Rotary compressor and refrigeration cycle system

Abstract

Provided is a rotary compressor that can be made compact and that can prevent a drop in reliability of a multi-stage compression mechanism.　A compression mechanism (18) of a compressor (2) includes: a low pressure-side cylinder (55) having a low pressure-side compression chamber (61) that compresses an introduced gaseous refrigerant by the motive power of a low pressure-side eccentric part (51) and that discharges such refrigerant; a high pressure-side cylinder (57) that compresses the refrigerant discharged from the low pressure-side compression chamber (61) with the motive power of a high pressure-side eccentric part (52); and a partition plate (56) provided between the low pressure-side cylinder (55) and the high pressure-side cylinder (57). The height of the low pressure-side compression chamber (61) is the same as the height of the high pressure-side compression chamber (62), and the inner diameter dimension of the low pressure-side compression chamber (61) is greater than the inner diameter dimension of the high pressure-side compression chamber (62).

Description

Technical Field

[0001] Embodiments of the present invention relate to a rotary compressor and a refrigeration cycle apparatus.

Background Art

[0002] A rotary compressor including a vertically disposed cylindrical sealed container, a compression mechanism portion disposed at the lower part inside the sealed container, a motor as an electric motor portion disposed inside the sealed container and above the compression mechanism portion for driving the compression mechanism portion, and a rotating shaft is known. The rotating shaft extends along a center line extending vertically through the sealed container. The compression mechanism portion is connected to the motor via the rotating shaft. The compression mechanism portion compresses the refrigerant gas flowing in from the outside of the sealed container by the power of the rotating shaft.

[0003] The compression mechanism portion has a first compression chamber, an annular first roller fitted onto a first eccentric portion of the rotating shaft, a first blade partitioning an internal space of the first compression chamber, a second compression chamber connected to the first compression chamber, an annular second roller fitted onto a second eccentric portion of the rotating shaft, and a second blade partitioning an internal space of the second compression chamber. The first roller revolves along the inner wall surface of the first compression chamber, and the second roller revolves along the inner wall surface of the second compression chamber. The first compression chamber compresses and discharges the refrigerant gas flowing in from the outside by the revolution of the first roller. The discharged refrigerant gas is further compressed by the revolution of the second roller in the second compression chamber.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Here, the volume of space in which the roller moves during one rotation is called the discharge volume. In conventional rotary compressors, the discharge volume of the first compression chamber is set larger than the predetermined discharge volume of the second compression chamber in order to further increase the pressure of the refrigerant gas discharged from the first compression chamber in the second compression chamber and to pressurize a predetermined amount of refrigerant gas.

[0006] To increase the internal volume of the first cylinder related to the displacement volume of the first compression chamber, for example, the height of the first compression chamber is set to be greater than the height of the second compression chamber. The height of the first blade located in the first compression chamber is greater than the height of the second blade located in the second compression chamber.

[0007] However, if the height of the first compression chamber is greater than the height of the second compression chamber, the height of the first blade will be greater than the height of the second blade. Generally, increasing the height of the blades increases the load on the blades, for example from the refrigerant gas, which tends to reduce the reliability of the blades' operation. Also, making the height of the first compression chamber greater than the height of the second compression chamber encourages the enlargement of the compression mechanism, and consequently, the enlargement of the compressor.

[0008] Therefore, the present invention aims to provide a rotary compressor that prevents a decrease in the reliability of a multi-stage compression mechanism and can be miniaturized. [Means for solving the problem]

[0009] To solve the aforementioned problems, the rotary compressor according to the embodiment of the present invention has a center extending in the vertical direction line A sealed container having, and an electric motor unit provided inside the sealed container, low A pressure-side eccentric portion and a portion located below the low-pressure-side eccentric portion. Ta It has a high-pressure side eccentric portion, and the electric motor portion is the center lineThe compression mechanism comprises a crankshaft that is rotationally driven around a central axis, a low-pressure cylinder having a low-pressure compression chamber that compresses and discharges introduced gaseous refrigerant using the power of the low-pressure eccentric portion, a high-pressure cylinder having a high-pressure compression chamber that compresses the refrigerant discharged from the low-pressure compression chamber using the power of the high-pressure eccentric portion, and a partition plate provided between the low-pressure cylinder and the high-pressure cylinder, wherein the low-pressure eccentric portion is positioned eccentrically from the center line of the sealed container by a first eccentricity length at its center, the high-pressure eccentric portion is positioned eccentrically from the center line of the sealed container by a second eccentricity length different from the first eccentricity length at its center, the height of the low-pressure compression chamber is the same as the height of the high-pressure compression chamber, and the inner diameter of the low-pressure compression chamber is larger than the inner diameter of the high-pressure compression chamber. The partition plate and the high-pressure side cylinder have an intermediate-pressure passage, which connects the discharge section of the low-pressure side compression chamber and the suction section of the high-pressure side compression chamber. The partition plate has a first partition plate half and a second partition plate half superimposed below the first partition plate half, and a part of the intermediate-pressure passage is provided at the joint surface of the first partition plate half and the second partition plate half. The first partition plate half has a recess that opens to the lower surface of the first partition plate half and a hole that connects the recess to the low-pressure side compression chamber. The second partition plate half has a recess that opens to the upper surface of the second partition plate half. The partition plate is equipped with a first discharge valve that discharges the refrigerant compressed in the low-pressure side compression chamber into the intermediate-pressure passage. The first discharge valve is provided in the recess of the first partition plate half and opens and closes the hole. When the thickness of the bottom plate portion of the recess in the first partition plate half is t1, the thickness of the bottom plate portion of the recess in the second partition plate half is t2, and the thickness of the first partition plate half near the valve seat where the hole and the first discharge valve are located is t3, the rotary compressor satisfies the following relational expression (1). t3 ≤ t1 <t2 (1)

[0010] In the rotary compressor according to the embodiment of the present invention, the first eccentricity length is preferably greater than the second eccentricity length.

[0011] In an embodiment of the present invention, the compression start angle of the high-pressure side compression chamber of the rotary compressor is preferably greater than the compression start angle of the low-pressure side compression chamber.

[0012] In an embodiment of the present invention, the high-pressure side cylinder of the rotary compressor preferably has a groove provided on the wall surface that partitions the high-pressure side compression chamber and connected to the suction portion of the high-pressure side compression chamber.

[0013] The rotary compressor according to an embodiment of the present invention preferably satisfies the following relational expression (1'). t3 <t1<t2 (1′)

[0014] In a rotary compressor according to an embodiment of the present invention, it is preferable that the second partition plate half is thicker than the first partition plate half, and that the recess of the second partition plate half is more deeply recessed than the recess of the first partition plate half.

[0015] The rotary compressor according to an embodiment of the present invention includes an intermediate pipe provided outside the sealed container, and it is preferable that the medium-pressure flow path is connected to the suction portion of the high-pressure side compression chamber via the intermediate pipe.

[0016] In addition, in order to solve the above problems, a refrigeration cycle device according to an embodiment of the present invention includes the rotary compressor, a radiator, an expansion device, a heat absorber, and a refrigerant pipe that connects the rotary compressor, the radiator, the expansion device, and the heat absorber to circulate refrigerant.

Effect of the Invention

[0017] According to the present invention, it is possible to provide a rotary compressor that prevents a decrease in reliability of a multi-stage compression mechanism portion and enables miniaturization.

Brief Description of the Drawings

[0018] [Figure 1] Schematic diagrams of a refrigeration cycle device and a compressor according to an embodiment of the present invention. [Figure 2] A plan sectional view passing through the first cylinder of the compressor according to an embodiment of the present invention. [Figure 3] A plan sectional view passing through the second cylinder of the compressor according to an embodiment of the present invention. [Figure 4] A longitudinal sectional view of a partition plate of the compressor according to an embodiment of the present invention. [Figure 5] A longitudinal sectional view of another example of a partition plate of the compressor according to an embodiment of the present invention. [Figure 6] (a) is a sectional view taken along line B - B' shown in FIG. 3, and (b) is a partial sectional view taken along line D - D' shown in (a). [Figure 7] (a) is a sectional view showing a modified example of a groove in an embodiment of the present invention, and (b) is a partial sectional view taken along line E - E' shown in (a). [Figure 8] (a) is a sectional view showing a modified example of a groove in an embodiment of the present invention, and (b) is a partial sectional view taken along line F - F' shown in (a). [[ID=4!]] [Figure 9](a) is a cross-sectional view showing a modified example of the groove in an embodiment of the present invention, and (b) is a partial cross-sectional view of the line G-G' shown in (a). [Modes for carrying out the invention]

[0019] Embodiments of the compressor and refrigeration cycle device according to the present invention will be described with reference to Figures 1 to 6. Note that the same or corresponding components are denoted by the same reference numerals in multiple drawings.

[0020] Figure 1 is a schematic diagram of a refrigeration cycle device and compressor according to an embodiment of the present invention. In Figure 1, the compressor is shown in a longitudinal cross-section.

[0021] Figure 2 is a plan cross-sectional view passing over the first cylinder of a compressor according to an embodiment of the present invention.

[0022] Figure 3 is a plan cross-sectional view passing over the second cylinder of a compressor according to an embodiment of the present invention.

[0023] The refrigeration cycle device 1 according to this embodiment is, for example, an air conditioner. The refrigeration cycle device 1 includes a sealed rotary compressor 2 (hereinafter simply referred to as "compressor 2") that compresses a gaseous refrigerant, such as carbon dioxide (CO2), which is the working fluid; a heat exchanger 3 (condenser) that cools the high-temperature, high-pressure refrigerant discharged from the compressor 2; a first expansion device 4 (expansion valve) and a second expansion device 5 (expansion valve) that reduce the pressure of the cooled refrigerant; a heat absorber 6 (evaporator) that evaporates the reduced-pressure refrigerant; an accumulator 7 that separates the refrigerant into gas and liquid; a first refrigerant pipe 8; and a second refrigerant pipe 9.

[0024] The first refrigerant piping 8 sequentially connects the compressor 2, radiator 3, first expansion device 4, second expansion device 5, heat absorber 6, and accumulator 7 to circulate the refrigerant. The accumulator 7 has an outlet pipe 12 that is connected to the compressor 2 and allows the refrigerant to flow into the compressor 2. One end of the second refrigerant piping 9 is connected to the first refrigerant piping 8 between the first expansion device 4 and the second expansion device 5. The other end of the second refrigerant piping 9 is connected to the intermediate piping 13 of the compressor 2. The second refrigerant piping 9 allows the refrigerant, which has been reduced to, for example, an intermediate pressure in the first expansion device 4, to flow into the compressor 2 via the intermediate piping 13.

[0025] The compressor 2 comprises a vertically positioned cylindrical sealed container 16, an electric motor unit 17 housed in the upper half of the sealed container 16, a compression mechanism unit 18 housed in the lower half of the sealed container 16, a crankshaft 19 that transmits the rotational driving force of the electric motor unit 17 to the compression mechanism unit 18, a main bearing 21 provided below the electric motor unit 17 to rotatably support the crankshaft 19, a sub-bearing 22 provided below the main bearing 21 to rotatably support the crankshaft 19 in cooperation with the main bearing 21, a frame 23 fixed to the sealed container 16 to support the compression mechanism unit 18, and intermediate piping 13 provided on the outside of the sealed container 16.

[0026] The centerline of the vertically positioned sealed container 16 extends in the vertical direction. The compressor 2 is installed with the centerline of the sealed container 16 oriented vertically. The sealed container 16 comprises a cylindrical body 26 extending in the vertical direction, an upper end plate 27 that closes the upper end of the body 26, and a lower end plate 28 that closes the lower end of the body 26. The sealed container 16 stores lubricating oil for lubricating the compression mechanism 18. The lubricating oil is supplied to the compression mechanism 18 through an oil supply mechanism provided in the lower end of the crankshaft 19.

[0027] The upper end plate 27 of the sealed container 16 is equipped with a discharge pipe 31 that discharges the high-temperature, high-pressure refrigerant discharged from the compression mechanism 18 into the sealed container 16 to the outside of the sealed container 16. The discharge pipe 31 is connected to the first refrigerant piping 8. The upper end plate 27 is also equipped with a terminal block 32 having sealed terminals that conduct power from an external power source to the motor unit 17. The sealed terminals of the terminal block 32 are provided on both the outside and inside of the upper end plate 27.

[0028] The body 26 of the sealed container 16 includes a suction end 35 connected to the outlet pipe 12 of the accumulator 7, an intermediate discharge end 36 connected to one end of the intermediate piping 13, and an intermediate suction end 37 connected to the other end of the intermediate piping 13. The suction end 35, the intermediate discharge end 36, and the intermediate suction end 37 each have a central portion fixed to the sealed container 16, an inner end positioned inside the sealed container 16, and an outer end positioned outside the sealed container 16. The body 26 of the sealed container 16 is also provided with a fixing device 38, such as a holder, for fixing the accumulator 7 to the outer surface of the body 26.

[0029] The intermediate piping 13 circulates the refrigerant, which has been compressed to medium pressure by the compression mechanism 18, to the outside of the sealed container 16. The intermediate piping 13 is connected to the cylindrical external muffler 39 and the intercooler 41. The intermediate piping 13 circulates the refrigerant by sequentially connecting the intermediate discharge end 36, the external muffler 39, the intercooler 41, and the intermediate suction end 37. The external muffler 39 has a cylindrical shape extending in the vertical direction and is fixed to the outer surface of the sealed container 16 by fixing devices 38 such as holders provided on the body 26 of the sealed container 16. The intermediate piping 13 circulates the refrigerant, which has been compressed to medium pressure by the compression mechanism 18.

[0030] The motor unit 17 generates a driving force to rotate the compression mechanism unit 18. The motor unit 17 comprises a cylindrical stator 43 fixed to the inner surface of the sealed container 16, a rotor 44 positioned inside the stator 43 to generate the rotational driving force for the compression mechanism unit 18, and a plurality of lead wires 45 drawn out from the stator 43 and electrically connected to the sealed terminals of the terminal block 32. The motor unit 17 may be an open-wound motor, a star-connected motor, or a motor with multiple systems, for example, two systems of three-phase windings.

[0031] The rotor 44 comprises a rotor core (not shown) having magnet housing holes, and permanent magnets (not shown) housed in the magnet housing holes. The rotor 44 is fixed to the crankshaft 19. The rotational centerlines C of the rotor 44 and the crankshaft 19 substantially coincide with the centerline of the stator 43. Furthermore, the rotational centerlines C of the rotor 44 and the crankshaft 19 substantially coincide with the centerline of the sealed container 16.

[0032] The multiple lead wires 45 are power lines that supply power to the stator 43, and are so-called lead wires. Multiple lead wires 45 are wired depending on the type of motor unit 17, that is, whether it is an open winding type or a star connection.

[0033] The crankshaft 19 connects the motor unit 17 and the compression mechanism unit 18. The crankshaft 19 is rotatably integrated with the rotor 44 and extends downward from the rotor 44. The crankshaft 19 has a main shaft portion 47 located in the middle, a plurality of eccentric portions 48 located below the main shaft portion 47, and a sub-shaft portion 49 located below the plurality of eccentric portions 48. The main shaft portion 47 is rotatably supported by a main bearing 21, and the sub-shaft portion 49 is rotatably supported by a sub-bearing 22. The main bearing 21 and the sub-bearing 22 are also part of the compression mechanism unit 18. In other words, the crankshaft 19 is arranged to pass through the compression mechanism unit 18. Each of the eccentric portions 48 is a so-called crankpin. The plurality of eccentric portions 48 include, for example, a first eccentric portion 51 and a second eccentric portion 52. The first eccentric portion 51 and the second eccentric portion 52 are disc-shaped or cylindrical in shape, with centers that do not coincide with the rotational centerline C of the crankshaft 19.

[0034] The compression mechanism 18 draws in gaseous refrigerant from the outlet pipe 12 and intermediate pipe 13 by the rotational drive of the crankshaft 19, compresses it, and discharges the refrigerant, which has been compressed to high temperature and pressure, into the sealed container 16. The compression mechanism 18 is a multi-stage rotary compression mechanism. The compression mechanism 18 comprises a first cylinder 55 located below the main bearing 21, a partition plate 56 located below the first cylinder 55, and a second cylinder 57 located between the partition plate 56 and the sub-bearing 22.

[0035] The main bearing 21, the first cylinder 55, the partition plate 56, the second cylinder 57, and the sub-bearing 22 are arranged overlapping in the vertical direction. The main bearing 21 blocks the upper surface of the first cylinder 55. The sub-bearing 22 blocks the lower surface of the second cylinder 57. The partition plate 56 blocks the lower surface of the first cylinder 55 and the upper surface of the second cylinder 57.

[0036] The first cylinder 55 is fixed to a frame 23, which is welded to the body 26 of the sealed container 16 at multiple points, by fastening members 59 such as bolts. The main bearing 21, the first cylinder 55, the partition plate 56, the second cylinder 57, and the sub-bearing 22 are fixed to each other by multiple fastening members 59 such as bolts. The main bearing 21, the first cylinder 55, the partition plate 56, the second cylinder 57, and the sub-bearing 22 are fixed inside the sealed container 16 via the frame 23.

[0037] The first cylinder 55 has a first compression chamber 61 that penetrates the first cylinder 55 vertically. The second cylinder 57 has a second compression chamber 62 that penetrates the second cylinder 57 vertically. The first compression chamber 61 and the second compression chamber 62 are disc-shaped spaces that overlap vertically via a partition plate 56. The centers of the first compression chamber 61 and the second compression chamber 62 are located on the rotational centerline C. The compression mechanism 18 compresses the low-pressure gaseous refrigerant flowing in from the accumulator 7 to medium pressure in the first compression chamber 61 and discharges it. The compression mechanism 18 also compresses the medium-pressure gaseous refrigerant discharged from the first compression chamber 61 to high pressure in the second compression chamber 62 and discharges it. The first cylinder 55 and the second cylinder 57 may be collectively referred to as "cylinders 55 and 57," and the first compression chamber 61 and the second compression chamber 62 may be collectively referred to as "compression chambers 61 and 62."

[0038] The compression mechanism 18 also includes an annular first roller 63 located in the first compression chamber 61, an annular second roller 64 located in the second compression chamber 62, a first blade 65 located radially in the first compression chamber 61 in the first cylinder 55, and a second blade 66 located radially in the second compression chamber 62 in the second cylinder 57. The first roller 63 and the second roller 64 are sometimes collectively referred to as "rollers 63 and 64," and the first blade 65 and the second blade 66 are sometimes collectively referred to as "blades 65 and 66." The rollers 63 and 64 are so-called rolling pistons, and the blades 65 and 66 are so-called vanes.

[0039] The first roller 63 is fitted onto the first eccentric portion 51 of the crankshaft 19. The second roller 64 is fitted onto the second eccentric portion 52 of the crankshaft 19. The crankshaft 19 rotates counterclockwise in a plan view of the compressor 2. When the crankshaft 19 is rotating, the two eccentric portions 48 of the crankshaft 19, namely the first eccentric portion 51 and the second eccentric portion 52, the first roller 63 and the second roller 64, as viewed from above, rotate counterclockwise around the rotation centerline C (see Figure 1) as indicated by the solid arrow R1 shown in Figure 2. The direction of rotation of the crankshaft 19 and rollers 63 and 64 is sometimes called the "rotation direction R1," and the opposite direction of rotation to rotation direction R1 is sometimes called the "counter-rotation direction R2."

[0040] The rollers 63 and 64 rotate eccentrically with respect to the central axis of the cylinders 55 and 57 and the rotational centerline C of the crankshaft 19, while contacting the inner walls of the cylinders 55 and 57 as the crankshaft 19 rotates.

[0041] The blades 65 and 66 are arranged in a straight line in the vertical direction. In other words, the two blades 65 and 66 are positioned at approximately the same location in the circumferential direction of the cylinders 55 and 57. The blades 65 and 66 are pressed against the rollers 63 and 64 by blade springs (not shown). As a result, the blades 65 and 66 reciprocate radially within the compression chambers 61 and 62 while being pushed by the rollers 63 and 64 by the rotation of the crankshaft 19. As shown in Figures 2 and 3, the blades 65 and 66 divide the space between the cylinders 55 and 57 and the rollers 63 and 64 into a suction space S1 (not shown in Figure 2) and a compression space S2. The height of the first blade 65 is the same as the height of the second blade 66. The heights of the blades 65 and 66 are approximately the same as the heights of the compression chambers 61 and 62.

[0042] The first cylinder 55 has a first suction section 68 and a first discharge section 69 connected to the first compression chamber 61. The first suction section 68 extends outward from the inner wall surface of the first compression chamber 61, and its outer end is connected to the inner end of the suction end 35 of the sealed container 16. The first discharge section 69 is recessed outward from the inner wall surface of the first compression chamber 61, for example, and opens to the lower surface of the first cylinder 55. The first suction section 68 is positioned adjacent to the first blade 65 on the rotational direction R1 side, and the first discharge section 69 is positioned adjacent to the first blade 65 on the counter-rotational direction R2 side.

[0043] The second cylinder 57 has a second suction section 71 and a second discharge section 72 connected to the second compression chamber 62. The second suction section 71 extends outward from the inner wall surface of the second compression chamber 62, and its outer end is connected to the inner end of the intermediate suction end 37 of the sealed container 16. The second discharge section 72 is recessed outward from the inner wall surface of the second compression chamber 62, for example, and opens to the lower surface of the second cylinder 57. The second suction section 71 is arranged alongside the second blade 66 on the rotational direction R1 side, and the second discharge section 72 is arranged adjacent to the second blade 66 on the counter-rotational direction R2 side. The first suction section 68 and the second suction section 71 may be collectively referred to as "suction sections 68, 71," and the first discharge section 69 and the second discharge section 72 may be collectively referred to as "discharge sections 69, 72."

[0044] The partition plate 56 and the second cylinder 57 have intermediate-pressure passages 75 connected to the first discharge section 69 of the first compression chamber 61. The intermediate-pressure passages 75 are passages for the refrigerant that has been compressed to an intermediate pressure in the first compression chamber 61. The intermediate-pressure passage 75 of the partition plate 56 includes passages provided within the partition plate 56 and extending along the upper and lower surfaces of the partition plate 56. The intermediate-pressure passage 75 of the second cylinder 57 includes a crank-shaped passage provided outside the second compression chamber 62 and bending outwards from the top. The intermediate-pressure passage 75 of the partition plate 56 is connected to the first discharge section 69 of the first compression chamber 61, and the intermediate-pressure passage 75 of the second cylinder 57 is connected to the inner end of the intermediate discharge end 36 of the sealed container 16.

[0045] The partition plate 56 is equipped with a first discharge valve 76 that discharges the refrigerant compressed in the first compression chamber 61 into the intermediate pressure passage 75. The first discharge valve 76 opens its discharge port (not shown) when the pressure difference between the pressure in the first compression chamber 61 and the pressure in the intermediate pressure passage 75 reaches a predetermined value due to the compression operation of the compression mechanism 18, and discharges the refrigerant compressed to intermediate pressure into the intermediate pressure passage 75 of the partition plate 56. The refrigerant discharged into the intermediate pressure passage 75 of the partition plate 56 is guided out of the sealed container 16 from the intermediate discharge end 36 via the intermediate pressure passage 75 of the second cylinder 57. The refrigerant guided out of the sealed container 16 flows through the intermediate piping 13, is guided to the inside of the sealed container 16 from the intermediate suction end 37, and flows into the second compression chamber 62 from the second suction part 71 of the second cylinder 57.

[0046] The main bearing 21, the first cylinder 55, the partition plate 56, the second cylinder 57, and the sub-bearing 22 have a high-pressure passage 79 that penetrates vertically and is interconnected with each other. The high-pressure passage 79 is a passage for high-pressure gaseous refrigerant that extends linearly vertically across the main bearing 21, the first cylinder 55, the partition plate 56, the second cylinder 57, and the sub-bearing 22.

[0047] The compression mechanism 18 includes a second discharge valve 81 provided on the sub-bearing 22 for discharging the refrigerant compressed in the second compression chamber 62, and a first discharge muffler 82 that covers the second discharge valve 81 and the high-pressure passage 79. The second discharge valve 81 opens its discharge port (not shown) when the pressure difference between the pressure in the second compression chamber 62 and the pressure in the first discharge muffler 82 reaches a predetermined value due to the compression action of the compression mechanism 18, and discharges the refrigerant compressed to high pressure into the first discharge muffler 82. The refrigerant discharged from the second discharge valve 81 into the first discharge muffler 82 is guided upward to the compression mechanism 18 through the high-pressure passage 79. The first discharge valve 76 and the second discharge valve 81 are sometimes collectively referred to as "discharge valves 76 and 81".

[0048] Furthermore, the compression mechanism 18 includes a second discharge muffler 83 provided on the main bearing 21 and covering the high-pressure passage 79. The second discharge muffler 83 partitions the space from which high-pressure refrigerant is discharged from the high-pressure passage 79. The second discharge muffler 83 has a discharge port (not shown) connecting the inside and outside of the second discharge muffler 83. The high-pressure refrigerant discharged into the second discharge muffler 83 is discharged into the sealed container 16 through the discharge port.

[0049] Figure 4 is a longitudinal cross-sectional view of a partition plate of a compressor according to an embodiment of the present invention.

[0050] As shown in Figures 1 and 4, the partition plate 56 is a laminate of multiple plates that overlap vertically. The partition plate 56 comprises a first partition plate half 91 and a second partition plate half 92 that overlap vertically. The substantial shape of the first partition plate half 91 and the second partition plate half 92 is a disc shape with substantially the same thickness. The first partition plate half 91, which is positioned on the upper side, has a recess 91a (recess, groove) that opens to the lower surface of the first partition plate half 91. The second partition plate half 92, which is positioned on the lower side, has a recess 92a (recess, groove) that opens to the upper surface of the second partition plate half 92. The medium-pressure flow path 75 of the partition plate 56 is a space partitioned by the recess 91a (recess, recess) of the first partition plate half 91 and the recess 92a (recess, recess) of the second partition plate half 92. The first partition plate half 91 has a hole 91b that connects the recess 91a to the first compression chamber 61. The first discharge valve 76 is provided in the recess 91a of the first partition plate half 91 and opens and closes the hole 91b. The second partition plate half 92 has a hole 92b that connects the recess 92a to the intermediate pressure passage 75 of the second cylinder 57.

[0051] The vertical thickness of the first partition plate half 91 and the vertical thickness of the second partition plate half 92 are substantially the same, while the depth of the recess 92a in the second partition plate half 92 is shallower than the depth of the recess 91a in the first partition plate half 91. In other words, the thickness t2 of the bottom plate portion of the recess 92a in the second partition plate half 92 is greater than the thickness t1 of the bottom plate portion of the recess 91a in the first partition plate half 91. The bottom plate portion of the recess 91a in the first partition plate half 91 blocks the first compression chamber 61, and the bottom plate portion of the recess 92a in the second partition plate half 92 blocks the second compression chamber 62.

[0052] Incidentally, the multi-stage compression mechanism 18 compresses low-pressure refrigerant to medium-pressure refrigerant in the first compression chamber 61, and then compresses the medium-pressure refrigerant to high-pressure refrigerant in the second compression chamber 62. In other words, the second partition plate half 92 bears a higher pressure load than the first partition plate half 91. Therefore, by making the thickness t2 of the bottom plate portion of the recess 92a of the second partition plate half 92 thicker than the thickness t1 of the bottom plate portion of the recess 91a of the first partition plate half 91, the rigidity of the first partition plate half 91 overlapping the first cylinder 55 and the rigidity of the second partition plate half 92 overlapping the second cylinder 57 are optimized. In other words, the rigidity of the partition plate 56, which is a laminate of the first partition plate half 91 and the second partition plate half 92, is optimized. The partition plate 56, with its optimized rigidity, effectively prevents refrigerant leakage at both the mating surface between the first compression chamber 61 and the partition plate 56, and at the mating surface between the second compression chamber 62 and the partition plate 56.

[0053] Here, the suction pressure Ps of the first compression chamber 61, the intermediate pressure Pm discharged from the first compression chamber 61 and supplied to the second compression chamber 62 via the intermediate pressure flow path 75, and the discharge pressure Pd of the second compression chamber 62 are in the relationship (suction pressure Ps) < (intermediate pressure Pm) < (discharge pressure Pd). During operation, the condition (Pd - Pm) > (Pm - Ps) always holds. Under these conditions, each pressure differs depending on the operating conditions. The intermediate pressure Pm changes according to the relationship Pm = √(Pd × Ps).

[0054] Therefore, a differential pressure (Pm-Ps) surface pressure load acts on the recess 91a of the first partition plate half 91, and a differential pressure (Pd-Pm) surface pressure load acts on the recess 92a of the second partition plate half 92.

[0055] The first partition plate half 91 and the second partition plate half 92 have substantially the same thickness, while the thickness t2 of the bottom plate portion of the second partition plate half 92 is greater than the thickness t1 of the bottom plate portion of the first partition plate half 91. These dimensional relationships optimize the rigidity required for the partition plate 56.

[0056] By making the thickness dimensions of the first partition plate half 91 and the second partition plate half 92 the same, the materials of the first partition plate half 91 and the second partition plate half 92 can be made common. Also, by providing recesses in both the first partition plate half 91 and the second partition plate half 92 that face each other vertically, the passage area of the medium-pressure flow path 75 is maintained, and the performance can be improved without degradation, and the rigidity of the entire partition plate 56 can be enhanced. When the rigidity of the entire partition plate 56 is enhanced, deformation of the partition plate 56 is suppressed, and refrigerant leakage from the medium-pressure flow path 75 is prevented.

[0057] Also, the thickness t3 in the vicinity of the valve seat where the hole 91b and the first discharge valve 76 are arranged may be equal to or even smaller than t1. Thereby, while ensuring the rigidity required for the pressure difference, the volume of the hole 91b portion can be reduced.

[0058] The refrigerant in the volume portion of the hole 91b is not discharged from the first cylinder 55. Therefore, the hole 91b becomes a dead volume, causing a decrease in volumetric efficiency and a reduction in the efficiency of the compressor. Thus, by setting it within the range of t3 ≦ t1 < t2, the dead volume of the hole 91b is reduced, and a decrease in the efficiency of the compressor 2 is suppressed.

[0059] Also, by arranging the medium-pressure flow path 75 with the recesses 91a and 92a on the mating surface of the partition plate 56, the degree of freedom in the flow path arrangement inside and outside the compressor 2 is improved.

[0060] Furthermore, if the thickness of the first partition plate half 91 and the second partition plate half 92 are the same, the mating surface between the first partition plate half 91 and the second partition plate half 92 is located at the substantial center in the vertical direction of the partition plate 56. The mating surface between the first partition plate half 91 and the second partition plate half 92 may be positioned below the substantial center in the vertical direction of the partition plate 56, as shown by the dashed line MP1 in Figures 1 and 4. For example, the thickness of the second partition plate half 92 in the vertical direction may be made thinner to create a uniform thickness and eliminate the recess 92a, while the thickness of the first partition plate half 91 in the vertical direction may be made thicker to provide a deeper recess 91a only in the first partition plate half 91. In this case, the depth of the recess 91a should be equal to the depth of the recesses 91a and 92a in both the first partition plate half 91 and the second partition plate half 92, respectively.

[0061] Furthermore, the rigidity of the second partition plate half 92 can be further improved by positioning the joint surface between the first partition plate half 91 and the second partition plate half 92 above the effective center in the vertical direction of the partition plate 56, as shown by the dashed line MP2 in Figures 1 and 4. For example, the vertical thickness of the first partition plate half 91 can be made uniform to eliminate the recess 91a, while the vertical thickness of the second partition plate half 92 can be increased to provide a deeper recess 92a only in the second partition plate half 92. In this case, the depth of the recess 92a should be equal to the respective recesses 91a and 92a when recesses 91a and 92a are provided in both the first partition plate half 91 and the second partition plate half 92. By doing so, the rigidity of the second partition plate half 92 that closes the second compression chamber 62 can be further improved.

[0062] In other words, the partition plate 56 only needs to have a recess in at least one of the first partition plate half 91 and the second partition plate half 92 that demarcates the medium-pressure flow path 75, that is, at least one of the recesses 91a and 92a.

[0063] Figure 5 is a longitudinal cross-sectional view of another example of a partition plate for a compressor according to an embodiment of the present invention.

[0064] As shown in Figure 5, the partition plate 56A may include a second partition plate half 92 that is thicker than the first partition plate half 91, and may also have a recess 92a in the second partition plate half 92 that is deeper than the recess 91a in the first partition plate half 91. A partition plate 56A configured in this way can have sufficient rigidity even when the pressure on the higher level side becomes higher.

[0065] Furthermore, the compression mechanism and its components, including the first cylinder 55, first eccentric section 51, first roller 63, and first blade 65 located at the top, may be referred to as the "low-pressure side" instead of the "first," and the compression mechanism and its components, including the second cylinder 57, second eccentric section 52, second roller 64, and second blade 66 located at the bottom, may be referred to as the "high-pressure side" instead of the "second." For example, the first cylinder 55 may be called the low-pressure side cylinder 55, and the second cylinder 57 may be called the high-pressure side cylinder 57. The compression mechanism located at the top may be called the low-stage compression mechanism, and the compression mechanism located at the bottom may be called the high-stage compression mechanism.

[0066] Furthermore, the intermediate piping 13 includes an upstream intermediate piping 13u that connects the first compression chamber 61 to the external muffler 39, an intermediate pipe 13m that connects the external muffler 39 to the intercooler 41, and a downstream intermediate piping 13d that connects the intercooler 41 to the second compression chamber 62. The upstream intermediate pipe 13u guides the medium-pressure refrigerant gas discharged from the first compression chamber 61 to the outside of the sealed container 16.

[0067] The downstream intermediate pipe 13d merges with the second refrigerant pipe 9 outside the sealed container 16. The piping downstream from the junction of the downstream intermediate pipe 13d and the second refrigerant pipe 9 serves both the second refrigerant pipe 9 and the downstream intermediate pipe 13d. The downstream intermediate pipe 13d guides the medium-pressure refrigerant gas, discharged from the external muffler 39 and passing through the intercooler 41, to the second compression chamber 62 inside the sealed container 16.

[0068] The compressor 2 may also be equipped with a second external muffler 101 on the suction side of the second compression chamber 62, in addition to the external muffler 39 on the discharge side of the first compression chamber 61. The external muffler 39 reduces pressure pulsation of the medium-pressure refrigerant gas discharged from the first compression chamber 61. Reducing pressure pulsation reduces vibration of the intermediate piping 13 excited by the refrigerant gas flowing downstream from the external muffler 39. The second external muffler 101 is connected to piping that serves as both the second refrigerant piping 9 and the downstream intermediate piping 13d. The second external muffler 101 reduces pressure pulsation of the medium-pressure refrigerant gas drawn into the second compression chamber 62. Reducing pressure pulsation reduces vibration of the intermediate piping 13, vibration of the compressor 2, and ambient noise, ensuring reliability.

[0069] The cylinders 55 and 57, the rollers 63 and 64, and the eccentric portion 48 of the crankshaft 19 will be described further below.

[0070] The height of the first cylinder 55 is approximately the same as the height of the first compression chamber 61. The height of the second cylinder 57 is approximately the same as the height of the second compression chamber 62. The heights of the first compression chamber 61 and the second compression chamber 62 are the same. The inner diameter D1 of the first compression chamber 61 is greater than the inner diameter D2 of the second compression chamber 62. The volume of the first compression chamber 61 is greater than the volume of the second compression chamber 62.

[0071] The inner wall surfaces of the first compression chamber 61 with an inner diameter of D1 and the inner wall surface of the second compression chamber 62 with an inner diameter of D2 are located inward from the inner wall surface of the intermediate pressure passage 75 provided in the partition plate 56 in a plan view. The inner wall surface of the intermediate pressure passage 75 provided in the partition plate 56 includes, for example, a surface parallel to the rotation centerline C.

[0072] As shown in Figure 2, the first eccentric portion 51 of the crankshaft 19 is eccentric by a first eccentric length L1 from the rotation centerline C. In other words, the first eccentric length L1 of the first eccentric portion 51 is the length from the rotation centerline C to the center of the first eccentric portion 51. As shown in Figure 3, the second eccentric portion 52 of the crankshaft 19 is eccentric by a second eccentric length L2 from the rotation centerline C. In other words, the second eccentric length L2 of the second eccentric portion 52 is the length from the rotation centerline C to the center of the second eccentric portion 52. It is preferable that the second eccentric length L2 is smaller than the first eccentric length L1. Note that the first eccentric portion 51 and the second eccentric portion 52 are eccentric with a phase difference of 180 degrees, and Figures 2 and 3 show the state of the eccentric portions at the same timing.

[0073] The center of the first roller 63 coincides with the center of the first eccentric portion 51. The first roller 63 rotates eccentrically with a first eccentricity length L1 from the rotation centerline C. The center of the second roller 64 coincides with the center of the second eccentric portion 52. The second roller 64 rotates eccentrically with a second eccentricity length L2 from the rotation centerline C.

[0074] The suction space S1 of the compression chambers 61 and 62, partitioned by the blades 65 and 66 and the rollers 63 and 64, is the space from the side of the blades 65 and 66 on the rotational direction R1 side to the contact point between the rollers 63 and 64 and the inner wall surface of the compression chambers 61 and 62. The compression space S2 is the space from the side of the blades 65 and 66 on the counter-rotational direction R2 side to the contact point between the rollers 63 and 64 and the inner wall surface of the compression chambers 61 and 62. In other words, within the space partitioned by the blades 65 and 66 and the rollers 63 and 64 in the cylinders 55 and 57, the space connected to the suction sections 68 and 71 is the suction space S1, and the space connected to the discharge sections 69 and 72 is the compression space S2. For example, when the rollers 63 and 64 are positioned in the direction of the blades 65 and 66, the space connected to the suction sections 68 and 71 and the discharge sections 69 and 72 is not distinguished as either the suction space S1 or the discharge space S2.

[0075] Figure 6(a) is a cross-sectional view along the line B-B' shown in Figure 3, and (b) is a partial cross-sectional view along the line D-D' shown in (a). In Figure 6(a), the second eccentric portion 52, the second roller 64, and the second blade 66 are omitted.

[0076] As shown in Figures 3 and 6, the second cylinder 57 has a groove 104 between the second blade 66 and the second suction section 71. The groove 104 is located adjacent to the second blade 66 on the rotational direction R1 side. The groove 104 extends along the inner wall surface of the second compression chamber 62 from the rotational direction R1 side of the second blade 66 to the counter-rotational direction R2 side of the second suction section 71. The rotational direction end edge of the groove 104 is connected to the second suction section 71. The groove 104 is provided by recessing the upper part of the inner wall surface of the second compression chamber 62 outward.

[0077] The following describes the refrigerant suction and compression operations in the compression chambers 61 and 62.

[0078] The rollers 63 and 64 of the compression mechanism 18 rotate within the compression chambers 61 and 62 of the cylinders 55 and 57 by the rotational power of the electric motor 17. The suction space S1 of the compression chambers 61 and 62 expands when the rollers 63 and 64, which are located in the direction of the blades 65 and 66, begin to rotate in the rotational direction R1, and refrigerant flows in from the suction sections 68 and 71. The compression space S2 contracts when the rollers 63 and 64, which are located in the direction of the blades 65 and 66, begin to rotate in the rotational direction R1, compressing the refrigerant in the compression space S2 and discharging it from the discharge sections 69 and 72.

[0079] The suction start angle α at which refrigerant suction begins in the suction space S1 is the displacement angle from the time the rollers 63 and 64, which are oriented in the direction of the blades 65 and 66, rotate in the rotational direction R1 until the inflow of refrigerant from the suction sections 68 and 71 begins. The suction start angle α1 of the first compression chamber 61 is the angle between the centerline of the first blade 65 and the centerline of the first suction section 68, when the first compression chamber 61 is viewed from above. The suction start angle α2 of the second compression chamber 62 is the angle between the centerline of the second blade 66 and the line connecting the tip of the groove 104 on the second blade 66 side and the rotational centerline C, when the second compression chamber 62 is viewed from above. The suction start angle α1 of the first compression chamber 61 and the suction start angle α2 of the second compression chamber 62 are approximately the same.

[0080] While the rollers 63 and 64 rotate from the direction of the suction sections 68 and 71 to the direction of the discharge sections 69 and 72 in the rotational direction R1, refrigerant flows into the suction space S1 which is in communication with the suction sections 68 and 71.

[0081] In other words, in the first cylinder 55, there is no distinction between the suction space S1 and the discharge space S2 while the roller 63 rotates from the orientation of the blade 65 to the suction start angle α1=β1. While the roller 63 rotates in the rotational direction R1 from the position at angle α1 (=β1), which is the orientation of the suction section 68, until it reaches the discharge section 69, refrigerant flows into the suction space S1 which is in communication with the suction section 68.

[0082] Furthermore, in the second cylinder 57, there is no distinction between the suction space S1 and the discharge space S2 while the roller 64 rotates from the orientation of the blade 66 to the compression start angle β2. While the roller 63 rotates from the position at angle β2, which is the orientation of the suction section 68, in the rotational direction R1 until it reaches the discharge section 69, refrigerant flows into the suction space S1 which is in communication with the suction section 71.

[0083] The compression start angle β at which refrigerant compression begins in the compression space S2 is the central angle between the positions of rollers 63 and 64 in the orientation of blades 65 and 66 and the positions of rollers 63 and 64 that have rotated in the rotational direction R1 and at which refrigerant compression begins. The compression start angle β1 of the first compression chamber 61 is the angle between the centerline of the first blade 65 and the centerline of the first suction section 68 when the first compression chamber 61 is viewed from above. The compression start angle β2 of the second compression chamber 62 is the angle between the centerline of the second blade 66 and the centerline of the second suction section 71 when the second compression chamber 62 is viewed from above. The compression start angle β2 of the second compression chamber 62 is greater than the compression start angle β1 of the first compression chamber 61.

[0084] While rollers 63 and 64 rotate from the orientation of blades 65 and 66 to the compression start angle β, that is, while rollers 63 and 64 rotate β degrees from the orientation of blades 65 and 66, the compression space S2 is connected to the suction sections 68 and 71 (the second suction section 71 and groove 104 in the compression space S2 of the second compression chamber 62). As a result, refrigerant flows out into the suction sections 68 and 71 (the second suction section 71 and groove 104 in the compression space S2 of the second compression chamber 62), and the refrigerant is not compressed to a large extent. While rollers 63 and 64 rotate from the orientation of suction sections 68 and 71 to the orientation of blades 65 and 66, that is, while rollers 63 and 64 rotate (360-β) degrees from suction sections 68 and 71, the compression space S2 is not connected to the suction sections 68 and 71 (the second suction section 71 and groove 104 in the compression space S2 of the second compression chamber 62). Therefore, the refrigerant is compressed. When the pressure in the compressed space S2 rises to a predetermined pressure, the discharge holes of the discharge valves 76 and 81 open and the refrigerant at the predetermined pressure is discharged from the discharge sections 69 and 72.

[0085] When rollers 63 and 64 rotate by (360-β) degrees in this manner and are positioned in the direction of blades 65 and 66, the volume of the compression space S2 becomes zero, and the discharge of all refrigerant within the compression space S2 is completed. The volume of refrigerant discharged from the discharge sections 69 and 72 of the compression space S2 when rollers 63 and 64, positioned in the direction of blades 65 and 66, complete one rotation is determined by the volumes of the compression chambers 61 and 62, the outer diameters d1 and d2 of the rollers 63 and 64, the heights of the cylinders 55 and 57, and the compression start angle β. For this reason, the discharge volume of the first compression chamber 61 is set to be larger than the discharge volume of the second compression chamber 62, effectively improving the compression efficiency of the compressor 2.

[0086] As shown in Figures 6(a) and 6(b), the groove 104 is provided by recessing only the upper part of the inner wall surface of the second compression chamber 62 outwards, but is not limited to this as long as it is connected to the second suction section 71.

[0087] Figure 7(a) is a cross-sectional view showing a modified example of the groove in an embodiment of the present invention, and (b) is a partial cross-sectional view of the line E-E' shown in (a).

[0088] Figure 8(a) is a cross-sectional view showing a modified example of the groove in an embodiment of the present invention, and (b) is a partial cross-sectional view of the line F-F' shown in (a).

[0089] Figure 9(a) is a cross-sectional view showing a modified example of the groove in an embodiment of the present invention, and (b) is a partial cross-sectional view of the line G-G' shown in (a). Figures 7(a), 8(a), and 9(a) are cross-sectional views of the same location as in Figure 6(a), but the second eccentric portion 52, the second roller 64, and the second blade 66 are omitted.

[0090] As shown in Figures 7(a) and 7(b), a modified form of groove 104, groove 104e, may be provided by recessing at least one of the upper and lower parts of the inner wall surface of the second compression chamber 62 outward. As shown in Figures 8(a) and 8(b), a modified form of groove 104, groove 104f, may be provided by recessing only the intermediate portion between the upper and lower parts of the inner wall surface of the second compression chamber 62 outward. Furthermore, the cross-sectional shape of these grooves 104, 104e, and 104f is a stepped shape created by recessing the inner wall surface of the second compression chamber 62 outward, but is not limited to this. For example, as shown in Figure 9(b), the cross-sectional shape of groove 104g, a modified form of groove 104, may be tapered.

[0091] Furthermore, the groove 104 extends along the inner wall surface of the second compression chamber 62 from the rotation direction R1 side of the second blade 66 to the second suction section 71, but is not limited to this. The groove 104 only needs to be connected to the second suction section 71 and allow the compression start angle β2 to be set to be greater than the compression start angle β1 of the first compression chamber 61. For example, the groove 104 may extend along at least one of the rotation direction R1 side and the anti-rotation direction R2 side of the second suction section 71. In this case, it is preferable to make the suction start angle α2 approximately the same as the suction start angle α1 of the first compression chamber 61. To do this, for example, the second suction section 71 may be positioned adjacent to the rotation direction side of the second blade 66, and the groove 104 may be positioned adjacent to the rotation direction side of the second suction section 71 and extend along the rotation direction R1.

[0092] As described above, the refrigeration cycle device 1 and compressor 2 according to this embodiment include a compression mechanism 18 having a low-pressure side cylinder 55 including a low-pressure side compression chamber 61 and a high-pressure side cylinder 57 including a high-pressure side compression chamber 62. The height of the low-pressure side compression chamber 61 is the same as the height of the high-pressure side compression chamber 62, and the inner diameter dimension D1 of the low-pressure side compression chamber 61 is larger than the inner diameter dimension D2 of the high-pressure side compression chamber 62. Therefore, the volume of the high-pressure side compression chamber 62 is smaller than the volume of the low-pressure side compression chamber 61, and the exhaust volume of the high-pressure side compression chamber 62 is smaller than the exhaust volume of the low-pressure side compression chamber 61. As a result, the compression efficiency of the multi-stage compression compressor 2 is improved. Furthermore, the heights of cylinders 55 and 57 are the same, and the volume difference between cylinders 55 and 57 is not determined by the difference in height, but by the difference in the inner diameter dimensions of the compression chambers 61 and 62. Therefore, the height dimensions of blades 65 and 66 are substantially unified. The operation of blades 65 and 66, whose heights are standardized, is easier to stabilize. Furthermore, the compression mechanism 18 is miniaturized, mainly in the height direction.

[0093] Furthermore, the refrigeration cycle device 1 and compressor 2 according to this embodiment include a crankshaft 19 having a low-pressure side eccentric portion 51 that is eccentric by a first eccentric length L1 from the central axis of the sealed container 16, and a high-pressure side eccentric portion 52 that is eccentric by a second eccentric length L2 from the central axis of the sealed container 16. The first eccentric length L1 of the low-pressure side eccentric portion 51 is greater than the second eccentric length L2 of the high-pressure side eccentric portion 52. As a result, the outer diameter of the low-pressure side roller 63 that fits into the low-pressure side eccentric portion 51 becomes smaller, and the elimination volume of the low-pressure side compression chamber 61 becomes larger. Also, the outer diameter of the high-pressure side roller 64 that fits into the high-pressure side eccentric portion 52 becomes larger, and the elimination volume of the high-pressure side compression chamber 62 becomes smaller. Therefore, the compression efficiency of the compressor 2 is further improved, and the expansion of the compression mechanism 18 is suppressed.

[0094] Furthermore, in the refrigeration cycle device 1 and compressor 2 according to this embodiment, the compression start angle β1 of the high-pressure side compression chamber 62 is set to be greater than the compression start angle β2 of the low-pressure side compression chamber 61. As a result, the exhaust volume of the high-pressure side compression chamber 62 is reduced. Consequently, the compression efficiency of the compressor 2 is further improved, and the expansion of the compression mechanism 18 is suppressed.

[0095] Furthermore, the refrigeration cycle device 1 and compressor 2 according to this embodiment include a high-pressure side cylinder 57 provided on the wall surface partitioning the high-pressure side compression chamber 62 and having a groove 104 connected to the high-pressure side suction section 71 of the high-pressure side compression chamber 62. As a result, the suction start angle α2 of the suction space S1 of the high-pressure side compression chamber 62 can be set to be small, and the compression start angle β2 of the compression space S2 can be set to be large. Consequently, the compression efficiency of the compressor 2 is further improved, and the expansion of the compression mechanism 18 is suppressed.

[0096] Furthermore, the refrigeration cycle device 1 and compressor 2 according to this embodiment include a compression mechanism 18 having a partition plate 56 provided between the low-pressure side cylinder 55 and the high-pressure side cylinder 57 of the compression mechanism 18. The partition plate 56 and the high-pressure side cylinder 57 have an intermediate-pressure passage 75. The intermediate-pressure passage 75 connects the low-pressure side discharge section 69 of the low-pressure side compression chamber 61 and the high-pressure side suction section 71 of the high-pressure side compression chamber 62. Therefore, expansion of the compression mechanism 18 is suppressed by efficiently providing the intermediate-pressure passage 75.

[0097] Furthermore, the partition plate 56 of the refrigeration cycle device 1 and compressor 2 according to this embodiment has a first partition plate half 91 and a second partition plate half 92 superimposed below the first partition plate half 91. The partition plate 56 has a portion of the intermediate pressure flow path 75, i.e., recesses 91a and 92a, at the joint surface of the first partition plate half 91 and the second partition plate half 92. As a result, a portion of the intermediate pressure flow path 75 is efficiently formed in the partition plate 56, improving the degree of freedom in flow path arrangement. In addition, the thickness of the second partition plate half 92 below the portion of the intermediate pressure flow path 75 is greater than the thickness of the first partition plate half 91 above the portion of the intermediate pressure flow path 75. This optimizes the rigidity of the partition plate 56 and suppresses refrigerant leakage.

[0098] Furthermore, in the refrigeration cycle device 1 and compressor 2 according to this embodiment, the intermediate pressure passage 75 of the partition plate 56 is connected to the discharge section 69 of the low-pressure side compression chamber 61, and the intermediate pressure passage 75 of the high-pressure side cylinder is connected to the intermediate pressure passage 75 of the partition plate 56 and is located outside the high-pressure side compression chamber 62. Therefore, the expansion of the compression mechanism 18 is suppressed by efficiently providing the intermediate pressure passage 75.

[0099] Furthermore, the refrigeration cycle device 1 and compressor 2 according to this embodiment include an intermediate pipe 13 provided on the outside of the sealed container 16. The intermediate pressure passage 75 is connected to the high-pressure side suction section 71 of the high-pressure side compression chamber 62 via the intermediate pipe 13. Therefore, the intermediate pressure passage 75 can be connected to the high-pressure side suction section 71 of the high-pressure side compression chamber 62 via the intermediate pipe 13.

[0100] Therefore, according to the refrigeration cycle device 1 and compressor 2 of this embodiment, a decrease in the reliability of the multi-stage compression mechanism 18 can be prevented and miniaturized.

[0101] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of symbols]

[0102] 1...Refrigeration cycle unit, 2...Compressor, 3...Radiator, 4...First expansion unit, 5...Second expansion unit, 6...Heat absorber, 7...Accumulator, 8...First refrigerant piping, 9...Second refrigerant piping, 12...Outlet pipe, 13...Intermediate piping, 13u...Upstream intermediate piping, 13m...Intermediate pipe, 13d...Downstream intermediate piping, 16...Sealed container, 17...Electric motor unit, 18...Compression mechanism unit, 19...Crankshaft, 21...Main bearing, 21 ...Main bearing, 22...Sub-bearing, 22...Sub-shaft section, 23...Frame, 26...Body section, 27...Upper end plate, 28...Lower end plate, 31...Discharge pipe, 32...Terminal block, 35...Suction end, 36...Intermediate discharge end, 37...Intermediate suction end, 38...Fixing device, 39...External muffler, 41...Intercooler, 43...Stator, 44...Rotor, 45...Outlet wire, 47...Main shaft section, 48...Eccentric section, 49...Sub-shaft section, 51...First eccentric 52...Central part, 55...Second eccentric part, 56...First cylinder, 57...Partition plate, 59...Second cylinder, 61...First compression chamber, 62...Second compression chamber, 63...First roller, 64...Second roller, 65...First blade, 66...Second blade, 68...First suction part, 69...First discharge part, 71...Second suction part, 72...Second discharge part, 75...Medium pressure flow path, 76...First discharge valve, 79...High pressure flow path Path, 81...Second discharge valve, 82...First discharge muffler, 83...Second discharge muffler, 91...First partition plate half, 91a...Recess, 91b...Hole, 92...Second partition plate half, 92a...Recess, 92b...Hole, 101...Second external muffler, 104, 104e, 104f, 104g...Grooves, d1, d2...Outer diameter dimensions, D1, D2...Inner diameter dimensions, S1...Suction space, S2...Compression space, t1, t2...Thickness.

Claims

1. A sealed container having a center line extending in the vertical direction, The electric motor unit is provided inside the sealed container, A crankshaft having a low-pressure side eccentric portion and a high-pressure side eccentric portion provided below the low-pressure side eccentric portion, and being rotationally driven by the electric motor around the center line, A compression mechanism comprising: a low-pressure side cylinder having a low-pressure side compression chamber for compressing and discharging the introduced gaseous refrigerant using the power of the low-pressure side eccentric part; a high-pressure side cylinder having a high-pressure side compression chamber for compressing the refrigerant discharged from the low-pressure side compression chamber using the power of the high-pressure side eccentric part; and a partition plate provided between the low-pressure side cylinder and the high-pressure side cylinder, The low-pressure side eccentric portion is positioned eccentrically from the center line of the sealed container, such that the center of the low-pressure side eccentric portion is displaced by a first eccentric length from the center line of the sealed container. The high-pressure side eccentric portion is positioned eccentrically from the center line of the sealed container, such that the center of the high-pressure side eccentric portion is displaced by a second eccentric length different from the first eccentric length from the center line of the sealed container. The height of the low-pressure compression chamber is the same as the height of the high-pressure compression chamber. The inner diameter of the low-pressure compression chamber is larger than the inner diameter of the high-pressure compression chamber. The partition plate and the high-pressure side cylinder have a medium-pressure passage, The aforementioned intermediate-pressure flow path connects the discharge section of the low-pressure compression chamber and the suction section of the high-pressure compression chamber. The partition plate comprises a first partition plate half and a second partition plate half superimposed below the first partition plate half, and a portion of the intermediate pressure flow path is provided at the joint surface of the first partition plate half and the second partition plate half. The first partition plate half has a recess that is open on the lower surface of the first partition plate half and a hole that connects the recess to the low-pressure side compression chamber. The second partition plate half has a recess that is open on the upper surface of the second partition plate half, The partition plate is equipped with a first discharge valve that discharges the refrigerant compressed in the low-pressure compression chamber into the medium-pressure flow path. The first discharge valve is provided in the recess of the first partition plate half and opens and closes the hole. When the thickness of the bottom plate portion of the recess in the first partition plate half is t1, the thickness of the bottom plate portion of the recess in the second partition plate half is t2, and the thickness of the first partition plate half near the valve seat where the hole and the first discharge valve are arranged is t3, A rotary compressor that satisfies the following relation (1). t3≦t1<t2 (1)

2. The rotary compressor according to claim 1, wherein the first eccentricity length is greater than the second eccentricity length.

3. The rotary compressor according to claim 1 or 2, wherein the compression start angle of the high-pressure side compression chamber is greater than the compression start angle of the low-pressure side compression chamber.

4. The rotary compressor according to any one of claims 1 to 3, wherein the high-pressure side cylinder is provided on the wall surface partitioning the high-pressure side compression chamber and has a groove connected to the suction portion of the high-pressure side compression chamber.

5. A rotary compressor according to any one of claims 1 to 4, satisfying the following relational expression (1'). t3<t1<t2 (1')

6. The second partition plate half is thicker than the first partition plate half, The rotary compressor according to any one of claims 1 to 5, wherein the recess of the second partition plate half is deeper than the recess of the first partition plate half.

7. The sealed container is provided with an intermediate pipe located on the outside, The rotary compressor according to any one of claims 1 to 6, wherein the intermediate pressure flow path is connected to the suction section of the high-pressure compression chamber via the intermediate piping.

8. A rotary compressor according to any one of claims 1 to 7, Heat sink and, Expansion device and Heat absorber and A refrigeration cycle apparatus comprising a rotary compressor, a heat exchanger, an expansion device, and a refrigerant piping for circulating the refrigerant, connecting the rotary compressor, the heat exchanger, the expansion device, and the heat absorber.

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