JP4059652B2 - Hermetic rotary compressor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a hermetic rotary compressor having two cylinders. Specifically, the first and second rollers fitted in the two eccentric portions formed on the rotating shaft fitted to the rotor of the electric element and shifted in phase by 180 ° are respectively disposed in the first and second cylinders. The present invention relates to a hermetic rotary compressor that rotates eccentrically and compresses a refrigerant.
[0002]
[Prior art]
The first and second rollers fitted to two eccentric portions formed on the rotating shaft fitted to the rotor of the electric element and shifted in phase by 180 ° are eccentrically rotated in the first and second cylinders, respectively. Japanese Patent Laid-Open No. 5-187374 discloses a hermetic rotary compressor that compresses the above. In such a hermetic rotary compressor having two cylinders, the compression unit in which the roller and the cylinder are combined generates heat and becomes high temperature in the refrigerant compression process. A so-called liquid injection method is adopted in which liquid refrigerant is introduced into a cylinder from a refrigeration apparatus connected to the cylinder.
[0003]
In this case, in Japanese Patent Application Laid-Open No. 5-187374, when liquid injection is performed on the upper and lower cylinders A and B, a method of introducing liquid refrigerant through the respective pipes to the respective cylinders A and B can be considered. Therefore, as a simple configuration instead of this method, as shown in FIG. 3, a single liquid injection passage S is formed in the intermediate partition plate C that partitions the cylinders A and B. A method can be employed in which liquid refrigerant is introduced by connecting the liquid refrigerant introduction pipe P, and liquid refrigerant is introduced into the cylinders A and B from the liquid injection passage.
[0004]
[Problems to be solved by the invention]
As described above, in the system in which one liquid injection passage S is formed in the intermediate partition plate C, and the liquid refrigerant introduction pipe P is connected to this to introduce the liquid refrigerant, the formation of the liquid injection passage S, the liquid refrigerant, In order to ensure the connection of the introduction pipe P and to maintain the strength enough to withstand the pressure during compression, the thickness of the intermediate partition plate is increased. The height of the hermetic rotary compressor is increased.
[0005]
When a hermetic rotary compressor is used in a refrigerator, freezer, or other storage for cooling purposes, or for other cooling equipment, the size of the machine room in which the hermetic rotary compressor is installed is 1 mm. However, it is preferable that 2 mm is as small as possible. For example, in the cooling storage, a hermetic rotary compressor is installed in a machine room formed at the bottom thereof. In this case, since the internal volume of the cooling storage is narrowed by the machine room, the size of the machine room is preferably as small as possible. However, increasing the height of the hermetic rotary compressor requires the height of the machine room for housing it, which is not preferable in terms of securing the internal volume of the cooling storage. Further, in a refrigeration apparatus including a hermetic rotary compressor, the high-temperature refrigerant circuit including the hermetic rotary compressor and the refrigerant condenser and the low-temperature refrigerant circuit including the refrigerant evaporator are separated from each other as the refrigerant. Even in a cooling device connected by a pipe, it is not preferable that the height of the hermetic rotary compressor is increased if the casing surrounding the high-temperature refrigerant circuit is downsized.
[0006]
In view of the above problems, the present invention employs a method in which the thickness of the compression portion does not increase when the liquid injection method is employed as cooling of the hermetic rotary compressor.
[0007]
In order to solve the above-mentioned problems, the present invention provides a sealed container, and an electric element and a compression element driven by the electric element are housed in the hermetic container, and the rotation is fitted to the rotor of the electric element. The shaft has two eccentric portions whose phases are shifted by 180 °, and is rotatably held by the bearings. The compression elements are fitted into the two eccentric portions, respectively, and are respectively in the first and second cylinders. In a hermetic rotary compressor having first and second compression portions including first and second rollers for eccentrically rotating and compressing a refrigerant, the bearing is a first located on the electric element side of the compression element. A liquid injection passage configured to form a bearing and a second bearing located on the opposite side of the bearing and to introduce a liquid refrigerant of a refrigeration apparatus connected to the hermetic rotary compressor is formed in the second bearing, and the liquid injection There is provided a sealed type rotary compressor, characterized in that the road to the second bearing side of the compression to which the compression section of the cylinder to introduce the liquid refrigerant.
[0008]
Thereby, the refrigerant gas discharged from the cylinder of the compression part on the second bearing side cooled by the introduced liquid refrigerant is cooled. And since it is not necessary to thicken a partition plate, size reduction of a hermetic rotary compressor can be achieved. In addition, the heat of the cylinder of the compression unit where the liquid refrigerant is not introduced moves to the cylinder of the compression unit on the second bearing side cooled by the introduced liquid refrigerant, thereby cooling the compression unit where the liquid refrigerant is not introduced. The
[0009]
The compression element is divided into a first compression part on the electric element side and a second compression part located on the opposite side by a thermally conductive partition plate, and passes through the liquid injection passage. The introduced liquid refrigerant is introduced only into the cylinder of the second compression part of the first and second compression parts, and the refrigerant compressed by the second compression part is compressed by the first compression part. After the introduced refrigerant is introduced into the introduced muffler, it is discharged into the space between the compression element and the electric element.
[0010]
Thereby, the refrigerant gas discharged from the cylinder of the second compression unit is cooled, and the high-temperature refrigerant gas discharged from the first compression unit in the muffler into which the refrigerant compressed by the first compression unit is introduced. In order to lower the temperature, the refrigerant gas discharged from the muffler becomes a slightly cooled refrigerant gas and cools the inside of the compressor. Since the partition plate does not need to be thick, the hermetic rotary compressor can be reduced in size, and the heat of the first compression unit moves to the cylinder of the second compression unit via the partition plate, and the first The compression part can be cooled, and the temperature of the refrigerant gas discharged from the compression part can be suppressed.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of the present invention will be described. Each figure shows an embodiment of the present invention, FIG. 1 is an explanatory view showing the internal structure of the hermetic rotary compressor according to the present invention in cross section, and FIG. 2 is applied to the hermetic rotary compressor according to the present invention. It is an embodiment figure of the refrigeration equipment of a liquid injection system.
[0012]
The hermetic rotary compressor of the present invention will be described with reference to the drawings. FIG. 1 shows a vertical hermetic rotary compressor. Reference numeral 1 denotes a hermetic rotary compressor, in which a hermetic container 30, an electric element 2 and a compression element 3 driven by the electric element 2 are accommodated in the hermetic container 30, and are fitted to the rotor 5 of the electric element 2. The attached rotating shaft 6 has two eccentric portions 11 and 12 that are 180 ° out of phase and is rotatably held by a bearing, and the compression element 3 is fitted to the two eccentric portions 11 and 12, respectively. Each of the first and second cylinders 9 and 10 includes first and second compression portions 3A and 3B including first and second rollers 13 and 14 that compress the refrigerant eccentrically. And the said bearing comprises the 1st bearing 15 located in the electric element 2 side of the compression element 3, and the 2nd bearing 16 located in the other side, and the refrigeration apparatus 40 to which the hermetic rotary compressor 1 was connected. A liquid injection passage 31 for introducing the liquid refrigerant is formed in the second bearing 16, and the liquid refrigerant is introduced from the liquid injection passage 31 into the Linder 10 of the second compression section 3 </ b> B on the second bearing 16 side.
[0013]
More specifically, the compression element 3 is divided into a first compression part 3A on the electric element 2 side and the second compression part 3B located on the opposite side by a thermally conductive partition plate 8. The liquid refrigerant introduced through the liquid injection passage 31 is introduced only into the cylinder 10 of the second compression unit 3B of the first compression unit 3A and the second compression unit 3B. In addition, the refrigerant compressed by the second compression unit 3B is introduced through the bypass pipe 21 into the muffler 19 into which the refrigerant compressed by the first compression unit 3A is introduced, and then between the compression element 3 and the electric element 2 A refrigerant gas discharge hole is formed in the wall of the muffler 19 so as to be discharged into the space.
[0014]
The sealed container 30 is a container in which the electric element 2 and the compression element 3 are accommodated in a previously divided part, and the joint between the two is sealed by high-frequency welding or the like. The electric element 2 includes a stator 4 fixed to the inner wall of the hermetic container 30 by a shrinking method or the like, and a rotating shaft rotatably supported by a first bearing 15 and a second bearing 16 inside the stator 4. 6 and a rotor 5 with 6 as a center. The rotor 5 has a configuration in which a permanent magnet is embedded. The stator 4 includes a stator winding 7 that applies a rotating magnetic field to the rotor 5. Between the stator 4 and the hermetic container 30, a plurality of oil return passages 32 penetrating in the vertical direction are arranged around the stator 4 at substantially equal angles. The oil return passage 32 is formed by cutting the outer shape of the stator 4. Reference numeral 33 denotes an air gap formed between the stator 4 and the rotor 5.
[0015]
The compression element 3 includes a first rotary cylinder 9 and a second rotary cylinder 10 that are partitioned by a thermally conductive partition plate 8. The peripheral surfaces of the cylinders 9 and 10 are fixed to the inner wall of the sealed container 30 by a method such as shrinking or the like. The cylinders 9 and 10 correspond to eccentric portions 11 and 12 that are rotationally driven by the rotary shaft 6, and the eccentric portions 11 and 12 have a configuration in which the eccentric positions are shifted from each other by 180 °.
[0016]
Reference numerals 13 and 14 denote a first roller and a second roller that rotate in the cylinders 9 and 10, respectively, and rotate in the cylinder by the rotation of the eccentric portions 11 and 12, respectively. Reference numerals 15 and 16 denote a first bearing and a second bearing, respectively. The first bearing 15 forms a compression space in which the cylinder 9 is closed with the partition plate 8. Further, the second bearing 16 forms a compression space in which the cylinder 10 is closed with the partition plate 8. The first bearing 15 and the second bearing 16 are coupled to the upper and lower surfaces of the compression element 3 with bolts for coupling the compression element 3, and bearing surfaces 17 and 18 that respectively rotatably support the lower part of the rotating shaft 6. It has.
[0017]
Reference numerals 19 and 20 denote discharge mufflers, which are attached with bolts for coupling the compression element 3 so as to cover the first bearing 15 and the second bearing 16, respectively. The cylinder 9 and the discharge muffler 19 communicate with each other through a refrigerant gas discharge hole (not shown) formed in the first bearing 15. The cylinder 10 and the discharge muffler 20 communicate with each other through a refrigerant gas discharge hole (not shown) formed in the second bearing 16. A bypass pipe 21 guides the refrigerant gas of the discharge muffler 20 to the discharge muffler 19.
[0018]
Reference numeral 22 denotes a refrigerant gas discharge pipe provided on the upper wall of the sealed container 30. Reference numerals 23 and 24 denote refrigerant suction pipes connected to the cylinders 9 and 10, respectively. Reference numeral 25 denotes a sealed terminal, which supplies power supplied from the outside of the sealed container 30 to the stator winding 7 of the stator 4 through a lead wire (not shown).
[0019]
Next, the refrigeration apparatus 40 will be described with reference to FIG. 41 is a condenser, 42 is a liquid receiver, 43 is an expansion valve as a pressure reducing device, 44 is an evaporator, and 45 is an accumulator. The hermetic rotary compressor 1, the condenser 41, the liquid receiver 42, the expansion valve 43, the evaporator 44, and the accumulator 45 are sequentially connected in an annular manner through a refrigerant pipe to constitute a refrigeration cycle. A temperature sensing tube 46 is attached to the outlet pipe of the evaporator 44 and communicates with the expansion valve 43 through a capillary tube 47.
[0020]
From a pipe 48 between the outlet side of the liquid receiver 42 and the expansion valve 43, a liquid injection pipe 49 connected to a liquid injection passage 31 formed laterally in the second bearing 16 of the hermetic rotary compressor 1. Is provided. In the middle of the liquid injection pipe 49, the injection control valve 50 that adjusts the injection amount of the liquid refrigerant based on the discharge gas temperature of the hermetic rotary compressor 1 and the primary side (inflow side) of the injection control valve 50 are opened and closed. A solenoid valve 51 as a valve is provided. The injection control valve 50 is a so-called expansion valve, and its temperature sensing cylinder 52 is communicated with the injection control valve 50 via the capillary tube 53, and the temperature sensing cylinder 52 is connected to the discharge side pipe 54 of the hermetic rotary compressor 1. It is attached.
[0021]
The injection control valve 50 increases the inflow amount (injection amount) of liquid refrigerant into the hermetic rotary compressor 1 when the discharge gas temperature of the hermetic rotary compressor 1 rises and the temperature of the discharge side pipe 54 becomes high. In addition, when the temperature of the discharge side pipe 54 becomes low, control is performed so as to reduce the amount of liquid refrigerant flowing into the hermetic rotary compressor 1 (injection amount).
[0022]
55 is provided in communication with the suction pipe 23 or 24 to the hermetic rotary compressor 1, detects its low pressure, and when the low pressure rises to a predetermined low pressure cut-in value, A pressure detection device that starts and opens the electromagnetic valve 51 in synchronism with it, stops the hermetic rotary compressor 1 when it drops to a predetermined low-pressure cutout value, and controls to close the electromagnetic valve 51 in synchronism with it. is there.
[0023]
In the above configuration, when the low pressure of the suction pipe 23 or 24 of the hermetic rotary compressor 1 rises to the low pressure cut-in value, the hermetic rotary compressor 1 is started by the pressure detector 55 and the electromagnetic valve 51 is opened. The high-temperature and high-pressure refrigerant gas discharged from the hermetic rotary compressor 1 is condensed and liquefied by the condenser 41, temporarily stored in the liquid receiver 42, and then decompressed by the expansion valve 43 and evaporated by the evaporator 44. The ambient air is cooled by this evaporation, and the refrigeration apparatus 40 exhibits a cooling capacity. The refrigerant that has left the evaporator 44 passes through the accumulator 45 and flows into the cylinders 9 and 10 through the refrigerant suction pipes 23 and 24, respectively, and is compressed. The refrigerant then flows into the condenser 41 from the discharge side pipe 54 again.
[0024]
When the hermetic rotary compressor 1 is started, the temperature of the discharge side pipe 54 rises. Therefore, the temperature sensing cylinder 52 senses the temperature of the pipe, and the opening degree of the injection control valve 50 is increased. A part of the liquid refrigerant is introduced from the liquid injection pipe 49 through the liquid injection passage 31 into the cylinder 10 of the second compression section 3B. The liquid refrigerant flowing into the cylinder 10 evaporates there and takes heat away from the surroundings, so that the cylinder 10 is cooled and the temperature of the discharged gas refrigerant decreases.
[0025]
The evaporation of the refrigerant in the evaporator 44 gradually reduces the ambient air temperature, the temperature of the outlet pipe of the evaporator 44 decreases, and the expansion valve 43 is substantially closed or completely closed, whereby pump down is started. When the low pressure of the suction pipe 23 or 24 of the hermetic rotary compressor 1 is reduced to the low pressure cutout value, the pressure detection device 55 stops the hermetic rotary compressor 1 and the electromagnetic valve 51 is closed. Then, when the low pressure of the suction pipe 23 or 24 of the hermetic rotary compressor 1 rises again to the low pressure cut-in value, the hermetic rotary compressor 1 is started by the pressure detector 55, the electromagnetic valve 51 is opened, and The same operation is performed.
[0026]
Since the temperature of the discharge side pipe 54 gradually decreases due to the stop of the hermetic rotary compressor 1, the temperature sensing cylinder 52 senses the temperature of this pipe and decreases the valve opening of the injection control valve 50. However, since the solenoid valve 51 is closed, the inflow of the liquid refrigerant from the liquid receiver 42 to the injection control valve 50 is cut off.
[0027]
As described above, by the operation of the hermetic rotary compressor 1, a part of the liquid refrigerant in the liquid receiver 42 is introduced from the liquid injection pipe 49 into the cylinder 10 of the second compression unit 3B through the liquid injection passage 31. Then, since it evaporates and takes heat from the surroundings, the cylinder 10 is cooled, and the temperature of the gas refrigerant discharged from the cylinder 10 decreases. The gas refrigerant discharged from the cylinder 10 flows into the discharge muffler 20 and then flows into the discharge muffler 19 through the bypass pipe 21.
[0028]
On the other hand, since the high-temperature gas refrigerant from the cylinder 9 is discharged to the discharge muffler 19, the temperature of the high-temperature gas refrigerant is lowered by the cooled discharge gas refrigerant flowing from the cylinder 10 through the bypass pipe 21. . The gas refrigerant, which has been cooled slightly when the temperature is lowered, is discharged from a discharge hole formed in the discharge muffler 19 into a space between the electric element 2 and the compression element 3, and while cooling the electric element 2, The air rises through an air gap 33 formed between the rotor 5 and flows out to a discharge side pipe 54 communicated with a discharge pipe 22 provided on the upper wall of the hermetic container 30 and circulates as described above. The oil mist discharged from the discharge hole formed in the discharge muffler 19 together with the refrigerant returns from the oil return passage 32 to the oil reservoir at the bottom in the sealed container 30 through the gap between the cylinders 9 and 10 and the sealed container 30. To do. The oil in the oil reservoir is supplied for lubrication of the compression parts 3A and 3B.
[0029]
As described above, the liquid injection passage 31 for introducing the liquid refrigerant of the refrigeration apparatus 40 to which the hermetic rotary compressor 1 is connected is formed in the second bearing 16, and the compression portion on the second bearing 16 side from the liquid injection passage 31. Since the liquid refrigerant is introduced into the 3B Linder 10, it is not necessary to make the partition plate 8 thick, so that the hermetic rotary compressor can be downsized.
[0030]
In addition, the gas refrigerant discharged from the cylinder 10 of the compression unit 3B is cooled, and the heat of the cylinder 9 moves to the cylinder 10 cooled through the partition plate 8, and the temperature of the cylinder 9 decreases. The temperature of the gas refrigerant to be discharged is also indirectly cooled, and the gas refrigerant discharged from the cylinder 9 and the cylinder 10 is totally cooled.
[0031]
In the above, the gas refrigerant discharged from the cylinder 10 flows into the discharge muffler 20 and then flows into the discharge muffler 19 through the bypass pipe 21. As another method, the cylinder 9, the cylinder 10, the partition plate 8, and the bearing are used. A communication hole penetrating through 15 and 16 is formed, and the gas refrigerant discharged from the cylinder 10 flows into the discharge muffler 20 and then flows into the discharge muffler 19 through the communication hole.
[0032]
The gas refrigerant discharged from the cylinder 10 may be configured to mix with the gas refrigerant discharged from the discharge muffler 19 after flowing into the discharge muffler 20 without being introduced into the discharge muffler 19. As one of the means, the gas refrigerant discharged from the cylinder 10 flows into the discharge muffler 20 and then is discharged into the space between the electric element 2 and the compression element 3 through the bypass pipe. The temperature of the gas refrigerant in the space in the sealed container 30 can be lowered by mixing with the gas refrigerant discharged from the airtight container 30.
[0033]
In the above embodiment, the hermetic rotary compressor 1 is a vertical type, but the hermetic rotary compressor 1 can also be applied as a horizontal type. In that case, the refrigerant suction pipes 23, 24, the sealed terminal 25, and the accumulator 45 are arranged at the top of the hermetic rotary compressor 1.
[0034]
The present invention is not limited to the above-described embodiments, and various modifications can be considered without departing from the technical scope of the present invention, and the various embodiments related thereto are included.
[0035]
【The invention's effect】
According to the first aspect of the present invention, the refrigerant gas discharged from the cylinder of the compression portion on the second bearing side cooled by the introduced liquid refrigerant is cooled. And since it is not necessary to thicken a partition plate, size reduction of a hermetic rotary compressor can be achieved. In addition, the heat of the cylinder of the compression unit where the liquid refrigerant is not introduced moves to the cylinder of the compression unit on the second bearing side cooled by the introduced liquid refrigerant, thereby cooling the compression unit where the liquid refrigerant is not introduced. The
[0036]
According to the invention of claim 2, the refrigerant gas discharged from the cylinder of the second compression section is cooled and discharged from the first compression section in the muffler into which the refrigerant compressed by the first compression section is introduced. In order to lower the temperature of the high-temperature refrigerant gas, the refrigerant gas discharged from the muffler becomes a slightly cooled refrigerant gas to cool the inside of the compressor. Since the partition plate does not need to be thick, the hermetic rotary compressor can be reduced in size, and the heat of the first compression unit moves to the cylinder of the second compression unit via the partition plate, and the first The compression part can be cooled, and the temperature of the refrigerant gas discharged from the compression part can be suppressed.
[Brief description of the drawings]
FIG. 1 is an explanatory view showing in cross section the internal structure of a hermetic rotary compressor according to the present invention.
FIG. 2 is a diagram showing an embodiment of a liquid injection type refrigeration apparatus applied to a hermetic rotary compressor according to the present invention.
FIG. 3 is an explanatory view of a hermetic rotary compressor in which a liquid injection passage is formed in a partition plate.
[Explanation of symbols]
1... Hermetic rotary compressor 2... Electric element 3... Compression element 3 A... First compression part 3 B.・ ・ ・ ・ ・ Stator 5 ・ ・ ・ ・ ・ Rotor 6 ・ ・ ・ ・ ・ Rotary shaft 7 ...... Stator winding 8 ・ ・ ・ Partition plate 9 ・ ・ ・.. First cylinder 10 ... Second cylinder 11 ... Eccentric part 12 ... Eccentric part 13 ... First roller 14 ... Second roller 15 ... First Bearing 16 ... Second bearing 19 ... Muffler 20 ... Muffler 21 ... Bypass pipe 22 ... Discharge pipe 23 ... Refrigerant suction pipe 24 ... Refrigerant suction Pipe 30 ... Airtight container 31 ... Liquid injection passage 42 ... Liquid receiver 49 ... Liquid injection pipe 50 ... Injection control 51 ... electromagnetic valve

Claims (2)

An airtight container and an electric element and a compression element driven by the electric element are accommodated in the airtight container, and a rotating shaft fitted to a rotor of the electric element has two eccentricities whose phases are shifted by 180 °. And the compression element is fitted to the two eccentric parts and eccentrically rotates in the first and second cylinders respectively to compress the refrigerant. In a hermetic rotary compressor having a first and a second compression section having two rollers, the bearing includes a first bearing located on the electric element side of the compression element and a second bearing located on the opposite side. A liquid injection passage configured to introduce liquid refrigerant of a refrigeration apparatus to which the hermetic rotary compressor is connected is formed in the second bearing, and the second bearing side is compressed from the liquid injection passage. Hermetic rotary compressor and introducing the liquid refrigerant into the compression section of the cylinder that.   In Claim 1, The said compression element is the structure divided | segmented into the said 2nd compression part located in the said 1st compression part by the side of the said electric element by the heat conductive partition plate, and the other side, The said liquid The liquid refrigerant introduced through the injection passage is introduced only into the cylinder of the second compression section of the first and second compression sections, and the refrigerant compressed by the second compression section is the first compression section. A hermetic rotary compressor, wherein the refrigerant compressed in the section is introduced into a muffler into which the refrigerant is introduced and then discharged into a space between the compression element and the electric element.

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