KR20100000370A - Variable capacity type rotary compressor - Google Patents

Abstract

PURPOSE: A variable capacity type rotary compressor is provided to connect an intake pipe to multiple cylinders and to prevent refrigerant of an idling cylinder from flowing backward to the other side cylinder. CONSTITUTION: A variable capacity type rotary compressor comprises a casing(100), a plurality of cylinders(310,410), an intake pipe(140), a plurality of rolling pistons(320,420), a plurality of vanes, and a vane binding unit. The cylinder has compression spaces(V1,V2) and intake ports(312,412). The intake pipe divides and supplies refrigerant to inlet ports of the cylinders. The vane divides the compression space along with the rolling piston into an intake space and an ejection space. The vain binding unit restricts and releases the vane of the cylinder in order to vary an operation mode. The intake pipe is connected to the intake port of a first cylinder located in the upper side.

Description

Variable Capacity Rotary Compressor {VARIABLE CAPACITY TYPE ROTARY COMPRESSOR}

The present invention relates to a variable displacement rotary compressor capable of selecting a power operation and a saving operation.

Generally, a refrigerant compressor is applied to a vapor compression refrigeration cycle (hereinafter, referred to as a refrigeration cycle) such as a refrigerator or an air conditioner. The refrigerant compressor has been introduced is a constant-speed compressor that is driven at a constant speed or an inverter compressor of which the rotational speed is controlled.

The refrigerant compressor is a hermetic compressor, in which a drive motor which is a motor and a compression unit operated by the drive motor are installed together in an inner space of a closed casing, is called a hermetic compressor. It can be called a compressor. Most domestic or commercial refrigeration equipment is a hermetic compressor. The refrigerant compressor may be classified into a reciprocating type, a scroll type, a rotary type, and the like according to a method of compressing the refrigerant.

The rotary compressor is a method of compressing a refrigerant by using a rolling piston that makes an eccentric rotation in a compression space of a cylinder and a vane that contacts the rolling piston and divides the compression space of the cylinder into a suction chamber and a discharge chamber. Recently, a variable displacement rotary compressor that can vary the refrigeration capacity of the compressor according to the load change has been introduced. As a technique for varying the refrigeration capacity of the compressor, a technique of applying an inverter motor and a technique of varying the volume of the compression chamber by bypassing a part of the refrigerant to be compressed to the outside of the cylinder are known. However, when the inverter motor is applied, the price of the driver for driving the inverter motor is about 10 times higher than that of the constant speed motor, which increases the production cost of the compressor. This complexity has the disadvantage that the efficiency of the compressor is lowered as the flow resistance of the refrigerant is increased.

In view of this, a so-called independent suction displacement variable rotary compressor (hereinafter, abbreviated as an independent suction rotary compressor) has been introduced, which includes a plurality of cylinders and at least one of the plurality of cylinders is capable of idling. In this case, the plurality of cylinders are configured so that the suction pipes are independently provided so that both cylinders can be operated independently.

However, in the case of the independent suction rotary compressor as described above, since the suction pipes must be independently connected to both cylinders, there is a problem in that the manufacturing cost increases as the assembly labor increases significantly.

In addition, as both cylinders are connected by both suction pipes, there is a problem in that a high-temperature refrigerant flows backward in the idle cylinder, thereby degrading compressor performance.

In addition, when a plurality of suction pipes are connected, the welding process is not secured in close proximity to other members, and thus, the assembly process cannot be automated, thereby increasing the manufacturing cost.

The present invention solves the problems of the conventional variable displacement rotary compressor as described above, by using a single suction pipe in a double rotary compressor having a plurality of cylinders in common to reduce the number of parts and assembly labor and to automate the assembly process It is an object of the present invention to provide a variable capacity rotary compressor that can improve the performance of the compressor by effectively varying the capacity of the compressor efficiently while reducing the manufacturing cost significantly.

In order to solve the object of the present invention, the inner space is sealed casing; A plurality of cylinders installed on upper and lower sides of the inner space of the casing, each of the compression spaces formed independently of each other, and each of the suction ports communicating with each other so as to communicate with each of the compression spaces; A suction pipe configured to distribute the refrigerant to the suction ports of the plurality of cylinders; A plurality of rolling pistons compressing the refrigerant while pivoting in the compression spaces of the cylinders; A plurality of vanes for separating the compression spaces of the cylinders into the suction space and the discharge space together with the rolling pistons; And a vane confinement unit configured to change an operation mode of the compressor by restraining or releasing the vane of at least one of the vanes, wherein the suction pipe is disposed at the inlet of the first cylinder located above the plurality of cylinders. There is provided a variable displacement rotary compressor.

In the variable displacement rotary compressor according to the present invention, the refrigerant sucked into one suction pipe is alternately sucked into each compression space through a cylinder located above the plurality of cylinders, thereby independently coupling the suction pipes to the respective cylinders. In addition to the reduction in the number of parts, as well as the assembly labor for connecting the suction pipe to the casing and accumulator can be reduced significantly the production cost.

In addition, as the plurality of cylinders directly communicate with each other and one suction tube is connected therebetween, the refrigerant in the idle cylinder may be prevented from flowing back to the other cylinder, thereby improving the performance of the compressor.

In addition, when only one suction pipe is connected, a welding space necessary for the operation of the welding robot can be secured when connecting the suction pipe as well as other connection pipes (particularly, the common side connection pipe) constituting the mode switching unit. This can greatly reduce the manufacturing cost.

Hereinafter, a variable displacement rotary compressor according to the present invention will be described in detail with reference to an embodiment shown in the accompanying drawings.

As shown in FIG. 1, the variable displacement rotary compressor 1 according to the present invention comprises the evaporator 4 to form part of a closed loop refrigeration cycle leading to the condenser 2, the expansion valve 3, and the evaporator 4. The suction side is connected to the outlet side of the outlet and the discharge side is connected to the inlet side of the condenser 2. The accumulator 5 is connected between the outlet side of the evaporator 4 and the inlet side of the compressor 1 so as to separate the gas refrigerant and the liquid refrigerant from the refrigerant transferred from the evaporator 4 to the compressor 1. do.

As shown in FIG. 2, the compressor 1 is provided with a transmission unit 200 generating a driving force in an upper side of the inner space of the closed casing 100, and the transmission unit 200 below the inner space of the casing 100. The first compression unit 300 and the second compression unit 400 for compressing the refrigerant by the power generated in the) is installed. In addition, a mode switching unit 500 is installed outside the casing 100 to switch the operation mode of the compressor such that the second compression unit 400 idles if necessary.

The casing 100 maintains a state of the discharge pressure by the refrigerant discharged from the first compression unit 300 and the second compression unit 400 or the first compression unit 300, the inner space of the casing 100, One gas suction pipe 140 is connected to the lower main surface of the lower portion 100 so that the refrigerant is sucked into the first compression part 300, and the first compression part 300 and the second compression part are connected to the upper end of the casing 100. One gas discharge pipe 150 is connected to the refrigerant compressed and discharged at 400 to be transferred to the refrigeration system. The gas suction pipe 140 is inserted into the intermediate connecting pipe (not shown) inserted into the communication hole 131 of the intermediate bearing 130 to be described later is welded.

The transmission unit 200 is a stator 210 fixed to the inner circumferential surface of the casing 100, a rotor 220 rotatably disposed inside the stator 210, and the rotor 220 Shrink is made of a rotating shaft 230 to rotate together. The electric motor 200 may be a constant speed motor or an inverter motor. However, in consideration of the cost, the electric motor 200 may vary the operation mode of the compressor by idling one of the first compression part 300 and the second compression part 400 if necessary while using the constant speed motor. Can be.

In addition, the rotation shaft 230 includes a shaft portion 231 coupled to the rotor 220, and a first eccentric portion 232 and a second eccentric portion 233 which are eccentrically formed on both left and right sides of the lower end of the shaft portion 231. ) The first eccentric portion 232 and the second eccentric portion 233 are formed symmetrically with a phase difference of approximately 180 °, and the first rolling piston 340 and the second rolling piston 430, which will be described later, are rotatable, respectively. Combined.

The first compression unit 300 is formed in an annular shape and rotatably coupled to the first cylinder 310 installed inside the casing 100 and the first eccentric portion 232 of the rotation shaft 230. A first rolling piston 320 that rotates in the first compression space V1 of the first cylinder 310 and compresses the refrigerant, and is coupled to the first cylinder 310 so as to be movable in a radial direction. A first vane 330 in which a sealing surface is in contact with the outer circumferential surface of the first rolling piston 320 and partitions the first compression space V1 of the first cylinder 310 into a first suction chamber and a first discharge chamber, respectively; And a vane spring 340 made of a compression spring to elastically support the rear side of the first vane 330. Reference numeral 350 denotes a first discharge valve, and 360 denotes a first muffler.

The second compression unit 400 is formed in an annular shape, the second cylinder 410 installed below the first cylinder 310 in the casing 100 and the second eccentric portion of the rotary shaft 230 ( A second rolling piston 420 rotatably coupled to 233 and compressing the refrigerant while turning in the second compression space V2 of the second cylinder 410, and radially to the second cylinder 410. The second compression space V2 of the second cylinder 410 is partitioned into a second suction chamber and a second discharge chamber, respectively, to be movable and coupled to the outer circumferential surface of the second rolling piston 420. The second vane 430 is spaced apart from the outer circumferential surface of the piston 420 so that the second suction chamber and the second discharge chamber communicate with each other. Reference numeral 440 denotes a second discharge valve, and 450 denotes a second muffler.

Here, an upper bearing plate (hereinafter referred to as an upper bearing) 110 is covered on the upper side of the first cylinder 310, and a lower bearing plate (hereinafter referred to as a lower bearing) 120 is provided below the second cylinder 410. Is covered, and an intermediate bearing plate (hereinafter, intermediate bearing) 130 is interposed between the lower side of the first cylinder 310 and the upper side of the second cylinder 410 together with the first compression space V1 and the second. The rotation shaft 230 is supported in the axial direction while forming the compression space V2.

As shown in FIGS. 3 and 4, the upper bearing 110 and the lower bearing 120 are formed in a disc shape, and the center portion 231 of the rotary shaft 230 is radially supported at each center thereof. The bearing parts 112 and 122 having the yokes 111 and 121 protrude. In addition, the intermediate bearing 130 is formed in an annular shape having an inner diameter such that the eccentric portion of the rotary shaft 230 penetrates, and the first suction port 312 and the second suction port 412 communicate with one side thereof. The hole 131 is formed.

In the first cylinder 310, a first vane slot 311 is formed on one side of an inner circumferential surface of the first compression space V1 such that the first vane 330 linearly reciprocates, and the first vane slot is formed. A first suction port 312 is formed at one side of the 311 to guide the refrigerant into the first compression space V1, and the other side of the first vane slot 311 has a refrigerant inside the second muffler 360. A first discharge guide groove (not shown) for discharging into the space is formed to be inclined by chamfering at the corner opposite to the first suction port 312.

The second cylinder 410 has a second vane slot 411 is formed on one side of the inner peripheral surface constituting the second compression space (V2) so that the second vane 430 linearly reciprocates, the second vane slot A second suction port 412 is formed at one side of the 411 to guide the refrigerant into the second compression space V2, and at the other side of the second vane slot 411, the refrigerant is inside the second muffler 450. A second discharge guide groove (not shown) for discharging into the space is formed to be inclined by chamfering at the corner opposite to the second suction port 412.

The first suction port 312 is formed through the radial direction, the through hole 313 in the axial direction so as to communicate with the lower end of the communication hole 131 of the intermediate bearing 130 in the middle of the first suction port 312. ) Is formed.

The second suction port 412 is chamfered so as to be inclined toward the inner circumferential surface of the second cylinder 410 from the bottom edge of the second cylinder 410 in contact with the upper end of the communication hole 131 of the intermediate bearing 130. Is formed.

Here, as shown in FIG. 5, the second suction port 412 is formed such that the radial center line L1 intersects the axial center O of the fourth cylinder 410 having the second suction port 412 in planar projection. do. The same also applies to the first suction port 412.

As shown in FIG. 3, the first vane slot 311 is formed by cutting the first vane 330 by a predetermined depth in a radial direction to reciprocate in a straight line, and the first vane slot 311. In the rear side, that is, the outer end side of the) as shown in Figure 4 is formed through hole 312 through the axial direction so as to communicate with the inner space of the casing (100). The vane spring 340 is installed in the through hole 313 of the first cylinder 310.

The second vane slot 411 is formed by cutting the second vane 430 by a predetermined depth in a radial direction so that the second vane 430 reciprocates in a straight line, and is the rear side of the second vane slot 411, that is, the outer side. The vane chamber 413 is formed at the end side so as to communicate with the common side connecting pipe 530 to be described later. The vane chamber 413 is hermetically coupled to the inner space of the casing 100 by an intermediate bearing 130 and a lower bearing 120 in contact with the upper and lower surfaces thereof.

And the vane chamber 413, the front side is in communication with the vane chamber 413, while the rear side is an intermediate connecting pipe (not shown) to be welded and connected to the common side connection pipe 530 is pressed into the coupling Can be. The vane chamber 413 has a rear surface of the second vane 430 even when the second vane 430 is completely retracted to be stored inside the second vane slot 411. It is formed to have a predetermined internal volume to form a pressing surface with respect to the refrigerant supplied through.

Here, as shown in FIG. 6, the second vane 430 has a pressing surface 432 such that the sealing surface 431 is in contact with or spaced apart from the second rolling piston 420 according to the operation mode of the compressor. Since the second vane 430 is supported by the refrigerant of the suction pressure or the refrigerant of the discharge pressure filled in the vane chamber 413, the inside of the second vane slot 411 in a certain operating mode of the compressor, that is, the saving mode. The second vane 430 should be restrained in order to prevent compressor noise or efficiency decrease due to the shaking of the second vane 430. To this end, a method of restraining the second vane using the internal pressure of the casing as shown in FIG. 7 may be proposed.

For example, the second cylinder 410 has a high pressure side vane constraining passage (hereinafter referred to as a 'first constraining passage') 414 perpendicular to or perpendicular to the direction of motion of the second vane 430. ) Is formed. The first restriction passage 414 allows the inside of the casing 100 to communicate with the second vane slot 411 so that the refrigerant having a discharge pressure filled in the inner space of the casing 100 is the second vane 430. To the opposite vane slot face to restrain. In addition, a low pressure side vane restriction flow passage (hereinafter referred to as a “second restraint flow passage”) in which the second vane slot 411 and the second suction port 412 communicate with the first restraint flow passage 414. 415 may be formed. The second constrained passage 415 is a pressure difference with the first constrained passage 414 while the refrigerant of the discharge pressure flowing through the first constrained passage 414 exits to the second constrained passage 415. The second vane 430 may serve to be quickly restrained while going.

The first restriction passage 414 is located at the discharge guide groove (unsigned) of the second cylinder 410 with respect to the second vane 430 to form a second vane slot on the outer circumferential surface of the second cylinder 410. It may be formed through the center of the 411. In addition, the first restriction passage 414 is narrowly formed in the second vane slot 411 in two stages by using a two-stage drill, so that the linear movement of the second vanes 430 may be stably performed. An outlet end thereof may be formed approximately in the middle of the second vane slot 411 in the longitudinal direction. In addition, the first restriction passage 414 is formed at a position in communication with the vane chamber 413 through a gap between the second vane 430 and the second vane slot 411 during the power operation of the compressor. The refrigerant of the discharge pressure flowing through the first constraining passage 414 may be introduced into the vane chamber 413 to increase the rear pressure of the second vane 430. When the second vane 430 is constrained and the first constraining flow passage 414 communicates with the vane chamber 413, the pressure of the vane chamber 413 is increased to push the second vane 430 out of the second vane 430. Since the shaking of the 430 may occur, the first restriction passage 414 may be formed to be located within the reciprocating range of the second vane 430.

In addition, the first restriction passage 414 has a cross-sectional area of the second vane 430 that is smaller than or equal to the cross-sectional area of the pressing surface 432 of the second vane 430 through the vane chamber 413. Excessive restraint can be prevented. For example, the cross-sectional area of the first restraint flow passage 414 is the cross-sectional area of the first restraint flow passage as the vane area of the second vane 430, that is, the vane area of the side where the second vane 430 receives the restraint pressure. It may be desirable to form a specific range when dividing to minimize the mode switching noise.

In addition, although not shown in the drawings, the first restriction passage 414 may be formed to be negatively formed at a predetermined depth on both upper and lower surfaces of the second cylinder 410, and may be coupled to upper and lower surfaces of the second cylinder 410. The intermediate bearing 130 or the lower bearing 120 may be formed in a negative shape or penetrates to a predetermined depth. Here, when the second constraining passage 415 is formed negatively on the upper surface of the lower bearing 120 or the lower surface of the intermediate bearing 130, the second cylinder 410 or the respective bearings 120 and 130 may be replaced. Forming together when sintering can reduce production costs.

The second restriction passage 415 causes a pressure difference between the discharge pressure and the suction pressure on both side surfaces perpendicular to the moving direction of the second vane 430, and the second vane 430 causes the second vane 430 to have a second pressure. Preferably, the second suction port 412 is formed to be inclined with respect to the axial direction, but preferably disposed on the same straight line as the first restriction channel 414 so as to be in close contact with the vane slot 411. It may be inclined or bent to communicate with 412.

The second constrained flow path 415 is formed at a position that can communicate with the vane chamber 413 through a gap between the second vane 430 and the second vane slot 411 during the saving operation of the compressor. Preferably, the discharge is filled in the vane chamber 413 when the second constrained passage 415 communicates with the vane chamber 413 when the second vane 430 moves forward during the power operation of the compressor. Since the refrigerant of the pressure Pd leaks into the second suction port 412 and may not sufficiently support the second vane 430, the second restriction passage 415 is located within the reciprocating range of the second vane 430. It may be desirable to be formed to.

Meanwhile, as shown in FIGS. 1 and 2, the mode switching unit 500 has one end connected to the low pressure side connecting pipe 510 branched from the gas suction pipe 140, and one end thereof to the inner space of the casing 100. One end is connected to the high pressure side connecting pipe 520 and the vane chamber 413 of the second cylinder 410 to selectively connect the low pressure side connecting pipe 510 and the high pressure side connecting pipe 520. The common mode connecting pipe 530 communicates with, the first mode switching valve 540 connected to the vane chamber 413 of the second cylinder 410 through the common side connecting pipe 530, and the first mode A second mode switching valve 550 is connected to the switching valve 540 to control the opening and closing operation of the first mode switching valve 540.

The other end of the low pressure side connecting pipe 510 is connected to the first inlet of the first mode switching valve 540, and the other end of the high pressure side connecting pipe 520 is the first mode switching valve 540. It is connected to the second inlet of, the common side connecting pipe 530 is the other end is connected to the outlet of the first mode switching valve 540. And both ends of the low pressure side connection pipe 510 is welded to the gas suction pipe 140 and the first mode switching valve 540, respectively, and both ends of the high pressure side connection pipe 520, respectively, more precisely, Intermediate connection pipe (100) sealingly coupled to the inner space of the casing) and the first mode switching valve 540 is welded and coupled, both ends of the common side connection pipe (530), respectively, the intermediate bearing (more precisely, Intermediate connecting pipe sealing to the intermediate bearing) 130 and the first mode switching valve 540 is welded. Here, as shown in FIGS. 8 and 9, at the first point A at which the gas suction pipe 140 is connected to the casing 100, a second point at which the common side connecting pipe 530 is connected to the casing 100. The distance L1 to (B) is not longer than the distance L2 from the point A to the third point C at which the high-pressure side connecting pipe 520 is connected to the casing, more preferably shorter. The second suction port 412 may be formed at a position close to the second vane slot 411 while being disposed radially, thereby increasing the volume of the compression space.

In addition, the points, that is, the first point A, the second point B, and the third point C, are not overlapped with each other in planar space, that is, each point A, B, C is The gas suction pipe 140 and the respective connecting pipes 520 and 530 are arranged to have different longitudinal distances ΔH1 and ΔH2 and different lateral distances ΔS1 and ΔS2. When the spot welding robot has a gap to weld, it is possible to automate the above welding operation. In particular, the first point (A) and the second point (B) can be located in close proximity for this purpose, it is most important whether the gap between the two points (A) (B).

The high pressure side connecting pipe 520 may communicate with the lower half of the casing 100, that is, the second compression unit 400, but in this case, the oil of the casing 100 may be in the vane chamber 413. ) Is excessively introduced into the compressor to delay the pressure change of the vane chamber 413 to change the mode of the compressor to increase the vane vibration, as well as the viscosity index between the second vane slot 411 and the second vane 430. By increasing the vane can inhibit the smooth operation. Therefore, the high-pressure side connecting pipe 520 is a height that is not submerged in oil so that the refrigerant of the discharge pressure filled in the inner space of the casing 100 can flow into the first mode switching valve 540, that is, in FIG. As described above, it may be preferable to communicate between the lower end of the transmission part 200 and the upper end of the first compression part 300. In this case, since a predetermined amount of oil must be supplied to the vane chamber 413 to lubricate between the second vane slot 411 and the second vane 430, a fine oil supply hole may be formed in the lower bearing 120. Not shown) may be formed so that the oil is supplied when the second vane 430 reciprocates.

The basic compression process of the variable displacement rotary compressor according to the present invention as described above is as follows.

That is, when the rotor 220 rotates by applying power to the stator 210 of the transmission unit 200, the rotation shaft 230 rotates together with the rotor 220 while the transmission unit 200 is rotated. The rotational force of the first compression unit 300 and the second compression unit 400, the first compression unit 300 and the second compression unit 400, respectively, the first rolling piston 320 and the first 2, the rolling piston 420 makes an eccentric rotational motion in each of the first and second compression spaces V1 and V2, and the first and second vanes 330 and 430 are respectively The refrigerant is compressed while forming compression spaces V1 and V2 having a phase difference of 180 ° together with the second rolling pistons 320 and 420.

For example, when the first compression space V1 starts the suction stroke, the refrigerant flows into the first suction port 312 of the first cylinder 310 through the accumulator 5 and the suction pipe 140, and the refrigerant Is sucked into the first compression space (V1) and compressed.

The second compression space V2 of the second cylinder 410 having a phase difference of 180 ° with the first compression space V1 is the suction stroke while the first compression space V1 is in the compression stroke process. Will start. At this time, the second suction port 412 of the second cylinder 410 is in communication with the communication hole 131, a portion of the refrigerant sucked into the first suction port 312 through the communication hole 131 It is introduced into the second suction port 412 of the two cylinder 410, the refrigerant is sucked into the second compression space (V2) is compressed.

On the other hand, in the variable capacity rotary compressor according to the present invention the process of varying the capacity is as follows.

That is, when the compressor or the air conditioner applying the same, the power is applied, the power is applied to the first mode switching valve 540 as shown in Figure 10 and 11 while the low pressure side connection pipe 510 is cut off The high pressure side connector 520 is connected to the common side connector (530). Accordingly, the high pressure gas inside the casing 100 is supplied to the vane chamber 413 of the second cylinder 410 through the high pressure side connecting pipe 520 so that the second vane 430 is the vane chamber 413. The refrigerant gas flowing into the second compression space (V2) is normally compressed and discharged while being pressed by the high pressure refrigerant filled in the inside of the second rolling piston 420.

At this time, the high pressure refrigerant gas or oil is supplied to the first restriction passage 414 provided in the second cylinder 410 to add one side of the second vane 430, but the first restriction passage ( As the cross-sectional area of 414 is narrower than the cross-sectional area of the second vane slot 411, the pressing force at the side surface is smaller than the forward and backward pressing force in the vane chamber 413 so that the second vane 430 cannot be restrained. . Accordingly, the second vane 430 is pressed against the second rolling piston 420 to compress the entire refrigerant sucked into the second compression space V2 while dividing the second compression space V2 into the suction chamber and the discharge chamber. Discharged. As a result, the compressor or the air conditioner using the same is 100% operated.

On the other hand, in the case of performing a saving operation such as when the compressor or the air conditioner to which the air is applied, the power is turned off to the first mode switching valve 540 as shown in FIGS. The low pressure side connection pipe 510 and the common side connection pipe 530 communicate with each other, and a portion of the low pressure refrigerant gas sucked into the second cylinder 410 flows into the vane chamber 413. Accordingly, the second vane 430 is pushed by the refrigerant compressed in the second compression space V2 and received inside the second vane slot 411, so that the suction chamber and the discharge chamber of the second compression space V2 communicate with each other. The refrigerant gas sucked into the second compression space V2 may not be compressed.

At this time, the pressure is added to one side of the second vane 430 by the first restraint passage 414 provided in the second cylinder 410 and the second vane by the second restraint passage 415. As a large pressure difference is generated between the pressures added to the other side of 430, the second vane is generated as the pressure applied through the first restraint passage 414 tends to move toward the second restraint passage 415. (430) can be quickly and surely restrained without trembling. In addition, when the pressure of the vane chamber 413 is switched from the discharge pressure to the suction pressure, the discharge pressure remains in the vane chamber 413 to form a kind of intermediate pressure Pm, but the vane chamber 413 The pressure of the vane chamber 413 is rapidly converted to the suction pressure Ps as the intermediate pressure Pm of the gas leaks through the second constrained flow passage 415 having a lower pressure than that of the second vane 430. It is possible to prevent the shaking phenomenon more quickly and thereby the second vane 430 is quickly and effectively restrained. Accordingly, as the second compression space V2 of the second cylinder 410 communicates with one space, the entire refrigerant sucked into the second compression space V2 of the second cylinder 410 is not compressed. The second rolling piston 420 moves along the trajectory of the second rolling piston 420, and a part of the refrigerant moves to the first compression space V1 through the communication hole 131 and the first suction port 312 by a pressure difference. As a result, the second compression unit 400 does not work. As a result, the compressor or the air conditioner applying the same operates only as much as the capacity of the first compression unit 300. In this process, as the refrigerant in the second compression space V2 moves to the first compression space V1 without being flowed back to the accumulator 5, the suction loss may be reduced by preventing overheating of the accumulator 5.

In this way, the refrigerant sucked into one suction tube is sucked through the cylinder located above the plurality of cylinders and alternately sucked into each compression space through the communication hole, thereby independently coupling the suction tubes to the respective cylinders. In addition, the number of parts can be reduced, as well as the number of assembly operations for connecting the suction pipe to the casing and the accumulator can be reduced, thereby greatly reducing the production cost.

In addition, as the plurality of cylinders directly communicate with each other and one suction tube is connected to one of the cylinders, the refrigerant in the idle cylinder may be prevented from flowing back to the other cylinder, thereby improving the performance of the compressor. For example, when the first cylinder and the second cylinder are connected to each other through an accumulator, the second compression space of the second cylinder, which idles during the saving operation of the compressor, is communicated with the accumulator, so that a certain amount of pressure is fixed in the second compression space. The compressed refrigerant flows back to the accumulator and is sucked into the first compression space of the first cylinder. As a result, the temperature of the accumulator is increased to increase the specific volume of the refrigerant, thereby reducing the amount of refrigerant sucked into the first compression space, thereby degrading compressor performance. However, as in the present invention, when both the first suction port and the second suction port are not directly connected to the accumulator, and only one cylinder is directly connected to the accumulator, the refrigerant almost flows into the first compression space during the saving operation of the compressor. Instead, as most refrigerant is sucked into the second compression space, which is relatively low pressure, the specific volume of the refrigerant sucked into the second compression space may be prevented from rising, thereby improving the performance of the compressor. As a result of measuring the internal temperature of the accumulator during the actual saving operation, when both cylinders are connected to the accumulator, the internal temperature of the accumulator is detected to be approximately 50 ℃, while both cylinders are not directly connected to the accumulator. In case of indirect connection through, the accumulator's internal temperature was maintained about 35 ℃. This is because the refrigerant flows back to the accumulator through the suction pipe connected to the cylinder which idles during the saving operation as both cylinders are connected to each suction pipe and the plurality of suction pipes are connected through one accumulator. It can be judged that. On the other hand, when one of the two cylinders is connected to one suction tube and the two cylinders are connected to each other, the refrigerant is continuously sucked and idling only to the cylinder which maintains a relatively low pressure state between the two cylinders. It can be judged that the phenomenon in which the refrigerant flows back hardly occurs. Accordingly, it can be seen that the performance of the overall compressor is improved.

In addition, when only one suction pipe is connected, a welding space necessary for the operation of the welding robot can be secured when connecting the suction pipe as well as other connection pipes (particularly, the common side connection pipe) constituting the mode switching unit. This can greatly reduce the manufacturing cost. As mentioned above, when there are a plurality of suction pipes, any one of the suction pipes of the spot welding robot generally welds using three to four torches as the common side connection pipes are arranged in close proximity. It is impossible to automate the welding operation without securing the welding space. Accordingly, since the worker has to weld each suction pipe and the connection pipe by hand, the working speed may be slowed down and the manufacturing cost may be excessively increased. However, when only one suction tube is applied as in the present invention, the welding space for the suction tube and the connection tubes can be automated while the welding space of the spot welding robot is secured. This simplifies and speeds up the assembly process of assembling the mode switching unit when manufacturing a variable displacement rotary compressor, thereby greatly reducing the manufacturing cost.

The variable displacement rotary compressor according to the present invention can be evenly applied to a refrigerating device such as a home or industrial air conditioner.

1 is a schematic diagram showing a refrigeration cycle including a variable displacement rotary compressor of the present invention;

Figure 2 is a longitudinal cross-sectional view showing the interior of the rotary compressor according to Figure 1 longitudinally around the vane,

3 is a longitudinal sectional view showing the inside of the rotary compressor according to FIG.

4 is a perspective view of the compression part of the rotary compressor shown in FIG.

Figure 5 is a cross-sectional view shown for explaining the proper position of the suction port in the rotary compressor according to FIG.

6 is a cross-sectional view shown for explaining the second vane in the rotary compressor according to FIG.

FIG. 7 is a cross-sectional view illustrating a constraining flow path for restraining the second vane in the rotary compressor of FIG. 1.

8 is an enlarged perspective view illustrating the positions of the suction pipes and the respective connection pipes in the rotary compressor according to FIG. 1;

9 is a plan view shown to explain the welding position of the suction pipe and each connection pipe in the rotary compressor according to FIG.

10 and 11 are a longitudinal cross-sectional view and a cross-sectional view showing a power operation mode of the rotary compressor according to FIG.

12 and 13 are a longitudinal cross-sectional view and a cross-sectional view showing a saving operation mode of the rotary compressor according to FIG.

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

100: casing 130: intermediate bearing

131: communication hole 140: gas suction pipe

310: first cylinder 312: first suction port

320: first rolling piston 330: first vane

410: second cylinder 412: second suction port

413: vane chamber 414, 415: restraint euro

510: low pressure side connector 520: high pressure side connector

530: common side connecting pipe 540, 550: mode switching valve

Claims (14)

A casing in which the inner space is sealed; A plurality of cylinders installed on upper and lower sides of the inner space of the casing, each of the compression spaces formed independently of each other, and each of the suction ports communicating with each other so as to communicate with each of the compression spaces; A suction pipe configured to distribute the refrigerant to the suction ports of the plurality of cylinders; A plurality of rolling pistons compressing the refrigerant while pivoting in the compression spaces of the cylinders; A plurality of vanes for separating the compression spaces of the cylinders into the suction space and the discharge space together with the rolling pistons; And And a vane confinement unit configured to change an operation mode of the compressor by restraining or releasing vanes of at least one of the vanes. The suction pipe is a variable displacement rotary compressor coupled to the inlet of the first cylinder located above the plurality of cylinders. The method of claim 1, Among the vanes, a vane provided in the second cylinder to which the suction pipe is not coupled is formed at one side thereof with a sealing surface in contact with the rolling piston, and the opposite side of the sealing surface is pressurized by the pressure. A variable displacement rotary compressor having a pressure surface formed thereon. The method of claim 2, And a chamber in which the vane pressurization surface side of the second cylinder is separated from the inner space of the casing and filled with a refrigerant of suction pressure or discharge pressure. The method of claim 2, And a mode switching unit configured to selectively supply a suction pressure or a discharge pressure refrigerant to the pressurized surface of the vane outside the casing. The method of claim 4, wherein The mode switching unit includes a mode switching valve for selecting a refrigerant of suction pressure or discharge pressure on the pressure surface of the vane, a suction pressure side connecting pipe connecting the first inlet and the suction pipe of the mode switching valve, and the mode switching valve. A variable pressure type rotary compressor comprising: a discharge pressure side connecting pipe connecting the second inlet of the casing and the inner space of the casing; and a common side connecting pipe connecting the outlet of the mode switching valve and the pressing surface of the vane. The method of claim 5, And at least one suction port of the cylinder in which the chamber is formed is formed such that the radial center line intersects the axial center of the cylinder having the suction port in planar projection. The method of claim 5, The distance L1 from the point A at which the suction pipe is connected to the casing to the point B at which the common side connecting pipe is connected to the casing is the point at which the discharge side connecting pipe is connected to the casing at point A. C) A variable displacement rotary compressor arranged no longer than the distance L2. The method of claim 5, And the suction pipe, the discharge pressure side connection pipe, and the common side connection pipe are welded to the casing. The method according to any one of claims 1 to 8, A variable displacement rotary compressor of the plurality of cylinders is provided with the vane confinement unit in a second cylinder to which the suction pipe is not coupled. The method of claim 9, The vane confinement unit is a variable displacement rotary compressor for constraining the vane by using the pressure of the inner space of the casing. The method of claim 10, The second cylinder is in communication with the vane slot to allow the vane to move in a radial direction, penetrates in a direction substantially perpendicular to the direction of movement of the vane moving in the vane slot, at least to communicate with the inner space of the casing A variable displacement rotary compressor having one first restriction hole formed therein. The method of claim 11, And a second restriction hole formed in the second cylinder so as to communicate with a suction port of the second cylinder on the opposite side of the first restriction hole about the vane slot thereof. The method of claim 1, And a second cylinder to which the suction pipe is not coupled is disposed below the first cylinder, and the suction port of the second cylinder is formed to be inclined toward an inner circumferential surface at one corner of the second cylinder. The method of claim 13, An intermediate bearing for separating each compression space is disposed between the first cylinder and the second cylinder, and the intermediate bearing has a communication hole for communicating the inlet port of the first cylinder and the inlet port of the second cylinder is formed. compressor.

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