JP2000104688A - Rotary compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To let sufficient oil be supplied even if the flow speed of gaseous refrigerant is low. SOLUTION: In this rotary compressor, a rotary compression element is housed in a hermetically sealed enclosure wherein the element is formed out of a cylinder the openings at both ends of which are blocked, each roller to be rotated in the inside of the cylinder, and of vanes forming each compression space in the inside of the cylinder by letting each vane abut against the rollers, and concurrently, an oil basin 2C is formed at the bottom part of the hermetically sealed closure so as to allow refrigerant sucked in to be compressed by the rotary compression element for letting compressed medium be discharged out. In this case. the compressor is also provided with introducing pipes 28 29 provided for the cylinder to introduce refrigerant to the rotary compression element, a joint 45 and the like, which connects the introducing pipes 28 and 29 with the refrigerant pipelines 33 and 34, and concurrently, has its tip end parts inserted into the introducing pipes 28 29, and with a communication pipe 55 communicated with the oil basin 2C in a place close to the tip ends of the joint 45 and the like.

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 As a prior art prior to the present invention, Japanese Patent No. 2517346 (F04B49 / 02) discloses:
A closed container having an oil reservoir at the bottom, a motorized element housed in the container, and a plurality of compression elements driven by the motorized element, the compression element is a cylinder,
A rotary shaft rotated by the electric element, a roller rotated along the inner wall of the cylinder by an eccentric portion of the rotary shaft, a vane reciprocatingly sliding in a groove provided in the cylinder in contact with the roller, It consists of a bearing that seals the opening of the cylinder, and separates each compression element with an intermediate partition plate.
In the compressor, the rotary shaft is provided with a first oil supply passage for supplying oil from an oil reservoir to each sliding portion.
The compression element is provided with a second oil supply passage for supplying oil from an oil reservoir into the cylinder, one end of the second oil supply passage is provided in the intermediate partition plate, and the other end of the first oil supply passage is provided with the first oil supply passage. A temperature detection element is provided in a discharge path of the compressor, and a temperature detection element is provided in a discharge path of the compressor, and on / off control of the compressor is performed based on a detection result of the temperature detection element. A control device for a compressor is disclosed.

As a method of supplying oil into a cylinder, there is a method in which a thin tube communicating with an oil reservoir is provided at a refrigerant supply port to the cylinder, and oil in the oil reservoir is sucked up by inflow of a gas refrigerant.

[0004]

In this case, if the flow rate of the gas refrigerant is low, it is difficult to suck up the oil, and there is a problem that the oil is not supplied sufficiently.

[0005] Unless sufficient oil is supplied, there has been a problem that the capacity of the compressor cannot be sufficiently obtained.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and provides a rotary compressor intended to supply a sufficient amount of oil even when the flow rate of a gas refrigerant is low.

[0007]

In order to achieve the above object, according to the first aspect of the present invention, there is provided a cylinder having both ends closed, a roller rotating in the cylinder,
A rotary compression element consisting of a vane forming a compression space in the cylinder by being in contact with the roller is accommodated in a closed container, and an oil reservoir is formed at the bottom of the closed container, and the sucked refrigerant is rotated by the rotation. In a rotary compressor that compresses and discharges by a compression element, an introduction pipe that is provided in the cylinder and that introduces a refrigerant to the rotary compression element, and connects the introduction pipe and the refrigerant pipe, and has a tip inside the introduction pipe. The present invention provides a rotary compressor provided with a joint into which a portion is inserted, and a communication pipe near the distal end of the joint, the communication pipe communicating with the oil reservoir.

For this reason, a step is formed between the inner surface of the introduction pipe and the joint inserted into the introduction pipe, and turbulence occurs in the refrigerant at the step, thereby promoting the introduction of oil from the communication pipe. You can do it.

According to a second aspect of the present invention, there is provided the rotary compressor according to the first aspect, wherein the refrigerant is carbon dioxide.

[0010] Therefore, even when carbon dioxide having a low flow rate is used as the refrigerant, it is possible to supply a sufficient amount of oil.

[0011]

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 equipped with the present invention, FIG. 2 is an enlarged view of a main part of a two-cylinder rotary compressor equipped with the present invention, and FIG. Refrigeration circuit diagram using a two-cylinder rotary compressor provided, FIG. 4
FIG. 2 is a Mollier diagram in a refrigeration circuit diagram using a two-cylinder rotary compressor equipped with 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 may be used as a drive source, or another drive source may be used.

The rotary compression element 5 includes a plate middle (intermediate partition 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
The upper and lower rollers 18 and 19 which are rotated by 7, the upper and lower vanes which contact the upper and lower rollers 18 and 19 and partition the inside of the upper and lower cylinders 14 and 15 into a high pressure chamber and a low pressure chamber, and upper and lower openings of the upper and lower cylinders 14 and 15 It comprises a main frame 22 that closes and allows the rotation of the rotary shaft 4, 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.

The rotary shaft 4 is provided with an oil supply hole 25 for supplying lubricating oil, that is, oil A, to each sliding portion of the rotary compression element 5. Further, an oil supply groove 26 is formed on the outer peripheral surface of the rotating shaft 4 and communicates with the oil supply hole 25 to guide the oil A to the inside of the upper and lower rollers 18 and 19. Furthermore, the upper and lower rollers 18, 1
9 is provided with a spring for constantly biasing it.

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 28 and 29 for introducing the refrigerant, and upper and lower outlet pipes 30 and 31 for discharging the refrigerant, respectively. And these upper and lower introduction pipes 28, 29
Refrigerant pipes 32, 33, 34 are connected to the upper and lower outlet pipes 30, 31 via a suction joint 45 and a discharge joint 46, respectively.

The suction joint 45 has an introduction-side insertion pipe 47 inserted into the upper and lower introduction pipes 28 and 29,
47 are provided, and double rubber packings 48, 48 are provided on the outer periphery of the distal ends of the introduction-side insertion tubes 47, 47. The suction joint 45 is made of iron,
Or, it is formed of stainless steel or the like.

Further, an iron joint base 49 is welded to the mounting position of the suction joint 45 of the closed container 2, and the suction joint 45 is screwed to the joint base 49 with a bolt 50. The joint base 49 has a hole through which the introduction-side insertion pipes 47 of the suction joint 45 are inserted.

Further, the inner circumferences of the open ends of the upper and lower introduction pipes 28 and 29 are inclined so as to facilitate insertion of the introduction side insertion pipes 47 and 47. The distal ends of the insertion tubes 47, 47 also have inclined outer peripheries at their open ends.

The upper part of the upper introduction pipe 28 is located at a position that does not interfere with the tip of the introduction side insertion pipe 47 of the suction joint 45, and communicates in an inverted U-shape near the introduction side insertion pipe 47. A tube 55 is provided.

The communicating pipe 55 communicates with the oil reservoir 2C of the closed vessel 2, and the top of the inverted U is located above the level of the oil A. This is to prevent the oil A from flowing into the upper introduction pipe 28 when the operation of the rotary compressor 1 is stopped, that is, when the supply of the oil A is unnecessary.

As described above, since the introduction side insertion pipe 47 of the suction joint 45 is inserted into the upper introduction pipe 28, a step is formed between the inner surface of the upper introduction pipe 28 and the passage of the refrigerant in the introduction side insertion pipe 47. B is formed. Further, since the outer periphery of the opening end of the introduction-side insertion pipe 47 is inclined, a turbulent flow occurs at the step B and the pressure becomes low, so that the communication pipe 55 can easily guide the oil A from the oil reservoir 2C. Things.

Therefore, since the rotary compressor 1 has an internal low pressure or an internal intermediate pressure using carbon dioxide, the oil A can be sufficiently supplied even if the flow rate of the refrigerant is reduced.

Reference numeral 51 denotes a pressure control tube for preventing the carbon dioxide gas refrigerant from leaking from between the main frame 22 or the bearing plate 23 and the rotary shaft 4 and the like, so that the inside of the closed vessel 2 becomes high pressure. A pedestal 36 for supporting the closed container 2 is a suction muffler.

Next, the discharge joint 46
Are provided with outlet-side insertion pipes 52, 52 inserted into the upper and lower outlet pipes 30, 31, respectively.
Double rubber packings are provided on the outer periphery of the distal end portions of 2, 52. The discharge joint 46 is made of iron, stainless steel, or the like.

At the position where the discharge joint 46 of the closed container 2 is attached, an iron joint base 5 is provided.
3 is welded and the discharge joint 4
6 is screwed to the joint base 53 with a bolt 54. The joint base 53 has a hole through which the outlet side insertion pipes 52 of the discharge joint 46 are inserted.

Further, the inner circumferences of the open ends of the upper and lower outlet pipes 30 and 31 are inclined so as to facilitate the insertion of the outlet side insertion pipes 52 and 52. The distal ends of the insertion tubes 52, 52 also have an inclined outer periphery at the open end.

Next, the refrigerant circuit of the two-cylinder rotary compressor 1 will be described with reference to FIGS.

In the case of this two-cylinder rotary compressor 1,
The discharge side refrigerant pipe 32 and the condenser 37 are connected via a lower outlet pipe 31 provided in the lower cylinder 15 of the rotary compressor 1 and a discharge joint 46, and the condenser 37 and the condenser (evaporator) are connected. ) 38 is connected to 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 to each other by the suction side refrigerant pipe 33 via the suction joint 45.

The refrigerant pipe 40 connecting the condenser 37 and the expansion valve 39 is provided with a bypass pipe 43 connected to a subcooler 42 via a bypass expansion valve 41.

The supercooler refrigerant pipe 44 from the subcooler 42 is connected to an upper outlet pipe 30 provided in the upper cylinder 14 of the rotary compressor 1 and a lower inlet pipe 29 of the lower cylinder 15.
And a connection refrigerant pipe 34 connecting the suction pipe and the suction muffler 36.

The connecting refrigerant pipe 34 is connected to the upper outlet pipe 3.
0 is connected via a discharge joint 46, and the lower introduction pipe 29 is connected via a suction joint 45.

The supercooler 42 has a double pipe structure, in which the refrigerant from the bypass pipe 43 flows inside, and the refrigerant in the refrigerant pipe 40 flows outside. Conversely, the inside may be the refrigerant pipe 40 and the outside may be the bypass pipe 43.

Further, a structure provided in contact with heat conduction may be used.

The refrigerant pipe 40 after branching off from the bypass pipe 43 is introduced into the subcooler 42, where the refrigerant pipe 40 comes into contact with the bypass pipe 43 after the bypass expansion valve 41 in a heat conductive manner. It is provided. Thereafter, it is connected to the expansion valve 39 described above.

Accordingly, the gas refrigerant of carbon dioxide, which has been compressed by the two-cylinder rotary compressor 1 and has become high temperature, is cooled by the condenser 37, and is further cooled by the subcooler 42 to the heat of the bypass pipe 43. After the replacement, that is, the heat is released, the expansion valve 39 expands. Thereafter, the gas refrigerant flowing into the cooler 38 and radiating heat here returns to the rotary compressor 1 again from the suction side refrigerant pipe 33.

A part of the refrigerant condensed in the condenser 37 is diverted to the bypass pipe 43 and is adiabatically expanded by the bypass expansion valve 41.
From the heat. The refrigerant collected in the supercooler 42 is mixed with the high-temperature, high-pressure refrigerant in the upper cylinder 14,
The high-temperature, high-pressure refrigerant is cooled and flows into the lower cylinder 15. In addition, the refrigerant after collecting heat in the supercooler 42 is:
The high temperature after the discharge of the upper cylinder 14 is lower than the high pressure refrigerant.

Here, the critical pressure shown in FIG. 4 is about 72 to 73 kgf / cm ² G in the case of carbon dioxide refrigerant,
Above this critical pressure, that is, in the supercritical region, the carbon dioxide refrigerant is gasified.

In FIG. 4, point A is the refrigerant discharged from the supercooler 42 and the compressor upper cylinder 14 and merged into the lower cylinder 15, and point B is the refrigerant discharged from the lower cylinder 15. is there.

At the point C, the refrigerant that has been condensed in the condenser 37 and then diverted is adiabatically expanded by the bypass expansion valve 41. The point D is adiabatically expanded and pressure-reduced refrigerant that has radiated heat, flows into the supercooler 42, and cools the refrigerant at the point C to the point E.

The supercooled refrigerant at the point E is adiabatically expanded by the expansion valve 39 to be in the state at the point F. Thereafter, as indicated by point G, the refrigerant that has collected heat in the cooler 38 and has become high temperature flows into the upper cylinder 14.

As shown at point H, the refrigerant which has been compressed by the upper cylinder 14 and has become high temperature and high pressure
2, the pressure decreases, the refrigerant is used for supercooling, and merges with the refrigerant whose temperature has risen (however, as described above, the high temperature after discharge of the upper cylinder 14 and the lower temperature than the high-pressure refrigerant). The cooled refrigerant flows into the rotary compressor 1.

The rotary compressor 1 having an internal low 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), an automobile 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 a size of 15 frames and an output of 1 horsepower.

[0051]

As described above in detail, according to the present invention, a step is formed between the inner surface of the introduction pipe and the joint inserted into the introduction pipe, and turbulent flow occurs in the refrigerant at the step. In addition, the introduction of oil from the communication pipe can be promoted.

Therefore, even if the flow rate of the carbon dioxide refrigerant is small, sufficient oil can be supplied, and the performance of the rotary compressor can be ensured.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a two-cylinder rotary compressor equipped with the present invention.

FIG. 2 is an enlarged view of a main part of a two-cylinder rotary compressor equipped with the present invention.

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

FIG. 4 is a Mollier diagram in a refrigeration circuit diagram using a two-cylinder rotary compressor equipped with the present invention.

[Explanation of symbols]

 Reference Signs List A Oil B Step 1 Two-cylinder rotary compressor 2 Closed container 2C Oil reservoir 3 Electric element 5 Rotary compression element 14 Upper cylinder 15 Lower cylinder 18 Upper roller 19 Lower roller 22 Main frame 23 Bearing plate 28 Upper introduction pipe 29 Lower introduction Pipe 33 Suction side refrigerant pipe 34 Connection refrigerant pipe 45 Suction joint 47 Introducing side insertion pipe 50 Communication pipe

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Masaya Tadano 2-5-5 Keihanhondori, Moriguchi-shi, Osaka F-term in Sanyo Electric Co., Ltd. (reference) 3H029 AA04 AA09 AA13 AA21 AB03 AB08 BB06 CC24 CC33

Claims (2)

[Claims] 1. A rotary compression element comprising a cylinder whose both ends are closed, a roller rotating in the cylinder, and a vane forming a compression space in the cylinder by contacting the roller. And a rotary compressor that forms an oil reservoir at the bottom of the sealed container and compresses and sucks the sucked refrigerant by the rotary compression element. The rotary compressor is provided in the cylinder, and the refrigerant is supplied to the rotary compression element. An introduction pipe to be introduced, a joint connecting the introduction pipe and the refrigerant pipe, and a joint into which the tip is inserted into the introduction pipe, and a communication pipe communicating with the oil reservoir near the tip of the joint are provided. A rotary compressor, characterized in that: 2. The rotary compressor according to claim 1, wherein said refrigerant is carbon dioxide.