JP2000110765A - Cooling apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lubricate a roller inner space even if the rotary compressor has a low internal pressure or an intermediate internal pressure. SOLUTION: This cooling apparatus comprises a rotary compressor 1 which contains in a sealed container 2 a rotary compressing element 5 comprised of cylinders 14, 15 with openings at both ends closed, and rollers 18, 19 rotating within the cylinders 14, 15, and which discharges an introduced refrigerant after compressing it in the rotary compressing element 5. The cooling apparatus has an oil separator 60 connected through refrigerant pipes 33, 61 to outlet portions 30, 31 for discharging the refrigerant; a roller inner space 37 partitioned by a rotation shaft 4 for rotating the rollers 18, 19 and inner surfaces of the rollers 18, 19; and an oil introducing portion 48 for introducing oil A from the oil separator 60 into the roller inner space 47, wherein carbon dioxide is used as the refrigerant, and the sealed container 2 has a low internal pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a rotary compressor using natural refrigerant, particularly carbon dioxide (CO ₂ ).

[0002]

2. Description of the Related Art Freon (R11, R12, R134a, etc.) has been generally used as a refrigerant in a refrigeration cycle. However, if CFCs are released into the atmosphere, they have problems such as a large warming effect and ozone layer depletion.

For this reason, in recent years, other natural refrigerants having little effect on the environment, such as oxygen (O) and carbon dioxide (C
O ₂ ), hydrocarbon (HC), ammonia (N
Research using H ₃ ) and water (H ₂ O) as refrigerants has been conducted.

[0004] Of these natural refrigerants, oxygen and water cannot be used as refrigerants in a refrigeration cycle because of their low pressure even when used in rotary compressors. In addition, since ammonia and hydrocarbons are flammable, there is a problem that handling is difficult.

Therefore, development of a compressor using CO _2, ie, carbon dioxide, has been desired.

Conventionally, compressors of reciprocating type and rotary type (rotary type) are roughly classified. However, reciprocating type compressors have problems of noise and vibration.

Therefore, development of a rotary compressor using carbon dioxide has been desired.

[0008] Such a compressor using carbon dioxide,
JP-A-10-19401 (F25B 9/06)
Is disclosed.

[0009]

When carbon dioxide is used as the refrigerant, the pressure of the carbon dioxide refrigerant is about 30 kg / cm ² G at low pressure and about 150 kg at high pressure.
/ Cm ² G, there is a problem in strength unless the inside of the closed vessel of the rotary compressor is set to an internal low pressure or an internal intermediate pressure.

However, in the case of a rotary compressor having a low internal pressure or an internal intermediate pressure using a carbon dioxide refrigerant, the internal pressure of the compression chamber is higher than the internal pressure of the closed vessel. However, it is difficult to supply the oil to the inner space of the roller.

The present invention has been made in view of such problems, and has as its object to supply oil to the inner space of the roller even in a rotary compressor having an internal low pressure or an internal intermediate pressure.

[0012]

In order to achieve the above object, according to the first aspect of the present invention, a rotary compression element comprising a cylinder having both ends closed and a roller rotating in the cylinder is provided in a sealed container. In a cooling device provided with a rotary compressor that compresses and sucks the sucked refrigerant by the rotary compression element and discharges the oil, an oil separator connected through an outlet and a refrigerant pipe that discharges the refrigerant, A roller inner space defined by a rotation shaft and a roller inner surface for rotating the roller, and an oil introduction unit for introducing oil from the oil separator into the roller inner space, using carbon dioxide as a refrigerant, Provided is a cooling device provided with a rotary compressor, wherein the inside of an airtight container is set to a low internal pressure.

For this reason, the carbon dioxide refrigerant and the oil compressed by the roller are separated by the oil separator and supplied to the space inside the roller through the oil introduction part. At this time, since the pressure inside the oil separator is equal to or higher than the intermediate pressure, the oil can be surely supplied to the space inside the roller.

According to a second aspect of the present invention, there is provided a rotary compressor including a plurality of the rotary compression elements and performing a multi-stage compression, wherein the oil separator includes a discharge side refrigerant of one of the rotary compression elements. A cooling device according to claim 1 provided in a pipe.

For this reason, the inside of the oil separator is at an intermediate pressure, and even if it is a rotary compressor with an internal low pressure or an internal intermediate pressure, oil can be supplied to the space inside the roller.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a two-cylinder rotary compressor, FIG. 2 is an enlarged view of a rotary compression element of the rotary compressor, and FIG.
Is a refrigerant circuit diagram using a two-cylinder rotary compressor having the present invention, and FIG. 4 is a refrigerant circuit diagram using a rotary compressor of another embodiment having the present invention.

1 is a two-cylinder rotary compressor (rotary compressor) equipped with the present invention.
An electric element 3 provided at an upper portion in a closed container 2 made of metal such as iron, and a rotary compression element 5 provided below the electric element 3 and driven to rotate by a rotation shaft 4 of the electric element 3. It becomes.

The lower part of the sealed container 2 is an oil reservoir 2.
C, and comprises a container 2A that houses the electric element 3 and the rotary compression element 5, and a sealing lid 2B that seals the container 2A, and supplies power to the electric element 3 to the sealing lid 2B. Terminal terminals for wiring (wiring omitted) 6
Is attached.

The electric element 3 is composed of a rotor 7 and a stator 8, and the rotor 7 is provided with a permanent magnet (not shown) inside a laminated body 10 composed of laminated electromagnetic steel sheets. The windings 11 are attached to a laminated body 12 in which a plurality of electromagnetic steel sheets are laminated.
In addition, 9 is a balancer. Although this structure is referred to as a DC motor, a motor referred to as an AC motor in which an aluminum core made of aluminum is inserted into a laminated electromagnetic steel plate may be used.

Further, when used for an air conditioner of an automobile or the like, an engine of the automobile or the like may be used as a drive source, or another drive source may be used.

The rotary compression element 5 includes a plate middle (intermediate partitioning plate) 13, upper and lower cylinders 14 and 15 mounted above and below the plate middle 13, and a rotary shaft 4 inside the upper and lower cylinders 14 and 15. Vertical eccentric part 16, 1
Upper and lower rollers 18 and 19 which are rotated by 7; upper and lower vanes 20 and 21 which contact the upper and lower rollers 18 and 19 to partition the inside of the upper and lower cylinders 14 and 15 into a high-pressure chamber and a low-pressure chamber;
The main frame 2 that closes the upper and lower openings of the upper and lower cylinders 14 and 15 and allows the rotation of the rotary shaft 4.
2, and a bearing plate 23.

Further, these are arranged in the order of a main frame 22, an upper cylinder 14, a plate middle 13, a lower cylinder 15, and a bearing plate 23, and are connected by bolts 24.

An oil supply hole 25 for supplying oil A to each sliding portion of the rotary compression element 5 is provided in the rotary shaft 4.
Is provided. Further, the outer peripheral surface of the rotating shaft 4 communicates with the oil supply hole 25 so that the oil A is supplied to the main frame 22,
An oil supply groove 26 leading to a bearing portion of the bearing plate 23 is formed. Further, the upper and lower vanes 20 and 21 are provided with a spring 27 for constantly biasing the upper and lower rollers 18 and 19.

Here, the oil A as the lubricating oil may be an existing oil such as a mineral oil (mineral oil), an alkylbenzene oil, an ether oil or an ester oil.

The upper and lower cylinders 14 and 15 are provided with upper and lower introduction pipes for introducing refrigerant, and upper and lower outlet pipes 30 and 31 for discharging refrigerant, respectively. And these upper and lower introduction pipes and upper and lower outlet pipes 30,
The refrigerant pipes 32, 33, 34 are connected to 31, respectively.

The main frame 22 of the rotary compression element 5 has an intermediate pressure chamber 4 communicating with the upper cylinder 14.
The intermediate pressure chamber 45 is defined by the main frame 22 and an upper plate 46 mounted on the upper portion of the main frame 22.

The upper plate 46 is fitted on a bearing portion of the main frame 22 and is locked by a C-ring 46A. Further, 46B is an O-ring. The intermediate pressure chamber 45 is in communication with the upper outlet pipe 30. A high-pressure chamber 50 communicating with the lower cylinder 15 is formed in the bearing plate 23 of the rotary compression element 5.
Is defined by a bearing plate 23 and a lower plate 51 attached to a lower portion of the bearing plate 23. The high-pressure chamber 50 communicates with the lower outlet pipe 31 of the lower cylinder 15.

The lower plate 51 is fitted on the bearing portion of the bearing plate 23 and is locked by a C-ring 51A. Further, 51B is an O-ring.

Reference numeral 53 denotes a valve for releasing pressure to the high pressure chamber 50, that is, to the lower outlet pipe 31 of the lower cylinder 15 when the pressure in the intermediate pressure chamber 45 exceeds a predetermined pressure. A pedestal 36 for supporting the container 2 is a suction muffler.

Next, an embodiment of the refrigerant circuit of the two-cylinder rotary compressor 1 will be described with reference to FIG. The rotary compressor 1 of the present embodiment is a rotary compressor 1 having an internal low pressure or an internal intermediate pressure because carbon dioxide is used as a refrigerant.

In the case of the two-cylinder rotary compressor 1,
A lower outlet pipe 31 provided in the lower cylinder 15 of the rotary compressor 1 and an oil separator 60 are connected via a discharge-side refrigerant pipe 32. Further, the oil separator 6
The condenser 37 and the condenser 37 are connected to each other, and the condenser 37 and the cooler (evaporator) 38 are connected to each other through a refrigerant pipe 40 via an expansion valve 39. The cooler 38 and the upper introduction pipe of the upper cylinder 14 of the rotary compressor 1 are connected by a suction-side refrigerant pipe 33.

Further, the vertical eccentric portions 16, 1 of the rotary shaft 4 are provided.
7, the inner surfaces of the upper and lower rollers 18, 19, the main frame 2
2. The roller inner space 47 defined by the bearing plate 23 and the oil separator 60 communicate with each other via an oil introduction pipe 48. Further, the oil introduction pipe 48 is provided with an introduction valve 49.

The upper cylinder 1 of the rotary compressor 1
The upper outlet pipe 30 and the lower inlet pipe of the lower cylinder 15 provided in 4 are connected by a connecting refrigerant pipe 34.

Accordingly, the gas refrigerant of carbon dioxide, which has been compressed by the two-cylinder rotary compressor 1 and has become high temperature, flows into the oil separator 60, where oil A and carbon dioxide refrigerant are separated in the oil separator 60. You. Thereafter, the carbon dioxide gas refrigerant is cooled by the condenser 37 and the expansion valve 39
, And flows into the cooler 38. Here, the collected gas refrigerant returns to the rotary compressor 1 from the suction-side refrigerant pipe 33 again.

The oil A separated by the oil separator 60 is introduced into the roller inner space 47 of the rotary compression element 5 through the oil introduction pipe 48. At this time,
Since the pressure inside the oil separator 60 is high,
Rotary compressor 1 in which closed vessel 2 has low internal pressure or internal intermediate pressure
Even in this case, it is possible to reliably supply the oil A.

Further, if the oil A is continuously supplied to the roller inner space 47 at high pressure, the roller inner space 47 becomes high pressure and leaks, so that the inside of the sealed container 2 becomes high pressure. Thus, when it is necessary to adjust the amount of oil A introduced, the amount of oil A introduced is adjusted by the introduction valve 49,
A high pressure in the closed container 2 is prevented.

Next, another embodiment of the refrigerant circuit of the above-described two-cylinder rotary compressor 1 will be described with reference to FIG.

In the case of this two-cylinder rotary compressor 1,
The upper outlet pipe 30 provided in the upper cylinder 14 of the rotary compressor 1 and the oil separator 60 are connected to the discharge side connection refrigerant pipe 6.
1 are connected. Further, the oil separator 60 and the lower introduction pipe of the lower cylinder 15 are connected via a suction side connection refrigerant pipe 62.

The lower outlet pipe 31 and the condenser 37 are connected via a discharge side refrigerant pipe 32.
7 and the cooler 38 are connected to a refrigerant pipe 40 through an expansion valve 39.
Connected at The cooler 38 and the upper introduction pipe of the upper cylinder 14 of the rotary compressor 1 are connected by a suction-side refrigerant pipe 33.

The vertical eccentric portions 16, 1 of the rotary shaft 4 are also provided.
7, the inner surfaces of the upper and lower rollers 18, 19, the main frame 2
2. The roller inner space 47 defined by the bearing plate 23 and the oil separator 60 communicate with each other via an oil introduction pipe 48.

Accordingly, the gas refrigerant of carbon dioxide, which has been compressed by the upper cylinder 14 of the two-cylinder rotary compressor 1 and has become high temperature and intermediate pressure, flows into the oil separator 60 and the oil A The carbon dioxide refrigerant is separated. Thereafter, the carbon dioxide gas refrigerant is introduced into the lower cylinder 15 through the suction side connection refrigerant pipe 62 and the lower introduction pipe, and is further compressed. High temperature in lower cylinder 15,
The high-pressure carbon dioxide gas refrigerant is cooled by the condenser 37, expanded by the expansion valve 39, and flows into the cooler 38. Here, the collected gas refrigerant returns to the rotary compressor 1 from the suction-side refrigerant pipe 33 again.

The oil A separated by the oil separator 60 is introduced into the roller inner space 47 of the rotary compression element 5 through the oil introduction pipe 48. At this time,
Since the inside of the oil separator 60 has an intermediate pressure, the oil A can be reliably supplied even if the sealed container 2 is the rotary compressor 1 having an internal low pressure or an internal intermediate pressure.

The rotary compressor 1 having a low internal pressure in the above description is defined as (pressure in the closed vessel 2) <(average pressure in the compression space of the upper cylinder 14) <(average pressure in the compression space of the lower cylinder 15). (The average pressure), the rotary compressor 1 having a pressure relationship of (the average pressure of the compression space of the upper cylinder 14) <(the pressure in the closed vessel 2) < (The average pressure of the compression space of the lower cylinder 15).

The rotary compressor 1 described in detail above includes a home air conditioner, a commercial air conditioner (package air conditioner), a car air conditioner, a home refrigerator, a commercial refrigerator, a commercial freezer, a commercial refrigerator, Case,
It is used for vending machines, water heaters and the like.

Further, the rotary compressor 1 has an output of one horsepower.

[0047]

As described above in detail, according to the present invention, the carbon dioxide refrigerant and the oil compressed by the roller are separated by the oil separator and supplied to the inner space of the roller through the oil inlet. At this time, the inside of the oil separator
Since the pressure is equal to or higher than the intermediate pressure, the oil can be reliably supplied to the roller inner space.

Therefore, the reliability of the rotary compressor can be improved.

According to the second aspect of the present invention, the inside of the oil separator is at an intermediate pressure, so that even in the case of a rotary compressor having an internal low pressure or an internal intermediate pressure, oil can be supplied to the inner space of the roller.

Therefore, the reliability of the rotary compressor can be improved.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view of a two-cylinder rotary compressor.

FIG. 2 is an enlarged view of a rotary compression element of the rotary compressor.

FIG. 3 is a refrigerant circuit diagram using a two-cylinder rotary compressor equipped with the present invention.

FIG. 4 is a refrigerant circuit diagram using a rotary compressor of another embodiment equipped with the present invention.

[Description of Signs] A Oil 1 2-cylinder rotary compressor 2 hermetic container 4 rotary shaft 5 rotary compression element 14 upper cylinder 15 lower cylinder 18 upper roller 19 lower roller 30 upper outlet pipe 31 lower outlet pipe 33 suction side refrigerant pipe 34 Connecting Refrigerant Pipe 45 Intermediate Pressure Chamber 47 Roller Inside Space 48 Oil Introducing Pipe 49 Introducing Valve 60 Oil Separator 61 Discharge Side Connecting Refrigerant Pipe 62 Suction Side Connecting Refrigerant Pipe

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Masaya Tadano 2-5-5 Keihanhondori, Moriguchi-shi, Osaka F-term in Sanyo Electric Co., Ltd. 3H029 AA04 AA09 AA13 AA21 AB03 AB08 BB06 CC04 CC23 CC26 CC33

Claims (2)

[Claims] A rotary compression element comprising a cylinder having both ends closed and a roller rotating in the cylinder is housed in a closed container, and the sucked refrigerant is compressed and discharged by the rotary compression element. In a cooling device provided with a type compressor, an oil separator connected to an outlet for discharging a refrigerant and a refrigerant pipe, a roller inner space defined by a rotating shaft for rotating the roller and a roller inner surface, A cooling unit having an oil introduction unit for introducing oil from the oil separator into a roller inner space, and using carbon dioxide as a refrigerant. 2. A method comprising: a plurality of rotary compression elements;
2. The cooling device according to claim 1, wherein the rotary separator is a rotary compressor that performs multi-stage compression, wherein the oil separator is provided in one of the discharge-side refrigerant pipes of the rotary compression element. 3.