KR101324373B1 - Multi-cylinder rotary compressor and refrigeration cycle device - Google Patents

Abstract

The present invention relates to a multi-cylinder rotary compressor and a refrigeration cycle device, wherein the multi-cylinder rotary compressor (R) includes cylinders (6A, 6B) through an intermediate partition plate (2), and introduces a cylinder chamber into which low pressure gas is introduced. The blade chambers 10a and 10b communicate with Sa and Sb through blade grooves, and the spring member 14 is provided in the first blade chamber to provide back pressure to the blade 11a so that a compression action is always performed in the cylinder chamber. The second blade exhaust chamber has a sealed structure, and the pressure switching mechanism K for guiding the high pressure gas to perform the compression action in the cylinder chamber and guiding the low pressure gas to perform the operation of closing the oil collecting part 15 The pipe length L [m] from the pressure switching mechanism to the blade exhaust chamber is provided upward, and the maximum rotation speed of the compressor is "Fmax [Hz]", and the sound velocity of the discharged high pressure gas is "C [m / s]. L <C / 4Fmax (Equation 1) holds. The present invention provides a multi-cylinder rotary compressor which prevents the occurrence of an abnormal increase in vibration force or abnormal increase in blade exhaust pressure fluctuation due to resonance, and improves reliability and high compression performance. A refrigeration cycle device capable of improving the refrigeration cycle efficiency is provided.

Description

Multi-cylinder rotary compressors and refrigeration cycle units {MULTI-CYLINDER ROTARY COMPRESSOR AND REFRIGERATION CYCLE DEVICE}

The present invention relates to a multi-cylinder rotary compressor capable of switching compression capacity, and a refrigeration cycle apparatus comprising the multi-cylinder rotary compressor to form a refrigeration cycle.

In a refrigeration cycle apparatus, many-cylinder rotary compressors provided with a plurality of (mainly two) cylinder chambers in a compression mechanism unit are frequently used. In this type of compressor, switching of so-called full-capacity operation and half-capacity operation, in which a plurality of cylinder chambers simultaneously perform a compression action or stop a compression action in only one cylinder chamber, reduces compression work. It is advantageous if possible.

The multi-cylinder compressor disclosed in Japanese Laid-Open Patent Publication No. 2006-22766 has a first cylinder and a second cylinder, and includes a first roller and a second roller that eccentrically rotate within each cylinder, and the cylinders are in contact with the rollers. The 1st vane (blade) and the 2nd vane (blade) which divide an inside into a low pressure chamber and a high pressure chamber are provided, and a back pressure is applied by only a 1st vane spring member.

Back pressure is applied to the second vane through the back pressure passage, and when the low pressure (suction pressure) is guided to the back pressure passage, the inside of the second cylinder is low pressure, so no differential pressure is generated at the front end and the rear end of the vane. . That is, it becomes the half-capacity operation | operation which performs the closing operation which does not perform a compression operation in a 2nd cylinder, and performs a compression operation only in a 1st cylinder.

When the high pressure (discharge pressure) is guided to the back pressure passage, since the inside of the second cylinder is low pressure, a differential pressure is generated at the front end and the rear end of the second vane, and the vane is pressed to apply the force. Therefore, a full compressor operation capable of performing a compression operation in both cylinder chambers can be performed, and a preferred compressor that satisfies the above-described requirements is provided.

In the above-described multi-cylinder compressor, since the pipe is used as the back pressure passage, the fluid in the pipe reciprocates in accordance with the reciprocating movement of the second vane, and when the number of vibrations coincides with the natural frequency of the pipe, the pipe by resonance There is a possibility that an abnormal increase in the vibration force against the air or an abnormal increase in the pressure fluctuation of the vane exhaust may occur.

Further, Japanese Laid-Open Patent Publication No. 2006-22766 is characterized in that the cross-sectional area of the back pressure passage is made equal to or more than the average value of the surface area of the second vane exposed into the second cylinder. As a result, it is possible to sufficiently secure the back pressure passage, to reduce the pressure pulsation generated by the force application of the second vane, and to reduce the pressure fluctuation of the refrigerant applied as the back pressure.

However, in practice, the cross-sectional area of the back pressure passage based on the above conditions becomes a very large diameter, resulting in an enlargement of the compressor. In addition, no reference is made here to the relationship between the frequency of the fluid in the pipe and the natural frequency of the pipe.

The present invention has been made on the basis of the above circumstances, and an object thereof is to provide a second cylinder with a variable compression capacity, and to provide a path from the frequency and pressure switching means of the blade reciprocating motion to the blade exhaust chamber. A multi-cylinder rotary compressor which achieves improved reliability and high compression performance by eliminating the coincidence of natural vibrations and preventing occurrence of abnormal increase in vibration force or abnormal increase in blade exhaust pressure due to resonance. It is to provide a refrigeration cycle apparatus that can be provided with a cylindrical rotary compressor to improve the refrigeration cycle efficiency.

In order to satisfy the above object, the multi-cylinder rotary compressor of the present invention accommodates an electric motor portion and a compression mechanism portion in a hermetic container, and the inner bottom of the hermetic container is an oil collecting part for collecting lubricating oil.

The compression mechanism unit includes a first cylinder and a second cylinder via an intermediate partition plate, forms a cylinder chamber for introducing low pressure gas into the inner diameter portion of each cylinder, and communicates with these cylinder chambers through a blade groove. The blade compartment is installed.

The rotary shaft connected to the electric motor unit includes an eccentric portion accommodated in each cylinder chamber, and the eccentric moving roller is fitted in the eccentric portion in accordance with the rotation of the rotary shaft, and the blade tip portion is in contact with the roller circumferential wall. Partition the cylinder chamber.

Either of the blade compartments provided in the first cylinder and the second cylinder imparts elastic force to the rear end of the blade so that the blade front end is in contact with the roller circumferential wall, and always compresses in the cylinder chamber in accordance with the rotation of the rotating shaft. An elastic body is provided.

The other blade compartment forms a sealed structure, and guides a portion of the high pressure gas to the blade compartment, imparting a high pressure back pressure to the rear end of the blade, and contacting the blade front end with the roller circumferential wall to compress the cylinder chamber according to the rotation of the rotating shaft. Or a pressure switching means for guiding a portion of the low pressure gas introduced into the cylinder chamber to impart a low pressure back pressure to the blade rear end to keep the blade tip away from the roller circumferential wall.

The height direction position of the pressure switching means is located above the oil level of the lubricating oil of the oil collecting part, and the length of the pipe line L [m] from the pressure switching means to the blade exhaust chamber is the maximum rotational speed of the compressor "Fmax [Hz]". When the sound velocity of the high pressure gas discharged from the sealed container is "C [m / s]", the following equation 1 holds.

In order to satisfy the above object, the refrigeration cycle apparatus of the present invention comprises a multi-cylinder rotary compressor, a condenser, an expansion device, and an evaporator described above to constitute a refrigeration cycle.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic longitudinal sectional view of a multicylinder rotary compressor according to a first embodiment of the present invention, and a refrigeration cycle configuration diagram of a refrigeration cycle apparatus.
2 is a schematic longitudinal sectional view of a multi-cylinder rotary compressor according to a second embodiment of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described based on drawing.

FIG. 1: is a figure which shows the schematic sectional structure of the multicylinder rotary compressor R of 1st Embodiment, and the refrigeration cycle structure of the refrigerating cycle apparatus provided with the said multicylinder rotary compressor R. In FIG. (In addition, in order to eliminate the trouble of drawing, there are some parts which are described but not indicated.

First, referring to the multi-cylinder rotary compressor R, reference numeral 1 denotes a hermetically sealed container, and a lower portion of the hermetic container 1 has a first compression mechanism part 3A and an intermediate partition plate 2 formed therein. 2 compression mechanism part 3B is provided, and the electric motor part 4 is provided in the upper part. These 1st compression mechanism parts 3A and 2nd compression mechanism parts 3B are connected to the electric motor part 4 via the rotating shaft 5.

The 1st compression mechanism part 3A is equipped with the 1st cylinder 6A, and the 2nd compression mechanism part 3B is provided with the 2nd cylinder 6B. The main bearing 7 is fixed to the upper surface of the first cylinder 6A, and the secondary bearing 8 is fixed to the lower surface of the second cylinder 6B. The rotary shaft 5 is integrally provided with a first eccentric portion Ga and a second eccentric portion Gb which penetrate the insides of the cylinders 6A and 6B and are formed with a phase difference of approximately 180 degrees.

Each of the eccentric portions Ga and Gb has the same diameter as each other and is assembled to be located in the inner diameter portion of each cylinder 6A, 6B. The first roller 9a is fitted to the circumferential surface of the first eccentric portion Ga, and the second roller 9b is fitted to the circumferential surface of the second eccentric portion Gb.

The first cylinder chamber Sa is formed in the inner diameter portion of the first cylinder 6A, and the second cylinder chamber Sb is formed in the inner diameter portion of the second cylinder 6B. Each of the cylinder chambers Sa and Sb is formed to have the same diameter and height dimension, and a portion of the circumferential wall of the rollers 9a and 9b is freely eccentrically rotated while linearly contacting a portion of the circumferential wall of the cylinder chambers Sa and Sb. Are accepted.

In the first cylinder 6A, a first blade chamber 10a communicating with the first cylinder chamber Sa through the blade groove is provided, and the first blade 11a is freely accommodated in the blade groove.

In the second cylinder 6B, a second blade chamber 10b communicating with the second cylinder chamber Sb and the blade groove is provided, and the second blade 11b is freely accommodated in the blade groove.

The front end portions of the first and second blades 11a and 11b are formed in a substantially arcuate shape in plan view, and can protrude into opposing cylinder chambers Sa and Sb. In this state, the tip portions of the blades 11a and 11b are in line contact with the peripheral walls of the circular first and second rollers 9a and 9b in plan view, irrespective of the rotation angle.

The first cylinder 6A is provided with a horizontal hole communicating with the first blade chamber 10a and the outer circumferential surface of the cylinder 6A, and a spring member 14 which is an elastic body is accommodated. The spring member 14 is interposed between the rear end surface of the first blade 11a and the inner circumferential wall of the hermetic container 1, and imparts elastic force (back pressure) to the blade 11a.

The second blade chamber 10b of the second cylinder 6B is provided at a position protruding outward from the circumferential end of the flange portion of the sub-bearing 8, and the upper and lower surfaces thereof are opened, and are opened into the sealed container 1 as it is. .

Here, the upper surface opening portion of the second blade compartment 10b is closed by the intermediate partition plate 2, and the lower surface opening is blocked by the flange portion of the secondary bearing 8 and the blocking plate 12. The blade compartment 10b forms a sealed structure.

The horizontal hole which connects the 2nd blade chamber 10b and the outer peripheral surface of the 2nd cylinder 6B is provided, and the permanent magnet 13 is attached. The permanent magnet 13 has a magnetic force for self-adsorption when the rear end of the second blade 11b contacts.

In this state, the distal end of the second blade 11b is immersed more than the circumferential wall of the second cylinder chamber Sb, and the distal end of the blade 11b is moved by the roller 9b even when the second roller 9b moves. It is located away from the circumferential wall of.

The pressure switch mechanism (pressure switch means) K mentioned later is connected to the 2nd blade exhaust chamber 10b of the 2nd cylinder 6B. According to the switching operation of this pressure switching mechanism K, a high pressure gas (discharge pressure) or a low pressure gas (suction pressure) can be selected and guide | induced to the 2nd blade exhaust chamber 10b, and the rear end part of the 2nd blade 11b is carried out. Perform a pressure switch of back pressure to.

An oil collecting part 15 for collecting lubricating oil is formed at the inner bottom of the sealed container 1. In Fig. 1, the solid line across the flange portion of the main bearing 7 represents the oil surface of the lubricating oil, and almost all of the first compression mechanism portion 3A and all of the second compression mechanism portion 3B are the oil collecting portion ( 15) is immersed in the lubricant.

Since the 2nd blade compartment 10b is a sealed structure, even if the 2nd blade 11b reciprocates, the lubricating oil of the oil collection part 15 will not intrude into the blade compartment 10b as it is. However, although the detailed description is omitted here, the lubrication property of the 2nd blade 11b is ensured by providing the oil supply structure with respect to the sliding contact surface of the 2nd blade 11b and the blade groove.

As the multi-cylinder rotary compressor R configured as described above, the discharge pipe P is connected to the upper end of the sealed container 1. The discharge pipe P is connected to the upper end of the accumulator 20 through the condenser 17, the expansion device 18, and the evaporator 19. The accumulator 20 and the multi-cylinder rotary compressor R are connected via a suction pipe Pa.

Although not shown, the said suction pipe Pa is connected to the circumferential end surface of the intermediate partition plate 2 through the sealed container 1 which comprises the multi-cylinder rotary compressor R. As shown in FIG. The intermediate partition plate 2 is provided with a suction guide path from the circumferential surface portion to which the suction pipe Pa is connected toward the axial center direction. The tip of this suction guide passage branches into two branched shapes, inclined upward and inclined downward.

The branch guide path branched upwardly inclined communicates with the first cylinder chamber Sa. The branch guide path branched downward is in communication with the second cylinder chamber Sb. Therefore, the accumulator 20 and the 1st cylinder chamber Sa and the 2nd cylinder chamber Sb of the multicylinder rotary compressor R are always in communication.

The refrigeration cycle apparatus is constructed by pipe-connecting the multicylinder rotary compressor R, the condenser 17, the expansion device 18, the evaporator 19, and the accumulator 20 which were demonstrated above in order.

Subsequently, the pressure switching mechanism K will be described in detail.

The connection hole penetrates the circumferential wall of the said airtight container 1, and is axially directed from the circumferential end surface of the 2nd cylinder 6B. This connection hole penetrates the permanent magnet 13 attached to the 2nd block chamber 10b, and communicates with the 2nd blade chamber 10b.

One end of the guide pipe (guide pipe) 26 is inserted into the connection hole provided in the sealed container 1 and the second cylinder 6B, and is fitted and fixed so that there is no liquid leakage. The guide pipe 26 is formed to stand upward along the side wall of the sealed container 1, and is a four-way switching valve (pressure switching valve) 27 which is installed at an upper position than the upper ends of the sealed container 1 and the accumulator 20. Is connected to the second port Gd.

A first branch pipe (high pressure pipe) 28 branched from the middle portion of the discharge pipe P communicating with the sealed container 1 and the condenser 17 to the first port Gc of the four-way switching valve 27. ) Is connected. The third port Ge is connected to a second branch pipe (low pressure pipe) 29 which communicates the evaporator 19 and the accumulator 20. The fourth port Gf is blocked by the plug 30.

As shown in FIG. 1, the valve body 31 accommodated in the four-way switching valve 27 and operated electronically has a position at which the third port Ge and the fourth port Gf communicate with each other, and a double-dashed line. As shown by the figure, it switches to the position which communicates the 2nd port Gd and the 3rd port Ge. In contrast, the first port Gc is always open, and the fourth port Gf is always closed by the plug 30.

Therefore, in the state of FIG. 1, the first port Gc and the second port Gd communicate with each other, and the third port Ge and the fourth port Gf communicate with each other by the valve body 31. However, since the fourth port Gf is blocked by the plug 30, only the communication between the first port Gc and the second port Gd remains.

When the valve body 31 moves to the position indicated by the double-dotted line in FIG. 1, the first port Gc and the fourth port Gf communicate with each other, and the valve body 31 causes the second port Gd and the first port to communicate with each other. Three ports Ge communicate. Similarly, since the fourth port Gf is blocked by the plug 30, only the communication between the second port Gd and the third port Ge remains.

In addition, although the four-way switching valve 27 used the standard goods used for the refrigeration cycle which comprises a normal heat pump type air conditioner, the same effect can be acquired even if it combines a plurality of switching valves by the four-way switching valve 27. Can be.

In the multi-cylinder rotary compressor (R) having the pressure switching mechanism (K) described above, and the refrigeration cycle apparatus including the compressor (R), the half-capacity operation by the action of the pressure switching mechanism (K) ) And switching between full power operation (normal operation) is possible.

When the half-capacity operation is selected, the valve body 31 of the four-way switching valve 27 constituting the pressure switching mechanism K is switched to the position indicated by the double-dotted line in FIG. Three ports Ge communicate. Accordingly, the evaporator 19 and the second branch pipe 29 communicate with the guide pipe 26 through the four-way switching valve 27 and also communicate with the second blade exhaust chamber 10B.

At the same time, a driving signal is sent to the electric motor unit 4, and the rotary shaft 5 is driven to rotate, and the first and second rollers 9a and 9b perform eccentric rotation in the respective cylinder chambers Sa and Sb. In the 1st cylinder 6A, the blade 11a is pressed by the spring member 14, and a force is applied, and the front-end part is sliding-contacted with the circumferential wall of the roller 9a, and divides into the inside of 1st cylinder chamber Sa.

The low pressure refrigerant gas is guided from the accumulator 20 to the suction pipe Pa, and is sucked and filled into the first cylinder chamber Sa and the second cylinder chamber Sb through the suction guide path and the branch guide path.

By the pressure switching mechanism K, a part of the low pressure refrigerant gas derived from the evaporator 19 is guided from the second branch pipe 29 to the guide pipe 26 through the four-way switching valve 27. Then, it is led from the guide tube 26 to the second blade chamber 10b and filled.

The front end of the second blade 11b facing the second cylinder chamber Sb is in a low pressure atmosphere, and the rear end of the second blade 11b facing the second blade chamber 10b is also in a low pressure atmosphere. The differential pressure does not occur at the front and rear ends of (11b).

When the second roller 9b is eccentrically moved in accordance with the rotation of the rotary shaft 5, the second blade 11b is different from the second roller 9b so that the rear end thereof contacts the permanent magnet 13 and is self-adsorbed as it is. It does not move. Therefore, the compression action is not performed in the second cylinder chamber Sb.

On the other hand, in the 1st cylinder chamber Sa, the 1st blade 11a receives the elastic force of the spring member 14, and the front-end part contacts the peripheral wall of the 1st roller 9a, and the 1st cylinder chamber Sa is divided into 2 parts. do. In accordance with the eccentric movement of the roller 9a, the volume of one compartment of the cylinder chamber Sa decreases, and the sucked gas is gradually compressed.

When the gas rises to a predetermined pressure, the discharge valve mechanism is opened, and once discharged to the discharge muffler, it is led into the sealed container 1 and filled. Then, the high pressure gas is led from the discharge pipe P to the condenser 17, liquefied to condense and turned into a liquid refrigerant. The liquid refrigerant is led to the expansion device 18, is adiabaticly expanded, evaporates in the evaporator 19, and takes the latent heat of evaporation from the air flowing through the evaporator 19 to freeze.

The low-pressure gas refrigerant evaporated in the evaporator 19 is led to the accumulator 20 to be gas-liquid separated, and the separated gas refrigerant is discharged from the accumulator 20 through the suction pipe Pa to the first cylinder chamber Sa and the second. Guided to the cylinder chamber Sb, the refrigeration cycle described above is constituted.

Since the compression action is not performed in the second cylinder chamber Sb, the operation is closed, the compression operation is carried out only in the first cylinder chamber Sa, and the half-capacity operation is performed.

When the electric power operation is selected, the valve body 31 of the four-way switching valve 27 moves to the solid line position shown in FIG. 1, and the first port Gc and the second port Gd communicate with each other. Therefore, the discharge pipe P and the first branch pipe 28 connected to the multi-cylinder rotary compressor R communicate with the guide pipe 26 via the four-way switching valve 27, and the second blade exhaust chamber ( 10b).

At the same time, a driving signal is sent to the electric motor unit 4, the rotary shaft 5 is driven to rotate, and the first and second rollers 9a and 9b perform eccentric rotation in the respective cylinder chambers Sa and Sb. do. In the first cylinder 6A, the blade 11a is pressed against the spring member 14, and a force is applied thereto, and the leading edge thereof is in sliding contact with the circumferential wall of the roller 9a, thereby dividing the inside of the first cylinder chamber Sa. .

The low pressure refrigerant gas is guided from the accumulator 20 to the suction pipe Pb, and is sucked and filled into the first cylinder chamber Sa and the second cylinder chamber Sb through the suction guide path and the branch guide path. In the first cylinder chamber Sa, a compression action is performed as described above, so that the high pressure gas is filled in the sealed container 1.

The high pressure refrigerant gas filled in the sealed container 1 is discharged to the discharge pipe P to circulate the above-mentioned refrigeration cycle, while a part of the high pressure gas flows from the first branch pipe 28 to the four-way switching valve 27. Is delivered. In accordance with the switching operation of the four-way switching valve 27, the high pressure gas is led to the guide tube 26, enters the sealed container 1, and is led to the second blade chamber 10b to be filled.

Although the distal end portion of the second blade 11b is in a low pressure atmosphere facing the second cylinder chamber Sb, but the rear end portion is in a high pressure atmosphere facing the second blade 11b, a differential pressure is generated at the distal end portion and the rear end portion. Since the rear end is a high pressure atmosphere, the blade 11b is pushed to the front end side and a force is applied.

When the second roller 9b is eccentrically moved in accordance with the rotation of the rotary shaft 5, the second blade compartment 10b is opened while the tip of the second blade 11b is in contact with the circumferential surface of the second roller 9b. Go back and forth. The second blade 11b bisects the second cylinder chamber Sb, and thus a compression action is performed.

In this way, the first cylinder chamber Sa and the second cylinder chamber Sb simultaneously perform compression operations to perform full power operation.

Moreover, the oil collection part 15 which collects lubricating oil is formed in the inner bottom part of the airtight container 1, and the 1st and 2nd compression mechanism parts 3A, 3B are immersed in lubricating oil. Naturally, the 2nd cylinder 6B is also in lubricating oil, and the 2nd blade chamber 10b provided here is also in the position immersed in lubricating oil.

On the other hand, the four-way switching valve (pressure switching mechanism K) 27 for selecting and guiding high pressure gas or low pressure gas to the second blade exhaust chamber 10b is a guide pipe 26 connected to the second blade exhaust chamber 10b. Except for the terminal portion of the), the oil collecting portion 15 is located above the lubricating oil surface. Therefore, the four-way switching valve 27 is not filled with lubricating oil, and there is no problem in operation.

And the pipeline length L [m] from the pressure switching mechanism K27 to the 2nd blade exhaust chamber 10b sets the maximum rotation speed of the compressor R from "Fmax [Hz], and the closed container 1. When the sound velocity of the high pressure gas discharged to the discharge pipe P is "C [m / s]", the following equation (1) is set.

(수학식 1)

(1)

In fact, the said pipe length L [m] is the total length of the guide pipe 26 which communicates the four-way switching valve 27 and 2nd blade chamber 10B which comprise the pressure switching mechanism K. As shown in FIG. More specifically, it protrudes from the one end surface of the guide pipe 26 inserted into the connection hole of the 2nd cylinder 6B to the exterior of the sealed container 1, and the 2nd port Gd of the four-way switching valve 27 is formed. Length to the other end connected to).

The second blade 11b reciprocates during the full-power operation, and the rear end protrudes into the second blade chamber 10b so that the fluid in the guide tube 26 reciprocates.

The guide tube 26 when the frequency according to the reciprocating motion of the fluid in the guide tube 26 and the natural frequency of the guide tube 26 communicating the second blade chamber 10b and the four-way switching valve 27 coincide with each other. This resonates. For this reason, there exists an abnormal increase of the vibration force to the piping (guide pipe 26), or the abnormal increase of the pressure fluctuation of the 2nd blade exhaust chamber 10b arises, and it leads to the fall of compression performance.

However, in general, when the maximum rotation speed Fmax of the compressor R is smaller than the resonance frequency C / 4L (Fmax <C / 4L), resonance of the guide pipe 26 serving as the pipe line does not occur. It is known. Therefore, the above equation is developed to obtain the equation (1).

By setting the length L of the pipe line (guide pipe 26) of the branch of the second blade chamber 10b from the four-way switching valve 27, Equation 1 is established, an abnormal increase in the vibration force for the pipe by resonance is achieved. B, it is possible to prevent the occurrence of an abnormal increase in the pressure fluctuation of the second blade exhaust chamber 10b, and to provide a highly reliable multi-cylinder rotary compressor R.

And in the refrigeration cycle apparatus provided with such a multicylinder rotary compressor R, the improvement of a refrigeration cycle efficiency can be obtained.

The sound velocity C of the high-pressure gas varies depending on the type, pressure, and temperature of the refrigerant, but the sound velocity C when the refrigerant is R410A, the discharge gas pressure of the refrigerant is 2.7 MPa, and the temperature is 64.3 ° C. Is 172 [m / s].

FIG. 2: is a figure which shows schematic sectional structure of the multicylinder rotary compressor R of 2nd Embodiment, and abbreviate | omits the refrigeration cycle structure of the refrigeration cycle apparatus shown in FIG. Since only the pressure switching mechanism Ka differs from FIG. 1, and all the components other than that are the same, the same component is attached | subjected and the new description is abbreviate | omitted.

The pressure switching mechanism Ka is configured to guide the first branch pipe 28 that guides the high pressure gas to the four-way switching valve 27 and the low pressure gas to the four-way switching valve 27 with respect to the four-way switching valve 27. The second branch pipe 29 and a guide pipe 26a for guiding the high and low pressure gas switched to the four-way switching valve 27 to the second blade exhaust chamber 10b are connected, and a predetermined portion of the guide pipe 26a is connected. It consists of a buffer (space volume) 32 installed in the.

Since the 1st branch pipe | tube 28 and the 2nd branch pipe | tube 29 are connected to the said four-way switching valve 27, the position becomes an upper part of the multi-cylinder rotary compressor R and the accumulator 20 inevitably. . On the other hand, the 2nd blade exhaust chamber 10b provided in the 2nd cylinder 6B is in the position near the bottom of the airtight container 1 substantially.

Therefore, the total length of the guide pipe 26 which communicates the 2nd blade exhaust chamber 10b and the four-way switching valve 27 becomes long, and switches pressure from the 2nd blade exhaust chamber 10b which is a condition of Formula (1) mentioned above. The pipe length L [m] to the mechanism K becomes long.

Therefore, the buffer 32 is provided in the guide pipe 26, and the distance from the 2nd blade chamber 10b to the buffer 32 can be set as the said pipe length L. FIG. The pipe length L is further shortened so that the frequency of the reciprocating motion of the blade 10b and the upper half of the natural frequency of the guide pipe 26a are increased, and the reduction in the vibration force of the guide pipe 26a can be obtained.

1 and 2, the inner diameter? D of the first branch pipe 28 leading the high pressure gas from the discharge pipe P to the four-way switching valve 27, and the four-way switching valve ( The inner diameter phi d of the guide tube 26 leading the high pressure gas or the low pressure gas from the 27 to the second blade exhaust chamber 10b is set such that Equation 2 below is satisfied based on the following conditions.

"V" is the exclusion volume [m 3] of the compressor R, and "ε" is the compression ratio at the time of operation. "Dd" is the tube diameter [m] of the discharge tube P, and "n" is the polytropic index of the refrigerant gas which is the working fluid. "Vo" is the variation volume (during one revolution) of the second blade chamber 10b, and is obtained by Vo = 4HBe [m 3].

"H" is the height dimension [m] of the second blade 11b, which is the side for the driving operation, and "B" is the width dimension [m], "e" of the second blade 11b, is the side for the driving operation. It is an eccentric amount of the eccentric part Gb of the rotating shaft 5 accommodated in 2nd cylinder chamber Sb.

To explain further, in general, when the exclusion volume of the compressor is " V ", the discharge volume Vd is represented by the following expression (3).

By the action of the second blade 11b in the above equation (3), the average velocity of the flow generated in the pipe connecting the second blade chamber (10b) and the discharge pressure portion is the ratio of the discharge gas flowing through the discharge pipe (P). If it is always going to be smaller than the average flow rate, it is necessary to satisfy the following expression (4).

By substituting Equation 3 into Equation 4, Equation 2 is obtained.

Since the above formula (2) is satisfied, the average velocity of the fluid generated in the guide tube 26 can always be made smaller than the average flow rate of the discharge gas flowing through the discharge tube P, so that the inside of the tube (guide tube 26) It is possible to provide a compressor R having a low fluid friction loss.

Moreover, since it solves without making a pipe diameter larger than necessary like the above-mentioned [patent document 1], the compact compressor R can be obtained.

In addition, this invention is not limited to embodiment mentioned above, In the implementation stage, a component can be modified and actualized in the range which does not deviate from the summary. And various invention can be formed by appropriate combination of the some component disclosed by embodiment mentioned above.

According to the present invention, a multi-cylinder rotary compressor capable of suppressing the occurrence of an abnormal increase in vibration force or an abnormal increase in blade exhaust pressure fluctuation due to resonance, thereby improving reliability and high compression performance, and the multi-cylinder The refrigeration cycle apparatus which can provide the rotary compressor and can aim at the improvement of a refrigeration cycle efficiency can be provided.

Claims (4)

An oil collecting part for accommodating the electric motor part and the compression mechanism part in the sealed container and collecting the lubricating oil at the inner bottom of the sealed container;
The compression mechanism unit,
A first cylinder and a second cylinder, which are provided via an intermediate partition plate, are formed with cylinder chambers through which low pressure gas is introduced into respective inner diameter portions, and blade chambers communicating with blade grooves in these cylinder chambers;
A rotating shaft having an eccentric portion accommodated in each cylinder chamber of the first cylinder and the second cylinder, and connected to the electric motor portion;
A roller fitted to an eccentric portion of the rotary shaft and eccentrically moved in the cylinder chamber according to the rotation of the rotary shaft, and
A blade which is freely received in the blade groove and partitions the cylinder chamber in a state in which the tip portion contacts the roller circumferential wall,
Either of the blade exhaust chambers provided in the first cylinder and the second cylinder imparts elastic force to the rear end of the blade to contact the blade front end with the roller circumferential wall, and always compresses in the cylinder chamber as the rotation shaft rotates. Equipped with an elastic body to make
The other side of the blade compartment forms a sealed structure,
The high pressure gas is guided to the blade exhaust chamber forming the airtight structure to give a high pressure back pressure to the rear end of the blade to contact the blade front end with the roller circumferential wall to perform a compression action in the cylinder chamber, or to guide the low pressure gas to the after blade. A pressure switching means for applying a low pressure back pressure to the end to keep the blade tip away from the roller circumferential wall;
The height direction position of the said pressure switching means is located above the lubricating oil surface of the said oil collecting part, and the pipe length L [m] to the pressure switching means and the said blade exhaust chamber is the maximum rotation speed of a compressor "Fmax [Hz]. ] ", When the sound velocity of the high pressure gas discharged from the said airtight container is" C [m / s] ", the following formula (1) is established.

(1) The method of claim 1,
The pressure switching means includes a pressure switch valve connected to a high pressure pipe through which high pressure gas is guided, a low pressure pipe through which low pressure gas is guided, and a guide pipe leading to high pressure gas or low pressure gas into the blade chamber, and a space provided in the guide pipe. With volume,
The length L of the guide pipe to the blade compartment and the space volume is set to the length L of the pipe to the pressure switching means and the blade compartment of the equation (1). 3. The method according to claim 1 or 2,
The inner diameter φd of the pipe leading the high pressure gas to the pressure switching means and the inner diameter φd of the pipe leading the high pressure gas or the low pressure gas from the pressure switching means to the blade exhaust chamber are based on the following conditions. A multi-cylinder rotary compressor characterized by the following equation (2).
(2)

V: exclusion volume of the compressor [m 3], ε: compression ratio during operation,
Dd is the discharge tube diameter [m] of the cycle, n is the polytrough index of the working fluid,
Vo: blade exhaust fluctuation volume (in one revolution) Vo = 4HBe [㎥].
(H: height of the blade on the closing side [m], B: width of the blade on the closing side [m], e: eccentricity of the rotating shaft eccentric on the closing side) A refrigeration cycle device comprising the multicylinder rotary compressor, condenser, expansion device and evaporator of claim 1 or 2 to constitute a refrigeration cycle.

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