JP2004251150A - Multistage compression type rotary compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve compression efficiency and reliability by increasing the heat insulation of a cylinder in a multistage compression type rotary compressor. <P>SOLUTION: The rotary compressor comprises: a lower cylinder (first cylinder) 40 and an upper cylinder (second cylinder) 38 constituting first and second rotary compression elements 32, 34, respectively; an intermediate partition board 36 interposed between the cylinders 38, 40 to partition the first and second rotary compression elements 32, 34; an upper support member (second support member 54) closing opening faces of the upper and lower cylinders 38, 40 and having a bearing of a rotating shaft 16 of an electric element 14, and a lower support member 56 (first support member); and a heat insulating plate 140 having an insulation property is interposed between the upper cylinder 38 and the upper support member 54, and a heat insulating plate 141 having an insulation property is interposed between the upper cylinder 38 and the intermediate partition board 36. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention includes first and second rotary compression elements driven by drive elements in a closed container, and sucks and compresses the refrigerant compressed by the first rotary compression element into the second rotary compression element. The present invention relates to a multi-stage compression type rotary compressor.
[0002]
[Prior art]
In a conventional multi-stage compression type rotary compressor of this type, for example, a vertical type internal intermediate pressure type multi-stage (two-stage) compression type rotary compressor, an electric element as a driving element is provided above the internal space of the closed vessel. On the lower side, there is provided a rotary compression mechanism section including first and second rotary compression elements driven by the rotary shaft of the electric element. Further, the second rotary compression element is provided above the first rotary compression element, and an intermediate partition plate is sandwiched between the first rotary compression element and the second rotary compression element.
[0003]
That is, the first rotary compression element and the second rotary compression element include an intermediate partition plate, an upper cylinder and a lower cylinder disposed above and below the intermediate partition plate, and a phase difference of 180 degrees between the upper and lower cylinders. An upper and lower roller that is eccentrically rotated by an upper and lower eccentric part provided on the rotating shaft, a vane that abuts on the upper and lower rollers to partition the inside of the upper and lower cylinders into a low pressure chamber side and a high pressure chamber side, respectively, It comprises an upper support member and a lower support member as support members that also close the upper opening surface and the lower opening surface of the lower cylinder and also serve as bearings for the rotating shaft.
[0004]
Refrigerant gas is sucked into the low pressure chamber side of the cylinder from the suction port of the first rotary compression element, is compressed by the operation of the rollers and the vanes and becomes an intermediate pressure, and is discharged from the high pressure chamber side of the cylinder through the discharge port and the discharge silence chamber. Discharged into a closed container. 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 high-pressure The refrigerant gas is configured to flow from the high-pressure chamber side to an external radiator through a discharge port and a discharge muffling chamber (for example, see Patent Document 1).
[0005]
[Patent Document 1]
Japanese Patent No. 2507077 [0006]
[Problems to be solved by the invention]
By the way, when a refrigerant having good thermal conductivity such as carbon dioxide and a remarkable rise in temperature during compression is used for the rotary compressor, the cylinder which is a compression chamber is discharged to the discharge muffling chamber or the intermediate space in the closed container. Therefore, there is a problem that the compression efficiency and the reliability of the compressor are lowered as a result of being easily heated by the heat of the pressure refrigerant.
[0007]
The present invention has been made to solve such technical problems, and an object of the present invention is to improve the heat insulating properties of a cylinder to improve the compression efficiency and reliability of a multistage compression type rotary compressor.
[0008]
[Means for Solving the Problems]
That is, in the multistage compression type rotary compressor according to the first aspect of the present invention, the first and second cylinders for forming the first and second rotary compression elements, respectively, and the rotary compression elements interposed between the cylinders. , And first and second support members that close the opening surfaces of the first and second cylinders and have bearings for the rotating shaft of the drive element, respectively, the first cylinder, and / or Alternatively, since a heat-insulating plate is provided between the second cylinder and the intermediate partition plate and / or the support member, the cylinder and the refrigerant sucked into the cylinder are less likely to be heated.
[0009]
According to the second aspect of the present invention, in addition to the above-described invention, since a gap is formed between the second support member and the plate, the plate is more difficult to be heated, and the heat insulation of the second cylinder is improved.
[0010]
In the multistage compression type rotary compressor according to the third aspect of the present invention, the first and second cylinders for forming the first and second rotary compression elements, respectively, and the rotary compression elements are interposed between the cylinders to partition the rotary compression elements. An intermediate partition plate, and first and second support members that respectively close the opening surfaces of the first and second cylinders and have bearings for the rotation shaft of the driving element, and include at least a second cylinder and a second cylinder. Since the support member is made of a different metal material, heat conduction between the second cylinder and the second support member can be suppressed.
[0011]
According to the fourth aspect of the invention, carbon dioxide is used as a refrigerant in addition to each of the above-mentioned aspects, so that further effects can be expected.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an embodiment 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 including first and second rotary compression elements 32 and 34 as an embodiment of a multi-stage compression type rotary compressor of the present invention. FIG. 2 is an enlarged view of the rotary compression mechanism 18 of the rotary compressor 10 of FIG. 1, and FIG. 3 is a plan sectional view of the rotary compressor 10.
[0013]
In each of the figures, reference numeral 10 denotes an internal intermediate pressure type multi-stage (two-stage) compression type rotary compressor mounted in an engine room of a vehicle such as an electric vehicle (HEV or PEV), which uses carbon dioxide (CO ₂ ) as a refrigerant. ing. The compressor 10 has a cylindrical hermetic container 12, an electric element 14 as a driving element disposed and housed above the internal space of the hermetic container 12, and is disposed below the electric element 14. The rotary compression mechanism 18 includes a first rotary compression element 32 (first stage) and a second rotary compression element 34 (second stage) driven by the shaft 16.
[0014]
The closed container 12 of the embodiment is formed of an aluminum material, and has a container main body 12A for housing the electric element 14 and the rotary compression mechanism 18, and a substantially bowl-shaped end cap (lid) for closing an upper opening of the container main body 12A. 12B. A circular mounting hole 12D is formed at the center of the upper surface of the end cap 12B, and a terminal (wiring omitted) 20 for supplying electric power to the electric element 14 is mounted in the mounting hole 12D. Reference numeral 21 denotes an external wiring connected to the terminal 20. In addition, the upper end of the container body 12A is expanded outward and is formed thicker than the other parts. The lower end of the end cap 12B is inserted into the inner wall of the expanded portion 13A, and the inner wall of the expanded portion 13A is inserted. The sealed container 12 is formed by fixing the end cap 12B by arc welding from the outside in the inserted state.
[0015]
The terminal 20 is entirely covered with a metal (aluminum or the like) terminal cover 100 as a cover for protecting the terminal 20. A plurality of bolt holes are formed around the terminal cover 100. Further, a bolt groove is formed in the end cap 12B corresponding to the bolt hole of the terminal cover 100, and the terminal cover 100 is arranged so that the bolt hole of the terminal cover 100 and the bolt groove of the end cap 12B coincide with each other. The terminal cover 100 is attached to the center of the upper end of the end cap 12B by screwing and fixing the bolt 102 into the bolt groove from above.
[0016]
The electric element 14 is a so-called magnetic pole concentrated winding type DC motor, and is inserted into the stator 22 annularly attached along the inner peripheral surface of the upper space of the closed casing 12 with a slight interval provided inside the stator 22. And an installed rotor 24. The rotor 24 is fixed to the rotating shaft 16 that extends vertically through the center. The stator 22 is formed by laminating donut-shaped electromagnetic steel sheets, and is wound around the inner surface of the closed container 12 by shrink-fitting, and is wound around the teeth of the laminated body 26 by a direct winding (concentrated winding) method. Stator coil 28. The rotor 24 is formed of a laminated body 30 of electromagnetic steel sheets similarly to the stator 22, and is formed by inserting a permanent magnet MG into the laminated body 30.
[0017]
An oil pump 99 is formed at the lower end of the rotary shaft 16 as oil supply means. The oil pump 99 sucks up lubricating oil from an oil reservoir formed at the bottom of the sealed container 12, and passes through an oil hole (not shown) formed in the center of the rotating shaft 16 in a vertical direction. Sliding of the upper and lower eccentric portions 42 and 44 and the first and second rotary compression elements 32 and 34 from lateral oil supply holes 82 and 84 (also formed on the upper and lower eccentric portions 42 and 44) communicating with the oil holes. Oil is supplied to the parts and the like. As a result, the first and second rotary compression elements 32 and 34 are prevented from being worn and sealed.
[0018]
An intermediate partition plate 36 is held between the first rotary compression element 32 and the second rotary compression element 34. The intermediate partition plate 36 is interposed between the upper cylinder 38 and the lower cylinder 40 to partition the first and second rotary compression elements 32 and 34. That is, the first rotary compression element 32 and the second rotary compression element 34 include an intermediate partition plate 36, an upper cylinder (second cylinder) 38 disposed above and below the intermediate partition plate 36, and a lower cylinder (second cylinder). And the upper and lower cylinders 38, 40, and upper and lower rollers 46, 48, which are eccentrically rotated by the upper and lower eccentric portions 42, 44 provided on the rotating shaft 16 with a phase difference of 180 degrees. A vane (not shown) which abuts the upper and lower rollers 46 and 48 to partition the inside of the upper and lower cylinders 38 and 40 into a low pressure chamber side and a high pressure chamber side, respectively, and an upper opening surface of the upper cylinder 38 and a lower side of the lower cylinder 40. An upper support member (second support member) 54 and a lower support member (first support member) 56 as support members that also serve as bearings for the rotating shaft 16 by closing the opening surface.
[0019]
In the upper support member 54 and the lower support member 56, a suction passage 60 (the upper suction passage is shown in the drawing) communicating with the insides of the upper and lower cylinders 38 and 40 at a suction port 161 (the lower suction port is not shown). ), And discharge muffling chambers 62 and 64 formed by partially recessing and closing the recess with the upper cover 66 and the lower cover 68.
[0020]
The upper cover 66 is made of an aluminum material, and has an outer peripheral surface formed so as to contact the inner wall of the closed container 12. Further, the outer peripheral surface of the upper cover 66 is extended in the vertical direction (axial direction of the rotation shaft; upward direction in the embodiment) as shown in the figure, and the expanded outer peripheral surface and the sealed container 12 are tack-welded. And is attached to the closed container 12. The upper cover 66 closes the upper opening of the concave portion of the upper support member 54, and communicates with the inside of the upper cylinder 38 of the second rotary compression element 34 via a discharge port (not shown). In addition to defining the discharge muffling chamber 62, the electric element 14 is provided above the upper cover 66 at a predetermined interval from the upper cover 66.
[0021]
The upper cover 66 is formed of a substantially donut-shaped circular aluminum plate having a hole through which the bearing 54A of the upper support member 54 penetrates, and its peripheral portion is formed by four main bolts 78. It is fixed to the support member 54. The main bolts 78 penetrate through the upper support member 54, and their ends are screwed into the lower support member 56 to form the upper cover 66, the upper support member 54, the upper cylinder 38, the intermediate partition plate 36, and the lower cylinder. 40 and the lower support member 56 are integrated. The lower cover 68 is fixed to the lower support member 56 with bolts.
[0022]
Here, as shown in FIG. 2, the upper and lower surfaces of the upper cylinder 38, that is, between the upper cylinder 38 and the upper support member 54, and between the upper cylinder 38 and the intermediate partition plate 36 have heat insulating properties. Heat insulation plates 140 and 141 are interposed. These heat insulating plates 140 and 141 are formed by rolling a heat-insulating metal having a low thermal conductivity, for example, a stainless steel plate into a 0.3 to 0.5 mm plate shape. A hole for inserting the rotating shaft 16 is formed at the center of the heat insulating plates 140 and 141, and has a substantially donut shape as a whole.
[0023]
A communication hole 133 described later is formed in the heat insulating plate 141, and is connected to a communication hole 134 formed in the cylinder 38 at the upper end of the communication hole 133. On the other hand, a communication hole (vertical hole) (not shown) is formed in the heat insulating plate 140, and the lower end of the communication hole communicates with a discharge port (not shown) provided in the upper cylinder 38. The upper end of the communication hole communicates with a discharge muffling chamber 62 formed in the upper support member.
[0024]
Due to the presence of the heat insulating plate 140, the heat of the high-temperature and high-pressure refrigerant gas discharged into the discharge muffling chamber 62 formed in the upper support member 54 provided above the upper cylinder 38 and the intermediate gas discharged into the closed container 12 It becomes difficult for the heat of the pressure refrigerant gas to be transmitted to the upper cylinder 38. Thus, it is possible to prevent the upper cylinder 38 from being heated by the high-pressure and high-temperature refrigerant gas discharged into the discharge muffling chamber 62 and the intermediate-pressure refrigerant gas discharged into the closed container 12.
[0025]
Further, a slight gap is formed between the heat insulating plate 140 and the upper support member 54. This makes it difficult for the heat of the upper support member 54 to be transmitted to the heat insulating plate 140 and makes it more difficult for the upper cylinder 38 to be heated, so that the compression efficiency of the second rotary compression element 34 can be improved. .
[0026]
Further, the heat from the first rotary compression element 32 is less likely to be transmitted to the upper cylinder 38 due to the presence of the heat insulating plate 141. Thus, it is possible to avoid the problem that the upper cylinder 38 is heated by the refrigerant gas or the like compressed by the first rotary compression element 32.
[0027]
As a result, the upper cylinder 38 is heated by the high-temperature and high-pressure refrigerant discharged into the discharge muffling chamber 62 and the heat from the first rotary compression element 32, thereby heating the refrigerant sucked into the upper cylinder 38. Since it can be suppressed or avoided, the compression efficiency of the second rotary compression element 34 can be improved. Thereby, the reliability of the compressor 10 is improved.
[0028]
In particular, when a refrigerant having good thermal conductivity such as carbon dioxide (CO ₂ ) and a remarkable temperature rise during compression is used as in the present embodiment, the upper cylinder 38 is placed in the closed container 12 or the first cylinder. The refrigerant compressed by the rotary compression element 32, and further, the refrigerant compressed by the second rotary compression element 34 and discharged to the discharge muffling chamber 62, etc., is very easily heated, and is compressed by the first rotary compression element 32. Even if the refrigerant is cooled by temporarily passing the refrigerant through a refrigerant introduction portion 92 formed outside the closed container 12, and then sucked into the upper cylinder 38 of the second rotary compression element 34, the upper cylinder 38 Is heated, the sucked refrigerant is heated by the upper cylinder 38. Therefore, the effect of cooling the refrigerant by passing it through the outside of the closed container 12 cannot be reduced or obtained.
[0029]
However, since the upper cylinder 38 is not heated by providing the heat insulating plates 140 and 141, the cooled refrigerant itself is compressed by the upper cylinder 38 without being subjected to the heating action. The efficiency is significantly improved.
[0030]
On the other hand, the intermediate partition plate 36 has a substantially donut shape, and an oil supply hole 131 is formed in the intermediate partition plate 36. The oil supply hole 131 is formed by covering the groove formed in the upper surface of the intermediate partition plate 36 (the surface on the upper cylinder 38 side) from the inner peripheral surface to the outside in a predetermined range in the radial direction with the heat insulating plate 141. I have.
[0031]
The above-described communication hole (vertical hole) 133 is formed in the heat insulating plate 141 at a position corresponding to the end of the oil supply hole 131 on the closed container 12 side. The upper cylinder 38 is provided with an injection communication hole 134 for communicating the communication hole 133 of the heat insulating plate 141 with the suction port 161 (the suction side of the second rotary compression element 34). Here, the opening of the oil supply hole 131 of the intermediate partition plate 36 on the rotation shaft 16 side communicates with an oil hole (not shown) through oil supply holes 82 and 84 formed in the rotation shaft 16.
[0032]
In this case, as will be described later, the inside of the sealed container 12 has an intermediate pressure, so that it becomes difficult to supply oil into the upper cylinder 38, which becomes high in the second stage. The oil that has been pumped up from the oil reservoir at the bottom of the closed container 12 and rises through an oil hole (not shown) and has come out of the oil supply holes 82 and 84 enters the oil supply hole 131 of the intermediate partition plate 36 and passes through the communication holes 133 and 134. The air is supplied to the suction side (suction port 161) of the upper cylinder 38.
[0033]
As the refrigerant, the above-mentioned carbon dioxide (CO ₂ ), which is a natural refrigerant in consideration of flammability and toxicity, is used for the earth environment, is used. Existing oils such as alkylbenzene oil, ether oil, ester oil, and PAG (polyalkyl glycol) are used.
[0034]
In the container main body 12A of the closed container 12, a position corresponding to the suction passage (not shown) of the upper support member 54 and immediately below the electric element 14, and the position corresponding to the suction passage 60 of the lower support member 56 and the discharge muffling chamber 62. Further, the above-described refrigerant introduction part 92, and the refrigerant introduction part 94 and the refrigerant discharge part 96 are formed respectively.
[0035]
The refrigerant introduction portion 92 is discharged into the closed container 12 between the thick portion 13B integrally formed with the container body 12A of the closed container 12 and the outer surface of the thick portion 13B and between the thick portion 13B. It is constituted by a lid member 112 (relief means) which constitutes a refrigerant introduction passage 92A for sucking the drawn refrigerant into the second rotary compression element 34. That is, grooves having a semicircular cross section are formed on the opposing surfaces of the thick portion 13B formed on the container body 12A and the lid member 112, and the thick portions 13B and the lid are formed by opposing these grooves. A coolant introduction passage 92A as a passage as shown in FIG.
[0036]
In addition, a communication pipe 93A for communicating the inside of the closed container 12 and the refrigerant introduction passage 92A to the thick portion 13B of the container body 12A, a suction passage (not shown) of the second rotary compression element 34 and a refrigerant introduction passage 92A. A communication pipe 93B that communicates with is provided. A packing (seal material) 114 is provided between the thick portion 13B and the lid member 112 (the entire periphery of the coolant introduction passage 92A), and the lid member 112 is provided via the packing 114 related to the thick portion 13B. It is fixed by bolts 120.
[0037]
The lid member 112 is made of an aluminum material similarly to the container body 12A. The thick portion 13B and the lid member 112 are always in close contact with each other to seal the refrigerant introduction passage 92A from the outside. However, the elasticity of the lid member 112 itself and the diameter (tightening strength) of the bolts 120. By setting, when the pressure of the refrigerant in the closed container 12 rises to a predetermined value, the pressure of the refrigerant flowing into the refrigerant introduction passage 92A causes the lid member 112 itself or the bolt 120 so that the lid member 112 is separated outward. Are deformed, and a gap is formed between the thick portion 13B and the lid member 112. The gap connects the inside and the outside of the refrigerant introduction passage 92 </ b> A, and the medium-pressure refrigerant in the passage escapes to the outside of the closed container 12.
[0038]
With such a configuration, a gap is formed between the lid member 112 and the thick portion 13B when the pressure of the intermediate-pressure refrigerant in the closed container 12 is abnormally increased, and the refrigerant is introduced. Since the refrigerant gas in the sealed container 12 can be released to the outside from the passage 92A, the durability of the compressor 10 is improved, and the reliability can be improved.
[0039]
On the other hand, a support leg 150 is attached to the lower surface of the container body 12A of the closed container 12. The support legs 150 are formed of a thick aluminum plate, and protrude outward from the lower surface of the container body 12A. An elastic mounting 204 of the support device 200 described below is attached to a lower surface of the support leg 150.
[0040]
The above-described support device 200 for supporting the rotary compressor 10 is configured around the closed container 12 of the rotary compressor 10. The support device 200 is provided at a predetermined interval outside the closed container 12 and is attached to the soundproof wall 202 surrounding the closed container 12 and the support legs 150 on the lower surface of the container body 12A of the closed container 12. And an upper elastic support member 207 provided in a hole 206 formed on the upper surface of the soundproof wall 202.
[0041]
The soundproof wall 202 is provided in order to avoid the inconvenience that noise generated during operation of the electric element 14 leaks to the outside, and has a substantially cylindrical shape that covers the outside of the closed casing 12 and is provided inside the engine room of the vehicle. Fixed to. A substantially circular hole 206 is formed at the upper end of the soundproof wall 202, and an upper elastic support member 207 is attached inside the hole 206.
[0042]
The elastic mounting 204 attached to the support legs 150 on the lower surface of the container body 12A is formed to support the lower part of the closed container 12, is made of an elastic material such as hard rubber, and is attached to a bolt (not shown). Attached to the support leg 150. The lower surface of the elastic mounting 204 is fixed to the soundproof wall 202.
[0043]
On the other hand, the upper elastic support member 207 mounted in the hole 206 of the soundproof wall 202 is made of an elastic material such as hard rubber, and has a curved portion 208 which is curved so as to undulate over the entire circumference. I have. The curved portion 208 absorbs the vibration transmitted from the terminal cover 100, and does not transmit the vibration to the soundproof wall 202. An insertion hole 209 for inserting the terminal cover 100 is formed in the center of the upper elastic support member 207. The terminal cover 100 is inserted through the insertion hole 209, and is fixed to the upper elastic support member 207 all around. Thereby, the terminal cover 100 is attached to the inner peripheral surface of the hole 206 of the soundproof wall 202 via the upper elastic support member 207. That is, the terminal cover 100 is supported by the soundproof wall 202 via the upper elastic support member 207.
[0044]
As described above, the lower portion of the rotary compressor 10 is supported by the elastic mounting 204 provided at the lower portion of the sealed container 12 of the rotary compressor 10, and the upper end of the sealed container 12 is supported by the upper elastic support member 207. The disadvantage that the upper portion becomes unstable in the rotary compressor 10 can be eliminated. Further, by forming these with elastic members, it becomes possible to make it difficult to transmit the vibration generated from the rotary compressor 10 to the soundproof wall 202.
[0045]
Next, the operation of the rotary compressor 10 of the present invention having the above configuration will be described. When the stator coil 28 of the electric element 14 of the rotary compressor 10 is energized through the wiring 21 and the terminal 20, the electric element 14 is activated and the rotor 24 rotates. By this rotation, the upper and lower rollers 46 and 48 fitted to the upper and lower eccentric portions 42 and 44 provided integrally with the rotating shaft 16 eccentrically rotate inside the upper and lower cylinders 38 and 40.
[0046]
As a result, the low-pressure refrigerant gas sucked into the low-pressure chamber side of the cylinder 40 from the suction port (not shown) through the refrigerant introduction portion 94 and the suction passage 60 formed in the lower support member 56 is transferred to the roller 48 and the vane (not shown). Is compressed to an intermediate pressure, and is discharged from the intermediate discharge pipe 121 into the closed container 12 through a communication passage (not shown) from the high pressure chamber side of the lower cylinder 40. Thereby, the inside of the sealed container 12 has an intermediate pressure.
[0047]
Then, the intermediate-pressure refrigerant gas in the closed container 12 flows into the communication pipe 93 </ b> A of the refrigerant introduction part 92. In this case, when the pressure of the intermediate-pressure refrigerant gas flowing into the communication pipe 93A is lower than a set value, the illustration formed in the upper support member 54 from the communication pipe 93A through the refrigerant introduction passage 92A and the communication pipe 93B. The air is sucked from the suction port 161 to the low-pressure chamber side of the upper cylinder 38 of the second rotary compression element 34 via the suction passage that is not used. At this time, the refrigerant gas discharged into the closed container 12 is cooled by passing the refrigerant gas through a refrigerant introduction pipe 92 provided outside the closed container 12. The refrigerant sucked into the low-pressure chamber side of the upper cylinder 38 is compressed in the second stage by the operation of the roller 46 and a vane (not shown) to become high-pressure and high-temperature refrigerant gas, and passes through the discharge port (not shown) from the high-pressure chamber side. The refrigerant is discharged from the refrigerant discharge portion 96 to the outside through the discharge muffling chamber 62 formed in the upper support member 54.
[0048]
On the other hand, when the pressure of the intermediate-pressure refrigerant gas compressed by the first rotary compression element 32 and discharged into the closed container 12 rises to the above-described set value, the refrigerant introduction passage extends from the communication pipe 93A of the refrigerant introduction section 92 to the refrigerant introduction passage. Due to the pressure of the refrigerant flowing into 92A, the thick portion 13B is formed as described above (the lid member 112 is deformed by being pushed outward, or the lid member 112 is moved outward against the tightening force of the bolts 120...) A gap is formed between the cover member 112 and the cover member 112. Then, a part of the refrigerant gas in the closed container 12 escapes from the gap to the outside.
[0049]
As a result, the refrigerant gas in the closed container 12 that has abnormally risen as described above can be escaped to the outside to avoid the occurrence of damage due to the abnormal rise in pressure. Further, since the pressure in the closed container 12 is regulated to be lower than the set value due to the outflow, the pressure is sucked into the second rotary compression element 34 through the refrigerant introduction passage 92A and the communication pipe 93B, and the second rotary compression element 34 It is possible to avoid a disadvantage that the pressure of the compressed refrigerant is excessively increased.
[0050]
When the pressure in the closed container 12 falls below the set value by the relief function, the gap formed between the thick portion 13B and the lid member 112 is closed.
[0051]
As described above, since the upper and lower surfaces of the upper cylinder 38 of the second rotary compression element 34 are closed by the heat insulating plates 140 and 141 having heat insulating properties, the problem of the upper cylinder 38 being heated can be prevented. become.
[0052]
Thus, the upper cylinder 38 is heated by the high-temperature and high-pressure refrigerant discharged into the discharge muffling chamber 62 and the heat from the first rotary compression element 32, thereby heating the refrigerant sucked into the upper cylinder 38. Since it can be suppressed or avoided, the compression efficiency of the second rotary compression element 34 can be improved.
[0053]
In this embodiment, the heat insulating plate is provided on the upper and lower surfaces of the cylinder 38. However, the present invention is not limited to this. Only the space between the upper cylinder 38 and the intermediate partition plate 36 or the upper cylinder 38 and the upper support member 54 are provided. A heat insulating plate may be provided only between the two.
[0054]
In addition, in the case where a heat insulating plate is provided between the lower cylinder 40 and the intermediate partition plate 36 in addition to the above, heat from the lower cylinder 40 is more difficult to be transmitted to the upper cylinder 38. When a heat insulating plate is provided between the lower cylinder and the lower support member 56, the lower cylinder 40 is heated by the intermediate-pressure refrigerant in the discharge muffling chamber 64 formed in the lower support member 56 and the sealed container 12. Therefore, the compression efficiency of the first rotary compression element 32 can be improved.
[0055]
Further, in the present embodiment, the heat insulating plates 140 and 141 are provided in order to make it difficult to transmit heat to the upper cylinder. However, without providing the heat insulating plate, the upper cylinder 38 and the upper support member 54 are formed of a different material such as metal, For example, one may be formed of a spring steel material and the other may be formed of a stainless steel material. In this case, since the upper cylinder 38 and the upper support member 54 are formed of different metals even if they are the same iron-based metal, heat conduction between the upper cylinder 38 and the upper support member 54 decreases, It becomes difficult for heat from the support member 54 to be transmitted to the upper cylinder 38.
[0056]
Further, in the present embodiment, a vertical internal intermediate pressure type multi-stage (two-stage) compression type rotary compressor is used. However, the present invention is not limited to this, and a horizontal rotary compressor or a rotary compression element may be rotated in three stages, four stages or more. It may be applied to a multi-stage compression type rotary compressor having a compression element.
[0057]
【The invention's effect】
As described in detail above, according to the first aspect of the present invention, the first and second cylinders for constituting the first and second rotary compression elements, respectively, and the respective rotary compression elements interposed between the cylinders are provided. An intermediate partition plate for partitioning, and first and second support members each closing an opening surface of the first and second cylinders and having a bearing for a rotating shaft of a driving element, wherein the first cylinder and / or Since a heat-insulating plate is interposed between the second cylinder and the intermediate partition plate and / or the support member, a heat-insulating plate is provided between the first cylinder and the intermediate partition plate. In this case, the inconvenience of heating the second cylinder by the heat of the intermediate-pressure refrigerant gas compressed by the first cylinder can be prevented.
[0058]
Similarly, when a plate having heat insulating property is interposed between the second cylinder and the intermediate partition plate, the plate is compressed by the first rotary compression element or the first cylinder of the first rotary compression element. The disadvantage that the second cylinder is heated by the heat of the intermediate-pressure refrigerant gas can be prevented.
[0059]
Further, when a plate having heat insulating property is interposed between the second cylinder and the second support member, the second cylinder is discharged to a discharge muffling chamber formed in the second support member. The disadvantage of being heated by the cooled refrigerant or the refrigerant in the closed container can be prevented.
[0060]
As a result, the second cylinder is less likely to be heated, and the intermediate-pressure refrigerant gas sucked into the second cylinder can be compressed without being heated, thereby improving the compression efficiency of the second rotary compression element. Can be achieved.
[0061]
On the other hand, when a plate having heat insulation is interposed between the first cylinder and the first support member, the first cylinder is discharged to the discharge muffling chamber formed in the first support member. The disadvantage of being heated by the cooled refrigerant or the refrigerant in the closed container can be prevented.
[0062]
This makes it difficult for the first cylinder to be heated, so that the low-pressure refrigerant sucked into the first cylinder can be compressed without being heated, thereby improving the compression efficiency of the first rotary compression element. Will be able to
[0063]
In general, the performance and reliability of the compressor can be improved.
[0064]
According to the second aspect of the present invention, in addition to the above-mentioned invention, since a gap is formed between the second support member and the plate, the heat of the second support member is less likely to be transmitted to the plate.
[0065]
This makes it more difficult for the second cylinder to be heated, so that the compression efficiency of the second rotary compression element can be improved.
[0066]
According to the invention of claim 3, the first and second cylinders for constituting the first and second rotary compression elements, respectively, and the intermediate partition plate interposed between these cylinders to partition each rotary compression element. And a first and a second support member that respectively close the opening surfaces of the first and second cylinders and have bearings for the rotating shaft of the drive element, and that at least the second cylinder and the second support member are different from each other. Since it is made of a metal material, heat conduction between the second cylinder and the second support member can be suppressed.
[0067]
This makes it difficult for the second cylinder to be heated by the refrigerant discharged into the discharge muffling chamber formed in the second support member or the refrigerant in the closed container, and the intermediate-pressure refrigerant sucked into the second cylinder. Since the gas can be compressed without being heated, the compression efficiency of the second rotary compression element can be improved.
[0068]
As described in claim 4, when carbon dioxide is used as the refrigerant, the effects in the above inventions can be further expected, and the invention can contribute to environmental problems.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a multi-stage compression compressor according to an embodiment of the present invention.
FIG. 2 is an enlarged view of a rotary compression mechanism of the compressor of FIG.
FIG. 3 is a plan sectional view of the compressor of FIG. 1;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Compressor 12 Closed container 12A Container main body 12B End cap 13A Expansion part 13B Thick part 32 First rotary compression element 34 Second rotary compression element 36 Intermediate partition plate 38 Upper cylinder 40 Lower cylinder 54 Upper support member 56 Lower support member 66 Upper cover 68 Lower cover 92 Refrigerant introduction part 92A Refrigerant introduction passages 93A, 93B Communication pipe 94 Refrigerant introduction part 96 Refrigerant discharge part 131 Refueling groove 133 Communication hole 134 Communication hole 140, 141 Insulation plate

Claims (4)

Multistage compression in which first and second rotary compression elements driven by a drive element are provided in a closed container, and refrigerant compressed by the first rotary compression element is sucked into the second rotary compression element and compressed. Type rotary compressor,
First and second cylinders for configuring the first and second rotary compression elements, respectively;
An intermediate partition plate interposed between these cylinders to partition the rotary compression elements,
First and second support members that respectively close the opening surfaces of the first and second cylinders and have bearings for the rotation shaft of the drive element,
A multi-stage compression type wherein a plate having heat insulation properties is interposed between the first cylinder and / or the second cylinder and the intermediate partition plate and / or the support member. Rotary compressor. 2. A multi-stage compression type rotary compressor according to claim 1, wherein a gap is formed between said second support member and said plate. Multistage compression in which first and second rotary compression elements driven by a drive element are provided in a closed container, and refrigerant compressed by the first rotary compression element is sucked into the second rotary compression element and compressed. Type rotary compressor,
First and second cylinders for configuring the first and second rotary compression elements, respectively;
An intermediate partition plate interposed between these cylinders to partition the rotary compression elements,
First and second support members that respectively close the opening surfaces of the first and second cylinders and have bearings for the rotation shaft of the drive element,
A multi-stage rotary compressor, wherein at least the second cylinder and the second support member are made of different metal materials. 4. The multi-stage compression type rotary compressor according to claim 1, wherein carbon dioxide is used as a refrigerant.

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