JP2007224854A - Compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compressor including a compression mechanism reduced in mechanical loss. <P>SOLUTION: The compressor includes an expansion mechanism 1 and the compression mechanism 41. The expansion mechanism 1 is provided with a stator 10 forming a space 10A therein, a cylindrical rotor 20 rotating in a space 10A in the stator 10, a shaft 40 driving and rotating the rotor 20, a vane 22 sliding in a vane groove 21 included in the rotor 20, an end plate 30 blocking the end surface of the rotor 20 and the end surface of the stator 10, a supply port 12 supplying gas to an expansion space 11 formed between the stator 10 and the rotor 20 and a delivery port 31 delivering gas from the expansion space 11. The rotor 20 and the shaft 40 are joined by spline and the shaft 40 is used as a drive shaft of the compression mechanism 41. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a compressor having an expansion mechanism and a compression mechanism.

Currently, the use of carbon dioxide as a refrigerant in a refrigeration apparatus is being studied, but from the viewpoint of energy efficiency, the use of an expander as an expansion apparatus is being studied.
Since the expansion mechanism section and the compression mechanism section are structurally common, a structure that has been used as a conventional compression mechanism section can be used as the expansion mechanism section.

By the way, when the compressor and the expander are compared, in the same refrigeration cycle apparatus, the structure conventionally used as the compression mechanism unit is expanded in the same refrigeration cycle apparatus, although the axial torque of the expander is smaller. When used as a machine, the loss ratio of the expander becomes relatively large.
In addition, it is conceivable to connect the compressor and the expander coaxially, but in the case of connecting with an integral shaft, the shaft core of the compression mechanism and the expansion mechanism, the stator and the rotor constituting the electric motor It is difficult to arrange and assemble the same in the same container. A method of connecting the shaft after assembling the compression mechanism portion and the expansion mechanism portion separately is also conceivable, but it is difficult to ensure the reliability of the joint portion.

Then, an object of this invention is to provide the compressor which has an expansion mechanism part with few mechanical losses.
Another object of the present invention is to provide a compressor that can be easily assembled in a compressor including an expansion mechanism and a compression mechanism.

The compressor according to the first aspect of the present invention is a compressor having an expansion mechanism portion and a compression mechanism portion, wherein the expansion mechanism portion includes a stator that forms a space therein, and the space inside the stator. A rotating cylindrical rotor, a shaft for rotationally driving the rotor, a vane sliding in a vane groove of the rotor, an end plate for sealing the end face of the rotor and the end face of the stator, and the stator A supply port for supplying gas to an expansion space formed between the rotor and the rotor, and a discharge port for discharging the gas from the expansion space, the rotor and the shaft being spline-coupled, The drive shaft of the compression mechanism is used.
According to a second aspect of the present invention, in the compressor according to the first aspect, the rotor is provided so as to be movable in the axial direction with respect to the shaft.
According to a third aspect of the present invention, in the compressor according to the first aspect, the space formed inside the stator has an elliptical shape in a plan view, and is provided on a surface opposite to the minor axis side of the elliptical shape. A circular arc portion concentric with the rotor is formed.
According to a fourth aspect of the present invention, in the compressor according to the third aspect, the plurality of vanes are arranged such that at least one of the vanes is arranged in the arc portion during operation of the rotor. Features.
According to a fifth aspect of the present invention, in the compressor according to the first aspect, a plurality of sets of the supply port and the discharge port are provided, the supply ports are arranged symmetrically, and the discharge ports are arranged. Are arranged symmetrically about the axis.

  According to the present invention, it is possible to realize a compressor that has a low mechanical loss and can be easily assembled.

In the compressor according to the first embodiment of the present invention, the expansion mechanism section includes a stator that forms a space therein, a cylindrical rotor that rotates in the space inside the stator, a shaft that rotationally drives the rotor, and the rotor A vane that slides in the vane groove, an end plate that seals the end face of the rotor and the end face of the stator, a supply port that supplies gas to the expansion space formed between the stator and the rotor, and the expansion space And a discharge port for discharging gas from the rotor, the rotor and the shaft are splined, and the shaft is the drive shaft of the compression mechanism. According to the present embodiment, since there is a clearance between the rotor and the shaft, mechanical loss in the expansion mechanism can be reduced, and the compression mechanism and the expansion mechanism are connected by the shaft. In addition, the assembly work can be easily performed.
In the compressor according to the first embodiment, the second embodiment of the present invention is such that a rotor is provided so as to be movable in the axial direction with respect to the shaft. According to the present embodiment, since the thrust force from the rotor to the shaft does not work, the mechanical loss in the expansion mechanism can be reduced. Further, since the rotor can move in the axial direction, if the pressure balance between both end faces of the rotor is balanced, the clearances at both end faces become equal, and leakage through the end face of the rotor can be minimized.
According to the third embodiment of the present invention, in the compressor according to the first embodiment, the space formed inside the stator is elliptical in a plan view, and the elliptical minor surface is opposed to the opposite surface. A circular arc portion concentric with the rotor is formed. According to the present embodiment, since the rotor and the shaft are splined, the rotor is centered on the center of the space inside the stator, so that the clearance between the arc portion and the rotor can be reduced. In addition, when the rotor and the shaft are rigidly joined, the rotor outer peripheral surface comes into contact with the inner peripheral surface of the space due to the inclination of the shaft, but in this embodiment, the rotor and the shaft are spline-coupled. The rotor is not affected by the inclination of the shaft, and the outer peripheral surface of the rotor is not in contact with the inner peripheral surface of the space, so that the clearance between the arc portion and the rotor can be reduced. In the present embodiment, since the rotor and the shaft are spline-coupled, the rotor can move in the axial direction. Therefore, if the pressure balance between both end faces of the rotor is balanced, the clearances at both end faces become equal, and the rotor Leakage through the end face can be minimized. By increasing the clearance between the cylinder and the rotor, according to the present embodiment, the sliding friction of the rotor with respect to the stator can be reduced, the rotor can be easily started, and the expansion mechanism The mechanical loss in the section can be reduced.
According to a fourth embodiment of the present invention, in the compressor according to the third embodiment, a plurality of vanes are arranged so that at least one vane is arranged in an arc portion during operation of the rotor. . According to the present embodiment, refrigerant leakage at the arc portion can be prevented.
In the compressor according to the first embodiment, the fifth embodiment of the present invention includes a plurality of sets of supply ports and discharge ports, and the supply ports are arranged symmetrically with respect to each other. Axially arranged. According to the present embodiment, since the pressure is applied symmetrically to the rotor, the rotor can always be held at an appropriate position with respect to the stator.

A compressor according to an embodiment of the present invention will be described below.
FIGS. 1 to 4 are plan views of essential parts of the expansion mechanism according to the present embodiment, FIG. 1 is a plan view showing a supply completion state of one expansion chamber, and FIG. 2 is that the next expansion chamber is in the supply stroke. FIG. 3 is a plan view showing a state immediately before the end of the supply stroke of the expansion chamber, and FIG. 4 is a plan view showing a supply completion state of the expansion chamber. FIG. 5 is a side sectional view of the expansion mechanism, and FIG. 6 is a side sectional view of a compressor having the expansion mechanism.

First, the configuration of the expansion mechanism according to this embodiment will be described.
As shown in FIGS. 1 to 4, the expansion mechanism portion 1 according to this embodiment includes a stator 10 that forms a space 10 </ b> A therein, and a cylindrical rotor 20 that rotates in the space 10 </ b> A inside the stator 10. Yes. Here, the space 10A formed inside the stator 10 is formed in an elliptical shape in plan view, and a concentric circular arc portion 10B that is concentric with the rotor 20 is formed on the opposing surface on the minor axis side of the elliptical shape. ing. The radius of curvature of the arc portion 10B is smaller than the radius of curvature on the minor axis side of the elliptical shape, and the minimum gap between the space 10A formed on the minor axis side and the rotor 20 is predetermined by forming the arc portion 10B. The clearance is secured.
An expansion space 11 is formed between the stator 10 and the rotor 20. The rotor 20 has a plurality of vane grooves 21 formed radially. In the vane grooves 21, a plurality of vanes 22 that slide in the vane grooves 21 are arranged.
These vanes 22 divide the expansion space 11 into a plurality of expansion chambers 11A and 11B. In the figure, 10 expansion chambers 11A, 11B... Are divided by 10 vanes 22. In the present embodiment, the ten vanes 22 are configured so that at least one vane 22 is arranged in the arc portion 10 </ b> B during the operation of the rotor 20.
The stator 10 is provided with a supply port 12 for supplying gas to the expansion chambers 11A and 11B.
Between each adjacent vane 22, the rotor side communication path 23 is arrange | positioned. The rotor side communication path 23 is formed by a groove having a predetermined length formed on one end face of the rotor 20, and is arranged radially with the vane groove 21 with respect to the center of the rotor 20. The length of the rotor side communication path 23 is shorter than the length of the vane groove 21.

The discharge port 31 and the end plate side communication path 32 shown in FIGS. 1 to 4 are provided in the end plate 30 shown in FIG. The discharge port 31 is a space for discharging gas from the expansion space 11. The end plate side communication path 32 is formed by an arc-shaped groove having a predetermined length.
In addition, the shaft 40 is arrange | positioned in the center hole of the rotor 20, and the rotor 20 and the shaft 40 are spline-coupled. Note that the spline coupling in this embodiment is such that the rotor 20 and the shaft 40 are engaged only in the rotational direction, and can freely slide in the axial direction. Therefore, it is preferable that the spline length of the shaft 40 is longer than the spline length of the rotor 20 and the rotor 20 is provided so as to be movable in the axial direction with respect to the shaft 40.
In this embodiment, two sets of the supply port 12 and the discharge port 31 are provided, the supply ports 12 are arranged symmetrically, and the discharge ports 31 are arranged symmetrically. As described above, by arranging the supply port 12 and the discharge port 31 symmetrically, the pressures of the opposing expansion / expansion chambers 11A, 11B,... Are equalized, and the clearance between the rotor 20 and the shaft 40 is uniformly generated. The mechanical friction between the rotor 20 and the shaft 40 can be reduced. Even when three or more sets of the supply port 12 and the discharge port 31 are provided, the supply port 12 is arranged symmetrically with respect to the axis, and the discharge port 31 is arranged symmetrically with respect to the rotor 20. Mechanical friction with the shaft 40 can be reduced.

As shown in FIG. 5, both end faces of the rotor 20 and both end faces of the stator 10 are sealed by a pair of end plates 30. The end plate side communication passage 32 is formed on the end face of the end plate 30, and a passage 34 through which the gas guided to the supply port 12 communicates is formed in the end plate 30. The end plate side communication passage 32 and the passage 34 communicate with each other. The end surface of the end plate 30 in which the end plate side communication path 32 is formed faces the end surface of the rotor 20 in which the rotor side communication path 23 is formed.
One end plate 30 is formed with an annular groove 33, and this annular groove 33 communicates with the center side end of the vane groove 21 shown in FIGS. 1 to 4. High pressure gas or high pressure lubricating oil is supplied to the annular groove 33 to apply a back pressure to the vane 22. In the expansion mechanism portion according to the present embodiment, the space in the stator 10 has an elliptical shape, and the supply port 12 and the discharge port 31 are provided at symmetrical positions.

As shown in FIG. 6, the expansion mechanism portion 1 according to the present embodiment is disposed in a sealed container 42 together with the compression mechanism portion 41. In addition, this kind of compressor comprises a refrigerating-cycle apparatus with a heat radiator and an evaporator. As this refrigeration cycle apparatus, it is preferable to use carbon dioxide as a refrigerant and to operate in a supercritical region on the high pressure side.
An electric mechanism 43 is also provided in the sealed container 42. The compression mechanism unit 41 is disposed above the sealed container 42, and the electric mechanism unit 43 is disposed between the compression mechanism unit 41 and the expansion mechanism unit 1. A suction pipe 44 and a discharge pipe 45 are provided on the top of the sealed container 41. An oil reservoir 46 for accumulating lubricating oil is provided in the lower part of the sealed container 42.
The compression mechanism unit 41 includes a fixed scroll part 41a and a turning scroll part 41b, and both parts mesh with each other to form a plurality of compression chambers. That is, the fixed scroll component 41a is configured with a spiral fixed spiral wrap rising from a fixed end plate, and the orbiting scroll component 41b is configured with a spiral swirl spiral wrap rising from a swing end plate. The compression chamber is formed by meshing the swirl spiral wrap and the fixed spiral wrap between the fixed mirror plate and the swivel mirror plate.
The orbiting scroll component 41b is constrained to rotate by the rotation restraint mechanism 47 and revolves along a circular orbit. The compression chamber moves while changing the volume by the orbiting operation of the orbiting scroll component 41b. A back pressure space 48 is provided on the back of the end plate of the orbiting scroll component 41b. In this back pressure space 48, a sliding partition ring 50 is arranged in an annular groove provided in the bearing member 49, and the back pressure space 48 is divided into two by this sliding partition ring 50. A high discharge pressure is applied to one inner region 48b divided by the sliding partition ring 50. A predetermined intermediate pressure between the suction pressure and the discharge pressure is applied to the outer region 48a.
The electric mechanism unit 43 includes a stator 43a and a rotor 43b. The stator 43 a is fixed to the sealed container 42, and the rotor 43 b is fixed to the shaft 40.
The shaft 40 engages with the orbiting scroll component 41b at the upper end portion thereof, causes the orbiting scroll component 41b to perform an orbiting operation, and causes the expansion mechanism portion 1 to rotate at the lower end portion thereof.

Next, the operation of the expansion mechanism unit according to this embodiment will be described.
The expansion mechanism according to this embodiment expands the gas supplied from the supply port 12 in the expansion chambers 11A and 11B and discharges the gas from the discharge port 31. When the gas supplied from the supply port 12 is a high-pressure gas, the rotor 20 is rotated by the expansion action of the gas. When the gas supplied from the supply port 12 is expanded, the rotor 20 is rotated.
FIG. 1 shows a state where the supply stroke of the expansion chamber 11A is completed. The rear end side of the expansion chamber 11A is isolated from the supply port 12 by the vane 22A. At this timing, the rotor side communication path 23 </ b> A moves to a position where it does not communicate with the end plate side communication path 32.
On the other hand, in FIG. 1, the expansion chamber 11 </ b> B next to the expansion chamber 11 </ b> A is in communication with the supply port 12. Further, at this timing, the rotor side communication path 23 </ b> B has moved to a position where it is communicated with the end plate side communication path 32. In this state, the supply gap dimension is not sufficiently spaced from the supply port 12, so that the gas cannot be sufficiently introduced from the supply port 12, but the rotor side communication path 23B opens into the expansion chamber 11B. Thus, gas is supplied from the end plate side communication passage 32.
FIG. 2 shows a state during the supply stroke of the expansion chamber 11B. Gas is supplied to the expansion chamber 11B from the supply port 12, and also from the rotor side communication path 23B communicating with the end plate side communication path 32.
FIG. 3 shows a state immediately before the end of the supply stroke in the expansion chamber 11B. In this state, the opening area of the supply port 12 with respect to the expansion chamber 11B is narrowed by the vane 22B, and the supply gap dimension between the supply port 12 and the expansion chamber 11B does not have a sufficient interval. However, since the rotor side communication path 23B is in communication with the end plate side communication path 32, gas is supplied from the rotor side communication path 23B to the expansion chamber 11B.
In FIG. 4, the supply completion state of the expansion chamber 11B is shown. The rear end side of the expansion chamber 11B is isolated from the supply port 12 by the vane 22B. At this timing, the rotor side communication path 23B is also moved to a position where it does not communicate with the end plate side communication path 32.

As described above, each expansion chamber 11 is supplied with gas from the rotor side communication passage 23 in addition to the supply port 12 in the supply stroke, and therefore, the supply gap dimension between the supply port 12 and the expansion chamber 11 is small. Sufficient gas is supplied even at a timing that does not have a sufficient interval. In particular, the gas may be supplied from the rotor side communication passage 23 at a predetermined time from the start of the supply stroke and at least one predetermined time of the predetermined time before the end of the supply stroke.
Further, the arcuate portion 10B concentric with the rotor 20 can be formed on the opposing surface on the minor axis side of the elliptical shape, and the clearance between the stator 10 and the rotor 20 can be reduced. That is, since there is a clearance between the rotor 20 and the shaft 40, the rotor 20 is centered on the center of the space inside the stator 10, and the rotor 20 is not affected by the inclination of the shaft 40. This is because the 20 outer peripheral surface does not contact the inner peripheral surface of the space 10A. Therefore, even if the clearance between the stator 10 and the rotor 20 is reduced, the sliding friction of the rotor 20 with respect to the stator 10 can be reduced, and the rotor 20 can be easily started. Moreover, if the pressure balance of the both end surfaces of the rotor 20 is taken, the clearances at both end surfaces become equal, and leakage through the end surfaces of the rotor 20 can be minimized.

Next, assembly of the compressor according to the present embodiment will be described with reference to FIG.
First, the compression mechanism 41 including the fixed scroll component 41 a and the orbiting scroll component 41 b is assembled together with the shaft 40 and the rotation restraint mechanism 47. Thereafter, the rotor 43b is shrinked on the shaft 40. On the other hand, a stator 43 a is fixed to the body portion of the sealed container 42. The already assembled compression mechanism 41 is inserted into the sealed container 42 to which the stator 43a is fixed, and the bearing member 49 is welded and fixed to the sealed container 42. Next, the end plate 30 having the auxiliary bearing 30a is incorporated into the sealed container 42, and the position of the auxiliary bearing 30a is moved minutely while rotating the shaft 40. The bearing 30a is fixed. Thereafter, the upper shell 42a and the body portion 42b are welded, and current is supplied from the glass terminal 60, thereby magnetizing the rotor 43b. Thereafter, the expansion mechanism portion 1 is sequentially assembled, and finally an oil pump is attached to the lower end of the shaft 40, and the lower shell 42c is welded to the body portion 42b to complete.
Here, since there is a clearance between the rotor 20 and the shaft 40 by spline coupling, the compression mechanism 41 and the expansion mechanism 1 can be easily connected.
In the above-described embodiment, the vane groove 21 and the rotor side communication path 23 are described as being radially provided with respect to the center of the rotor 20. However, a predetermined inclination angle may be provided.
The expansion mechanism portion according to the present embodiment constitutes a refrigeration cycle together with a compressor, a radiator, and a condenser, supplies high-pressure refrigerant gas radiated by the radiator from the supply port 12, and is discharged from the discharge port 31. By guiding the gas to the condenser, the rotor 20 rotates and power can be output from the rotating shaft 40.

  The expansion mechanism part of the present embodiment is particularly useful as a compressor constituting a refrigeration cycle using carbon dioxide as a refrigerant.

The top view which shows the supply completion state of one expansion chamber in the compressor of one Example of this invention Plan view showing that the next expansion chamber in the compressor is in the supply stroke The top view which shows the state just before the end of the supply stroke of the expansion chamber in the compressor The top view which shows the supply completion state of the expansion chamber in the compressor Side sectional view of the expansion mechanism in the compressor Side sectional view of a compressor using the same expansion mechanism

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Expansion mechanism part 10 Stator 11 Expansion space 20 Rotor 21 Vane groove 22 Vane 23 Rotor side communication path 30 End plate 31 Discharge port 32 End plate side communication path 41 Compression mechanism part

Claims (5)

A compressor having an expansion mechanism and a compression mechanism;
The expansion mechanism section slides in a vane groove included in the rotor, a stator that forms a space therein, a cylindrical rotor that rotates in the space inside the stator, a shaft that rotationally drives the rotor, and the rotor. A vane, an end plate that seals the end surface of the rotor and the end surface of the stator, a supply port that supplies gas to an expansion space formed between the stator and the rotor, and the gas from the expansion space. A compressor having a discharge port for discharging, wherein the rotor and the shaft are spline-coupled, and the shaft is used as a drive shaft of the compression mechanism section.   The compressor according to claim 1, wherein the rotor is provided so as to be movable in the axial direction with respect to the shaft.   The space formed inside the stator has an elliptical shape in a plan view, and an arc portion concentric with the rotor is formed on an opposing surface of the elliptical minor axis side. The compressor according to 1.   The compressor according to claim 3, wherein the plurality of vanes are arranged such that at least one of the vanes is arranged in the arc portion during operation of the rotor. 2. The compressor according to claim 1, wherein a plurality of sets of the supply port and the discharge port are provided, the supply ports are arranged symmetrically with respect to the axis, and the discharge ports are arranged symmetrically with respect to the axis. .

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