KR100585808B1 - Multi-stage rotary compressor - Google Patents

Abstract

The present invention relates to a multistage rotary compressor, the multistage rotary compressor of the present invention comprises: a casing having a sealed space therein; A driving unit mounted to the casing to generate a driving force; A first compression unit and a second compression unit receiving a driving force from the drive unit to compress the refrigerant; A first suction pipe guiding the refrigerant to the first compression unit; A first control valve mounted to the first suction pipe to control the suction refrigerant; A second suction pipe for guiding the refrigerant to the second compression unit; A chamber for temporarily storing the refrigerant discharged from the second compression unit by covering a second discharge valve that regulates the discharge refrigerant of the second compression unit; A second control valve installed on the chamber; And a connecting pipe connecting the chamber and the first control valve, such that the refrigerant discharged from the second compression unit is directly sucked into the first compression unit and compressed or discharged once in each compression unit. By selectively guiding the refrigerant, it is possible not only to change the capacity according to the change of the room temperature, but also to save power while using all the plurality of compression units in the saving mode for reducing the discharge amount of the refrigerant. The process was simplified to minimize manufacturing costs.

Rotary compressor, multi-stage, three-way valve, variable capacity, actuator

Description

Multi-stage rotary compressor {MULTI-STAGE ROTARY COMPRESSOR}

1 is a longitudinal sectional view showing a first embodiment of the present invention;

2 is a cross-sectional view showing operation in power mode according to a first embodiment of the present invention;

3 is a cross-sectional view showing the operation in the saving mode according to the first embodiment of the present invention,

4 is a longitudinal sectional view showing a second embodiment of the present invention;

5 is a cross-sectional view showing operation in power mode according to a second embodiment of the present invention;

6 is a cross-sectional view showing operation in a saving mode according to a second embodiment of the present invention;

Fig. 7 is a longitudinal sectional view showing the third embodiment of the present invention.

** Description of symbols for the main parts of the drawing **

100: casing 110: discharge tube

130: accumulator 200: drive unit

210: stator 220: rotor

230: rotating shaft 300: the first compression unit

310: first cylinder 320: upper bearing

330: first internal space 340: first rolling piston

350: intermediate bearing 360: first discharge hole

370: first discharge valve 400: second compression unit

410: second cylinder 430: second internal space

440: second rolling piston 450: lower bearing

460: second discharge hole 470: second discharge valve

500: first control valve 510: fourth control valve

520: third control valve 600: second control valve

610: on-off valve 620: spring

630: first communication hole 640: second communication hole

650: housing 710: first suction pipe

720: connector 730: second suction pipe

740: chamber 800: actuator

An air-conditioner keeps the room in a comfortable state by keeping the room temperature at a set state.

Air conditioners generally comprise a refrigeration cycle system. The refrigeration cycle system includes a compressor for compressing a refrigerant, a condenser for releasing heat to the outside while the refrigerant compressed in the compressor is condensed, an expansion valve for reducing the pressure of the refrigerant condensed in the condenser, and the expansion valve. It is configured to include an evaporator that absorbs external heat as the refrigerant evaporates.

The compressor, condenser, expansion valve and evaporator are connected by a connecting tube to form a cycle.

As the refrigeration cycle system is powered and the compressor is operated, the high temperature and high pressure refrigerant discharged from the compressor is sequentially passed through the condenser, the expansion valve, and the evaporator, and then sucked into the compressor, and the same process is repeated. In the process, heat is generated in the condenser and absorbs external heat from the evaporator to form cold air. The heat generated from the condenser and the cold air formed in the evaporator are selectively circulated and flowed into the room to keep the room in a comfortable state.

Generally, a compressor converts electrical energy into kinetic energy and compresses the refrigerant by the kinetic energy. The compressor includes a motor generating a driving force and a compression mechanism receiving the driving force of the motor to compress the refrigerant. In addition, there are various types of rotary compressors, scroll compressors, reciprocal compressors, etc. according to the compression mechanism for compressing the refrigerant.

Among these compressors, rotary compressors and scroll compressors are mainly used in air conditioners.

On the other hand, the most important factor in the process of researching and manufacturing the air conditioner as described above is to minimize the manufacturing cost and to minimize the energy consumption during operation of the air conditioner in order to increase the competitiveness of the product.

In particular, as the price of oil increases due to the recent increase in the amount of oil used worldwide, research and development of an air conditioner capable of minimizing power consumption has emerged as a very important task. And minimizing the power consumption of the air conditioner to minimize the cause of environmental problems.

On the other hand, the condition for operating the air conditioner so as to minimize the power consumption of the air conditioner is to operate the air conditioner according to the load of the indoor space where the air conditioner is installed, that is, the temperature condition. That is, when the temperature of the room rises sharply, the air conditioner is operated to generate a lot of cool air according to the excessive temperature change (excessive load) in order to maintain the set room temperature. In this case, the air conditioner is operated so that little cold air is generated to maintain the set room temperature.

One of the factors for satisfying such a condition is to control the amount of refrigerant discharged from the compressor, which is a main component for operating a refrigeration cycle system. Suction, compression, and discharge are performed continuously. If a lot of load is generated and a large capacity is desired (hereinafter, a power mode), each of the compression units may be driven. At this time, the capacity of the compressor will be the sum of the refrigerant discharged by each compression unit. If the load is reduced and you want to achieve the power saving effect (hereinafter, save mode), some of the compression units block the refrigerant intake or fix the vane with a piece after retreating. Eliminating the compartment of the compression chamber causes the rolling piston to idling the refrigerant without compressing it.

The method of fixing the vane back in the saving mode requires a separate component such as a piece and a space for mounting the component, and increases the number of manufacturing processes. In addition, since the pieces are repeatedly impacted on the vanes, the surface may be damaged as time passes, and reliability problems such as wear or foreign matters may be caused.

As another method, one of the methods of controlling the discharge capacity of the refrigerant discharged from the compressor is to apply an inverter motor capable of varying the number of rotations of the drive motor constituting the compressor. The discharge flow rate of the refrigerant discharged from the compressor is controlled by adjusting the rotation speed of the driving motor of the compressor according to the change of the condition of the room where the air conditioner is installed. The amount of heat and cold air generated in the condenser and the evaporator is adjusted according to the change in the discharge flow rate discharged from the compressor.

However, when the drive motor of the compressor is applied as an inverter motor, the price of the inverter motor becomes very expensive, thereby increasing the unit price of the product, which has a disadvantage in that the price competitiveness is lowered.

Therefore, it is required to adjust the discharge flow rate of the refrigerant compressed by the compressor while applying a general constant speed motor without a control drive to the compressor to vary the capacity of the air conditioner according to the room temperature condition in which the air conditioner is installed.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a multi-stage rotary compressor that can not only vary the capacity according to the change of room temperature, but also minimize the manufacturing cost. have.

In addition, an object of the present invention is to provide a multi-stage rotary compressor that can have a power saving effect while using all of a plurality of compression units in a saving mode for reducing a discharge amount of a refrigerant.

In order to achieve the object of the present invention, a casing having a sealed space formed therein; A driving unit mounted to the casing to generate a driving force; A first compression unit and a second compression unit receiving a driving force from the drive unit to compress the refrigerant; A first suction pipe guiding the refrigerant to the first compression unit; A first control valve mounted to the first suction pipe to control the suction refrigerant; A second suction pipe for guiding the refrigerant to the second compression unit; A chamber for temporarily storing the refrigerant discharged from the second compression unit by covering a second discharge valve that regulates the discharge refrigerant of the second compression unit; A second control valve installed on the chamber; And a connecting pipe connecting the chamber and the first control valve, such that the refrigerant discharged from the second compression unit is directly sucked into the first compression unit and compressed or discharged once in each compression unit. Provided is a multi-stage rotary compressor, wherein the refrigerant is selectively guided.

Hereinafter, the multi-stage rotary compressor according to the present invention will be described in detail with reference to an embodiment shown in the accompanying drawings.

1 is a longitudinal sectional view showing a first embodiment of the present invention.

As shown here, the multi-stage rotary compressor of the present invention includes a casing 100 having a sealed space therein; A driving unit 200 mounted to the casing 100 to generate a driving force; A first compression unit 300 and a second compression unit 400 receiving a driving force from the drive unit 200 to compress the refrigerant; A first suction pipe 710 for guiding a refrigerant to the first compression unit 300; A first control valve 500 mounted to the first suction pipe 710 to control the suction refrigerant; A second suction pipe 730 for guiding the refrigerant to the second compression unit 400; A chamber 740 for temporarily storing the refrigerant discharged from the second compression unit 400 by covering the second discharge valve 470 intermitting the discharge refrigerant of the second compression unit 400; A second control valve (600) installed on the chamber (740); And a connection pipe 720 connecting the chamber 740 and the first control valve 500. The refrigerant discharged from the second compression unit 400 is directly sucked into the first compression unit 300. It is characterized in that the refrigerant is selectively guided to be discharged after being compressed or compressed once in each compression unit (300, 400).

The casing 100 is installed through the discharge pipe 110, the first suction pipe 710, and the second suction pipe 730.

The drive unit 200 is fixed to the inside of the casing (100) for applying power from the outside and the stator 210 is disposed while leaving a predetermined gap inside the stator 210 to rotate while interacting with the stator The rotor 220 and the rotor 220 are formed integrally to transmit the driving force to each compression unit (300, 400) consists of a rotating shaft 230 having two eccentric parts.

The drive unit 200 is preferably composed of a constant speed motor. Constant speed motors generally have the advantage of being less expensive than inverter motors with control drives.

The compression unit is composed of a first compression unit 300 and the second compression unit 400, the first compression unit 300 is formed in an annular first cylinder 310 to be installed in the casing 100 ), An upper bearing 320 and an intermediate bearing 350 which radially support the rotating shaft 230 while forming the first inner space 330 together by covering both the upper and lower sides of the first cylinder 310, and the The first rolling piston 340 is inserted into the upper eccentric portion of the rotary shaft 230 to compress the refrigerant while turning in the first inner space 330 of the first cylinder 310, and the first rolling piston 340 A first vane configured to be movably coupled to the first cylinder 310 to be pressed against the outer circumferential surface so as to partition the first inner space 330 of the first cylinder 310 into a first suction chamber and a first compression chamber ( Not shown), and the opening and closing at the tip of the first discharge hole 360 formed to communicate with the first compression chamber in the upper bearing 320 The first discharge valve 370 may be configured to be coupled to control the discharge of the refrigerant discharged from the first compression chamber.

The second compression unit 400 is formed in an annular shape and positioned below the first cylinder 310 and in contact with the intermediate bearing 350, and an upper surface of the second cylinder 410. A lower bearing 450 supporting the rotating shaft 230 in the radial and axial directions while being coupled to the second inner space 430 together with the lower eccentric portion of the rotating shaft 230 to be rotatably coupled to the Compression of the second rolling piston 440 located in the second inner space 430 of the second cylinder 410, and the radial direction to the second cylinder 410 to be in pressure contact with the outer peripheral surface of the second rolling piston 440 A second vane (not shown) which is movably coupled to each other and divides the second internal space 430 of the second cylinder 410 into a second suction chamber and a second compression chamber, and one side of the lower bearing 450. A second coupled to the front end of the second discharge hole 460 formed so as to communicate with the second compression chamber The discharge valve 470 is formed.

The volume of the first internal space 330 of the first cylinder 310 and the volume of the second internal space 430 of the second cylinder 410 may be the same, but different from each other for more careful capacity change. It is preferable to form.

The first suction pipe 710 and the second suction pipe 730 are connected to an accumulator 130 whose suction side separates gaseous liquid from the refrigerant. The accumulator 130 sends only gas components to the first suction pipe 710 and the second suction pipe 730 after gas-liquid separation from one accumulator 135 that receives a refrigerant from the outside. One of the first or second suction pipes may be directly connected to the compression unit without passing through the accumulator 130.

The first control valve 500 is preferably composed of a three way valve. The first control valve 500 may be connected to a microprocessor for controlling the valve.

The chamber 740 is installed in a lower part of the second compression unit 400 (more precisely, lower part of the lower bearing 450) to maintain airtightness so that refrigerant does not leak.

The chamber 740 is preferably designed to simultaneously perform a role of a muffler to realize low noise during operation of the compressor.

The second control valve 600 is a type of check valve, and includes a first communication hole 630 communicating with the chamber 740; A housing (650) covering the first communication hole (630); An on / off valve 610 located inside the housing 650 to open and close the first communication hole 630; A spring 620 connected to one side of the on / off valve 610; The through-hole formed on one side of the housing 650 is configured to include a second communication hole 640 in communication with the case 100.

Hereinafter, the operation and effects of the present invention will be described.

2 is a cross-sectional view showing the operation in the power mode according to the first embodiment of the present invention.

As shown in the drawing, first, in the case of a power mode in which a required amount of refrigerant is large, the first control valve 500 is manipulated to operate the first control valve 500 without the refrigerant flowing into the first compression unit 300. Allow refrigerant to enter. In addition, the refrigerant is introduced into the second compression unit 400 through the second suction pipe 730.

When the power is applied to the drive unit 200, the rotating shaft 230 rotates and the first rolling piston 340 and the second rolling piston 440 is pivoting in the inner space (330, 430) of each cylinder A volume is formed between the first vane (not shown) and the second vane (not shown) to suck the refrigerant. Some of the refrigerant via the accumulator 130 is sucked into the first compression unit 300 through the first suction pipe 710, is compressed, and discharged into the casing 100 through the first discharge hole 360. The remaining refrigerant via the accumulator 130 is sucked into the second compression unit 400 through the second suction pipe 730 and is compressed to be discharged into the chamber 740 through the second discharge hole 460. When the refrigerant discharged into the chamber 740 is above a predetermined pressure, the pressing force becomes larger than the spring 620 of the second control valve 600 to push the on / off valve 610 and communicate with the first communication hole 630. It is discharged into the casing 100 through the hole 640. The refrigerant discharged from the first compression unit 300 and the second compression unit 400, respectively, saturates the inside of the casing 100 and repeats the process of being discharged to the outside of the casing 100 through the discharge pipe.

As described above, in the power mode, the first and second compression units are connected in parallel, respectively, are compressed and discharged, are combined in the casing 100, and then moved to the outside of the compressor through the discharge pipe. Compared with the discharge amount of the refrigerant.

3 is a cross-sectional view showing an operation in a saving mode according to a first embodiment of the present invention.

As shown in the drawing, by operating the first control valve 500 to prevent the suction refrigerant passing through the accumulator 130 to the first compression unit 300, and only the refrigerant via the connection pipe 720 The first compression unit 300 to be introduced. The refrigerant passing through the accumulator 130 is sucked and compressed into the second compression unit 400 through the second suction pipe 730 and then discharged into the chamber 740 through the second discharge hole 460. Refrigerant, which was temporarily stored in the chamber 740, is sucked into the first compression unit 300 through the connection pipe 720 and recompressed. The recompressed refrigerant is discharged into the casing 100 through the first discharge hole 360 and guided to the external refrigeration system through the discharge tube. At this time, since the pressure inside the casing 100 is higher than the pressure in the chamber 740 as the discharge pressure, the opening / closing valve 610 of the second control valve 600 is not opened and the refrigerant inside the chamber 740 is entirely connected. It is introduced into the first compression unit 300 through the tube (720).

As such, in the saving mode, the refrigerant once compressed in the second compression unit 400 is moved back to the first compression unit 300 and recompressed. That is, since the compression unit is connected in series and the refrigerant is discharged while passing through the second compression unit 400 and the first compression unit 300 sequentially, the discharge amount of the refrigerant is relatively small, but a high compression ratio can be obtained. In addition, in order to obtain an appropriate discharge pressure, a two-stage compression process is performed. In particular, in the case of the first compression unit 300, since the refrigerant compressed to some extent by the second compression unit 400 is sucked, the power consumption is particularly low. Holding Therefore, in the saving mode, the sum of the required powers of the first and second compression units is smaller than that in the power mode, thereby achieving a power saving effect.

In addition, the present invention has the effect of lowering the manufacturing cost because it is possible to realize the variable capacity by implementing the power mode and the saving mode by using a relatively low-cost constant speed motor without using an expensive inverter motor with a control unit.

Hereinafter, a second embodiment of the present invention will be described. 4 is a longitudinal sectional view showing a second embodiment of the present invention. The same reference numerals are given to the same configuration as in the first embodiment, and description thereof will be omitted.

As shown therein, the multi-stage rotary compressor of the present invention includes a casing 100 having a sealed space therein; A driving unit 200 mounted to the casing 100 to generate a driving force; A first compression unit 300 and a second compression unit 400 receiving a driving force from the drive unit 200 to compress the refrigerant; A first suction pipe 710 for guiding a refrigerant to the first compression unit 300; A third control valve 520 mounted to the first suction pipe 710 to control the suction refrigerant; A second suction pipe 730 for guiding the refrigerant to the second compression unit 400; A chamber 740 for temporarily storing the refrigerant discharged from the second compression unit 400 by covering the second discharge valve 470 intermitting the discharge refrigerant of the second compression unit 400; A second control valve (600) installed on the chamber (740); A connection pipe 720 connecting the chamber 740 and the first suction pipe 710; And a fourth control valve 510 mounted on the connection pipe 720 to control the refrigerant, and the refrigerant discharged from the second compression unit 400 is directly sucked into the first compression unit 300. It is characterized in that the refrigerant is selectively guided to be discharged after being compressed or compressed once in each compression unit (300, 400).

Preferably, the third control valve 520 and the fourth control valve 510 are configured as two way valves. The third control valve 520 and the fourth control valve 510 may be connected to a microprocessor for control.

FIG. 7 is a longitudinal sectional view showing a third embodiment of the present invention. As shown therein, an actuator 800 is disposed on the connection pipe 720 instead of the fourth control valve 510 to cool the refrigerant. It can also be configured to control the flow of.

Hereinafter, the operation and effect of the second embodiment of the present invention will be described.

5 is a cross-sectional view showing operation in a power mode according to a second embodiment of the present invention.

As shown in the drawing, first, in the case of a power mode in which a required amount of refrigerant is large, the third control valve 520 is opened, and the fourth control valve 510 is closed to form a first through the first suction pipe 710. The refrigerant flows into the compression unit 300, and the refrigerant flows into the second compression unit 400 through the second suction pipe 730. The refrigerant introduced into the first compression unit 300 is discharged into the casing 100 through the first discharge hole 360 after compression. The refrigerant introduced into the second compression unit 400 is discharged into the chamber 740 through the second discharge hole 460 after compression. When the refrigerant discharged into the chamber 740 is above a predetermined pressure, the pressing force becomes larger than the spring 620 of the second control valve 600 to push the on / off valve 610 and communicate with the first communication hole 630. It is discharged into the casing 100 through the hole 640. The refrigerant discharged from the first compression unit 300 and the second compression unit 400, respectively, saturates the inside of the casing 100 and repeats the process of being discharged to the outside of the casing 100 through the discharge tube.

6 is a cross-sectional view showing operation in a saving mode according to a second embodiment of the present invention.

As shown in the drawing, the third control valve 520 is closed and the fourth control valve 510 is opened to prevent the intake refrigerant passing through the accumulator 130 from entering the first compression unit 300. Only the refrigerant passing through the tube 720 is introduced into the first compression unit 300. The refrigerant passing through the accumulator 130 is sucked and compressed into the second compression unit 400 through the second suction pipe 730 and then discharged into the chamber 740 through the second discharge hole 460. Refrigerant, which was temporarily stored in the chamber 740, is sucked into the first compression unit 300 through the connection pipe 720 and recompressed. The recompressed refrigerant is discharged into the casing 100 through the first discharge hole 360 and guided to the external refrigeration system through the discharge tube. At this time, since the pressure inside the casing 100 is higher than the pressure in the chamber 740 as the discharge pressure, the opening / closing valve 610 of the second control valve 600 is not opened and the refrigerant inside the chamber 740 is entirely connected. It is introduced into the first compression unit 300 through the tube (720).

As described above, the multistage rotary compressor of the present invention has the following effects.

First, in the present invention, since the refrigerant once compressed is recompressed again, a high discharge pressure can be achieved, and volumetric efficiency is improved. In addition, since the refrigerant once compressed is used during recompression, leakage into the casing, which is the discharge pressure, may be reduced, and the amount of heat transferred to the low temperature refrigerant at the suction side may be greatly reduced.

Second, the present invention does not require separate parts and mounting space, compared to the method of retracting the vane in the saving mode, the manufacturing process is simple. In addition, since a piece for retreating and fixing the vane is not necessary, wear and foreign matters are not generated, thereby improving reliability.

Third, the efficiency of the motor and the compressor is improved because all of the plurality of compression units are used even in the saving mode. In addition, since the refrigerant is compressed once again compared to the power mode, the required power is reduced, thereby saving power.

Fourth, it is possible to reduce the manufacturing cost by varying the capacity while using a low-speed constant speed motor.

Claims (10)

A casing having a sealed space formed therein; A driving unit mounted to the casing to generate a driving force; A first compression unit and a second compression unit receiving a driving force from the drive unit to compress the refrigerant; A first suction pipe guiding the refrigerant to the first compression unit; A first control valve mounted to the first suction pipe to control the suction refrigerant; A second suction pipe for guiding the refrigerant to the second compression unit; A chamber for temporarily storing the refrigerant discharged from the second compression unit by covering a second discharge valve that regulates the discharge refrigerant of the second compression unit; A second control valve installed on the chamber; And a connecting pipe connecting the chamber and the first control valve, such that the refrigerant discharged from the second compression unit is directly sucked into the first compression unit and compressed or discharged once in each compression unit. A multistage rotary compressor, wherein the refrigerant is selectively guided. The multistage rotary compressor according to claim 1, wherein the first control valve is a three-way valve. A casing having a sealed space formed therein; A driving unit mounted to the casing to generate a driving force; A first compression unit and a second compression unit receiving a driving force from the drive unit to compress the refrigerant; A first suction pipe guiding a refrigerant to the first compression unit; A third control valve mounted to the first suction pipe to control the suction refrigerant; A second suction pipe for guiding the refrigerant to the second compression unit; A chamber for temporarily storing the refrigerant discharged from the second compression unit by covering a second discharge valve that regulates the discharge refrigerant of the second compression unit; A second control valve installed on the chamber; A connecting pipe connecting the chamber and the first suction pipe; A fourth control valve mounted on the connection pipe to control the refrigerant; the refrigerant discharged from the second compression unit is directly sucked into the first compression unit and compressed or discharged once in each compression unit. Multi-stage rotary compressor, characterized in that to guide the refrigerant selectively. 4. The valve of claim 1 or 3, wherein the second control valve comprises: a first communication hole communicating with the chamber; A housing covering the first communication hole; An on / off valve positioned inside the housing to open and close the first communication hole; A spring connected to one side of the on / off valve; And a second communication hole formed in one side of the housing to communicate with the case. The multistage rotary compressor according to claim 1 or 3, wherein the drive unit is composed of a constant speed motor. The multistage rotary compressor of claim 1 or 3, wherein the first and second compression units have different volumes of internal spaces for sucking and compressing the compressed refrigerant. The multistage rotary compressor according to claim 1 or 3, wherein only one of the first suction pipe and the second suction pipe is connected to the accumulator. The multistage rotary compressor according to claim 1 or 3, wherein the suction sides of the first suction pipe and the second suction pipe are respectively connected to an accumulator separating gas liquid from the refrigerant. 4. The multistage rotary compressor of claim 3, wherein the third control valve and the fourth control valve are anisotropic valves, respectively. 4. The multistage rotary compressor of claim 3, wherein the third control valve is an anisotropic valve, and the fourth control valve is an actuator disposed on the connection pipe to control the flow of the refrigerant.

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