JP2003097433A - Hermetic electric compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hermetic electric compressor capable of preventing inconvenience resulting from deformation of an end cap of a hermetic vessel. SOLUTION: This compressor comprises an electric element 14 inside the hermetic vessel 12 and a rotary compression mechanism part 18 driven by the electric element 14. The rotary compression mechanism part 18 discharges a refrigerant into the hermetic vessel 12 by compression. The compressor also comprises a terminal 20 attached to the end cap 12A of the hermetic vessel 12. The end cap 12A surrounding the terminal 20 is formed with a stepped part 12C having a specified curvature by seat-pressing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hermetic electric compressor having an electric element and a compression element driven by the electric element in a hermetic container.

[0002]

2. Description of the Related Art A conventional electric compressor of this type, in particular,
In the internal intermediate pressure type multi-stage compression rotary compressor,
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 roller and the vane to become an intermediate pressure, and from the high pressure chamber side of the cylinder through the discharge port and the discharge muffling chamber to a closed container. Is discharged inside. Then, the intermediate pressure refrigerant gas in 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, so that the high temperature and high pressure is achieved. It becomes refrigerant gas, flows into the radiator from the high-pressure chamber side through the discharge port and the discharge muffling chamber, and after radiating heat, it is squeezed by the expansion valve and absorbed by the evaporator, and is sucked into the first rotary compression element. repeat.

When a refrigerant having a large difference in high pressure and low pressure, for example, carbon dioxide (CO ₂ ) as an example of carbon dioxide is used as the refrigerant in the rotary compressor, the refrigerant pressure reaches 12 MPaG in the second rotary compression element which becomes high pressure. ,on the other hand,
8 MPaG at the first rotary compression element on the low stage side,
This becomes the pressure in the closed container.

Further, in such a rotary compressor, a terminal for supplying electric power to the electric element is attached to the end cap of the closed container. FIG. 21 is a sectional view of a terminal 301 portion of the conventional rotary compressor according to FIG. 20. The terminal 301 has an end cap 30 having an asymmetric cross-sectional shape with respect to the center as shown in this figure.
It was welded and fixed to the upper surface of 0.

[0005]

The end cap 300 is deformed in the direction in which the welded portion with the terminal 301 bulges outward under the influence of high internal pressure.
The result of actually measuring the deformation amount of the end cap 300 according to the upper portion of FIG. 20 is shown for each region. In this figure, the amount of deformation in the region indicated by Z4 is 0.2 μm, the amount of deformation in the region indicated by Z5 is increased by 0.5 μm, and the amount of deformation in the region indicated by Z6 is further increased and reaches the maximum of 0.9 μm. .

As described above, since the deformation amount of the terminal 301 portion becomes the largest, there is a problem that cracks and weld peeling occur in the welded portion of the terminal 301 and the end cap 300, and the pressure resistance performance is deteriorated.

The present invention has been made in order to solve the problems of the prior art, and provides a hermetic electric compressor capable of avoiding the disadvantage caused by the deformation of the end cap of the hermetic container. The purpose is to do.

[0008]

That is, the hermetic electric compressor of the present invention comprises an electric element and a compression element driven by the electric element in a hermetic container, and the compression element compresses the refrigerant. It is characterized in that a terminal attached to an end cap of the closed container is provided, and a step having a predetermined curvature is formed on the end cap around the terminal by pushing.

According to the present invention, the hermetically-sealed electric compression device is provided with the electric element and the compression element driven by the electric element in the hermetic container, and the refrigerant is compressed by the compression element and discharged into the hermetic container. In the machine, a terminal attached to the end cap of the closed container is provided, and a step with a predetermined curvature is formed by pushing the end cap around the terminal, so that the rigidity of the end cap near the terminal is increased. In a situation where the pressure inside the closed container is high, as in the case of compressing CO ₂ gas as a refrigerant as described in item 3, it is possible to reduce the amount of deformation of the end cap due to the inside pressure of the closed container and improve the pressure resistance. .

In the hermetic electric compressor according to a second aspect of the present invention, the end cap has a substantially bowl shape, the step has an axially symmetrical shape about the central axis of the end cap, and the terminal has the end. Characterized by being attached to the center of the cap.

According to the second aspect of the present invention, in addition to the above, the end cap has a substantially bowl shape, the step has an axially symmetrical shape about the central axis of the end cap, and the terminal has a shape of the end cap. Since it is attached at the center, it is possible to make the deformation of the end cap of the terminal welded part due to the internal pressure of the closed container uniform, and to avoid the occurrence of cracks and peeling of the welded part due to non-uniform deformation. It is possible to further improve.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a longitudinal sectional view of an internal intermediate pressure type multi-stage (two-stage) compression type rotary compressor 10 provided with first and second rotary compression elements 32, 34 as an embodiment of the hermetic electric compressor of the present invention. 2 is a front view of the rotary compressor 10, FIG. 3 is a side view of the rotary compressor 10, FIG. 4 is another vertical sectional view of the rotary compressor 10, and FIG. 5 is another vertical sectional view of the rotary compressor 10. Is a plan sectional view of the electric element 14 portion of the rotary compressor 10, and FIG. 7 is a rotary compressor 1
The enlarged sectional views of the rotary compression mechanism unit 0 of 0 are respectively shown.

In each figure, 10 is carbon dioxide (C
This is an internal intermediate pressure type multi-stage compression type rotary compressor using O ₂ ) as a refrigerant.
Reference numeral 0 denotes a cylindrical hermetic container 12 made of a steel plate, and an electric element 14 arranged and housed above the inner space of the hermetic container 12.
And the electric element 14 disposed below the electric element 14.
First rotary compression element 32 driven by the rotary shaft 16 of
The rotary compression mechanism portion 18 includes the (first stage) and the second rotary compression element 34 (second stage). The height dimension of the rotary compressor 10 of the embodiment is 220 mm (outer diameter 120 mm), and the height dimension of the electric element 14 is about 80 mm.
(Outer diameter 110 mm), the height dimension of the rotary compression mechanism portion 18 is about 70 mm (outer diameter 110 mm), and the distance between the electric element 14 and the rotary compression mechanism portion 18 is about 5 mm. The excluded volume of the second rotary compression element 34 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, a step portion (step) 12C having a predetermined curvature is formed in the end cap 12B around the terminal 20 by press forming in an annular shape having an axially symmetric shape around the central axis of the end cap 12B. Has been done. In addition, the terminal 20 has a circular glass portion 20 </ b> A to which the electrical terminal 139 is attached, and the glass portion 20 </ b> A.
It is composed of an iron-made (S25C to S45C) mounting portion 20B that is formed around A and projects obliquely outward and downward in a brim shape, and this also has an axially symmetrical shape about the central axis of the end cap 12B. . The thickness of the mounting portion 20B is 2.
The range is 4 ± 0.5 mm (1.9 mm or more and 2.9 mm or less). 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.

Here, when the thickness of the mounting portion 20B of the terminal 20 becomes thinner than 1.9 mm, the strength (pressure resistance) against the high pressure (intermediate pressure) of the refrigerant gas in the closed container 12 is obtained.
Is insufficient, and a crack occurs in the mounting portion 20B itself. on the other hand,
If the thickness of the mounting portion 20B is made thicker than 2.9 mm, a large amount of heat is required when welding to the closed container 304 this time, and there is a concern that the glass portion 20A will be adversely affected. Therefore, in the embodiment, based on this, the terminal 20
The thickness of the mounting portion 20B is set within the range of 2.4 ± 0.5 mm, and the increase in the amount of heat necessary for welding and fixing is suppressed while sufficiently securing the pressure resistance of the terminal 20.

The end cap 12A is a closed container 1.
Terminal 2 under the influence of high pressure (intermediate pressure) in 2
The welded portion with 0 is deformed in the direction of bulging outward. Figure 1
The result of actually measuring the deformation amount of the end cap 12A according to No. 9 is shown for each region. In this figure, the amount of deformation in the region indicated by Z1 is 0.05 μm, the amount of deformation in the region indicated by Z2 is 0.2 μm, and the amount of deformation in the region indicated by Z3 is the maximum of 0.
It was 25 μm. This is a result of the rigidity of the end cap 12A in the vicinity of the terminal 20 being increased by the step portion 12C, which is an extremely small value compared with the amount of deformation of the conventional end cap described above.

Further, since the terminal 20 is fixed to the center of the substantially bowl-shaped end cap 12A and the step portion 12C is also formed around it, the deformation amount itself is also the terminal 2.
They are evenly distributed in concentric circles centered on 0.

As a result, in the present invention, the end cap 12A due to the internal pressure of the closed container 12 is compressed in the situation where the internal pressure of the closed container 12 is increased by compressing CO ₂ gas as a refrigerant.
It is possible to reduce the amount of deformation and improve the breakdown voltage. In addition, the terminal 20 due to the internal pressure of the closed container 12
Uniformize the deformation of the end cap 12A at the welded part of
It is possible to prevent cracks and peeling of the welded portion due to uneven deformation, and to further improve the pressure resistance.

On the other hand, the electric element 14 has a stator 22 annularly mounted along the inner peripheral surface of the upper space of the hermetic container 12, and a rotor 24 inserted and arranged inside the stator 22 with a slight gap. Consists of. This rotor 24
Is fixed to a 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 support member that also serves as a bearing for the rotary shaft 16 by closing the upper opening surface of the upper cylinder 38 and the lower opening surface of the lower cylinder 40. 54 and the 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 below by four 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.

Here, the lower support member 56 is made of an iron-based sintered material (which may be a casting), and the lower cover 6
The surface on which 8 is attached (lower surface) is processed to have a flatness of 0.1 mm or less and then subjected to steam treatment. 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 is made of a substantially donut-shaped circular steel plate having a diameter of 0 mm or less (most preferably 6 mm in the embodiment) and having a hole through which the bearing 54A of the upper support member 54 passes. In the state where the beaded gasket 124 is sandwiched between them, the peripheral portion is fixed to the upper support member 54 from above by the four main bolts 78 ... Through the gasket 124. The tips of the main bolts 78 ... Are screwed into the lower support member 56.

By making the thickness of the upper cover 66 to be such a size, it is possible to withstand the pressure of the discharge muffling chamber 62, which is higher than the pressure inside the closed container 12, and to achieve the downsizing, and 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 the gas leak, and it is possible to increase 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, 127 is a discharge valve of the second rotary compression element 34 that 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 passage 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 that communicates with the communication hole 133 of the intermediate partition plate 36 is formed on the (suction side). Further, as shown in FIG. 7, an oil hole 80 is formed in the rotary shaft 16 in the vertical direction about the shaft center.
And a lateral oil supply hole 82 communicating with the oil hole 80,
84 (also formed on the vertical eccentric portions 42, 44) is formed, and the opening on the inner peripheral surface side of the through hole 131 of the intermediate partition plate 36 is an oil hole through these oil supply holes 82, 84. It communicates with 80.

As will be described later, since the inside pressure of the closed container 12 becomes an intermediate pressure, it becomes difficult to supply the oil into the upper cylinder 38 which becomes a high pressure in the second stage. However, the intermediate partition plate 36 is provided. , Pumped up from the oil sump at the bottom of the closed container 12 to raise the oil hole 80,
The oil discharged from No. 4 enters the through hole 131 of the intermediate partition plate 36 and is supplied to the suction side (suction port 161) of the upper cylinder 38 from the communication holes 133 and 134.

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, the back pressure gas leak from the guide groove 70 can be prevented.

On the other hand, inside the upper cylinder 38, a guide groove 70 for accommodating the vane 50 and an accommodating portion 70A located outside the guide groove 70 for accommodating a spring 76 as a spring member are formed. 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. A back pressure chamber (not shown) communicates with the guide groove 70.
The discharge pressure (high pressure) of the second rotary compression element 34 is applied as a back pressure to the spring 76 of the plug 137.
The side is at high pressure, and the closed container 12 side is at intermediate pressure.

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 the above dimensional relationship, the plug 1
As in the case where 37 is press-fitted and fixed in the accommodating portion 70A, it is possible to avoid the inconvenience that the upper cylinder 38 is deformed and the sealing performance between the upper cylinder 38 and the upper support member 54 is deteriorated, resulting in deterioration of performance. become. Even with such a clearance fit, 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. Even if the plug 138 is moved in the direction of being pushed out from the storage portion 70A, the O-ring 138 is still positioned and sealed inside the storage portion 70A at the time when the movement is blocked by coming into contact with the closed container 12, so that the function of the plug 138 is No problems arise.

By the way, the connecting portion 90 which connects the upper and lower eccentric portions 42 and 44 integrally formed 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 connecting portion 90 connecting the four has the same axial center as that of the rotary shaft 16, but its cross-sectional shape is such that its wall thickness is increased in the direction orthogonal to the eccentric direction of the vertical eccentric portions 42, 44 (hatching in the drawing). Part).

As a result, the cross-sectional area of the connecting portion 90 which connects the vertical eccentric portions 42 and 44 integrally provided on the rotary shaft 16 is increased, the second moment of area is increased, and the strength (rigidity) is increased, resulting in 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, as the refrigerant, carbon dioxide (CO ₂ ) as an example of carbon dioxide which is a natural refrigerant is used in consideration of flammability and toxicity, and it is an oil as a lubricating oil. As the oil, 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 the container body 1 of the closed container 12.
It is attached via a bracket 148 on the accumulator side to a bracket 147 on the closed container side welded and fixed to the upper side surface of 2A. The bracket 148 extends upward from the bracket 147 and holds the substantially central portion of the accumulator 146 in the vertical direction. In this state, the accumulator 146 is arranged along the side of the closed container 12. The refrigerant introduction 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 is in the form of being close to the refrigerant introduction 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 38 and the lower support member 4
Refrigerant introduction pipes 92 and 94 communicating with the suction passages 58 and 60 of 0 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 air tightness test is performed in the completion inspection in the manufacturing process of the rotary compressor 10. Screw groove 152
You can easily screw the test pipe with. In particular, the upper and lower sleeves 141 and 142 are
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: 4 MPaG) sucked from the suction port 162 to the low pressure chamber side of the lower cylinder 40 via the refrigerant introduction pipe 94 and the suction passage 60 formed in the lower support member 56. ) The refrigerant gas is
The intermediate pressure (M
P1: 8 MPaG), and is discharged from the high pressure chamber side of the lower cylinder 40 into the closed container 12 from the discharge port 41, the discharge muffling chamber 64 formed in the lower support member 56, the communication passage 63, and the intermediate discharge pipe 121.

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 value).
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 to become high-temperature high-pressure refrigerant gas (second-stage discharge pressure HP: 12 MPa.
G) From the high pressure chamber side, the gas 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 has risen to approximately + 100 ° C., and the high-temperature and high-pressure refrigerant gas radiates heat to heat the water in the hot water storage tank to approximately +
It produces hot water at 90 ° C.

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.

In particular, in an environment of low outside temperature, frost is formed on the evaporator 157 by such heating operation. 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.

As described above, since the intermediate pressure refrigerant gas discharged from the first rotary compression element 32 is taken out from the closed container 12 to defrost the evaporator 157, the second rotary compression element is used. It is possible to prevent the pressure reversal phenomenon between the discharge (high pressure) and the suction (intermediate pressure) of the second rotary compression element 34 which occurs when the high pressure refrigerant discharged from the compressor 34 is supplied to the evaporator 157 without being decompressed. become able to.

The hermetic electric compressor is not limited to the internal intermediate pressure type multi-stage compression type rotary compressor as in the embodiment, but the present invention is also effective for a single cylinder rotary compressor and the like. Further, although CO ₂ refrigerant is used in the embodiment, the present invention is effective for other refrigerants in claims 1 and 2.

[0058]

As described above in detail, according to the present invention, an electric element and a compression element driven by the electric element are provided in the closed container, and the refrigerant is compressed by the compression element in the closed container. In a hermetic electric compressor that discharges to, equipped with a terminal attached to the end cap of the hermetic container,
Since a step having a predetermined curvature is formed on the end cap around the terminal by pushing the end cap, the rigidity of the end cap near the terminal is increased.
_{In the} situation where the pressure inside the closed container is high as in the case where ₂ gas is compressed as a refrigerant, the amount of deformation of the end cap due to the inside pressure of the closed container can be reduced and the pressure resistance can be improved.

According to the second aspect of the present invention, in addition to the above, the end cap has a substantially bowl shape, and the step has a shape symmetrical with respect to the center axis of the end cap, and the terminal has the shape of the end cap. Since it is attached at the center, it is possible to make the deformation of the end cap of the terminal welded part due to the internal pressure of the closed container uniform, and to avoid the occurrence of cracks and peeling of the welded part due to non-uniform deformation. It is possible to further improve.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a rotary compressor as an embodiment of a hermetic electric compressor 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 showing the relationship between the cross section of the terminal portion of the rotary compressor of FIG. 1 and the deformation amount of the end cap.

FIG. 20 is a diagram showing a relationship between a cross section of a terminal portion of a conventional rotary compressor and a deformation amount of an end cap.

[Explanation of symbols]

10 Rotary compressor 12 airtight container 12A end cap 12D mounting hole 14 Electric elements 16 rotation axes 18 Rotary compression mechanism 20 terminals 20A glass part 20B mounting part 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 76 Spring (Spring member) 78,129 Main bolt 90 Connection 92,94 Refrigerant introduction pipe 96 Refrigerant discharge pipe 131 Through hole (oil supply passage) 132 sealing material 133,134 communication holes 137 plug 138 O-ring 141, 142, 143, 144 Sleeves 146 Accumulator 147,148 Bracket 151 Tsuba 153 water heater 154 gas cooler 156 expansion valve 157 evaporator 158 Defrost Tube 159 Solenoid valve

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Haruhisa Yamazaki             2-5-3 Keihan Hondori, Moriguchi City, Osaka Prefecture             Within Yo Denki Co., Ltd. (72) Inventor Kenzo Matsumoto             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 Takayasu Saito             2-5-3 Keihan Hondori, Moriguchi City, Osaka Prefecture             Within Yo Denki Co., Ltd. (72) Inventor Toshiyuki Ehara             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 Takashi 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. F-term (reference) 3H003 AA05 AB04 AC03 AD01 CF02

Claims (3)

[Claims] 1. A hermetic electric compressor that includes an electric element in a hermetic container and a compression element driven by the electric element, and compresses a refrigerant by the compression element and discharges the refrigerant into the hermetic container. A hermetic electric compressor, comprising: a terminal attached to an end cap of the hermetic container, wherein a step having a predetermined curvature is formed on the end cap around the terminal by pushing the terminal. 2. The end cap has a substantially bowl shape, the step has a shape symmetrical with respect to a center axis of the end cap, and the terminal is attached to the center of the end cap. The hermetic electric compressor according to claim 1, which is characterized in that. 3. The hermetic electric compressor according to claim 1, wherein the compression element compresses CO ₂ gas as a refrigerant.