, and a high-stage discharge muffler that is adjacent to the high-stage bearing in the axial direction of the high-stage cylinder block, and a high-stage refrigerant supply passage that is a path for discharging the refrigerant compressed in the high-stage compression chamber into an external space of the sealed container; the high-stage cylinder block has a high-stage back pressure chamber that is a space surrounded by the outer peripheral surface of the high-stage cylinder block, the high-stage bearing, the intermediate partition plate, and the high-stage vane, and the high-stage back pressure chamber is a space different from the internal space of the sealed container and is in communication with the high-stage refrigerant supply passage; The low-stage compression mechanism comprises a cylindrical low-stage cylinder block, a low-stage rotary piston arranged in the internal space of the low-stage cylinder block, and a low-stage vane arranged to slide freely in the radial direction of the low-stage cylinder block and, together with the low-stage rotary piston, divides the internal space of the low-stage cylinder block into a low-stage suction chamber that expands its volume to draw in refrigerant and a low-stage compression chamber that compresses the refrigerant by reducing its volume. The low-stage cylinder block comprises a low-stage backpressure chamber, which is a space surrounded by the outer peripheral surface of the low-stage cylinder block, a low-stage bearing that supports the crankshaft and is adjacent to the low-stage cylinder block in the axial direction of the low-stage cylinder block, an intermediate partition plate, and the low-stage vane. The low-stage backpressure chamber is a space different from the internal space of the sealed container and communicates with the high-stage refrigerant supply passage without passing through the internal space of the sealed container. The system comprises a compressor, a condenser that liquefies the refrigerant discharged from the compressor, a pressure reducing device that reduces the pressure of the refrigerant sent out from the condenser, and an evaporator that vaporizes the refrigerant sent out from the pressure reducing device.The system comprises a condenser that liquefies the fluid, a pressure reducing device that reduces the pressure of the compressed fluid, and an evaporator that vaporizes the fluid. [Effects of the Invention]

[0012] According to the present disclosure, poor contact between the vane and the rotary piston can be suppressed. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a diagram showing a refrigeration cycle device according to a first embodiment. [Figure 2] 1 is a vertical cross-sectional view of a compressor according to a first embodiment. [Figure 3]3A and 3B are schematic diagrams of a cross section taken along line AA and a cross section taken along line BB in FIG. 2. [Figure 4] 4 is a cross-sectional view taken along CC in FIG. 3. [Figure 5] FIG. 4 is a cross-sectional view taken along the line DD in FIG. 3. [Figure 6] FIG. 1 is a diagram showing the flow of refrigerant when the compressor is operating. [Figure 7] 4 is a diagram showing the flow of refrigerant when the compressor according to the first embodiment is operating. FIG. [Figure 8] FIG. 8 is a schematic diagram of an E-E cross section of FIG. 7. [Figure 9] FIG. 8 is a schematic diagram of the FF cross section of FIG. 7. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. Note that the drawings are schematic, and the relative sizes and positions shown in different drawings are not necessarily accurately depicted and may be changed as appropriate. In the following description, similar components are denoted by the same reference numerals, and their names and functions are assumed to be the same or similar. Therefore, detailed descriptions thereof may be omitted.

[0015] Embodiment 1

[0016] A refrigeration cycle apparatus 1 in this embodiment will be described with reference to Fig. 1. The refrigeration cycle apparatus 1 includes a compressor 2, a high-pressure side heat exchanger 3, a pressure reducing device 4, a low-pressure side heat exchanger 5, refrigerant piping 6, and a control unit (not shown).

[0017] The compressor 2, high-pressure side heat exchanger 3, pressure reduction device 4, and low-pressure side heat exchanger 5 are connected by refrigerant piping 6 to form a refrigeration cycle, in which the refrigerant circulates through the compressor 2, high-pressure side heat exchanger 3, pressure reduction device 4, and low-pressure side heat exchanger 5 in that order.

[0018] The refrigerant piping 6 includes a low-pressure refrigerant piping 7 that connects the low-pressure side heat exchanger 5 and the refrigerant suction pipe 10 and through which a low-pressure refrigerant flows, an intermediate-pressure refrigerant piping 8 that connects the refrigerant discharge pipe 12 and the refrigerant suction pipe 11 and through which an intermediate-pressure refrigerant flows, and a high-pressure refrigerant piping 9 that connects the refrigerant discharge pipe 13 and the high-pressure side heat exchanger 3 and through which a high-pressure refrigerant flows.

[0019] The compressor 2 compresses the refrigerant drawn in through the refrigerant suction pipe 10 to an intermediate pressure, discharges the compressed refrigerant from the refrigerant discharge pipe 12, and draws the refrigerant into the refrigerant suction pipe 11 via the intermediate-pressure refrigerant piping 8. The compressor 2 then compresses the refrigerant drawn in through the refrigerant suction pipe 11 to a high pressure, and discharges the compressed refrigerant from the refrigerant discharge pipe 13.

[0020] The high-pressure side heat exchanger 3 functions as a condenser, and performs heat exchange between the refrigerant compressed by the compressor 2 and air, thereby dissipating heat from the compressed refrigerant and liquefying the refrigerant. The pressure reducing device 4 expands the refrigerant that has dissipated heat in the high-pressure side heat exchanger 3. The low-pressure side heat exchanger 5 functions as an evaporator, and performs heat exchange between the refrigerant expanded by the pressure reducing device 4 and air, thereby heating the expanded refrigerant and vaporizing it.

[0021] The control unit controls the flow of the refrigerant by controlling the entire refrigeration cycle apparatus 1 based on instructions from an input device such as a remote control. The control unit, for example, controls the frequency of the compressor 2. The control unit is configured, for example, with an analog circuit, a digital circuit, a CPU (Central Processing Unit) and a memory, or a combination of two or more of these, and may be provided within the refrigeration cycle apparatus 1 or in a separate housing.

[0022] A description will be given of the operation of the refrigeration cycle device 1. Arrows shown in Fig. 1 indicate the direction of refrigerant flow. By driving the compressor 2, compressed refrigerant is discharged from the refrigerant discharge pipe 13 of the compressor 2. The refrigerant discharged from the compressor 2 flows into the high-pressure side heat exchanger 3. In the high-pressure side heat exchanger 3, heat is exchanged between the refrigerant that has flowed in and the air, causing the refrigerant to release heat. The refrigerant discharged from the high-pressure side heat exchanger 3 is expanded by the pressure reducing device 4. The refrigerant expanded by the pressure reducing device 4 flows into the low-pressure side heat exchanger 5. In the low-pressure side heat exchanger 5, heat is exchanged between the refrigerant that has flowed in and the air, heating the refrigerant. The refrigerant discharged from the low-pressure side heat exchanger 5 flows into the compressor 2, becomes compressed refrigerant, and is discharged from the compressor 2 again, repeating this cycle.

[0023] The refrigerant used may be at least one of HFC (HydroFluoroCarbon) refrigerants such as R32, R125, R134a, R407C, and R410A; HFO (HydroFluoroOlefin) refrigerants such as R1123, R1132(E), R1132(Z), R1132a, R1141, R1234yf, R1234ze(E), and R1234ze(Z); and natural refrigerants such as R290 (propane), R600a (isobutane), R744 (carbon dioxide), and R717 (ammonia).

[0024] The compressor 2 in this embodiment will be described with reference to FIGS. In the following description, the direction of the axes of the stator 25 and the rotor 26 indicated by A1 in Fig. 2 will be referred to as the "axial direction," and the radial direction around the axis indicated by arrow R1 will be referred to as the "radial direction." The compressor 2 includes a sealed container 14, an electric motor 15, a crankshaft 16, a low-stage compression mechanism 29, a high-stage compression mechanism 30, and an intermediate partition plate 31.

[0025] As shown in FIG. 2 , the sealed container 14 includes a cylindrical body 18, a hemispherical upper lid 19, and a hemispherical lower lid 20. The upper lid 19 is welded to the top of the body 18, and the lower lid 20 is welded to the bottom. The sealed container 14 is mounted on a base 21, to which the lower lid 20 is fixed. The sealed container 14 includes a refrigerant suction pipe 10 and a refrigerant suction pipe 11 for drawing in a refrigerant, and a refrigerant discharge pipe 12 and a refrigerant discharge pipe 13 for discharging the refrigerant. The top of the sealed container 14 includes a terminal 23 for connecting an external power source to a lead wire 22. The bottom of the sealed container 14 stores refrigerating machine oil 24 for lubricating the sliding parts of the low-stage compression mechanism 29 and the high-stage compression mechanism 30. The refrigerating machine oil 24 may be, for example, POE (polyol ester), PVE (polyvinyl ether), or AB (alkylbenzene).

[0026] The electric motor 15 includes a stator 25 and a rotor 26 that is coaxial with and has a certain gap with the stator 25. The electric motor 15 is located inside the body 18 and is installed on top of the low-stage compression mechanism 29 and the high-stage compression mechanism 30 by spot welding, shrink fitting, or the like, and drives the low-stage compression mechanism 29 and the high-stage compression mechanism 30 via the crankshaft 16.

[0027] The crankshaft 16 has a low-stage eccentric portion 27 that is eccentric in one direction and a high-stage eccentric portion 28 , and is attached to a rotor 26 .

[0028] The low-stage compression mechanism 29, the high-stage compression mechanism 30, and the intermediate partition plate 31 are stacked from the bottom up in the order of high-stage compression mechanism 30, intermediate partition plate 31, and low-stage compression mechanism 29.

[0029] The low-stage compression mechanism section 29 will be described with reference to Figures 2 to 5. Figure 3 is a part of a schematic diagram of the AA cross section in Figure 2, Figure 4 is an enlarged view of the low-stage compression mechanism section 29 and the high-stage compression mechanism section 30 in Figure 2 and a CC cross section in Figure 3, and Figure 5 is an enlarged view of the low-stage compression mechanism section 29 and the high-stage compression mechanism section 30 in Figure 2 and a DD cross section in Figure 3.

[0030] 2 and 3 includes a cylindrical low-stage cylinder block 40a, a cylindrical low-stage rotary piston 41a, a low-stage bearing 42a, a rectangular parallelepiped low-stage vane 43a, and a low-stage spring 44a, and compresses the refrigerant drawn through the refrigerant suction pipe 10 from low pressure to intermediate pressure and discharges it from the refrigerant discharge pipe 12. The low-stage cylinder block 40a and the low-stage bearing 42a are stacked in this order from the bottom up.

[0031] 3, the low-stage cylinder block 40a has, in its internal space, a low-stage cylinder chamber 45a coaxial with the crankshaft 16, a low-stage vane hole 46a in which a low-stage vane 43a is slidably disposed in the radial direction, a low-stage hole 47a that accommodates a low-stage spring 44a, a low-stage suction passage 49a through which refrigerant is drawn from the refrigerant suction pipe 10 via a low-stage suction communication passage 55a (described later), and a low-stage discharge passage 50a that discharges refrigerant to the refrigerant discharge pipe 12 via the internal space of the sealed container 14. Also, in FIG. 3, the low-stage cylinder block 40a is shown schematically, and a low-stage spring hole 48a, a low-stage female thread portion 51a, a low-stage plug 52a, and a low-stage male thread portion 53a (described later) are not shown.

[0032] The low-stage rotary piston 41 a is disposed in the low-stage cylinder chamber 45 a and is attached to the low-stage eccentric portion 27 of the crankshaft 16 .

[0033] The low-stage vane hole 46a is disposed between the low-stage suction passage 49a and the low-stage discharge passage 50a, and is formed radially from the low-stage cylinder chamber 45a toward the low-stage hole 47a, penetrating the low-stage cylinder block 40a in the axial direction.

[0034] The low-stage hole 47a is arranged between the low-stage suction path 49a and the low-stage discharge path 50a, and is formed between the low-stage vane hole 46a and the outer peripheral surface of the low-stage cylinder block 40a, penetrates the low-stage cylinder block 40a in the axial direction, and is connected to the low-stage vane hole 46a.

[0035] 3 is inserted into low-stage vane hole 46a so as to be slidable radially, and together with low-stage rotary piston 41a, divides low-stage cylinder chamber 45a into low-stage suction chamber 59a and low-stage compression chamber 60a. Note that the sliding surface of low-stage vane 43a may be coated with a coating such as DLC to reduce the coefficient of friction of the sliding surface.

[0036] The low-stage spring 44a is housed in the low-stage hole 47a and presses the low-stage vane 43a attached to the tip of the low-stage spring 44a against the outer circumferential surface of the low-stage rotary piston 41a.

[0037] The low-stage spring hole 48a, the low-stage female thread portion 51a, the low-stage plug 52a, and the low-stage male thread portion 53a will be described with reference to FIGS. The low-stage cylinder block 40a shown in FIG. 3 further includes a low-stage spring hole 48a for inserting the low-stage spring 44a shown in FIG. 4. The low-stage spring hole 48a is located between the low-stage suction passage 49a and the low-stage discharge passage 50a shown in FIG. 3, and is formed between the low-stage hole 47a and the outer peripheral surface of the low-stage cylinder block 40a. The low-stage spring hole 48a communicates with the outer peripheral surface of the low-stage cylinder block 40a, the low-stage hole 47a, and the low-stage vane hole 46a. As shown in FIG. 4, a low-stage female thread portion 51a, which is a female thread groove, is formed on the inner surface of the low-stage spring hole 48a. A low-stage plug 52a is disposed at the portion where the low-stage spring hole 48a contacts the outer peripheral surface of the low-stage cylinder block 40a to close the portion. A low-stage male thread portion 53a, which is a male thread groove, is formed on the outer surface of the low-stage plug 52a. A low-stage male thread portion 53a of the low-stage plug 52a is screwed into the low-stage female thread portion 51a, thereby separating a low-stage back pressure chamber 70a (to be described later) from the internal space of the sealed container 14.

[0038] In the low-stage compression mechanism section 29, a low-stage back pressure chamber 70a is formed by the outer peripheral surface of the low-stage cylinder block 40a, the lower surface of the low-stage bearing 42a, the upper surface of the intermediate partition plate 31, and the side surface of the low-stage vane 43a facing the outer peripheral surface.

[0039] The low-stage bearing 42a shown in Figures 4 and 5 supports the crankshaft 16. The low-stage bearing 42a also has a low-stage suction hole 54a into which the tip of the refrigerant suction pipe 10 is inserted, a low-stage suction communication passage 55a that connects the low-stage suction hole 54a to the low-stage suction passage 49a, and a first low-stage through-hole 56a (described later) that connects the low-stage discharge passage 50a to the low-stage refrigerant supply passage 58a. A low-stage discharge muffler 57a is disposed above the low-stage bearing 42a. The first low-stage through-hole 56a is not shown in Figure 4, which is the cross-sectional view taken along CC in Figure 3, or Figure 5, which is the cross-sectional view taken along DD in Figure 3, but is shown in Figure 8 (described later).

[0040] The low-stage refrigerant supply passage 58a is a space surrounded by the upper surface of the low-stage bearing 42a and the low-stage discharge muffler 57a, and is a path for discharging intermediate-pressure refrigerant compressed in the low-stage cylinder block 40a to the refrigerant discharge pipe 12.

[0041] The high-stage compression mechanism section 30 will be described with reference to Figures 2 to 5. Figure 3 is a part of a schematic diagram of the cross section BB in Figure 2, Figure 4 is an enlarged view of the low-stage compression mechanism section 29 and the high-stage compression mechanism section 30 in Figure 2 and a cross section CC in Figure 3, and Figure 5 is an enlarged view of the low-stage compression mechanism section 29 and the high-stage compression mechanism section 30 in Figure 2 and a cross section DD in Figure 3.

[0042] 2 and 3 includes a cylindrical high-stage cylinder block 40b, a cylindrical high-stage rotary piston 41b, a high-stage bearing 42b, a rectangular parallelepiped high-stage vane 43b, and a high-stage spring 44b, and compresses the refrigerant drawn through the refrigerant suction pipe 11 from an intermediate pressure to a high pressure, and discharges it from the refrigerant discharge pipe 13. The high-stage bearing 42b and the high-stage cylinder block 40b are stacked in this order from the bottom up.

[0043] 3, the high-stage cylinder block 40b has, in its internal space, a high-stage cylinder chamber 45b coaxial with the crankshaft 16, a high-stage vane hole 46b in which a high-stage vane 43b is slidably disposed in the radial direction, a high-stage hole 47b that accommodates a high-stage spring 44b, a high-stage suction passage 49b through which refrigerant is drawn from the refrigerant suction pipe 11 via a high-stage suction communication passage 55b (described later), and a high-stage discharge passage 50b that discharges refrigerant to the refrigerant discharge pipe 13 without passing through the internal space of the sealed container 14. Also, in FIG. 3, the high-stage cylinder block 40b is shown schematically, and a high-stage spring hole 48b, a high-stage female thread portion 51b, a high-stage plug 52b, and a high-stage male thread portion 53b (described later) are not shown.

[0044] The high-stage rotary piston 41 b is disposed in the high-stage cylinder chamber 45 b and is attached to the high-stage eccentric portion 28 of the crankshaft 16 .

[0045] The high-stage vane hole 46b is disposed between the high-stage suction passage 49b and the high-stage discharge passage 50b, and is formed radially from the high-stage cylinder chamber 45b toward the high-stage hole 47b, penetrating the high-stage cylinder block 40b in the axial direction.

[0046] The high-stage hole 47b is arranged between the high-stage suction path 49b and the high-stage discharge path 50b, and is formed between the high-stage vane hole 46b and the outer surface of the high-stage cylinder block 40b, axially penetrating the high-stage cylinder block 40b and communicating with the high-stage vane hole 46b.

[0047] 3 is inserted into high-stage vane hole 46b so as to be slidable in the radial direction, and, together with high-stage rotary piston 41b, divides high-stage cylinder chamber 45b into high-stage suction chamber 59b and high-stage compression chamber 60b. Note that the sliding surface of high-stage vane 43b may be coated with a coating such as DLC to reduce the coefficient of friction of the sliding surface.

[0048] The high-stage spring 44b is housed in the high-stage hole 47b and presses the high-stage vane 43b attached to the tip of the high-stage spring 44b against the outer circumferential surface of the high-stage rotary piston 41b.

[0049] The high-stage spring hole 48b, the high-stage female thread portion 51b, the high-stage plug 52b, and the high-stage male thread portion 53b will be described with reference to FIGS. The high-stage cylinder block 40b shown in FIG. 3 further includes a high-stage spring hole 48b for inserting the high-stage spring 44b shown in FIG. 4. The high-stage spring hole 48b is disposed between the high-stage suction passage 49b and the high-stage discharge passage 50b shown in FIG. 3, and is formed between the high-stage hole 47b and the outer peripheral surface of the high-stage cylinder block 40b. The high-stage spring hole 48b communicates with the outer peripheral surface of the high-stage cylinder block 40b, the high-stage hole 47b, and the high-stage vane hole 46b. As shown in FIG. 4, a high-stage female thread portion 51b, which is a female thread groove, is formed on the inner surface of the high-stage spring hole 48b. A high-stage plug 52b is disposed at the portion where the high-stage spring hole 48b contacts the outer peripheral surface of the high-stage cylinder block 40b to close the portion. A high-stage male thread portion 53b, which is a male thread groove, is formed on the outer surface of the high-stage plug 52b. The high-stage male thread portion 53b of the high-stage plug 52b is screwed into the high-stage female thread portion 51b, thereby separating the high-stage back pressure chamber 70b (described later) from the internal space of the sealed container 14.

[0050] In the high-stage compression mechanism section 30, a high-stage back pressure chamber 70b is formed by the outer peripheral surface of the high-stage cylinder block 40b, the upper surface of the high-stage bearing 42b, the lower surface of the intermediate partition plate 31, and the side surface of the high-stage vane 43b facing the outer peripheral surface.

[0051] The high-stage bearing 42b shown in Figures 4 and 5 supports the crankshaft 16. The high-stage bearing 42b also includes a high-stage suction hole 54b into which the tip of the refrigerant suction pipe 11 is inserted, a high-stage suction communication passage 55b that connects the high-stage suction hole 54b to the high-stage suction passage 49b, a first high-stage through-hole 56b (described later) that connects the high-stage discharge passage 50b to the high-stage refrigerant supply passage 58b, and a second high-stage through-hole 61b that connects the high-stage backpressure chamber 70b to the high-stage refrigerant supply passage 58b. A high-stage discharge muffler 57b is disposed below the high-stage bearing 42b. The first high-stage through-hole 56b is not shown in Figure 4, which is the cross-sectional view taken along CC in Figure 3, or Figure 5, which is the cross-sectional view taken along DD in Figure 3, but is shown in Figure 9, which will be described later.

[0052] The high-stage refrigerant supply passage 58b is a space surrounded by the underside of the high-stage bearing 42b and the high-stage discharge muffler 57b, and is a path for discharging high-pressure refrigerant compressed in the high-stage cylinder block 40b to the refrigerant discharge pipe 13.

[0053] The intermediate partition plate 31 is disposed between the low-stage cylinder block 40a and the high-stage cylinder block 40b, and separates the low-stage cylinder chamber 45a and the high-stage cylinder chamber 45b into different spaces. The intermediate partition plate 31 is formed with a second low-stage through-hole 61a that connects the low-stage back pressure chamber 70a and the high-stage refrigerant supply passage 58b.

[0054] The operation of the compressor 2 will be described with reference to Figures 6 to 9. Here, Figure 7 is an enlarged view of the low-stage compression mechanism section 29 and the high-stage compression mechanism section 30 in Figure 6, the left half from the axis A1 in Figure 7 is a cross-sectional view taken along line CC in Figure 3, the right half from the axis A1 in Figure 7 is a cross-sectional view taken along line DD in Figure 3, Figure 8 is a schematic view of the cross-sectional view taken along line EE in Figure 7, and Figure 9 is a schematic view of the cross-sectional view taken along line FF in Figure 7. Arrows (1) to (11) shown in Figures 6 to 9 indicate the direction of refrigerant flow.

[0055] First, by supplying power from terminal 23 to electric motor 15 via lead wire 22, crankshaft 16 attached to rotor 26 rotates, causing low-stage rotary piston 41a to rotate eccentrically in low-stage cylinder chamber 45a. The volumes of the two spaces divided into low-stage suction chamber 59a and low-stage compression chamber 60a by low-stage rotary piston 41a and low-stage vane 43a change. As the volume of low-stage suction chamber 59a gradually expands, low-pressure refrigerant is drawn into low-stage suction path 49a via low-pressure refrigerant piping 7, refrigerant suction pipe 10, and low-stage suction communication path 55a, as shown by arrows (1) and (2) in FIG. 6. In the low-stage compression chamber 60a, the volume gradually decreases, compressing the sucked low-pressure refrigerant, and the intermediate-pressure refrigerant is discharged into the sealed container 14 via the low-stage discharge path 50a, the first low-stage through-hole 56a, the low-stage refrigerant supply path 58a, and the low-stage discharge muffler 57a, as shown by arrows (3) and (4) in Figures 6 and 8.

[0056] Here, the first low-step through-hole 56a will be described in detail with reference to FIGS. 8 is provided in the low-stage bearing 42a to communicate between the low-stage discharge path 50a and the low-stage refrigerant supply path 58a. By providing the first low-stage through-hole 56a, the refrigerant flows from the low-stage discharge path 50a to the low-stage refrigerant supply path 58a, as shown by the arrow (3) in FIG. 6. Then, as shown by the arrow (4) in FIG. 6, the refrigerant is supplied to the low-stage refrigerant supply path 58a and is discharged from the low-stage discharge muffler 57a into the internal space of the sealed container 14. Arrow (3) in FIG. 8 shows the state of the refrigerant flow indicated by arrow (3) in FIG. 6 after passing through first low-stage through-hole 56a in low-stage refrigerant supply passage 58a.

[0057] Then, as shown by arrows (5) and (6) in Figure 6, the intermediate-pressure refrigerant discharged into the sealed container 14 is discharged from the refrigerant discharge pipe 12, passes through the intermediate-pressure refrigerant piping 8, and is sucked into the refrigerant suction pipe 11.

[0058] Similarly to the low-stage compression mechanism 29, the high-stage rotary piston 41b rotates eccentrically in the high-stage cylinder chamber 45b. The high-stage rotary piston 41b and the high-stage vane 43b divide the two spaces into a high-stage suction chamber 59b and a high-stage compression chamber 60b, changing their volumes. As the volume of the high-stage suction chamber 59b gradually increases, intermediate-pressure refrigerant is drawn from the high-stage suction passage 49b via the intermediate-pressure refrigerant piping 8, the refrigerant suction pipe 11, and the high-stage suction communication passage 55b, as indicated by arrows (6) and (7) in FIG. 6. As the volume of the high-stage compression chamber 60b gradually decreases, the drawn intermediate-pressure refrigerant is compressed, and high-pressure refrigerant is discharged from the refrigerant discharge pipe 13 via the high-stage discharge passage 50b, the first high-stage through-hole 56b, the high-stage refrigerant supply passage 58b, and the high-stage discharge muffler 57b, as indicated by arrows (8) and (9) in FIG. 6 and FIG. 9. At the same time, the high-pressure refrigerant discharged into the high-stage discharge muffler 57b is supplied to the high-stage back pressure chamber 70b via the second high-stage through-hole 61b as shown by arrow (10) in Figures 7 and 9, and then supplied to the low-stage back pressure chamber 70a via the second low-stage through-hole 61a as shown by arrow (11) in Figure 7.

[0059] Here, the first high-stage through-hole 56b and the second high-stage through-hole 61b will be described in detail with reference to FIGS. 9 is provided in the high-stage bearing 42b to communicate between the high-stage discharge passage 50b and the high-stage refrigerant supply passage 58b. By providing the first high-stage through-hole 56b, the refrigerant flows from the high-stage discharge passage 50b to the high-stage refrigerant supply passage 58b, as shown by the arrow (8) in FIG. 6. Then, as shown by the arrow (9) in FIG. 6, the refrigerant is supplied to the high-stage refrigerant supply passage 58b, and high-pressure refrigerant is discharged from the high-stage discharge muffler 57b and the refrigerant discharge pipe 13. Arrow (8) in Figure 9 shows the refrigerant flow indicated by arrow (8) in Figure 6 after it has passed through the first high-stage through hole 56b in the high-stage refrigerant supply passage 58b, and arrow (10) in Figure 9 shows the refrigerant flow indicated by arrow (10) in Figure 7 before it passes through the second high-stage through hole 61b in the high-stage refrigerant supply passage 58b.

[0060] In the compressor 2 of this embodiment, high-pressure refrigerant discharged into the high-stage discharge muffler 57b is supplied to the high-stage backpressure chamber 70b via the second high-stage through-hole 61b, and then to the low-stage backpressure chamber 70a via the second low-stage through-hole 61a. In the low-stage compression mechanism 29, the low-stage backpressure chamber 70a is filled with high-pressure refrigerant, and the low-stage suction chamber 59a and the low-stage compression chamber 60a are filled with low-pressure refrigerant and intermediate-pressure refrigerant, respectively. This results in a refrigerant pressure relationship between the low-stage backpressure chamber 70a and the low-stage cylinder chamber 45a such that the low-stage backpressure chamber 70a is greater than the low-stage cylinder chamber 45a. This prevents a force acting on the low-stage vane 43a in a direction from the low-stage cylinder chamber 45a toward the low-stage backpressure chamber 70a, preventing the low-stage vane 43a from separating from the low-stage rotary piston 41a. As a result, poor contact between the low-stage vane 43a and the low-stage rotary piston 41a can be suppressed.

[0061] Furthermore, by suppressing poor contact between the low-stage vane 43a and the low-stage rotary piston 41a, the low-stage vane 43a can better follow the low-stage rotary piston 41a, thereby suppressing poor refrigerant compression caused by insufficient partitioning between the low-stage suction chamber 59a and the low-stage compression chamber 60a.

[0062] In addition, when the low-stage vane 43a has low ability to follow the low-stage rotary piston 41a, the low-stage vane 43a and the low-stage rotary piston 41a repeatedly separate and come into contact with each other, which generates noise caused by the collision sound between the low-stage vane 43a and the low-stage rotary piston 41a, and this can be suppressed.

[0063] In the high-stage compression mechanism 30, the high-stage backpressure chamber 70b is filled with high-pressure refrigerant, and the high-stage suction chamber 59b and the high-stage compression chamber 60b are filled with intermediate-pressure refrigerant and high-pressure refrigerant, respectively. This establishes a pressure relationship between the high-stage backpressure chamber 70b and the high-stage cylinder chamber 45b such that the high-stage backpressure chamber 70b is greater than or equal to the high-stage cylinder chamber 45b. This prevents a force acting on the high-stage vane 43b in a direction from the high-stage cylinder chamber 45b toward the high-stage backpressure chamber 70b, thereby preventing the high-stage vane 43b from separating from the high-stage rotary piston 41b. This effectively prevents poor contact between the high-stage vane 43b and the high-stage rotary piston 41b.

[0064] Furthermore, by suppressing poor contact between the high-stage vane 43b and the high-stage rotary piston 41b, the high-stage vane 43b can better follow the high-stage rotary piston 41b, thereby suppressing poor refrigerant compression caused by insufficient partitioning between the high-stage suction chamber 59b and the high-stage compression chamber 60b.

[0065] Furthermore, if the high-stage vane 43b has high tracking ability with the high-stage rotary piston 41b, the noise caused by the collision sound between the high-stage vane 43b and the high-stage rotary piston 41b, which occurs as the high-stage vane 43b and the high-stage rotary piston 41b repeatedly separate and come into contact with each other, can be suppressed.

[0066] In this embodiment, an example is shown in which the low-stage compression mechanism unit 29 is arranged in the upper stage and the high-stage compression mechanism unit 30 is arranged in the lower stage, but the low-stage compression mechanism unit 29 may also be arranged in the lower stage and the high-stage compression mechanism unit 30 in the upper stage.

[0067] In this embodiment, an example has been shown in which the low-stage male thread portion 53a of the low-stage plug 52a is screwed into the low-stage female thread portion 51a, thereby separating the low-stage back pressure chamber 70a from the interior of the sealed container 14, and the high-stage male thread portion 53b of the high-stage plug 52b is screwed into the high-stage female thread portion 51b, thereby separating the high-stage back pressure chamber 70b from the interior of the sealed container 14, but the low-stage spring hole 48a and the low-stage plug 52a, and the high-stage spring hole 48b and the high-stage plug 52b may each be joined by welding or the like.

[0068] In the above-described embodiments, the materials, materials, dimensions, shapes, relative positions, and implementation conditions of each component may be described. However, these are merely examples in all respects and are not intended to limit the scope of each embodiment. Therefore, countless variations not exemplified are contemplated within the scope of each embodiment. For example, these include modifying, adding, or omitting any component, and even extracting at least one component from at least one embodiment and combining it with a component from another embodiment. [Explanation of symbols]

[0069] 1 Refrigeration cycle device, 2 Compressor, 3 High-pressure side heat exchanger, 4 Pressure reducing device, 5 Low-pressure side heat exchanger, 14 Sealed vessel, 15 Electric motor, 16 Crankshaft, 29 Low-stage compression mechanism, 30 High-stage compression mechanism, 40a Low-stage cylinder block, 40b High-stage cylinder block, 41a Low-stage rotating piston, 41b High-stage rotating piston, 42a Low-stage bearing, 42b High-stage bearing, 43a Low-stage vane, 43b High-stage vane, 48a Low-stage spring hole, 48b High-stage spring hole, 51a Low-stage female thread portion, 51b High-stage female thread portion, 52a Low-stage plug, 52b High-stage plug, 53a Low-stage male thread portion, 53b High-stage male thread portion, 57a Low-stage discharge muffler, 57b High-stage discharge muffler, 58a Low-stage refrigerant supply passage, 58b High-stage refrigerant supply passage, 59a low-stage suction chamber, 59b high-stage suction chamber, 60a low-stage compression chamber, 60b high-stage compression chamber, 61a second low-stage through-hole, 61b second high-stage through-hole, 70a low-stage back pressure chamber, 70b high-stage back pressure chamber

Claims

1. The compressor includes a sealed container, and in an internal space of the sealed container, a low-stage compression mechanism unit that is driven by an electric motor and a crankshaft attached to the electric motor and compresses a refrigerant from a low pressure to an intermediate pressure, a high-stage compression mechanism unit that is driven by the crankshaft and compresses a refrigerant discharged from the low-stage compression mechanism unit from an intermediate pressure to a high pressure, and an intermediate partition plate provided between the low-stage compression mechanism unit and the high-stage compression mechanism unit, The high-stage compression mechanism portion is A cylindrical high-stage cylinder block; a high-stage rotary piston disposed in the internal space of the high-stage cylinder block; a high-stage vane that is arranged slidably in the radial direction of the high-stage cylinder block and that, together with the high-stage rotary piston, divides the internal space of the high-stage cylinder block into a high-stage suction chamber that draws in a refrigerant and a high-stage compression chamber that compresses the refrigerant; a high-stage refrigerant supply passage, which is a space surrounded by a high-stage bearing supporting the crankshaft and adjacent to the high-stage cylinder block in the axial direction of the high-stage cylinder block, and a high-stage discharge muffler adjacent to the high-stage bearing in the axial direction of the high-stage cylinder block, and which is a path for discharging the refrigerant compressed in the high-stage compression chamber to an external space of the sealed container; Equipped with the high-stage cylinder block includes a high-stage back pressure chamber that is a space surrounded by an outer peripheral surface of the high-stage cylinder block, the high-stage bearing, the intermediate partition plate, and the high-stage vane, the high-stage back pressure chamber is a space different from the internal space of the sealed container and communicates with the high-stage refrigerant supply passage; The low-stage compression mechanism portion is A cylindrical low-stage cylinder block; a low-stage rotary piston disposed in the internal space of the low-stage cylinder block; a low-stage vane that is arranged slidably in the radial direction of the low-stage cylinder block and that, together with the low-stage rotary piston, divides the internal space of the low-stage cylinder block into a low-stage suction chamber that draws in a refrigerant by expanding its volume and a low-stage compression chamber that compresses the refrigerant by reducing its volume; Equipped with the low-stage cylinder block includes a low-stage back pressure chamber, which is a space surrounded by an outer peripheral surface of the low-stage cylinder block, a low-stage bearing that supports the crankshaft and is adjacent to the low-stage cylinder block in the axial direction of the low-stage cylinder block, the intermediate partition plate, and the low-stage vane; the low-stage back pressure chamber is a space different from the internal space of the sealed container and communicates with the high-stage refrigerant supply passage without passing through the internal space of the sealed container; Compressor.

2. The high-stage bearing has a high-stage through-hole formed therein, which connects the high-stage back pressure chamber and the high-stage refrigerant supply passage. The compressor according to claim 1 .

3. The intermediate partition plate has a low-stage through-hole formed therein, which connects the low-stage back pressure chamber and the high-stage refrigerant supply passage. The compressor according to claim 1 .

4. a high-stage spring hole formed in the high-stage cylinder block so that an outer peripheral surface of the high-stage cylinder block and the high-stage back pressure chamber communicate with each other; a high-stage plug provided at a portion where the high-stage spring hole contacts the outer peripheral surface of the high-stage cylinder block so as to close the high-stage spring hole; The compressor according to any one of claims 1 to 3, comprising:

5. A high-stage female screw portion is formed in the high-stage spring hole, The high-stage plug has a high-stage male screw portion formed therein, The high-stage plug is screwed into the high-stage spring hole. The compressor according to claim 4.

6. a low-stage spring hole formed in the low-stage cylinder block so that an outer peripheral surface of the low-stage cylinder block and the low-stage back pressure chamber communicate with each other; a low-stage plug provided at a portion where the low-stage spring hole contacts the outer peripheral surface of the low-stage cylinder block so as to close the low-stage spring hole; The compressor according to any one of claims 1 to 3, comprising:

7. A low-stage female screw portion is formed in the low-stage spring hole, The low-stage plug has a low-stage male screw portion formed therein, The low stage plug is screwed into the low stage spring hole. The compressor according to claim 6.

8. A compressor according to any one of claims 1 to 3; a condenser that liquefies the refrigerant discharged from the compressor; a pressure reducing device for reducing the pressure of the refrigerant sent out from the condenser; an evaporator that vaporizes the refrigerant sent from the pressure reducing device; Equipped with Refrigeration cycle equipment.

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