JP4948557B2 - Multistage compressor and refrigeration air conditioner - Google Patents

Description

  The present invention relates to, for example, a multistage compressor used in a vapor compression refrigeration cycle and a refrigeration air conditioner.

A vapor compression refrigeration cycle using a rotary compressor is used in a refrigeration air conditioner such as a refrigerator, an air conditioner, or a heat pump type hot water heater.
From the viewpoint of preventing global warming, it is necessary to save energy and improve efficiency of the vapor compression refrigeration cycle. An example of a vapor compression refrigeration cycle that achieves energy saving and efficiency is an injection cycle that uses a two-stage rotary compressor. In order to make the injection cycle using a two-stage rotary compressor more widespread, cost reduction and further efficiency are required.

The rotary compressor is generally a hermetic compressor in which a compression unit and a motor are accommodated in a hermetic shell. A hermetic rotary compressor sucks refrigerant into a compression unit via a suction muffler. The suction muffler suppresses generation of pressure pulsation that occurs when the refrigerant is sucked, and reduces acoustic noise. The suction muffler separates the refrigerant into a gas refrigerant and a liquid refrigerant, and temporarily stores the separated liquid refrigerant. As a result, the suction muffler prevents a large amount of liquid refrigerant from entering the compression section.
In the high-pressure shell type compressor and the intermediate pressure shell type compressor, the suction muffler is juxtaposed outside the hermetic shell. And the side part of an airtight shell and the bottom part of a suction muffler are connected via a suction refrigerant pipe. Therefore, when a high-pressure shell type or intermediate pressure shell type compressor is arranged, a space for arranging the suction muffler on the side of the compressor is required. Patent Document 1 describes a compressor in which a suction muffler having a gas-liquid separation function is arranged in an axial direction above a hermetic shell and is formed in a substantially arc shape when viewed from the axial direction. Thereby, in patent document 1, the space which arrange | positions a suction muffler in the side part of the compressor became unnecessary.
On the other hand, in a low-pressure shell type compressor, it is common to separate a refrigerant from a gas refrigerant and a liquid refrigerant in a sealed shell before the refrigerant is sucked into the compression unit. For example, Patent Document 2 describes an accumulator-integrated compressor in which an accumulator for separating a liquid refrigerant and a lubricating oil is provided in a sealed shell in addition to separating the refrigerant into a gas refrigerant and a liquid refrigerant. is there.

In a two-stage rotary compressor, a pressure loss (intermediate pressure pulsation loss) is generated at an intermediate coupling portion that connects a low-stage compression portion and a high-stage compression portion in series. The pressure loss that occurs in the intermediate connection portion corresponds to the sum of the overcompression loss that occurs in the low-stage discharge portion and the insufficient expansion loss that occurs in the high-stage suction portion. In order to increase the efficiency of the two-stage rotary compressor, it is important to reduce the pressure loss that occurs at the intermediate connecting portion.
Patent Document 3 describes that the volume of the intermediate coupling portion is set larger than the displacement volume of the compression chamber of the high-stage compression portion. Thereby, in patent document 3, generation | occurrence | production of the pressure pulsation resulting from the timing shift of the refrigerant | coolant discharge in a low stage and the suction | inhalation of the refrigerant | coolant in a high stage was suppressed by the buffering action of the intermediate | middle connection part. And the pressure loss which arises in an intermediate connection part was decreased.
Patent Document 4 has a description of shifting the planar arrangement of the low-stage compression element and the high-stage compression element. Thereby, in patent document 4, the length of the intermediate | middle connection flow path was made shortest, and the followable | trackability of the suction gas in the intermediate | middle connection part was improved. And the pressure loss which arises in an intermediate connection part was decreased.

JP 2006-342743 A Japanese Patent Laid-Open No. 2007-9789 JP-A-63-138189 JP 2003-148366 A

When the suction muffler is arranged as described in Patent Document 1, the overall height of the compressor is increased. Therefore, the external volume of the compressor is the same as before.
As described in Patent Document 2, in a low-pressure shell type compressor, it is easy to provide an accumulator inside the compressor. However, in high-pressure shell type and intermediate pressure shell type compressors, it is still impossible to provide an accumulator function inside the sealed shell.
As described above, with the conventional space-saving method for the suction muffler, the effect of downsizing the compressor cannot be sufficiently obtained.

Even when the volume of the intermediate connecting portion is set large as described in Patent Document 3, when the flow path of the intermediate connecting portion is long and bent, or when there is a buffer container in the middle, the pressure The loss is great. Therefore, the followability of the refrigerant flowing through the intermediate connecting portion is deteriorated. Therefore, even if the amplitude of the intermediate pressure pulsation becomes small, a phase delay occurs, and the pressure loss increases at the intermediate connecting portion.
When the cylinder plane arrangement phase of each of the low-stage compression section and the high-stage compression section is shifted as described in Patent Document 4, the low-stage compression section and the high-stage compression, which are the features of a general two-stage rotary compressor, are described. The effect of canceling out torque fluctuations at the opposite phase in the opposite phase cannot be obtained.
As described above, there is a problem in the conventional method for reducing the pressure loss in the intermediate connecting portion.

  An object of the present invention is to achieve both reduction in size and efficiency of a multistage rotary compressor.

The multistage compressor according to the present invention is, for example,
A sealed shell;
A first compression unit provided inside the hermetic shell and compressing the refrigerant;
A second compression unit provided inside the hermetic shell and stacked on the first compression unit, and further compresses the refrigerant compressed by the first compression unit;
A suction muffler that forms a suction muffler space in which the refrigerant flows in from the outside of the sealed shell and flows out to the first compression unit;
A discharge muffler that forms a discharge muffler space in which the refrigerant is discharged from the first compression unit and flows out to the second compression unit;
The suction muffler and the discharge muffler are at least partially arranged in parallel in the stacking direction of the first compression unit and the second compression unit, and the first compression unit and the second compression unit Laminated and provided inside the sealed shell,
The discharge muffler forms, as the discharge muffler space, a predetermined space including a discharge port through which the refrigerant compressed by the first compression unit is discharged and a communication port through which the refrigerant flows out to the second compression unit,
The suction muffler is a space in a range where the discharge muffler space is formed in the stacking direction, and forms at least a part of the space other than the space where the discharge muffler space is formed as the suction muffler space. Features.

  The multistage compressor according to the present invention can achieve both reduction in size and efficiency by appropriately arranging the suction muffler, which has been conventionally externally attached to the hermetic shell, in the shell.

FIG. 2 is a cross-sectional view showing the overall configuration of the two-stage rotary compressor according to the first embodiment. FIG. 2 is an AA cross-sectional view of the two-stage rotary compressor of FIG. 1 according to the first embodiment. AA sectional drawing of the conventional two-stage rotary compressor. The figure which shows the relationship between the low stage discharge muffler specific volume of the two-stage rotary compressor which concerns on Embodiment 1 and Embodiment 2, and specific compressor efficiency. FIG. 4 is a cross-sectional view taken along line AA of the two-stage rotary compressor of FIG. FIG. 4 is a cross-sectional view taken along line AA of the two-stage rotary compressor of FIG. FIG. 4 is a cross-sectional view taken along line AA of the two-stage rotary compressor of FIG. Sectional drawing which shows the whole structure of the two-stage rotary compressor which concerns on Embodiment 3. FIG. FIG. 9 is an AA cross-sectional view of the two-stage rotary compressor of FIG. 8 according to the third embodiment. Sectional drawing which shows the whole structure of the two-stage rotary compressor which concerns on Embodiment 4. FIG. FIG. 11 is an AA cross-sectional view of the two-stage rotary compressor of FIG. 10 according to the fourth embodiment. Sectional drawing which shows the whole structure of the two-stage rotary compressor which concerns on Embodiment 5. FIG. FIG. 13 is an AA cross-sectional view of the two-stage rotary compressor of FIG. 12 according to the fifth embodiment. Schematic which shows the structure of the heating hot-water supply system which concerns on Embodiment 6. FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Here, a two-stage rotary compressor will be described as an example of a multistage compressor.
In the following description, the terms “low pressure”, “intermediate pressure”, and “high pressure” are used. However, these indicate the relative height of the refrigerant pressure, not the absolute height. “Low pressure” indicates the pressure before compression by the low-stage compression section. “Intermediate pressure” is the pressure after compression by the low-stage compression section, and indicates the pressure before compression by the high-stage compression section. “High pressure” indicates the pressure after compression by the high-stage compression section.
The two-stage compressor is roughly classified into three types according to the pressure level in the hermetic shell 8. When the internal pressure of the closed shell 8 is equal to the evaporator pressure or the suction pressure of the first compression section, it is a “low pressure shell type”. When the internal pressure of the sealed shell 8 is equal to the discharge pressure of the first compression section or the suction pressure of the second compression section, it is “intermediate pressure shell type”. When the pressure in the closed shell 8 is equal to the condenser pressure or the discharge pressure of the second compression unit, the high-pressure shell type is used. The internal pressure of the sealed shell 8 refers to the pressure of the main part of the sealed shell 8. Therefore, even in the closed shell 8, the pressure may be partially different.
In the two-stage compressor, the first compression unit is a low-stage compression unit, and the second compression unit is a high-stage compression unit. In the following embodiments, a two-stage compressor having two compression units (compression mechanisms) will be described as an example of a multistage compressor. However, the multistage compressor may be a compressor having three or more compression units (compression mechanisms).

Embodiment 1 FIG.
FIG. 1 is a cross-sectional view showing the overall configuration of the two-stage rotary compressor according to the first embodiment. 2 is a cross-sectional view taken along line AA of the two-stage rotary compressor of FIG. 1 according to the first embodiment. In FIG. 2, some constituent elements that are not originally visible in the sectional view are indicated by broken lines.
The two-stage rotary compressor according to the first embodiment includes a low-stage compression unit 10, a high-stage compression unit 20, a suction muffler 30, a low-stage discharge muffler 40, a high-stage discharge muffler 50, and a lower part inside the hermetic shell 8. A support member 60, an upper support member 70, an intermediate connecting part 80, a compressor suction pipe 1, a lubricating oil storage part 3, an intermediate partition plate 5, a drive shaft 6, and a motor part 9 are provided. The layers of the suction muffler 30 and the low-stage discharge muffler 40, the lower support member 60, the low-stage compression unit 10, the intermediate partition plate 5, the high-stage compression unit 20, the upper support member 70, and the high-stage discharge muffler 50 And the motor unit 9 are stacked in order from the lower side in the axial direction of the drive shaft 6. In addition, inside the sealed shell 8, the lubricating oil storage unit 3 is provided on the lowest side in the axial direction of the drive shaft 6.

  The low stage compression unit 10 and the high stage compression unit 20 include cylinders 11 and 21, respectively. Further, the low-stage compression unit 10 and the high-stage compression unit 20 include rotary pistons 12a and 22a and vanes 14a and 24a inside the cylinders 11 and 21, respectively. The cylinders 11 and 21 are provided with cylinder suction ports 15 and 25, discharge ports 16 and 26, discharge valves 17 and 27, and discharge valve concave installation portions 18 and 28. The low-stage compression unit 10 is stacked such that the cylinder 11 is sandwiched between the lower support member 60 and the intermediate partition plate 5. The high-stage compression unit 20 is stacked such that the cylinder 21 is sandwiched between the upper support member 70 and the intermediate partition plate 5.

The suction muffler 30 includes a suction muffler container 32, a suction muffler seal portion 33, a liquid storage portion 34, and a narrow tube 38. The suction muffler 30 is formed with a suction muffler space 31 surrounded by the suction muffler container 32 and the lower support member 60.
The suction muffler container 32 and the lower support member 60 are sealed with a suction muffler seal portion 33 so that the low-pressure refrigerant that has entered the suction muffler space 31 does not leak. The suction muffler 30 separates the refrigerant that has entered the suction muffler space 31 into gas refrigerant and liquid refrigerant. The liquid storage unit 34 is provided below the suction muffler space 31 (on the opposite side of the low-stage compression unit 10 in the longitudinal direction of the drive shaft 6) in order to temporarily store the separated liquid refrigerant. When the liquid level of the liquid refrigerant stored in the liquid storage unit 34 rises above a predetermined level, the suction muffler 30 is pumped up from the narrow tube 38 and holds the liquid storage amount within a predetermined range. The suction muffler 30 is provided with a suction muffler inlet 36 connected to the compressor suction pipe 1 and a suction muffler outlet 37 connected to the low-stage compression unit 10.

The low stage discharge muffler 40 includes a low stage discharge muffler container 42 and a low stage discharge muffler seal portion 43.
The low-stage discharge muffler 40 is formed with a low-stage discharge muffler space 41 surrounded by the suction muffler container 32 and the lower support member 60. The low-stage discharge muffler seal part 43 is sealed between the low-stage discharge muffler container 42 and the lower support member 60 so that the intermediate pressure refrigerant that has entered the low-stage discharge muffler space 41 does not leak. The low-stage discharge muffler 40 is provided with a communication port 47 that communicates with the high-stage compression unit 20 through the intermediate connection unit 80.

  For the seal portions 33 and 43, for example, an O-ring made of an elastic material or a metal packing is used.

The suction muffler 30 and the low-stage discharge muffler 40 are at least partially arranged in parallel in the axial direction (stacking direction) of the drive shaft 6. That is, the suction muffler space 31 and the low-stage discharge muffler space 41 at least partially form the same layer in the axial direction of the drive shaft 6. The suction muffler 30 and the low-stage discharge muffler 40 are stacked and arranged so as to be in contact with the discharge port side surface portion 62 of the lower support member 60. That is, the suction muffler 30 and the low-stage discharge muffler 40 are arranged so as to divide the space in contact with the discharge port side surface portion 62 of the lower support member 60.
The high stage discharge muffler 50 includes a high stage discharge muffler container 52 and a high stage discharge muffler seal portion 53. The high-stage discharge muffler 50 is formed with a high-stage discharge muffler space 51 surrounded by the high-stage discharge muffler container 52 and the upper support member 70. The high-stage discharge muffler container 52 and the upper support member 70 are sealed with a high-stage discharge muffler seal portion 53 so that the high-pressure refrigerant that has entered the high-stage discharge muffler space 51 does not leak. The high-stage discharge muffler 50 is provided with a communication port 57 that communicates with the inside of the hermetic shell 8.

  The lower support member 60 includes a lower bearing portion 61 and a discharge port side surface portion 62. The lower bearing portion 61 is formed in a cylindrical shape and supports the drive shaft 6. The discharge port side surface portion 62 is formed in a ring shape (donut shape), forms the above-described suction muffler space 31 and the low-stage discharge muffler space 41, and supports the low-stage compression unit 10. Similarly, the upper support member 70 includes an upper bearing portion 71 and a discharge port side portion 72. The upper bearing portion 71 is formed in a cylindrical shape and supports the drive shaft 6. The discharge port side surface portion 72 is formed in a ring shape (donut shape), forms the above-described high-stage discharge muffler space 51 and supports the high-stage compression section 20.

  The intermediate connection part 80 includes an intermediate connection flow path 81 and a refrigerant injection port 82. The intermediate connection channel 81 is a channel that connects the communication port 47 of the low stage discharge muffler 40 and the cylinder 21 of the high stage compression unit 20. The refrigerant injection port 82 is a port that can inject a refrigerant attached to the intermediate connection flow path 81. Further, the intermediate connection flow path 81 uses the intermediate connection pipe 84 which is a pipe welded to the outside of the sealed shell 8 as a flow path.

The flow of the refrigerant will be described. In the figure, the arrows indicate the flow of the refrigerant.
First, the low-pressure refrigerant enters the suction muffler space 31 inside the sealed shell 8 from the suction muffler inlet 36 through the compressor suction pipe 1 fixed to the sealed shell 8 ((1) in FIG. 1) (in FIG. 1). (2)). The refrigerant is separated into a gas refrigerant and a liquid refrigerant in the suction muffler space 31. After being separated into the gas refrigerant and the liquid refrigerant, the gas refrigerant is sucked from the suction muffler outlet 37 through the cylinder suction port 15 ((3) in FIG. 1) into the cylinder 11 of the low-stage compression unit 10 (FIG. 1). (4)). On the other hand, the liquid refrigerant is temporarily held inside the suction muffler space 31. The refrigerant sucked into the cylinder 11 is compressed to the intermediate pressure by the low-stage compression unit 10, and then the discharge valve 17 is opened and discharged from the discharge port 16 to the low-stage discharge muffler space 41 ((5) in FIG. 1). ). The refrigerant discharged to the low-stage discharge muffler space 41 passes through the intermediate connection flow path 81 from the communication port 47 ((6) in FIG. 1) and is sucked into the cylinder 21 of the high-stage compression unit 20 (in FIG. 1). (7)). Next, the refrigerant sucked into the cylinder 21 is compressed to a high pressure by the high-stage compression unit 20 and then discharged from the discharge port 26 to the high-stage discharge muffler space 51 ((8) in FIG. 1). Then, the refrigerant discharged to the high-stage discharge muffler space 51 is discharged to the inside of the sealed shell 8. The refrigerant discharged to the inside of the sealed shell 8 passes through the gap of the motor unit 9 above the compression unit, and then is discharged to the external refrigerant circuit through the compressor discharge pipe 2 fixed to the sealed shell 8.
Note that the refrigerant and the lubricating oil are separated while the high-pressure refrigerant passes through the inside of the sealed shell 8. The separated lubricating oil is stored in the lubricating oil storage section 3 at the bottom of the hermetic shell 8, pumped up by a rotary pump attached to the lower portion of the drive shaft 6, and supplied to the sliding section and the sealing section of each compression section.
Further, as described above, the refrigerant compressed to the high pressure in the high stage compression unit 20 and discharged into the high stage discharge muffler space 51 is discharged into the sealed shell 8. Therefore, the pressure in the sealed shell 8 is equal to the discharge pressure of the high-stage compression unit 20. Therefore, the compressor shown in FIG. 1 is a high-pressure shell type.

The compression operation of the low stage compression unit 10 and the high stage compression unit 20 will be described.
The motor unit 9 rotates the drive shaft 6 around the axis 6d to drive the compression units 10 and 20. Due to the rotation of the drive shaft 6, the rotary pistons 12 a and 22 a in the cylinders 11 and 21 are eccentrically rotated counterclockwise by the low-stage compression unit 10 and the high-stage compression unit 20, respectively. The position in the eccentric direction that minimizes the gap with the inner wall of the cylinder 11 is rotationally moved from the rotation reference phase θ _{0 in} the order of the cylinder suction port phase and the low-stage discharge port phase to compress the refrigerant. Here, the rotation reference phase is a position of a vane 14a (an example of a partition member) that partitions the inside of the cylinder into a compression chamber and a suction chamber. That is, the rotary piston 12a rotates in the counterclockwise direction from the rotation reference phase through the phase θs1 of the cylinder suction port 15 to the phase of the discharge port 16 to compress the refrigerant.
In the high-stage compression unit 20, similarly to the low-stage compression unit 10, the rotary piston 22 a rotates counterclockwise from the rotation reference phase θ ₀ to the phase of the discharge port 26 through the phase θs 2 of the cylinder suction port 25. And compresses the refrigerant. That is, in the compressor shown in this embodiment, the position of the vane 14a of the low-stage compressor 10 and the position of the vane 24a of the high-stage compressor 20 are provided in the same phase (rotation reference phase θ ₀ ). Yes.

The two-stage rotary compressor according to the first embodiment particularly has the following features (1) to (4).
1) Shape of the low-stage discharge muffler space 41 As described above, the refrigerant compressed to the intermediate pressure by the low-stage compression unit 10 is discharged from the discharge port 16 to the low-stage discharge muffler space 41. The refrigerant discharged into the low-stage discharge muffler space 41 rapidly expands in the low-stage discharge muffler space 41 and then flows into the intermediate connection channel 81 from the communication port 47.
Here, the low-stage discharge muffler container 42 is provided so that the low-stage discharge muffler space 41 is shaped to guide the flow of the refrigerant from the discharge port 16 to the communication port 47. That is, the space opposite to the communication port 47 with respect to the discharge port 16 is an ineffective flow region 49 (hatched portion indicated by reference numeral 49 in FIG. 2) in which the refrigerant flow from the discharge port 16 to the communication port 47 is unnecessarily diffused. It becomes. The ineffective flow region 49 causes the refrigerant to stagnate and increase pressure loss. Therefore, the low-stage discharge muffler container 42 is provided so that the volume of the invalid flow region 49 is reduced.
The suction muffler container 32 is provided so that the suction muffler space 31 is formed in the region where the ineffective flow region is formed in the conventional rotary compressor described below.

FIG. 3 is an AA cross-sectional view of a conventional two-stage rotary compressor. As shown in FIG. 3, the conventional low-stage discharge muffler space 141 does not form the same layer as the suction muffler space, and the sealed shell 8 except for the drive shaft 6 and the periphery of the drive shaft 6 (bearing portion). It is formed in a ring shape that covers the inside. Therefore, in the conventional low-stage discharge muffler space 141, the volume of the invalid flow region 149 (hatched portion indicated by reference numeral 149 in FIG. 3) is the effective flow region 148 (the region other than the invalid flow region 149 of the low-stage discharge muffler space 141). ) Is very large.
On the other hand, as shown in FIG. 2, in the low stage discharge muffler space 41 according to the first embodiment, the volume of the ineffective flow region 49 is small. Therefore, the pressure loss in the low-stage discharge muffler 40 can be reduced. Further, the compressor can be reduced in size by arranging the suction muffler 30 in the space created by reducing the volume of the ineffective flow region 49.

For example, the low-stage discharge muffler space 41 has an arc of a circle (circle 44 shown by a broken line in FIG. 3) having a diameter that is a straight line connecting the discharge port 16 and the communication port 47 in the AA cross section. A region formed by the inner wall (shaded portion 45 in FIG. 3) is a space having a cross section. Further, the low-stage discharge muffler space 41 has a cross-sectional area formed by an elliptical elliptic arc whose long side is a straight line connecting the discharge port 16 and the communication port 47 and the inner wall of the sealed shell 8 in the AA cross section. It may be a space.
The straight line connecting the discharge port 16 and the communication port 47 is a straight line connecting two farthest points of the discharge port 16 and the communication port 47 in the AA cross section. That is, the circle or ellipse includes the entire discharge port 16 and the entire communication port 47.
Further, instead of a straight line connecting the discharge port 16 and the communication port 47, a straight line connecting the discharge valve 17 and the communication port 47 may be used.
The circle or ellipse may be substantially a circle or an ellipse, and does not need to be strictly a circle or an ellipse.
The space having the cross section as the cross section is, for example, a space having a shape obtained by extending the cross section straight in the longitudinal direction of the drive shaft 6. That is, the low-stage discharge muffler space 41 is a space formed by, for example, a cylinder (or elliptical column) whose end surface is the circle (or ellipse) and the inner wall of the sealed shell 8.

2) Arrangement of Communication Port 47 The rotational phase (θout1, hereinafter referred to as “communication port phase”) of the rotary piston 12a at the position of the communication port 47 to the intermediate connection flow path 81 is the cylinder suction port 25 of the high-stage compression unit 20. The communication port 47 is arranged so as to be close to the rotation phase of the rotary piston 12a at the position (θs2, hereinafter referred to as “high-stage suction port phase”). That is, the communication port 47 is provided at a position where the rotational phase of the rotary piston 12a is close to the high-stage suction port phase (θs2). That is, the planar arrangement of the communication port 47 is set to a position close to the cylinder suction port 25 of the high-stage compression unit 20.
In FIG. 2, the communication port phase (θout1) is the rotation reference phase (θ ₀ ) and the rotation phase of the rotary piston 12a at the position of the cylinder suction port 15 of the low-stage compression unit 10 (θs1, hereinafter “low-stage suction port phase”). The communication port 47 is provided at a position between the two. That is, the communication port 47 is provided at a position that is a phase between the rotation reference phase (θ ₀ ) and the low-stage suction port phase (θs1) in the rotation phase of the rotary piston 12a.
As a result, the intermediate connecting pipe 84 formed by welding the pipe to the outside of the hermetic shell 8 reduces the rotational phase difference of the rotary piston 12a at both end positions. Therefore, the intermediate connecting pipe 84 is short and bending is reduced. As a result, the intermediate connection flow path 81 including the intermediate connection pipe 84 is short and the flow path is less bent. By making the intermediate connection channel 81 short and a channel with less bending, the pressure loss of the intermediate connection channel 81 can be reduced.

3) Arrangement of the intermediate connecting pipe 84 and the communication port 47 with respect to the compressor suction pipe 1 Rotation phase of the rotary piston 12a at the position of the connecting portion of the compressor suction pipe 1 (θin1, hereinafter referred to as “suction pipe connection phase”) The rotational phase of the rotary piston 12a at the positions of both ends of the intermediate connecting pipe 84 is shifted. Here, both ends of the intermediate connecting pipe 84 are a terminal connection portion of the intermediate connecting pipe 84 and a start end connecting portion of the intermediate connecting pipe 84.
The rotational phase (θin2) of the rotary piston 12a at the position of the terminal connecting portion of the intermediate connecting pipe 84 is hereinafter referred to as “connecting pipe terminal phase”. Further, the rotational phase of the rotary piston 12a at the position of the starting end connection portion of the intermediate connecting pipe 84 is hereinafter referred to as a “connecting pipe start end phase”.
The connecting pipe starting end phase is in principle the same phase as the communication port phase (θout1). Therefore, in other words, the connecting pipe end phase (θin2) and the communication port phase (θout1) are shifted from the suction pipe connecting phase (θin1).

As described in 2), the communication port 47 is provided at a position where the communication port phase (θout1) is close to the high-stage suction port phase (θs2). Here, the high-stage inlet phase (θs2) and the connecting pipe end phase (θin2) can be shifted in phase, but are basically the same in principle. That is, the connecting pipe start end phase (= communication port phase (θout1)) and the connecting pipe end phase (θin2) are close to each other. Therefore, if the connecting pipe start end phase (= communication port phase (θout1)) or the connecting pipe end phase (θin2) overlaps with the suction pipe connection phase (θin1), the intermediate connection pipe 84 and the compressor suction pipe 1 It is necessary to bend and deform the intermediate connecting pipe 84 so that they do not contact each other.
Therefore, the connection pipe start phase (= communication port phase (θout1)) and the connection pipe end phase (θin2) are shifted from the suction pipe connection phase (θin1). That is, the terminal connection part (communication port 47) of the intermediate connection pipe 84 and the terminal connection part of the intermediate connection pipe 84 are provided at positions where the rotational phase of the rotary piston 12a is different from the suction pipe connection phase (θin1). This eliminates the need for bending deformation of the intermediate connecting pipe 84 in order to avoid contact with the compressor suction pipe 1.

The connection portion of the compressor suction pipe 1 is a portion where the compressor suction pipe 1 is connected to the suction muffler 30. In other words, the connection portion of the compressor suction pipe 1 is a position where the compressor suction pipe 1 is inserted into the sealed shell 8.
The terminal connection portion of the intermediate connecting pipe 84 is a position where the intermediate connecting pipe 84 is connected to the flow path on the high-stage compression section 20 side. In other words, the terminal connection portion of the intermediate connecting pipe 84 is a position where the intermediate connecting pipe 84 is connected to the sealed shell 8 and is a position on the high-stage compression section 20 side.
Similarly, the starting end connecting portion of the intermediate connecting pipe 84 is a position where the intermediate connecting pipe 84 is connected to the flow path on the low-stage discharge muffler 40 side. In other words, the starting end connection portion of the intermediate connecting pipe 84 is a position where the intermediate connecting pipe 84 is connected to the sealed shell 8 and is a position on the low-stage discharge muffler 40 side.

In FIG. 2, the connecting pipe start end phase (= communication port phase (θout1)) and the connecting pipe end phase (θin2) are the phase (θin1) and the rotation reference phase (θ ₀ ) at the position of the connecting portion of the compressor suction pipe 1. ) Are provided with a terminal connecting portion of the intermediate connecting pipe 84 and a communication port 47 at a position between them. That is, both ends of the intermediate connecting pipe 84 are provided at positions where the rotational phase of the rotary piston 12a becomes a phase between the phase at the position of the connecting portion of the compressor suction pipe 1 and the rotation reference phase (θ ₀ ).
By making the intermediate connection channel 81 a channel with few bends, the pressure loss of the intermediate connection channel 81 can be reduced.

4) Arrangement of the cylinder suction port 15 and the closed shell connection portion of the compressor suction pipe 1 The low-stage suction port phase (θs1) is shifted from the rotation reference phase (θ ₀ ) with respect to the suction pipe connection phase (θin1). As described in 3), the connecting pipe start phase (= communication port phase (θout1)) and the connecting pipe end phase (θin2) are set between the rotation reference phase (θ ₀ ) and the suction pipe connection phase (θin1). If it arrange | positions to, the suction pipe connection phase ((theta) in1) will leave | separate from a rotation reference phase ((theta) ₀ ). Therefore, the excluded volume (low stage excluded volume) in the low stage compression unit 10 becomes small.
Therefore, the low-stage suction port phase (θs1) is shifted from the rotation reference phase (θ ₀ ) rather than the suction pipe connection phase (θin1). That is, the cylinder suction port 15 is provided at a position where the rotation phase of the rotary piston 12a is closer to the rotation reference phase (θ ₀ ) than the suction pipe connection phase (θin1). Thereby, it can prevent that the exclusion volume (low stage exclusion volume) in the low stage compression part 10 becomes small.

FIG. 4 is a diagram illustrating the relationship between the low-stage discharge muffler specific volume and the specific compressor efficiency of the two-stage rotary compressor according to the first and second embodiments. FIG. 4 shows a case where a heat pump equivalent to the heating rating is operated with a compressor equivalent to 3 horsepower using the R410A refrigerant.
Here, the low-stage discharge muffler specific volume is “the volume of the low-stage discharge muffler space 41 / the low-stage excluded volume”. The specific compressor efficiency is "compressor efficiency / compressor efficiency when the low-stage discharge muffler specific volume is the largest in the conventional two-stage rotary compressor (before improvement of pressure loss in the intermediate connection)" is there.

The conventional two-stage rotary compressor has a higher specific compressor efficiency as the low-stage discharge muffler specific volume is larger.
On the other hand, the two-stage rotary compressor according to the first embodiment has improved compressor efficiency compared to the conventional two-stage rotary compressor. In particular, when the volume of the low-stage discharge muffler space 41 is about five times the low-stage exclusion volume, the compressor efficiency tends to be maximized.
As can be seen from FIG. 4, the volume of the low-stage discharge muffler space 41 needs to have a certain size. This is because the low-stage discharge muffler 40 suppresses the occurrence of pressure pulsation of the fluid ejected from the discharge port 16. However, as described above, the stagnation occurs in the ineffective flow region 49, causing the pressure loss to increase. That is, it is preferable to make the ineffective flow region 49 small while setting the volume of the low-stage discharge muffler space 41 to about five times the low-stage exclusion volume.
For example, while the volume of the low-stage discharge muffler space 41 is about five times the volume of the low-stage exclusion volume, the shape of the low-stage discharge muffler space 41 in the AA cross section is the above-described cross-sectional shape (a region formed by an arc or an elliptic arc). Shape). The volume of the low-stage discharge muffler space 41 is not limited to 5 times the low-stage exclusion volume, and may be about 2-7 times as shown in FIG. Further, the low-stage discharge muffler space 41 is a space including the discharge port 16, the discharge valve 17, and the communication port 47 to the intermediate connection flow path 81 that are the minimum necessary, and the ineffective flow region 49 is made as small as possible. It may be a space.

  As described above, the two-stage rotary compressor according to the first embodiment has a smaller ineffective flow region 49 in the low-stage discharge muffler space 41 than the conventional two-stage rotary compressor. Therefore, the two-stage rotary compressor according to the first embodiment can reduce the pressure loss in the low-stage discharge muffler 40, and the compressor efficiency is high. In the two-stage rotary compressor according to the first embodiment, the suction muffler 30 that has been externally attached to the hermetic shell 8 is disposed in the space created by reducing the ineffective flow region 49. Therefore, the two-stage rotary compressor according to Embodiment 1 can achieve both miniaturization and efficiency.

In the two-stage rotary compressor according to the first embodiment, the intermediate connection flow path 81 has a short length and is a flow path with little bending, so that the pressure loss in the intermediate connection flow path 81 is small.
Further, in the two-stage rotary compressor according to the first embodiment, since the length of the intermediate connection flow path 81 is shortened, the cylinder 11 and the high stage of the low stage compression unit 10 as described in Patent Document 4 are used. A method of shifting the planar arrangement of the compression unit 20 with the cylinder 21 is not used. That is, as in a normal two-stage rotary compressor, the planar arrangement of the cylinder 11 of the low-stage compression unit 10 and the cylinder 21 of the high-stage compression unit 20 remains in the same phase, and the rotary piston 12a and the rotary piston 22a are in the same phase. The position can be shifted by 180 degrees with respect to the drive shaft 6. Therefore, it is possible to obtain an effect of canceling out torque fluctuations of the low-stage compression unit 10 and the high-stage compression unit 20 in opposite phases, which is a feature of a normal two-stage rotary compressor.

  In the description of FIG. 4, the effect is described by using the R410A refrigerant. However, natural effects such as HFC refrigerants (R22, R407, etc.) other than the R410A refrigerant, HC refrigerants (isobutane, propane), and CO2 refrigerants are used. The same effect can be obtained by using a refrigerant or a low GWP refrigerant such as HFO1234yf.

Embodiment 2. FIG.
In the second embodiment, the arrangement of the suction muffler 30 and the low-stage discharge muffler 40 different from the first embodiment will be described.

5 is an AA cross-sectional view of the two-stage rotary compressor of FIG. 1 according to the second embodiment. In FIG. 5, some constituent elements that are not originally visible in the sectional view are indicated by broken lines.
The region of the low-stage discharge muffler seal portion 43 of the low-stage discharge muffler 40 shown in FIG. 2 is formed so as to surround the lower bearing portion 61. The region of the low-stage discharge muffler seal portion 43 of the low-stage discharge muffler 40 shown in FIG. 5 does not include the lower bearing portion 61, but is formed by a closed curve including the cylinder discharge port 16, the discharge valve 17, the recessed installation portion 18, and the communication port 47. did. That is, the low-stage discharge muffler 40 shown in FIG. 5 is shown in FIG. 2 in that the region surrounded by the low-stage discharge muffler seal portion 43 is limited to the range including the discharge port 16, the discharge valve 17, and the concave installation portion 18 of the cylinder 11. Different from the low-stage discharge muffler 40.
Even if the suction muffler 30 and the low-stage discharge muffler 40 are configured as shown in FIG. 5, the same effect as when the suction muffler 30 and the low-stage discharge muffler 40 are configured as shown in FIG. 2 can be obtained. it can.

6 is a cross-sectional view taken along line AA of the two-stage rotary compressor of FIG. 1 according to the second embodiment. In FIG. 6, some constituent elements that are not originally visible in the sectional view are indicated by broken lines.
In FIG. 6, the low-stage discharge muffler space 41 is a region in contact with the discharge port side surface portion 62 of the lower support member 60 and does not include the lower bearing portion 61, and is included in the ring-shaped (donut-shaped) region of the drive shaft 6. It was set as the predetermined angle range centering on the shaft center 6d. In particular, in FIG. 6, the low-stage discharge muffler space 41 is formed in a region limited to a range including the discharge port 16, the discharge valve 17, the discharge valve recessed portion 18, and the communication port 47.
On the other hand, the suction muffler space is a drive that excludes the low-stage discharge muffler space 41 in a ring-shaped (donut-shaped) region that is in contact with the discharge port side surface portion 62 of the lower support member 60 and does not include the lower bearing portion 61. A predetermined angle range centered on the axis 6d of the shaft 6 was set.
Even if the suction muffler 30 and the low-stage discharge muffler 40 are configured as shown in FIG. 6, the same effect as when the suction muffler 30 and the low-stage discharge muffler 40 are configured as shown in FIG. 2 can be obtained. it can.

  The seal portions 33 and 43 shown in FIGS. 2 and 5 are formed by connecting smooth curves. Therefore, O-rings can be used for the seal portions 33 and 43 shown in FIGS. On the other hand, the seal parts 33 and 43 shown in FIG. 6 were formed in a shape including a straight line. Therefore, it is necessary to use metal packing instead of an O-ring for the seal portions 33 and 43 shown in FIG. By using metal packing for the seal portions 33 and 43, the region formed by the seal portions 33 and 43 can be formed into a free shape.

7 is a cross-sectional view taken along line AA of the two-stage rotary compressor of FIG. 1 according to the second embodiment. In FIG. 7, some components that are not originally visible in the sectional view are indicated by broken lines.
2 and 5, the low-stage discharge muffler space 41 is formed inside the suction muffler space 31 surrounded by the suction muffler seal part 33 by forming a closed curve with the low-stage discharge muffler seal part 43. On the other hand, in FIG. 7, the low-stage discharge muffler space 41 is formed outside the suction muffler space 31 surrounded by the suction muffler seal part 33 by forming a closed curve with the low-stage discharge muffler seal part 43.
Even if the suction muffler 30 and the low-stage discharge muffler 40 are configured as shown in FIG. 7, the same effects as those obtained when the suction muffler 30 and the low-stage discharge muffler 40 are configured as shown in FIG. 2 can be obtained. it can.

FIG. 4 shows the relationship between the low-stage discharge muffler specific volume and the specific compressor efficiency for the two-stage rotary compressor including the suction muffler 30 and the low-stage discharge muffler 40 shown in FIG. In FIG. 7, the phase (θout1) of the communication port 47 is not intentionally placed near the phase of the cylinder suction port 25. For this reason, the intermediate connecting pipe 84 becomes longer and the pressure loss becomes larger.
As shown in FIG. 4, the two-stage rotary compressor having the configuration shown in FIG. 7 has higher compressor efficiency than the conventional two-stage rotary compressor. On the other hand, the two-stage rotary compressor having the configuration shown in FIG. 7 has the communication port phase (θout1) provided on the opposite side of the rotation direction of the rotary piston 12a with respect to the rotation reference phase (θ ₀ ). Since the intermediate connecting pipe 84 is long and the pressure loss is large, the effect of improving the compressor efficiency is inferior to that of the two-stage rotary compressor according to the first embodiment.
However, the two-stage rotary compressor having the configuration shown in FIG. 7 is similar to the two-stage rotary compressor according to the first embodiment in that the ineffective flow region 49 in the low-stage discharge muffler 40 is reduced, and the The pressure loss in the stage discharge muffler 40 is reduced, and the compressor efficiency is increased. In particular, as in the case of the first embodiment, when the volume of the low-stage discharge muffler space 41 is about five times the low-stage exclusion volume, the compressor efficiency tends to be maximized.
The volume of the low-stage discharge muffler space 41 is not limited to 5 times the low-stage exclusion volume, and may be about 3 to 8 times as shown in FIG. Further, in the two-stage rotary compressor having the configuration shown in FIG. 7, the suction muffler 30 can be appropriately arranged inside the hermetic shell 8, similarly to the two-stage rotary compressor according to the first embodiment. Is possible. Therefore, the two-stage rotary compressor having the configuration shown in FIG. 7 can achieve both miniaturization and efficiency, as with the two-stage rotary compressor according to the first embodiment.

Embodiment 3 FIG.
In the first embodiment, the two-stage rotary compressor in which the intermediate connection flow path 81 is configured using the intermediate connection pipe 84 that passes outside the sealed shell 8 has been described. In the third embodiment, a two-stage rotary compressor in which the entire intermediate connection channel 81 is disposed inside the hermetic shell 8 will be described.

FIG. 8 is a cross-sectional view showing the overall configuration of the two-stage rotary compressor according to the third embodiment. 9 is an AA cross-sectional view of the two-stage rotary compressor of FIG. 8 according to the third embodiment. In FIG. 9, some components that are not originally visible in the sectional view are indicated by broken lines.
The two-stage rotary compressor according to the third embodiment does not include the intermediate connection pipe 84 in which the intermediate connection flow path 81 is connected to the outside of the sealed shell 8. That is, the entire intermediate connection channel 81 is provided inside the sealed shell 8. In this respect, the two-stage rotary compressor according to the third embodiment is different from the two-stage rotary compressor according to the first embodiment.
The refrigerant flow in the two-stage rotary compressor according to the third embodiment is basically the same as the refrigerant flow in the two-stage rotary compressor according to the first embodiment. However, the refrigerant discharged into the low-stage discharge muffler space 41 passes through the intermediate connection flow path 81 connected to the cylinder suction port 25 through the inside of the closed shell 8 ((6) in FIG. 8), and the high-stage compression section. It differs in that it is sucked into 20 cylinders 21.
Also in the two-stage rotary compressor according to the third embodiment, a method of reducing the pressure loss of the intermediate connecting portion by reducing the ineffective flow region 49 can be applied. Therefore, similarly to the two-stage rotary compressor according to the first embodiment, the two-stage rotary compressor according to the third embodiment can achieve both reduction in size and efficiency.
In particular, in the two-stage rotary compressor according to the third embodiment, the entire intermediate connection flow path 81 passes through the inside of the hermetic shell 8, so that the flow path is more than that of the two-stage rotary compressor according to the first embodiment. The length can be shortened. Therefore, the pressure loss can be further reduced and the size can be reduced.

Embodiment 4 FIG.
In the first embodiment, the two-stage rotary compressor in which the low-stage compression unit 10 is disposed below the intermediate partition plate 5 has been described. In the fourth embodiment, a two-stage rotary compressor in which the low-stage compression unit 10 is disposed on the upper side of the intermediate partition plate 5 will be described.

FIG. 10 is a cross-sectional view showing the overall configuration of the two-stage rotary compressor according to the fourth embodiment. FIG. 11 is an AA cross-sectional view of the two-stage rotary compressor of FIG. 10 according to the fourth embodiment. In addition, in FIG. 11, the one part component which cannot be seen in sectional drawing originally is shown with a broken line, and it is the figure which assumes that the low stage compression part 10 is a swing piston type compressor.
In the first embodiment, as an example, the description has been made assuming that the low-stage compression unit 10 is a rotary piston type compressor. Therefore, FIG. 2 is a diagram assuming that the low-stage compression unit 10 is a rotary piston type compressor. In the first embodiment, the position of the vane 14a is set as the rotation reference phase (θ ₀ ).
On the other hand, in the fourth embodiment, as another example, it is assumed that the low stage compression unit 10 is a swing piston type compressor. That is, in the fourth embodiment, in the low-stage compression unit 10, the swing piston 12b in the cylinder 11 swings in the cylinder 11 with the swing bush 14c as a fulcrum through the blade 14b by the rotation of the drive shaft. However, the eccentric position that minimizes the gap with the inner wall of the cylinder 11 is rotated counterclockwise. A stationary point position of a blade 14b (an example of a partition member) that partitions the inside of the cylinder into a compression chamber and a suction chamber is defined as a rotation reference phase θ ₀ , and a low-stage piston eccentric direction position is determined from the rotation reference phase θ ₀ , the cylinder suction port phase, The refrigerant is compressed by rotating in the order of the low-stage discharge port phase.

The refrigerant flow in the two-stage rotary compressor according to the fourth embodiment is the same as the refrigerant flow in the two-stage rotary compressor according to the first embodiment until the high-stage compression unit 20 compresses the refrigerant to a high pressure. It is. Then, the flow of the refrigerant | coolant after compressed to the high pressure in the high stage compression part 20 is demonstrated.
The refrigerant compressed to a high pressure is discharged into a high-stage discharge muffler space 51 formed inside the high-stage discharge muffler 50 ((8) in FIG. 10). The refrigerant discharged into the high-stage discharge muffler space 51 passes through the high-stage discharge flow path 58 from the communication port 57 ((9) in FIG. 10), and inside the hermetic shell 8, the low-stage compression unit 10 and the motor unit 9. (10 in FIG. 10). Then, the refrigerant is discharged to the external refrigerant circuit through the compressor discharge pipe 2.

  Also in the two-stage rotary compressor according to the fourth embodiment, the method of reducing the pressure loss of the intermediate coupling portion of the first embodiment can be applied. That is, even in the two-stage rotary compressor in which the low-stage compression unit 10 is disposed on the upper side of the intermediate partition plate 5 and the high-stage compression unit 20 is disposed on the lower side of the intermediate partition plate 5, Similar to the two-stage rotary compressor, it is possible to achieve both miniaturization and efficiency. Similarly, even if it is a two-stage rotary compressor using a swing piston type compressor for the low-stage compressor 10 (and the high-stage compressor 20), the two-stage rotary compressor according to the first embodiment Similarly, it is possible to achieve both miniaturization and efficiency.

Embodiment 5 FIG.
In the above embodiment, the high-pressure shell type two-stage rotary compressor that allows high-pressure refrigerant to pass inside the sealed shell 8 is used. In the fifth embodiment, an intermediate pressure shell type two-stage rotary compressor in which an intermediate pressure refrigerant is passed inside the hermetic shell 8 will be described.

FIG. 12 is a cross-sectional view showing the overall configuration of the two-stage rotary compressor according to the fifth embodiment. 13 is an AA cross-sectional view of the two-stage rotary compressor of FIG. 12 according to the fifth embodiment. In FIG. 13, some components that are not originally visible in the cross-sectional view are indicated by broken lines.
The refrigerant flow in the two-stage rotary compressor according to the fifth embodiment is the same as the refrigerant flow in the two-stage rotary compressor according to the first embodiment until the low-stage compression unit 10 compresses the refrigerant to the intermediate pressure. It is the same. Therefore, the flow of the refrigerant after being compressed to the intermediate pressure by the low stage compression unit 10 will be described.
The refrigerant compressed to the intermediate pressure is discharged from the discharge port 16 to the low-stage discharge muffler space 41 by opening the discharge valve 17 ((5) in FIG. 12). The refrigerant discharged to the low-stage discharge muffler space 41 is discharged from the communication port 47 to the inside of the sealed shell 8 ((6) in FIG. 12). Then, the refrigerant discharged to the inside of the sealed shell 8 passes through the intermediate connection channel 81 ((7) in FIG. 12) and is sucked into the cylinder 21 of the high-stage compression unit 20 ((8 in FIG. 12). )). Next, the refrigerant sucked into the cylinder 21 is compressed to a high pressure by the high stage compression unit 20 and then discharged to a high stage discharge muffler space 51 formed inside the high stage discharge muffler 50 (FIG. 12). (9)). The refrigerant discharged to the high-stage discharge muffler space 51 is discharged to the external refrigerant circuit through the compressor discharge pipe 2.

  Also in the two-stage rotary compressor according to the fifth embodiment, the method of reducing the pressure loss of the intermediate coupling portion of the first embodiment can be applied. That is, even in the case of the intermediate pressure shell type two-stage rotary compressor, it is possible to achieve both miniaturization and efficiency improvement in the same manner as the two-stage rotary compressor according to the first embodiment.

  In the above embodiment, the case of the rotary piston type compressor and the case of the swing piston type compressor has been described as the rotary compressor. However, the present invention is not limited to this, and the method of reducing the pressure loss of the intermediate connecting portion according to the first embodiment can be applied to various rotary compressors such as a sliding vane type compressor. And even if it is a case where it applies to a sliding vane type compressor etc., the same effect as a rotary piston type compressor explained by the above embodiment is acquired.

Embodiment 6 FIG.
In the sixth embodiment, a heat pump heating and hot water supply system 90 that is an example of using the multistage rotary compressor (two-stage rotary compressor) described in the above embodiment will be described.

  FIG. 14 is a schematic diagram showing a configuration of a heat pump type heating and hot water supply system 90 according to the sixth embodiment. The heat pump type hot water supply system 90 includes a compressor 91, a first heat exchanger 92, a first expansion valve 93, a second heat exchanger 94, a second expansion valve 95, a third heat exchanger 96, a main refrigerant circuit 97, A water circuit 98 and a heating / hot water supply device 100 are provided. Here, the compressor 91 is the multistage rotary compressor (here, a two-stage rotary compressor) described in the above embodiment.

The heat pump unit 101 includes a compressor 91, a first heat exchanger 92, a first expansion valve 93,
A part of the refrigerant branches off at a branch point 102 between the main refrigerant circuit 97 in which the second heat exchanger 94 is sequentially connected, the first heat exchanger 92, and the first expansion valve 93, and the second expansion valve 95, It is composed of an injection circuit 99 that flows through the three heat exchangers 96 and returns the refrigerant to the intermediate connecting portion 80 of the compressor 91, and operates as an economizer cycle having excellent efficiency.

In the first heat exchanger 92, heat is exchanged between the refrigerant compressed by the compressor 91 and the liquid (here, water) flowing through the water circuit 98. Here, heat is exchanged in the first heat exchanger 92, whereby the refrigerant is cooled and the water is warmed. The first expansion valve 93 expands the refrigerant heat-exchanged by the first heat exchanger 92. The second heat exchanger 94 performs heat exchange between the expanded refrigerant and air in accordance with the control of the first expansion valve 93. Here, the heat is exchanged in the second heat exchanger 94, whereby the refrigerant is warmed and the air is cooled. Then, the warmed refrigerant is sucked into the compressor 91.
Further, a part of the refrigerant heat-exchanged by the first heat exchanger 92 branches at the branch point 102 and expands at the second expansion valve 95, and the third heat exchanger 96 follows the control of the second expansion valve. The expanded refrigerant and the refrigerant cooled by the first heat exchanger 92 undergo internal heat exchange and are injected into the intermediate connection portion 80 of the compressor 91. In this manner, the heat pump unit 101 including the economizer means that increases the cooling capacity and the heating capacity by the pressure reducing effect of the refrigerant flowing through the injection circuit 99 is operated.
On the other hand, as described above, in the water circuit 98, the water is warmed by heat exchange in the first heat exchanger 92, and the warmed water flows to the heating / hot water supply device 100 and is used for hot water supply and heating. Is done. The hot water supply water may not be water that is heat-exchanged by the first heat exchanger 92. That is, the water flowing through the water circuit 98 and the water for hot water supply may be further heat-exchanged by a water heater or the like.

The multistage rotary compressor according to the present invention is excellent in single compressor efficiency and miniaturization. Furthermore, when this is mounted on the heat pump heating / hot water supply system 90 described in the present embodiment and an economizer cycle is configured, a configuration superior in efficiency can be realized. It is also superior in miniaturization.
Here, the heat pump type heating hot water supply system (ATW (Air To Water) system) that heats water with the refrigerant compressed by the multistage rotary compressor described in the above embodiment has been described. However, the present invention is not limited to this, and a vapor compression refrigeration cycle in which a gas such as air is heated or cooled with the refrigerant compressed by the multistage rotary compressor described in the above embodiment can also be formed. That is, a refrigeration air conditioner can also be constructed by the multistage rotary compressor described in the above embodiment. The refrigerating and air-conditioning apparatus using the multistage rotary compressor of the present invention is excellent in miniaturization and high efficiency.

  DESCRIPTION OF SYMBOLS 1 Compressor suction pipe, 2 Compressor discharge pipe, 3 Lubricating oil storage part, 5 Intermediate partition plate, 6 Drive shaft, 8 Sealing shell, 9 Motor part, 10 Low stage compression part, 20 High stage compression part, 11, 21 Cylinder, 11a, 21a Cylinder chamber, 12a, 22a Rotating piston, 12b, 12b Oscillating piston, 14a, 24a Vane, 14b, 24b Blade, 14c Oscillating bush, 15, 25 Cylinder suction port, 16, 26 Discharge port, 17 , 27 Discharge valve, 18, 28 Discharge valve concave installation part, 30 Suction muffler, 31 Suction muffler space, 32 Suction muffler container, 33 Suction muffler seal part, 34 Liquid storage part, 36 Suction muffler inlet, 37 Suction muffler outlet, 38 Narrow tube , 39 Drilled holes, 40 Low-stage discharge muffler, 41 Low-stage discharge muffler space, 42 Low-stage discharge muffler container, 43 Low-stage discharge muffler seal part, 47 communication port, 49 Invalid flow area, 50 High-stage discharge muffler, 51 High-stage discharge muffler space, 52 High-stage discharge muffler container, 53 High-stage discharge muffler seal part, 57 Communication port, 58 High-stage discharge Flow path, 60 Lower support member, 61 Lower bearing portion, 62 Discharge port side surface portion, 70 Upper support member, 71 Upper bearing portion, 72 Discharge port side surface portion, 80 Intermediate connection portion, 81 Intermediate connection flow channel, 82 Refrigerant injection port , 84 Intermediate connecting pipe, 90 Heat pump type hot water supply system, 91 Compressor, 92 1st heat exchanger, 93 1st expansion valve, 94 2nd heat exchanger, 95 2nd expansion valve, 96 3rd heat exchanger, 97 Main refrigerant circuit, 98 Water circuit, 99 Injection circuit, 100 Heating hot water supply device, 101 Heat pump unit, 102 Branch point, 140 Stage discharge muffler, 141 low-stage discharge muffler space 142 low-stage discharge muffler chamber, 143 low-stage discharge Mafurashiru unit, 147 communication port, 149 disables the flow area.

Claims (7)

A sealed shell;
A first compression unit provided inside the hermetic shell and compressing the refrigerant;
A second compression unit provided inside the hermetic shell and stacked on the first compression unit, and further compresses the refrigerant compressed by the first compression unit;
The refrigerant flows in from the outside of the hermetic shell , separates the flowing refrigerant into gas refrigerant and liquid refrigerant, temporarily stores the separated liquid refrigerant, and flows the separated gas refrigerant out to the first compression unit. A suction muffler that forms a suction muffler space;
A discharge muffler that forms a discharge muffler space in which the refrigerant is discharged from the first compression unit and flows out to the second compression unit;
The suction muffler and the discharge muffler are at least partially arranged in parallel in the stacking direction of the first compression unit and the second compression unit, and the first compression unit and the second compression unit Laminated and provided inside the sealed shell,
The discharge muffler forms, as the discharge muffler space, a predetermined space including a discharge port through which the refrigerant compressed by the first compression unit is discharged and a communication port through which the refrigerant flows out to the second compression unit,
The suction muffler is a space in a range where the discharge muffler space is formed in the stacking direction, and forms at least a part of the space other than the space where the discharge muffler space is formed as the suction muffler space. A featured multistage compressor. In the first compression section, an inside of a cylinder partitioned by a partition member into a compression chamber and a suction chamber is formed between a suction port through which the refrigerant flows from the suction muffler and a discharge port through which the refrigerant is discharged to the discharge muffler. The eccentric position of the piston rotates to compress the refrigerant,
The communication port is located at a position where the rotational phase of the eccentric position of the piston is a phase between the rotational reference phase and the phase of the suction port when the position of the partition member is a rotational reference phase. The multistage compressor according to claim 1, wherein the multistage compressor is provided. A compressor suction pipe having one end provided outside the sealed shell and the other end connected to the suction muffler;
An intermediate connecting pipe provided outside the sealed shell, connected at one end to the flow path communicating with the communication port, and connected at the other end to the flow path communicated with the second compression section;
In the suction muffler, the refrigerant flows through the compressor suction pipe,
The first compression unit is configured such that the eccentric position of the piston rotates inside the cylinder, compresses the refrigerant flowing in from the suction muffler, and discharges the refrigerant to the discharge muffler.
In the discharge muffler, the discharged refrigerant flows out to the second compression part through the intermediate connecting pipe,
The both ends of the intermediate connecting pipe are connected at positions where the rotational phase of the eccentric position of the piston is different from the phase at the position where the compressor suction pipe is connected to the hermetic shell. Item 3. The multistage compressor according to Item 1 or 2. The first compression unit is disposed inside a cylinder partitioned by a partition member into a compression chamber and a suction chamber between a suction port through which the refrigerant flows from the suction muffler and a discharge port through which the refrigerant is discharged to the discharge muffler. The eccentric position of the piston rotates to compress the refrigerant,
The suction port of the first compression unit has a rotational phase of an eccentric position of the piston at a position where the compressor suction pipe is connected to the sealed shell when the position of the partition member is a rotation reference phase. 4. The multistage compressor according to claim 3, wherein the multistage compressor is provided at a position closer to the rotation reference phase than the rotation reference phase. Provided inside the hermetic shell, an intermediate connecting flow path for connecting the discharge muffler and the second compression part,
The multistage compressor according to claim 1 or 2, wherein the discharge muffler causes the refrigerant to flow out to the second compression section through the intermediate connection flow path. The discharge muffler is formed by a circular arc whose diameter is a straight line connecting the discharge port and the communication port or an elliptical elliptic arc whose long side is the straight line in a cross section perpendicular to the stacking direction. The multistage compressor according to any one of claims 1 to 5, wherein a space having a cross section as a section is formed as the discharge muffler space. A refrigerating and air-conditioning apparatus comprising the multistage compressor according to any one of claims 1 to 6.

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