JP2003254272A - Rotary compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary compressor of a so-called internal intermediate pressure type multistage compression type having a structure wherein back pressure is applied to a vane of a second rotary compression element without trouble. <P>SOLUTION: The rotary compressor comprises, in a hermetic container, an electric element, and a first and the second rotary compression element 32 and 34 driven by the electric element. A roller is fitted between a cylinder 38 constituting the second rotary compression element 34 and an eccentric portion formed on a rotary shaft 16 of the electric element so as to rotate eccentrically in the cylinder 38, an upper support member 54 is disposed to close an open face of the cylinder 38, the vane is brought in contact with the roller to divide the cylinder 38 into a low pressure chamber and a high pressure chamber, and a back pressure chamber is defined to apply back pressure to the vane. The upper support member 54 has a back pressure passage 72 interconnecting the high pressure chamber in the cylinder 38 and the back pressure chamber. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises first and second rotary compression elements driven by electric elements in a closed container, compressed by the first rotary compression element and discharged into the closed container. The present invention also relates to a rotary compressor that compresses intermediate pressure gas with a second rotary compression element.

[0002]

2. Description of the Related Art Conventionally, a rotary compressor of this type has, as disclosed in, for example, Japanese Patent Application Laid-Open No. 2-294587, a first and a second rotary compression element at the lower part of a hermetic container.
An electric element is provided on the upper part of the cylinder, a support member that closes the opening surface below the cylinder, a roller that rotates along the inner wall of the cylinder by an eccentric portion integrally formed with the rotation shaft of the electric element, and this roller. A first rotary compression element composed of a vane whose tip portion abuts and reciprocally slides in a groove provided in the cylinder; a support member for closing the opening surface above the cylinder and the cylinder; and an electric element. An eccentric part formed integrally with the rotary shaft and provided on the first rotary compression element;
A roller that rotates along the inner wall of the cylinder by an eccentric portion that is opposed to 0 °, and a vane that reciprocally slides in a groove that is provided in the cylinder when its tip end contacts the roller It is composed of two rotary compression elements.

Gas (refrigerant gas) is sucked into the low pressure chamber side of the cylinder from the suction port of the first rotary compression element, and is compressed by the operation of the rollers and vanes to become an intermediate pressure, which is the discharge port from the high pressure chamber side of the cylinder. , And is discharged into the closed container through the discharge muffling chamber. The intermediate pressure gas discharged into the closed container is sucked into the low pressure chamber side of the cylinder from the suction port of the second rotary compression element, and the second stage compression is performed by the operation of the roller and the vane, and the high temperature and high pressure gas is discharged. And is discharged from the high pressure chamber side through the discharge port and the discharge muffling chamber.

The gas discharged from the rotary compressor flows into the radiator of the refrigerant circuit, and after radiating the heat, it is throttled by the expansion valve and absorbed by the evaporator, and is sucked into the first rotary compression element of the rotary compressor. repeat.

The high-pressure refrigerant discharged into the compression chamber of the second rotary compression element is provided on the back surface of the vane through an introduction path provided from the compression chamber of the second rotary compression element to the back surface of the vane. The back pressure chamber of the vane is filled with the second-stage discharge pressure. As a result, the vanes provided on the second rotary compression element act as a force to push the vanes later. That is, the conventional rotary compressor is
The discharge pressure to the second rotary compression element is used as the back pressure of the vane to press the vane against the roller, and even if the pressure in the compression chamber of the second rotary compression element becomes high, the vane can resist the force. Was configured to obtain the back pressure of.

[0006]

A vane attached to such a rotary compressor is inserted into a guide groove provided in the radial direction of the cylinder so as to be movable in the radial direction of the cylinder. Since this vane needs to be pressed against the roller side, conventionally, a structure has been adopted in which the vane is pressed against the roller by the biasing force of the spring and the back pressure from the back pressure chamber. In the rotary compression element of No. 2, since the pressure in the cylinder becomes higher than the intermediate pressure in the closed container, the pressure in the closed container cannot be used as the back pressure of the vane, and the vane is urged to the roller side. Will cause problems.

The present invention was made in order to solve the problems of the prior art, and is a so-called internal intermediate pressure type multi-stage compression type structure in which back pressure can be applied to the vanes of the second rotary compression element without hindrance. It aims at providing the rotary compressor of.

[0008]

That is, in the rotary compressor of the present invention, an electric element and first and second rotary compression elements driven by the electric element are provided in a closed container.
The second rotary compression element is constituted by discharging the gas compressed by the first rotary compression element into the closed container and further compressing the discharged intermediate-pressure gas by the second rotary compression element. For engaging with an eccentric portion formed on the rotating shaft of the cylinder and the electric element for rotating eccentrically in the cylinder, a closing member for closing the opening surface of the cylinder, and a low pressure chamber for contacting the roller with the inside of the cylinder. Side and a high pressure chamber side, a back pressure chamber for applying a back pressure to the vane, and a back pressure passage formed in the closing member to connect the high pressure chamber side and the back pressure chamber in the cylinder. Therefore, the pressure on the high pressure chamber side in the cylinder can be supplied to the back pressure chamber via the back pressure passage. Further, since the discharge pressure or less is used as the back pressure of the vane, the reliability of the vane nose portion is improved and the power required for moving the vane to the top dead center can be reduced.

As a result, in the rotary compressor having an intermediate pressure in the closed container, back pressure for urging the vane toward the roller can be applied without any trouble.
Particularly, since the back pressure passage is formed in the closing member, the back pressure passage can be easily processed, and the production cost can be reduced by simplifying the structure of the cylinder.

In the rotary compressor according to the second aspect of the present invention, in addition to the above, the opening on the high pressure chamber side of the back pressure passage is opened and closed by the roller depending on the rotational position of the roller.
For example, as described in claim 3, the rotation position of the roller is 90 ° or more 3
By opening the opening of the back pressure passage within the range of 00 ° or less, the gas with the initial suction pressure that was sucked into the cylinder enters the back pressure chamber and re-expands, reducing the compression efficiency, and The gas that became high pressure in the stage enters the back pressure chamber,
It is possible to effectively eliminate the inconvenience that the vane biasing force becomes excessive and the input is increased, or the durability of the vane and the roller is reduced.

As a result, according to the present invention, it is possible to improve the operating efficiency, durability, input reduction, etc. while simplifying the structure of the rotary compressor.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows, as an embodiment of the rotary compressor of the present invention, first and second rotary compression elements 32, 3
4 is a longitudinal sectional view of an internal intermediate pressure type multi-stage (two-stage) compression type rotary compressor 10, FIG. 2 is a front view of the rotary compressor 10, FIG. 3 is a side view of the rotary compressor 10, and FIG. One longitudinal sectional view, FIG. 5 is another longitudinal sectional view of the rotary compressor 10, FIG. 6 is a plan sectional view of the electric element 14 portion of the rotary compressor 10, and FIG. 7 is a rotary compression mechanism portion 18 of the rotary compressor 10. Each of the enlarged cross-sectional views is shown.

In each figure, 10 is carbon dioxide (CO
This is an internal intermediate pressure type multi-stage compression type rotary compressor using 2) as a refrigerant.
Is a cylindrical closed container 12 made of a steel plate, an electric element 14 arranged and housed above the internal space of the closed container 12 and a lower side of the electric element 14, and driven by a rotary shaft 16 of the electric element 14. First rotary compression element 32
The rotary compression mechanism portion 18 includes the (first stage) and the second rotary compression element 34 (second stage).

The height of the rotary compressor 10 of the embodiment is 220 mm (outer diameter 120 mm), and the electric element 1
4 has a height of about 80 mm (outer diameter 110 mm), and the rotary compression mechanism 18 has a height of about 70 mm (outer diameter 110 m).
m), the distance between the electric element 14 and the rotary compression mechanism portion 18 is about 5 mm. In addition, the second rotary compression element 34
The excluded volume of is set smaller than the excluded volume of the first rotary compression element 32.

The closed container 12 has a thickness of 4.5 mm in the embodiment.
It is composed of the steel plate of
4A and the container main body 12A that houses the rotary compression mechanism portion 18,
It is composed of a substantially bowl-shaped end cap (lid) 12B that closes the upper opening of the container body 12A, and a circular mounting hole 12D is formed in the center of the upper surface of the end cap 12B.
Is formed, and the electric element 14 is provided in the mounting hole 12D.
Terminal for supplying power to the unit (wiring omitted) 20
Is attached.

In this case, the end cap 12B around the terminal 20 is formed with a stepped portion 12C having a predetermined curvature in an annular shape by press forming. Also, terminal 20
Is a circular glass portion 20A to which the electrical terminal 139 is attached and is attached, and a metal attachment portion 20 formed around the glass portion 20A and projecting obliquely outward and downward in a brim shape.
It is composed of B and.

The thickness of the mounting portion 20B is 2.4 ± 0.5.
It is set to mm. Then, in the terminal 20, the glass portion 20A is inserted from the lower side into the mounting hole 12D so as to face the upper side, and the mounting portion 20B is brought into contact with the peripheral edge of the mounting hole 12D, and the peripheral edge of the mounting hole 12D of the end cap 12B. It is fixed to the end cap 12B by welding the mounting portion 20B to.

The electric element 14 is a stator 22 mounted in an annular shape along the inner peripheral surface of the upper space of the closed container 12.
And a rotor 24 inserted and arranged inside the stator 22 with a slight gap. The rotor 24 is fixed to the rotating shaft 16 that extends vertically through the center.

The stator 22 includes a laminated body 26 in which donut-shaped electromagnetic steel sheets are laminated, and a stator coil 2 wound around the teeth of the laminated body 26 by a direct winding (concentrated winding) method.
8 (FIG. 6). Like the stator 22, the rotor 24 is also formed of a laminated body 30 of electromagnetic steel plates, and a permanent magnet MG is inserted into the laminated body 30.

An intermediate partition plate 36 is sandwiched between the first rotary compression element 32 and the second rotary compression element 34. That is, the first rotary compression element 32 and the second rotary compression element 34 include an intermediate partition plate 36, cylinders 38 and cylinders 40 arranged above and below the intermediate partition plate 36, and inside the upper and lower cylinders 38 and 40. And the upper and lower rollers 46 and 48 which are fitted to the upper and lower eccentric portions 42 and 44 provided on the rotary shaft 16 with a phase difference of 180 degrees and rotate eccentrically.
Upper and lower vanes 5 to be described later, which abut against the upper and lower cylinders 38 and 40 to divide them into the low pressure chamber side and the high pressure chamber side, respectively.
0 (the lower vane is not shown) and an upper support member as a closing member that closes the upper opening surface of the upper cylinder 38 and the lower opening surface of the lower cylinder 40 and also serves as a bearing for the rotary shaft 16. 54 and a lower support member 56.

Upper support member 54 and lower support member 56
The suction ports 161 and 162 at the upper and lower cylinders 3.
Suction passages 58, 60 communicating with the insides of 8, 40, respectively.
Then, the recessed discharge silencing chambers 62 and 64 are formed, and the openings of the discharge silencing chambers 62 and 64 are closed by covers. That is, the discharge muffling chamber 62 is closed by the upper cover 66 as a cover, and the discharge muffling chamber 64 is closed by the lower cover 68 as a cover.

In this case, a bearing 54A is formed upright in the center of the upper support member 54, and a cylindrical bush 122 is attached to the inner surface of the bearing 54A. Also,
A bearing 56A is formed through the center of the lower support member 56, and the cylindrical bush 1 is also formed on the inner surface of the bearing 56A.
23 is attached. These bushes 122, 123
Is made of a material with good slidability as described below,
The rotary shaft 16 is held by the bearing 54A of the upper support member 54 and the bearing 56A of the lower support member 56 via the bushes 122 and 123.

In this case, the lower cover 68 is made of a donut-shaped circular steel plate, and is fixed to the lower support member 56 from the bottom at four locations in the peripheral portion by the main bolts 129 ... The lower surface opening of the discharge muffling chamber 64 that communicates with the inside of the lower cylinder 40 of the first rotary compression element 32 is closed. The tips of the main bolts 129 ... Are screwed into the upper support member 54. The inner peripheral edge of the lower cover 68 projects inward from the inner surface of the bearing 56A of the lower support member 56, whereby the lower end surface of the bush 123 is held by the lower cover 68 and prevented from falling off (FIG. 9). FIG. 10 shows the lower surface of the lower support member 56, and 128 is the discharge port 41 in the discharge muffling chamber 64.
Is a discharge valve of the first rotary compression element 32 that opens and closes.

The lower support member 56 is made of an iron-based sintered material (or a casting), and the surface (lower surface) on which the lower cover 68 is attached has a flatness of 0.
After being processed to 1 mm or less, steam treatment is added. By this steam treatment, the surface on the side to which the lower cover 68 is attached becomes iron oxide, so that the holes inside the sintered material are closed and the sealing performance is improved. This eliminates the need to provide a gasket between the lower cover 68 and the lower support member 56.

The discharge muffler chamber 64 and the electric element 14 side of the upper cover 66 in the closed container 12 are communicated with each other by a communication passage 63 which is a hole penetrating the upper and lower cylinders 38, 40 and the intermediate partition plate 36. (Fig. 4). In this case, the communication passage 6
An intermediate discharge pipe 121 is erected at the upper end of the stator 3. The intermediate discharge pipe 121 is a stator 22 of the upper electric element 14.
It is directed to the gap between the adjacent stator coils 28, which are wound on each other (FIG. 6).

Further, the upper cover 66 closes the upper opening of the discharge muffling chamber 62 which communicates with the inside of the upper cylinder 38 of the second rotary compression element 34 at the discharge port 39, and the closed container 1
The inside of 2 is partitioned into the discharge silencing chamber 62 and the electric element 14 side. This upper cover 66 has a thickness of 2 mm or more 1 as shown in FIG.
The upper support member 54 has a diameter of 0 mm or less (most preferably 6 mm in the embodiment) and is formed of a substantially donut-shaped circular steel plate having a hole through which the bearing 54A of the upper support member 54 passes. With the beaded gasket 124 (FIG. 12) sandwiched between the main gasket 7 and the main bolt 7 having four peripheral parts through the gasket 124.
It is fixed to the upper support member 54 from above by 8 ... The tips of the main bolts 78 ...
Screw to 6.

By making the upper cover 66 have such a thickness dimension, it is possible to achieve miniaturization while sufficiently withstanding the pressure of the discharge muffling chamber 62, which is higher than the pressure in the closed container 12, and to achieve the size reduction, and thus the electric element 1
It is also possible to secure an insulation distance from 4. Further, an O-ring 126 is provided between the inner peripheral edge of the upper cover 66 and the outer surface of the bearing 54A (FIG. 12). By sealing the bearing 54A side by the O-ring 126, it is possible to sufficiently seal the inner peripheral edge of the upper cover 66 and prevent gas leakage, and it is possible to expand the volume of the discharge muffling chamber 62 and It is not necessary to fix the inner peripheral edge side of the upper cover 66 to the bearing 54A by the ring.

Here, in FIG. 11, reference numeral 127 is a discharge valve of the second rotary compression element 34 which opens and closes the discharge port 39 in the discharge muffling chamber 62.

Next, the intermediate partition plate 3 for closing the lower opening surface of the upper cylinder 38 and the upper opening surface of the lower cylinder 40.
In FIG. 6, a position corresponding to the suction side in the upper cylinder 38 extends from the outer peripheral surface to the inner peripheral surface as shown in FIGS. 13 and 14, and the outer peripheral surface and the inner peripheral surface communicate with each other to form an oil supply passage. The through hole 131 is formed, and the sealing material 132 on the outer peripheral surface side of the through hole 131 is press-fitted to seal the outer peripheral surface side opening. A communication hole 133 extending upward is formed in the middle of the through hole 131.

On the other hand, the suction port 161 of the upper cylinder 38
A communication hole 134 communicating with the communication hole 133 of the intermediate partition plate 36 is formed on the (suction side) (FIG. 15). Further, as shown in FIG. 7, an oil hole 80 is provided in the rotary shaft 16 in the vertical direction with respect to the shaft center, and horizontal oil supply holes 82, 84 communicating with the oil hole 80 (the vertical eccentric portions 42, 44 of the rotary shaft 16). Is also formed), the opening on the inner peripheral surface side of the through hole 131 of the intermediate partition plate 36 is
It communicates with the oil hole 80 via 2, 84.

As will be described later, since the inside pressure of the closed container 12 becomes an intermediate pressure, it becomes difficult to supply oil into the upper cylinder 38 which becomes a high pressure in the second stage. , Pumped up from the oil sump at the bottom of the closed container 12 to raise the oil hole 80,
The oil discharged from 84 is the through hole 131 of the intermediate partition plate 36.
Then, the gas is supplied from the communication holes 133 and 134 to the suction side (suction port 161) of the upper cylinder 38.

In FIG. 16, L shows the pressure fluctuation on the suction side of the upper cylinder 38, and P1 shows the pressure on the inner peripheral surface of the intermediate partition plate 36. As indicated by L1 in this figure, the pressure on the suction side of the upper cylinder 38 (suction pressure) becomes lower than the pressure on the inner peripheral surface side of the intermediate partition plate 36 due to suction pressure loss during the suction process. During this period, oil is supplied from the through hole 131 and the communication hole 133 of the intermediate partition plate 36 into the upper cylinder 38 through the communication hole 134 of the upper cylinder 38.

As described above, the upper and lower cylinders 38 and 40, the intermediate partition plate 36, the upper and lower support members 54 and 56, and the upper and lower covers 6
6 and 68 are respectively fastened from above and below by four main bolts 78 ... And main bolts 129 ..., but further, upper and lower cylinders 38, 40, intermediate partition plate 36, and upper and lower support members 5
4, 56 are fastened by auxiliary bolts 136, 136 located outside these main bolts 78, 129 (FIG. 4). The auxiliary bolt 136 is inserted from the upper support member 54 side, and the tip end is screwed into the lower support member 56.

The auxiliary bolt 136 is located near a guide groove 70, which will be described later, of the vane 50 described above.
By thus adding the auxiliary bolts 136 and 136 to integrate the rotary compression mechanism portion 18, the sealing performance against the extremely high pressure inside is ensured and the vicinity of the guide groove 70 of the vane 50 is ensured. Since it is tightened, it is possible to prevent the inconvenience that the high pressure back pressure applied to the vane 50 leaks from the back pressure chamber 74 described later.

On the other hand, a guide groove 70 for accommodating the vane 50 and an accommodating portion 70A for accommodating a spring 76 as a spring member are formed outside the guide groove 70 in the upper cylinder 38. The storage section 70A is open to the guide groove 70 side and the closed container 12 (container body 12A) side (FIG. 8). The spring 76 contacts the outer end of the vane 50 and constantly urges the vane 50 toward the roller 46. Further, a metal plug 137 is provided in the housing portion 70A of the spring 76 on the side of the closed container 12 and serves to prevent the spring 76 from coming off.

In this case, the outer size of the plug 137 is the storage portion 7.
The plug 137 is set to be smaller than the inner dimension of 0A, and is inserted into the accommodating portion 70A by a clearance fit. Further, an O-ring 138 for sealing between the plug 137 and the inner surface of the housing portion 70A is attached to the peripheral surface of the plug 137. The outer end of the upper cylinder 38, that is, the distance between the outer end of the storage portion 70A and the container body 12A of the closed container 12 is smaller than the distance from the O-ring 138 to the end of the plug 137 on the closed container 12 side. It is set. Due to this dimensional relationship, the plug 137 is accommodated in the storage portion 70A.
As in the case where the upper cylinder 38 is deformed by press-fitting the inside, the sealability between the upper cylinder 38 and the upper support member 54 is deteriorated, and it is possible to avoid the inconvenience that the performance is deteriorated.

The outer size of the plug 137 is set smaller than the inner size of the storage section 70A so that the plug 137 can be stored in the storage section 70A.
Even when the clearance is fitted in A, the distance between the upper cylinder 38 and the closed container 12 is set smaller than the distance from the O-ring 138 to the end of the plug 137 on the closed container 12 side. High pressure (back pressure of vane 50)
Even if the plug 137 is moved in the direction of being pushed out of the storage section 70A by the plug 137, the O-ring 138 is still positioned in the storage section 70A and seals when the plug 137 comes into contact with the closed container 12 and is prevented from moving. There is no problem with the function of.

On the other hand, on the opposite side of the guide groove 70 in the upper cylinder 38 from the roller 46, the aforementioned back pressure chamber 74 for applying a back pressure for urging the vane 50 to the roller 46 is provided. Has been formed. The back pressure chamber 74 has a substantially cylindrical shape extending between the intermediate partition plate 36 and the upper support member 54, and is formed so as to penetrate into the upper cylinder 38 (FIG. 19). The back pressure chamber 74 communicates with the storage portion 70A and the guide groove 70, and is connected from a back pressure passage 72 described later to the upper cylinder 38
The gas on the high pressure chamber side inside flows into the back pressure chamber 74 to guide the guide groove 7
Back pressure is applied from behind the vane 50 in 0 to urge the vane 50 toward the roller 46 side.

The back pressure passage 72 is formed in the upper support member 54 (closing member). This back pressure passage 7
One end of 2 is opened in the upper cylinder 38 by an opening 72A formed in the lower surface of the upper support member 54 at a position corresponding to the high pressure chamber side in the upper cylinder 38, and the other end is in a position corresponding to the back pressure chamber 74. The lower surface of the upper support member 54 is opened (see FIG.
), The high pressure chamber side in the upper cylinder 38 communicates with the back pressure chamber 74. The pressure on the high pressure chamber side in the cylinder 38 is supplied to the back pressure chamber 74 via the back pressure passage 72. When the rotation position of the roller 46 when the vane 50 is most protruded is 180 °, the opening of the back pressure passage 72 on the high pressure chamber side is within a predetermined range before and after the rotation position (180 °) of the roller 46. In the rotational position, the roller 46 opens the opening 72A of the back pressure passage 72.

In this case, in the embodiment, the back pressure is within the range of 90 ° or more and 300 ° or less, which is a predetermined range before and after the rotational position of the roller 46 is 180 ° (position (C) in FIG. 19). The opening 72A of the passage 72 is arranged so that the opening 72A is opened. That is, the roller 72 rotates and the opening 72A is opened at a position where the rotation position becomes 90 ° ((F) in FIG. 19) and closed at a position where it becomes 300 ° ((B) in FIG. 19). . Therefore, this 90
The pressure on the high pressure chamber side in the upper cylinder 38 is supplied to the back pressure chamber 74 via the back pressure passage 72 at the rotational position of not less than 300 ° and not less than 300 °.

As a result, the refrigerant gas on the high pressure chamber side in the upper cylinder 38 is caused to flow into the back pressure chamber 74 and a back pressure is applied to the vane 50, so that the vane 50 can be biased toward the roller 46 side. Become.

By the way, the connecting portion 90 which connects the upper and lower eccentric portions 42 and 44 formed integrally with the rotating shaft 16 with a phase difference of 180 degrees has a sectional shape of the rotating shaft 16.
The non-circular shape, for example, a rugby ball shape, has a larger cross-sectional area than the circular cross-section and has rigidity (FIG. 17). That is, the vertical eccentric parts 42, 4 provided on the rotary shaft 16
The cross-sectional shape of the connecting portion 90 connecting the four is the vertical eccentric portion 42
The wall thickness is increased in the direction orthogonal to the eccentric direction of 44 (hatched portion in the figure).

As a result, the cross-sectional area of the connecting portion 90 that connects the vertical eccentric portions 42 and 44 integrally provided on the rotary shaft 16 is increased, and the second moment of area is increased to increase the strength (rigidity) and durability. It improves the reliability and reliability. Especially when two-stage compression of a refrigerant having a high working pressure is performed, the load applied to the rotating shaft 16 increases due to a large pressure difference between high pressure and low pressure, but the cross-sectional area of the connecting portion 90 is increased to increase its strength (rigidity).
Therefore, the rotation shaft 16 is prevented from being elastically deformed.

In this case, the center of the upper eccentric portion 42 is O1.
And the center of the lower eccentric portion 44 is O2, the center of the arc of the surface of the coupling portion 90 on the eccentric direction side of the eccentric portion 42 is O.
1, the center of the arc of the surface of the connecting portion 90 on the eccentric direction side of the eccentric portion 44 is O2. As a result, the rotary shaft 16 is chucked by the cutting machine and the vertical eccentric parts 42 and 44 and the connecting part 9 are attached.
When cutting 0, after processing the eccentric portion 42, only the radius is changed to process one surface of the connecting portion 90, the chuck position is changed to process the other surface of the connecting portion 90, and only the radius is changed. Then, the work of machining the eccentric portion 44 becomes possible. As a result, the number of times of re-chucking the rotary shaft 16 is reduced, and the productivity is remarkably improved.

In this case, carbon dioxide (CO2) as an example of carbon dioxide which is a natural refrigerant is used as the refrigerant in consideration of flammability and toxicity, and the oil as the lubricating oil is Existing oils such as mineral oil, alkylbenzene oil, ether oil and ester oil are used.

The suction passage 5 of the upper support member 54 and the lower support member 56 is provided on the side surface of the container body 12A of the closed container 12.
The sleeves 141, 142, 143, and 144 are welded and fixed to the positions corresponding to the upper side of the discharge silencer chamber 62 and the upper cover 66 (the position substantially corresponding to the lower end of the electric element 14). The sleeves 141 and 142 are vertically adjacent to each other, and the sleeve 143 is
1 is on a substantially diagonal line. Further, the sleeve 144 is located at a position displaced from the sleeve 141 by approximately 90 degrees.

Then, one end of a refrigerant introducing pipe 92 for introducing a refrigerant gas into the upper cylinder 38 is inserted and connected in the sleeve 141, and one end of the refrigerant introducing pipe 92 is communicated with the suction passage 58 of the upper cylinder 38. It This refrigerant introduction pipe 9
2 passes through the upper side of the closed container 12 to reach the sleeve 144, and the other end is inserted and connected in the sleeve 144 to communicate with the closed container 12.

In the sleeve 142, the lower cylinder 4
One end of a refrigerant introduction pipe 94 for introducing the refrigerant gas to 0 is inserted and connected, and one end of this refrigerant introduction pipe 94 is communicated with the suction passage 60 of the lower cylinder 40. This refrigerant introducing pipe 94
The other end of is connected to the lower end of the accumulator 146. Further, a refrigerant discharge pipe 96 is inserted and connected in the sleeve 143, and one end of the refrigerant discharge pipe 96 has a discharge muffling chamber 62.
Be communicated to.

The accumulator 146 is a tank for separating the suction refrigerant into gas and liquid, and is attached to a bracket 147 on the closed container side welded and fixed to the upper side surface of the container body 12A of the closed container 12 via a bracket 148 on the accumulator side. Has been. The bracket 148 extends upwardly from the bracket 147, and the accumulator 146
Is held in a substantially central portion in the vertical direction, and in this state, the accumulator 146 is arranged along the side of the closed container 12.

The refrigerant introducing pipe 92, after coming out of the sleeve 141, bends to the right in the embodiment and then rises, and the lower end of the accumulator 146 comes close to the refrigerant introducing pipe 92. Therefore, the refrigerant introduction pipe 94 that descends from the lower end of the accumulator 146 is routed so as to bypass the left side of the sleeve 141 opposite to the bending direction of the refrigerant introduction pipe 92 and reach the sleeve 142 (FIG. 3). ).

That is, the upper support member 54 and the lower support member 5
The refrigerant introduction pipes 92, 94 communicating with the suction passages 58, 60 of No. 6 are bent in the opposite directions in the horizontal direction when viewed from the closed container 12, whereby the vertical dimension of the accumulator 146 is enlarged. Therefore, even if the volume is increased, consideration is given so that the refrigerant introduction pipes 92 and 94 do not interfere with each other.

Further, a flange portion 15 is formed around the outer surfaces of the sleeves 141, 143, 144 so that a coupler for pipe connection can be engaged.
1 is formed, and a thread groove 152 for pipe connection is formed on the inner surface of the sleeve 142. As a result, the sleeves 141, 143, 144 can be easily connected to the flange 151 while the coupler of the test pipe is easily connected to the sleeve 142 when the airtightness test is performed in the completion inspection in the manufacturing process of the rotary compressor 10. Screw groove 15
2 can be used to easily screw the test pipe. In particular, the sleeves 141 and 142 that are vertically adjacent to each other
Since the flange 151 is formed on one sleeve 141 and the thread groove 152 is formed on the other sleeve 142, the test pipe can be connected to each sleeve 141, 142 in a narrow space.

The rotary compressor 1 of the embodiment
0 is used in the refrigerant circuit of the water heater 153 as shown in FIG. That is, the refrigerant discharge pipe 96 of the rotary compressor 10 is connected to the inlet of the gas cooler 154 for heating water. The gas cooler 154 is provided in a hot water storage tank (not shown) of the hot water supply device 153. The pipe exiting the gas cooler 154 is passed through an expansion valve 156 as a pressure reducing device and then an evaporator 157.
And the outlet of the evaporator 157 is connected to the refrigerant introduction pipe 94. Further, although not shown in FIGS. 2 and 3, a defrost pipe 158 constituting a defrosting circuit branches from the middle portion of the refrigerant introduction pipe 92, and the defrost pipe 158 of the gas cooler 154 is connected via an electromagnetic valve 159 as a flow path control device. It is connected to the refrigerant discharge pipe 96 leading to the inlet. The accumulator 146 is omitted in FIG.

The operation of the above configuration will be described below. In the heating operation, the solenoid valve 159 is closed. Electric element 1 via terminal 20 and wiring not shown
When the stator coil 28 of No. 4 is energized, the electric element 14
Starts and the rotor 24 rotates. By this rotation, the upper and lower rollers 46 and 48 fitted in the upper and lower eccentric portions 42 and 44 integrally provided with the rotating shaft 16 eccentrically rotate in the upper and lower cylinders 38 and 40.

As a result, the low pressure (first-stage suction pressure LP: which is sucked into the low-pressure chamber side of the lower cylinder 40 from the suction port 162 via the refrigerant introduction pipe 94 and the suction passage 60 formed in the lower support member 56. The refrigerant gas (4 MPaG) is compressed by the operation of the roller 48 and the vane to an intermediate pressure (MP1: 8 MPaG) from the high pressure chamber side of the lower cylinder 40 to the discharge port 41 and the discharge muffling chamber 64 formed in the lower support member 56. Intermediate discharge pipe 121 via communication passage 63
Is discharged into the closed container 12.

At this time, since the intermediate discharge pipe 121 is directed toward the gap between the adjacent stator coils 28, 28 wound around the stator 22 of the upper electric element 14, the refrigerant gas having a relatively low temperature is still present. Can be positively supplied in the direction of the electric element 14, and the temperature rise of the electric element 14 can be suppressed. Moreover, by this, the closed container 1
The inside of 2 becomes an intermediate pressure (MP1).

The intermediate pressure refrigerant gas in the closed container 12 is discharged from the sleeve 144 (the intermediate discharge pressure is equal to the above-mentioned MP
1) The refrigerant is introduced into the low pressure chamber side of the upper cylinder 38 from the suction port 161 through the refrigerant introduction pipe 92 and the suction passage 58 formed in the upper support member 54 (second-stage suction pressure MP
2). The sucked intermediate-pressure refrigerant gas is compressed in the second stage by the operation of the roller 46 and the vane 50. However, the opening 72A of the back pressure passage 72 is in the range where the rotational position of the roller 46 is 90 ° or more and 300 ° or less. Is configured to open, and suitable back pressure can be applied to the vane 50.
0 can be operated smoothly. Then, the sucked intermediate-pressure refrigerant gas is compressed in the second stage by the operation of the roller 46 and the vane 50 to become a high-temperature high-pressure refrigerant gas (second-stage discharge pressure HP: 12 MPaG), and from the high-pressure chamber side. It flows into the gas cooler 154 through the discharge port 39, the discharge muffling chamber 62 formed in the upper support member 54, and the refrigerant discharge pipe 96. At this time, the refrigerant temperature is approximately +100.
The temperature rises to 0 ° C., and the high-temperature and high-pressure refrigerant gas radiates heat to heat the water in the hot water storage tank to generate hot water of about + 90 ° C.

In the above-described second stage compression in the upper cylinder 38, in the initial stage of sucking the refrigerant gas in which the rotational angular position of the roller 46 starts from 0 °, the suction pressure (MP1) is also applied to the high pressure chamber side in the upper cylinder 38. Is equivalent to Therefore, when this refrigerant gas flows into the back pressure chamber 74, the refrigerant gas is re-expanded and the compression efficiency is reduced. In addition, the vane 50 and the roller 46
It cannot be expected to function as back pressure that biases the side.

On the other hand, the rotation angle position of the roller 46 is 360
At the final stage of compression of the refrigerant gas heading toward °, the high-pressure chamber side has the extremely high high-pressure HP described above. Therefore, when the extremely high-pressure refrigerant gas flows into the back pressure chamber 74, the vane 50 is pressed against the roller 46 by the back pressure. The force becomes excessively large, the work amount for pushing the vane 50 into the guide groove 70 side becomes large, and the input (electric power) increases, so that the efficiency decreases.

However, in the present invention, as described above, the roller 46 opens the opening 72A of the back pressure passage 72 only when the rotational position of the roller 46 is 90 ° or more and 300 ° or less,
The high pressure chamber side and the back pressure chamber 74 are communicated with each other, and 0 ° to 90 °
Since the opening 72A is closed so as not to communicate with each other in the initial stage of inhalation in the range of ° and the final stage of compression in the range of 300 to 360 °, it is possible to prevent such efficiency deterioration. Also, vane 50
Since it is possible to prevent excessive back pressure that pushes the roller against the roller 46,
The durability of both is improved, and the lubrication characteristics are also good.

On the other hand, the refrigerant itself is cooled in the gas cooler 154 and exits the gas cooler 154. Then, after being decompressed by the expansion valve 156, it flows into the evaporator 157 and evaporates, and the accumulator 146 (not shown in FIG. 18).
After that, the cycle of being sucked into the first rotary compression element 32 from the refrigerant introduction pipe 94 is repeated.

Particularly, in a low outside temperature environment, such heating operation causes frost to grow on the evaporator 157. In that case, the solenoid valve 159 is opened, the expansion valve 156 is fully opened, and the evaporator 157 is defrosted. As a result, the medium-pressure refrigerant (including a small amount of high-pressure refrigerant discharged from the second rotary compression element 34) in the closed container 12 reaches the gas cooler 154 through the defrost pipe 158. The temperature of this refrigerant is about +50 to + 60 ° C., and the gas cooler 154 does not dissipate heat, but the refrigerant initially absorbs heat. The refrigerant discharged from the gas cooler 154 is the expansion valve 1
It passes through 56 and reaches the evaporator 157. That is,
The evaporator 157 is substantially directly supplied with the refrigerant having a substantially intermediate pressure and having a relatively high temperature without being decompressed, whereby the evaporator 157 is heated and defrosted.

Here, when the high-pressure refrigerant discharged from the second rotary compression element 34 is supplied to the evaporator 157 without depressurization and defrosted, the expansion valve 156 is fully opened and the first rotation is performed. The suction pressure of the compression element 32 rises, which causes the first
The discharge pressure (intermediate pressure) of the rotary compression element 32 is increased.
This refrigerant is discharged through the second rotary compression element 34, but because the expansion valve 156 is fully open, the second rotary compression element 3
Since the discharge pressure of No. 4 becomes the same as the suction pressure of the first rotary compression element 32, a pressure reversal phenomenon occurs between the discharge (high pressure) and suction (intermediate pressure) of the second rotary compression element 34. I will end up. However, since the refrigerant gas of the intermediate pressure discharged from the first rotary compression element 32 is taken out from the closed container 12 to defrost the evaporator 157 as described above, the reversal phenomenon of the high pressure and the intermediate pressure. Will be able to prevent.

As described above, since the back pressure passage 72 that connects the high pressure chamber side in the upper cylinder 38 and the back pressure chamber 74 is formed in the upper support member 54, the cylinder 38 is connected via the back pressure passage 72. The pressure on the high pressure chamber side can be supplied to the back pressure chamber 74. As a result, in the rotary compressor 10 in which the inside pressure of the closed container 12 is an intermediate pressure, it is possible to apply the back pressure for urging the vane 50 to the roller 46 side without any trouble. Particularly, the back pressure passage 7 is formed in the upper support member 54.
The back pressure passage 72
The back pressure passage 72 can be processed very easily.
The workability of can be greatly improved.

In the above embodiment, the back pressure passage 72 for communicating the high pressure chamber side in the upper cylinder 38 with the back pressure chamber 74.
Although the above is provided on the upper support member 54, the present invention is not limited to this, and the present invention is effective when the back pressure passage 72 is provided on the intermediate partition plate 36 (which serves as a closing member in the present invention).

Although carbon dioxide (CO2) is used as the refrigerant in the rotary compressor 10, the present invention is not limited to this refrigerant, and hydrocarbons (HC), ammonia (NH3), etc. may be used as other natural refrigerants. It is valid.

[0067]

As described above in detail, according to the present invention, the first rotary compression element is provided with the electric element and the first and second rotary compression elements driven by the electric element in the closed container. In the rotary compressor that discharges the gas compressed by the above into the closed container and further compresses the discharged intermediate pressure gas by the second rotary compression element, a cylinder and an electric motor for constituting the second rotary compression element. A roller that is fitted to an eccentric portion formed on the rotary shaft of the element and rotates eccentrically in the cylinder;
A closing member that closes the opening surface of the cylinder, a vane that abuts the roller and divides the inside of the cylinder into a low pressure chamber side and a high pressure chamber side, a back pressure chamber for applying a back pressure to the vane, and a closing member are formed. Since a back pressure passage that connects the high pressure chamber side in the cylinder and the back pressure chamber is provided, it is possible to supply the pressure on the high pressure chamber side in the cylinder to the back pressure chamber via the back pressure passage. become.

As a result, in the rotary compressor having an intermediate pressure in the closed container, back pressure for urging the vane toward the roller can be applied without any trouble.
Particularly, since the back pressure passage is formed in the closing member, the back pressure passage can be easily processed, and the production cost can be reduced by simplifying the structure of the cylinder.

In the rotary compressor according to the invention of claim 2, in addition to the above, the opening of the back pressure passage on the high pressure chamber side is opened and closed by the roller depending on the rotational position of the roller.
For example, as described in claim 3, the rotation position of the roller is 90 ° or more 3
By opening the opening of the back pressure passage within the range of 00 ° or less, the gas with the initial suction pressure that was sucked into the cylinder enters the back pressure chamber and re-expands, reducing the compression efficiency, and The gas that became high pressure in the stage enters the back pressure chamber,
It is possible to effectively eliminate the inconvenience that the vane biasing force becomes excessive and the input is increased, or the durability of the vane and the roller is reduced.

As a result, according to the present invention, it is possible to improve the operating efficiency, durability, input reduction, etc. while simplifying the structure of the rotary compressor.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a rotary compressor according to an embodiment of the present invention.

FIG. 2 is a front view of the rotary compressor of FIG.

3 is a side view of the rotary compressor of FIG. 1. FIG.

FIG. 4 is another vertical cross-sectional view of the rotary compressor of FIG.

FIG. 5 is another vertical cross-sectional view of the rotary compressor of FIG.

6 is a plan sectional view of an electric element portion of the rotary compressor of FIG. 1. FIG.

7 is an enlarged sectional view of a rotary compression mechanism portion of the rotary compressor of FIG.

8 is an enlarged sectional view of a vane portion of a second rotary compression element of the rotary compressor of FIG.

9 is a cross-sectional view of a lower support member and a lower cover of the rotary compressor of FIG.

10 is a bottom view of a lower support member of the rotary compressor of FIG. 1. FIG.

11 is a top view of an upper support member and an upper cover of the rotary compressor of FIG.

12 is a sectional view of an upper support member and an upper cover of the rotary compressor of FIG.

FIG. 13 is a top view of an intermediate partition plate of the rotary compressor of FIG.

FIG. 14 is a sectional view taken along the line AA of FIG.

15 is a top view of the upper cylinder of the rotary compressor of FIG. 1. FIG.

16 is a diagram showing pressure fluctuations on the suction side of the upper cylinder of the rotary compressor of FIG.

FIG. 17 is a cross-sectional view for explaining the shape of the connecting portion of the rotary shaft of the rotary compressor of FIG.

18 is a refrigerant circuit diagram of a hot water supply device to which the rotary compressor of FIG. 1 is applied.

19 is a diagram illustrating a back pressure passage of the upper cylinder of the rotary compressor of FIG.

20 is a side view of a rotary compression mechanism portion for showing a back pressure passage of the rotary compressor of FIG. 1. FIG.

[Explanation of symbols]

10 Rotary compressor 12 airtight container 14 Electric elements 16 rotation axes 18 Rotary compression mechanism 20 terminals 32 First rotary compression element 34 Second rotary compression element 36 Intermediate partition plate 38, 40 cylinders 39, 41 Discharge port 42 Eccentric part 44 Eccentric part 46 Laura 48 Roller 50 vanes 54 Upper support member 56 Lower support member 62 Discharge silencer 64 discharge silencer 66 Top cover 68 Lower cover 70 Guide groove 70A storage 72 Back pressure passage 72A opening 74 Back pressure chamber 76 spring 78,129 Main bolt 90 Connection 132 sealing material 137 plug 138 O-ring

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Takashi Sato             2-5-3 Keihan Hondori, Moriguchi City, Osaka Prefecture             Within Yo Denki Co., Ltd. (72) Inventor Dai Matsuura             2-5-3 Keihan Hondori, Moriguchi City, Osaka Prefecture             Within Yo Denki Co., Ltd. (72) Inventor Kazuya Sato             2-5-3 Keihan Hondori, Moriguchi City, Osaka Prefecture             Within Yo Denki Co., Ltd. (72) Inventor Hiroyuki Matsumori             2-5-3 Keihan Hondori, Moriguchi City, Osaka Prefecture             Within Yo Denki Co., Ltd. (72) Inventor Takayasu Saito             2-5-3 Keihan Hondori, Moriguchi City, Osaka Prefecture             Within Yo Denki Co., Ltd. (72) Inventor Haruhisa Yamazaki             2-5-3 Keihan Hondori, Moriguchi City, Osaka Prefecture             Within Yo Denki Co., Ltd. (72) Inventor Masaya Tadano             2-5-3 Keihan Hondori, Moriguchi City, Osaka Prefecture             Within Yo Denki Co., Ltd. (72) Inventor Satoru Imai             2-5-3 Keihan Hondori, Moriguchi City, Osaka Prefecture             Within Yo Denki Co., Ltd. (72) Inventor Atsushi Oda             2-5-3 Keihan Hondori, Moriguchi City, Osaka Prefecture             Within Yo Denki Co., Ltd. F-term (reference) 3H029 AA05 AA12 AB03 AB08 CC03                       CC25 CC87

Claims (3)

[Claims] 1. A hermetic container provided with an electric element and first and second rotary compression elements driven by the electric element, wherein the gas compressed by the first rotary compression element is contained in the hermetic container. Is discharged to the second, and the discharged intermediate pressure gas is discharged to the second
In the rotary compressor for compressing with the rotary compression element, a roller for eccentrically rotating in the cylinder, which is fitted to a cylinder for forming the second rotary compression element, and an eccentric portion formed on a rotation shaft of the electric element. A closing member that closes the opening surface of the cylinder; a vane that abuts the roller to divide the inside of the cylinder into a low pressure chamber side and a high pressure chamber side; and a back pressure chamber for applying a back pressure to the vane. A rotary compressor, comprising: a back pressure passage formed in the closing member and connecting the high pressure chamber side in the cylinder and the back pressure chamber. 2. The opening of the back pressure passage on the high pressure chamber side is
The rotary compressor according to claim 1, wherein the rotary compressor is opened and closed by the roller depending on a rotational position of the roller. 3. The rotation position of the roller is 90 ° or more 30
The rotary compressor according to claim 2, wherein the opening of the back pressure passage is opened in a range of 0 ° or less.