JP2011144800A - Multi-cylinder rotary compressor and refrigerating cycle device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multi-cylinder rotary compressor in which a bearing is reduced in size to reduce the cost of parts and which enables improvement in manufacturability and processing precision, and a refrigerating cycle device provided with the multi-cylinder rotary compressor and adapted to improve refrigerating cycle efficiency. <P>SOLUTION: The multi-cylinder rotary compressor C is provided with a first cylinder 6A and a second cylinder 6B as a compression mechanism part 3 through the medium of an intermediate partition board 2, and formed with cylinder chambers Sa, Sb which introduce low-pressure gas into the inner diameter parts of them. Blade back chambers 11a, 11b are provided to each of the cylinder chambers respectively through the medium of the blade grooves 10a, 10b which house the blades 12a, 12b so that they can move freely, and the first blade back chamber is provided with a spring member 13 which gives elastic force to the rear end of the blade and which brings the tip of the blade into contact with the roller 9a peripheral wall. The second blade back chamber is provided with a guide passage 17 which can be blocked by a blocking member 15 which is a different part from a sub-bearing 7B and by the intermediate partition board, and to which piping 16 for pressure control is connected to supply pressure by switching between high pressure and low pressure to the blocking member 15 so as to provide communication with the second blade back chamber. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

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

  In the refrigeration cycle apparatus, a multi-cylinder rotary compressor having a plurality of (mainly two) cylinder chambers in the compression mechanism is frequently used. In this type of compressor, a full capacity operation in which the compression action is simultaneously performed in a plurality of cylinder chambers, and a half capacity operation in which the compression action is stopped in one cylinder chamber and the compression action is stopped on the other to reduce the compression work. It is advantageous if it can be switched.

  A multi-cylinder compressor (a variable displacement rotary compressor) disclosed in [Patent Document 1] includes a roller (rolling piston) that rotates eccentrically in a cylinder, and a suction chamber (suction chamber) that contacts the roller and sucks the cylinder chamber. A blade (vane) that divides into a compression chamber and a blade back chamber (vane pressure chamber) behind the blade. By supplying discharge pressure or suction pressure to the blade back chamber, the operation of the blade is restricted or released. The pressure control unit is configured.

  When suction pressure (low pressure) is guided to the blade back chamber, the pressure inside the cylinder is low, so that no differential pressure is generated between the front end portion and the rear end portion of the blade. Therefore, the compression operation is not performed in the cylinder chamber. When the discharge pressure (high pressure) is guided to the blade back chamber, the tip end portion of the blade becomes low pressure and the rear end portion becomes high pressure, a force due to the differential pressure is generated in the blade, and the blade is urged against the roller. Therefore, the compression operation is performed in the cylinder chamber.

Special table 2008-524515

By the way, in the above-mentioned [Patent Document 1], the pressure of the blade back chamber is obtained by fastening the upper intermediate partition plate (intermediate bearing) and the lower auxiliary bearing (bearing) to the lower cylinder. A pressure leakage prevention fastening unit for preventing leakage is provided.
Specifically, the intermediate partition plate and the sub-bearing are formed in a disc-shaped body larger than the inner diameter of the cylinder and smaller than the outer diameter, and a semicircular shape extending from one side of the body to provide a blade back chamber. And an extension portion for closing (covering). By fastening the extension part and the cylinder with a partial fastening bolt, pressure leakage from the blade back chamber is prevented.

  However, the intermediate partition plate and the bearing have the deformed outer shape as described above, and it takes time to manufacture. The inner diameter hole of the intermediate partition plate need only have a diameter that allows the eccentric part of the rotating shaft into which the roller is fitted during assembly to pass therethrough, so that machining accuracy is not necessary, but the bearing of the bearing that pivotally supports a part of the rotating shaft. The inner diameter hole needs to pivot the rotating shaft so that there is no runout, and requires high machining accuracy.

  Particularly, when machining the inner diameter hole of the bearing, since it is a deformed outer shape, it is difficult to fix the chuck for accurate centering, and rotational imbalance occurs and the finished dimensional accuracy deteriorates. If the outer shape of the bearing is extended to the apex of the extended portion and made into a simple circular shape, the above-mentioned adverse conditions can be eliminated. However, on the other hand, there is a problem that the material costs are increased and the weight is increased.

  The present invention has been made on the basis of the above circumstances, and the object of the present invention is to reduce the cost of parts by reducing the size of the bearing, and to improve the manufacturability and machining accuracy on the premise that the compression capacity is variable with a plurality of cylinders. It is an object of the present invention to provide a multi-cylinder rotary compressor that can improve the efficiency of the refrigeration cycle, and a refrigeration cycle apparatus that includes this multi-cylinder rotary compressor and can improve the refrigeration cycle efficiency.

In order to satisfy the above object, a multi-cylinder rotary compressor of the present invention accommodates an electric motor section and a compression mechanism section that are connected to each other through a rotating shaft in a sealed case.
The compression mechanism section includes a first cylinder and a second cylinder with an intermediate partition plate interposed therebetween, and forms cylinder chambers for introducing low-pressure gas into the inner diameter portions of these cylinders. And provide a blade back chamber.
The rotating shaft has an eccentric portion accommodated in each cylinder chamber, and a roller that rotates eccentrically in the cylinder chamber as the rotating shaft rotates is fitted to the eccentric portion, and the blade is accommodated in the blade groove so as to be movable. To do. The tip of the blade divides the cylinder chamber into two chambers in a state of being in contact with the roller peripheral wall.
One of the blade back chambers in the first cylinder and the second cylinder includes an elastic body that applies an elastic force to the rear end portion of the blade and causes the blade front end portion to contact the roller peripheral wall. One of the other blade back chambers is attached to the bearing-side end face of the cylinder, and is closed by a closing member and an intermediate partition plate which are separate parts from the bearing.
A pressure control pipe for switching between high pressure and low pressure is connected to the closing member, and a guide passage is provided for communicating the pressure control pipe with the blade back chamber.
In order to satisfy the above object, a refrigeration cycle apparatus of the present invention comprises the above-described multi-cylinder rotary compressor, a condenser, an expansion device, and an evaporator to constitute a refrigeration cycle.

  According to the present invention, a multi-cylinder rotary compressor capable of reducing component costs by reducing the size of the bearing and improving manufacturability and processing accuracy, and a refrigeration cycle efficiency provided with the multi-cylinder rotary compressor are provided. A refrigeration cycle apparatus that can improve the quality of the apparatus can be provided.

1 is a schematic longitudinal sectional view of a multi-cylinder rotary compressor according to a first embodiment of the present invention and a refrigeration cycle configuration diagram of a refrigeration cycle apparatus. The disassembled perspective view of the principal part of the multi-cylinder rotary compressor based on the first embodiment. The A arrow directional view in FIG. 1 based on the 1st Embodiment. The side view which abbreviate | omitted some multicylinder rotary compressors and the accumulator based on the 1st Embodiment. The side view which abbreviate | omitted a part of multi-cylinder rotary compressor and the accumulator based on 2nd Embodiment in this invention. The figure explaining the accommodation amount of the lubricating oil in the multicylinder rotary type compressor based on 3rd Embodiment in this invention. The figure explaining the accommodation amount of the lubricating oil in the multicylinder rotary type compressor based on 4th Embodiment in this invention. The figure which abbreviate | omitted one part of the multicylinder rotary type compressor of a mutually different structure based on 5th Embodiment in this invention. The longitudinal cross-sectional view which expanded the compression mechanism part in the multicylinder rotary compressor based on 6th Embodiment in this invention. The figure showing the examination result of the crack phenomenon of a discharge valve from the characteristic of the differential pressure with respect to the number of rotations in the multi-cylinder rotary compressor concerning the embodiment of the present invention. The characteristic view of the eccentric part sliding loss with respect to the eccentric part sliding length / eccentric part axial diameter based on Embodiment of this invention. The characteristic figure of the total efficiency with respect to eccentric part sliding length / eccentric part axial diameter based on embodiment of this invention. The figure which abbreviate | omitted a part of multi-cylinder rotary type compressor based on 7th Embodiment in this invention. It is a schematic refrigeration cycle block diagram of the refrigerating cycle device concerning an embodiment of the invention, and a refrigerating cycle at the time of selecting full capacity operation and a refrigerating cycle at the time of selecting half capacity operation. The schematic block diagram of the multicylinder rotary compressor which abbreviate | omitted the refrigerating cycle based on 8th Embodiment in this invention. The schematic block diagram of the multicylinder rotary type compressor which abbreviate | omitted the refrigerating cycle based on the modification of the said 8th Embodiment. The figure which demonstrates schematically the mutually different insertion position of the piping for pressure control with respect to the airtight case and the 1st, 2nd suction pipe based on the said 8th Embodiment. The figure which illustrates schematically the mutually different insertion position of the piping for pressure control with respect to the airtight case, and the 1st, 2nd suction pipe based on the modification of the said 8th Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram illustrating a schematic cross-sectional structure of a multi-cylinder rotary compressor C and a refrigeration cycle configuration of a refrigeration cycle apparatus R including the multi-cylinder rotary compressor C according to the first embodiment. .

First, the multi-cylinder rotary compressor C will be described. Reference numeral 1 denotes a sealed case. A compression mechanism 3 is provided in the lower part of the sealed case 1, and an electric motor part 4 is provided in the upper part. The electric motor unit 4 and the compression mechanism unit 3 are integrally connected via a rotating shaft 5.
The compression mechanism unit 3 includes a first cylinder 6A on the upper side and a second cylinder 6B on the lower side. The main bearing 7A is attached and fixed to the upper end surface of the first cylinder 6A, and the auxiliary bearing 7B is attached and fixed to the lower end surface of the second cylinder 6B. An intermediate partition plate 2 is interposed between the first cylinder 6A and the second cylinder 6B.

  The rotating shaft 5 penetrates through the cylinders 6A and 6B, and integrally includes a first eccentric portion a and a second eccentric portion b having the same diameter and a phase difference of about 180 °. Each eccentric part a and b is assembled so that it may be located in the internal diameter part of each cylinder 6A, 6B. The first roller 9a is fitted to the circumferential surface of the first eccentric part a, and the second roller 9b is fitted to the circumferential surface of the second eccentric part b.

The inner diameter portion of the first cylinder 6A is covered with the main bearing 7A and the intermediate partition plate 2 to form a first cylinder chamber Sa. The inner diameter portion of the second cylinder 6B is covered with the intermediate partition plate 2 and the auxiliary bearing 7B, and a second cylinder chamber Sb is formed.
The first cylinder chamber Sa and the second cylinder chamber Sb are formed to have the same diameter and height. The rollers 9a and 9b are respectively accommodated in the cylinder chambers Sa and Sb so that the peripheral walls of the rollers 9a and 9b can be eccentrically rotated while being in line contact with the peripheral walls of the cylinder chambers Sa and Sb. .

  Double discharge mufflers 8a are attached to the main bearing 7A and cover the discharge valve mechanism provided on the main bearing 7A. Each discharge muffler 8a is provided with a discharge hole d. A single discharge muffler 8b is attached to the auxiliary bearing 7B, and covers the discharge valve mechanism provided in the auxiliary bearing 7B. The discharge muffler 8b is not provided with a discharge hole.

  The discharge valve mechanism provided in the main bearing 7A is opposed to the first cylinder chamber Sa, and is opened when the chamber pressure reaches a predetermined pressure due to the compression action, and discharges gas into the discharge muffler 8a. The discharge valve mechanism provided in the sub-bearing 7B faces the second cylinder chamber Sb and opens when the chamber pressure reaches a predetermined pressure, and discharges gas into the discharge muffler 8b.

A discharge gas guide path is provided across the auxiliary bearing 7B, the second cylinder 6B, the intermediate partition plate 2, the first cylinder 6A and the main bearing 7A. The discharge gas guide path guides the high-pressure gas discharged from the second cylinder chamber Sb to the lower discharge muffler 8b through the discharge valve mechanism into the upper double discharge muffler 8a.
An oil reservoir 14 for collecting lubricating oil is formed at the inner bottom of the sealed case 1. In FIG. 1, the solid line across the flange portion of the main bearing 7 </ b> A indicates the oil level of the lubricating oil, and almost all of the compression mechanism portion 3 is immersed in the lubricating oil in the oil reservoir 14.

FIG. 2 is an exploded perspective view showing a part of the compression mechanism section 3 according to the first embodiment. Only the main part is shown, and details are omitted.
The first cylinder 6A is provided with a first blade back chamber 11a communicating with the first cylinder chamber Sa via a blade groove 10a. The first blade 12a is movably accommodated in the blade groove 10a. Is done.

The second cylinder 6B is provided with a second blade back chamber 11b communicating with the second cylinder chamber Sb via the blade groove 10b, and the second blade 12b is movably accommodated in the blade groove 10b. Is done.
The leading ends of the first and second blades 12a and 12b are formed in a substantially arc shape in plan view, and can project and retract into the opposing cylinder chambers Sa and Sb. The rear end portions of the blades 12a and 12b are dimensioned so that they can project and retract into the opposing blade back chambers 11a and 11b.

With the tips of the blades 12a and 12b protruding into the opposing cylinder chambers Sa and Sb, the tips of the blades 12a and 12b are circularly connected to the circumferential walls of the first and second rollers 9a and 9b in a plan view regardless of the rotation angle. Contact.
The first cylinder 6A is provided with a lateral hole f that communicates the first blade back chamber 11a and the outer peripheral surface of the cylinder 6A, and accommodates a spring member 13 that is an elastic body. The spring member 13 is interposed between the rear end face of the first blade 12a and the inner peripheral wall of the sealed case 1, and applies an elastic force (back pressure) to the first blade 12a.

FIG. 3 is a view taken in the direction of arrow A in FIG. 1 and is also a bottom view of a part of the second cylinder 6B.
The second blade back chamber 11b in the second cylinder 6B is provided at a position protruding outward from the peripheral edge of the flange portion of the sub-bearing 7B, and the upper and lower surfaces are opened and opened in the sealed case 1 as they are.

However, the upper opening of the second blade back chamber 11b is covered by the intermediate partition plate 2 attached to the upper end surface of the second cylinder as shown in FIG. 1, and the lower opening is shown in FIGS. It is covered with the closing member 15 shown. Accordingly, the upper and lower opening portions of the second blade back chamber 11b are closed by the intermediate partition plate 2 and the closing member 15, thereby forming a sealed structure.
The closing member 15 is made of cast iron material, or is made of SMF3 type (iron-carbon sintered alloy) or SMF4 type (iron-carbon-copper sintered alloy), both of which are complicated. A material that can reliably manufacture the internal structure by molding is selected.

In particular, as shown in FIG. 3, the side end surface of the closing member 15 is formed along the peripheral end surface of the flange portion of the sub-bearing 7B, and a part of the side end surface facing this side end surface protrudes, and the pressure control pipe 16 is connected. Further, the closing member 15 is provided with a guide passage 17 from the connection portion of the pressure control pipe 16 to the second blade back chamber 11b.
In other words, the second blade back chamber 11 b has a sealed structure by the intermediate partition plate 2 and the closing member 15, but communicates with the pressure control pipe 16 through the guide passage 17 of the closing member 15.

  The pressure control pipe 16 constitutes a part of a blade back pressure control mechanism K described later. The blade back pressure control mechanism K selects and guides the high pressure gas (discharge pressure) or the low pressure gas (suction pressure) to the second blade back chamber 11b, and the pressure of the back pressure on the rear end portion of the second blade 12b. It controls switching.

As shown in FIG. 1 again, a discharge pipe P is connected to the upper end of the sealed case 1 constituting the multi-cylinder rotary compressor C. The discharge pipe P is connected to an evaporator 22 via a condenser 20 and an expansion device 21. A suction pipe Pa is connected to the evaporator 22, and the suction pipe Pa is connected to a multi-cylinder rotary compressor C via an accumulator 23.
That is, the refrigeration cycle apparatus R is configured by connecting the multi-cylinder rotary compressor C, the condenser 20, the expansion device 21, the evaporator 22, and the accumulator 23 described above in order.

  In the multi-cylinder rotary compressor C, the suction pipe Pa penetrates the sealed case 1 and is connected to the peripheral end surface of the intermediate partition plate 2. In the intermediate partition plate 2, a suction guide path 25 is provided in the axial direction from the peripheral surface portion to which the suction pipe Pa is connected. The tip of the suction guide path 25 is bifurcated into a diagonally upward and diagonally downward direction.

  The branch guide path branched obliquely upward communicates with the first cylinder chamber Sa. The branch guide path branched obliquely downward communicates with the second cylinder chamber Sb. Therefore, the accumulator 23 and the first cylinder chamber Sa and the second cylinder chamber Sb in the multi-cylinder rotary compressor C are always in communication.

Next, the blade back pressure control mechanism K will be described in detail.
The pressure control pipe 16 connected to the guide passage 17 of the closing member 15 penetrates the peripheral wall of the sealed case 1 and rises along the side wall of the sealed case 1. The insertion position of the pressure control pipe 16 with respect to the sealed case 1 and the insertion position of the suction pipe Pa extending from the accumulator 23 with respect to the sealed case 1 are set as follows.

FIG. 4 is a diagram for explaining a penetration position of the pressure control pipe 16 and the suction pipe Pa with respect to the sealed case 1 according to the first embodiment.
The airtight case 1 has a circular shape in plan view, and the pressure control pipe 16 and the suction pipe Pa are inserted in a state where they are aligned at the same axial position in the circumferential direction.

  That is, since the suction pipe Pa is connected to the intermediate partition plate 2 and the pressure control pipe 16 is connected to the closing member 15 attached to the lower end surface of the second cylinder 6B, the insertion portion g of the pressure control pipe 16 is There is an insertion portion h for the suction pipe Pa at the lower portion. In any of the insertion portions g and h, brazing is performed so that there is no liquid leakage or gas leakage.

  The diameter of the pressure control pipe 16 is smaller than the diameter of the suction pipe Pa and is smaller than the diameter of the accumulator 23. If the pressure control pipe 16 protruding from the sealed case 1 rises at that position, the pressure control pipe 16 comes into contact with the suction pipe Pa or the accumulator 23. Moreover, if it extends greatly so that it may remove | deviate from the accumulator 23, it looks bad and material cost starts.

Therefore, as shown in FIG. 4, the pressure control pipe 16 is bent obliquely so as to avoid contact between the suction pipe Pa and the accumulator 23 at a position immediately after protruding from the sealed case 1. The pressure control pipe 16 extends to the upper part while contacting the side wall surface of the accumulator 23.
As shown in FIG. 1, a mounting bracket 26 is provided at a contact portion of the pressure control pipe 16 with the side wall surface of the accumulator 23, and fixedly supports a substantially middle portion in the vertical direction of the pressure control pipe 16. .

  As shown in FIG. 1 again, the upper end of the pressure control pipe 16 is connected to a pressure switching valve (pressure switching means) 27 provided at a position higher than the upper ends of the hermetic case 1 and the accumulator 23. The pressure switching valve 27 uses a four-way switching valve used in an air conditioner equipped with a heat pump refrigeration cycle capable of switching between cooling and heating operations, thereby reducing costs.

  Connected to the first port pa of the pressure switching valve 27 is a first branch pipe (high-pressure pipe) 28 branched from a discharge pipe P that communicates the sealed case 1 and the condenser 20, and is connected to the second port pb. The pressure control pipe 16 is connected to the third port pc, and a second branch pipe (low pressure pipe) 29 branched from the suction pipe Pa communicating the evaporator 22 and the accumulator 23 is connected to the third port pc.

  The fourth port pd is closed by the plug 30. The valve body 31 accommodated therein includes a position where the third port pc and the fourth port pd communicate with each other as shown in the figure, and a second port pb and a third port pc as indicated by a dashed line. Are switched electromagnetically to a position where they communicate with each other. The first port pa is always open, and the fourth port pd is always closed.

  Therefore, in the state of FIG. 1, the first port pa and the second port pb communicate directly, and the third port pc and the fourth port pd communicate via the valve body 31. However, since the fourth port pd is blocked by the plug body 30, only communication between the first port pa and the second port pb remains.

  When the valve element 31 moves to the position indicated by the alternate long and short dash line in FIG. 1, the second port pb and the third port pc communicate with each other via the valve element 31, and the first port pa and the fourth port pd Direct communication. Similarly, since the fourth port pd is blocked by the plug body 30, only communication between the second port pb and the third port pc remains.

As the pressure switching valve 27, a four-way switching valve, which is a standard product used in a refrigeration cycle constituting an ordinary heat pump type air conditioner, is used, but a combination of a plurality of on-off valves may be used instead of the four-way switching valve. Similar effects can be obtained.
Thus, the blade back pressure control mechanism K includes the pressure switching valve 27, the pressure control pipe 16 connected to the pressure switching valve 27, the first branch pipe 28, and the second branch pipe 29. Composed. As described later, the back pressure can be applied to the second blade 12b by switching the high pressure and the low pressure to the second blade back chamber 11b via the closing member 15.

  In the above-described multi-cylinder rotary compressor C and the refrigeration cycle apparatus R that includes the multi-cylinder rotary compressor C and constitutes a refrigeration cycle, a half-capacity operation (cylinder operation) and a full-capacity operation (normal operation) ) Can be selected.

  When the half-capacity operation is selected, the valve body 31 of the pressure switching valve 27 constituting the blade back pressure control mechanism K is switched as shown by a one-dot chain line in FIG. 1, and the second port pb and the third port pc are switched. Communicate. Therefore, the evaporator 22 communicates with the pressure control pipe 16 and the second blade back chamber 11b through the second branch pipe 29 and the pressure switching valve 27.

  At the same time, an operation signal is sent to the motor unit 4 and the rotary shaft 5 is rotationally driven, so that the first and second rollers 9a and 9b rotate eccentrically in the cylinder chambers Sa and Sb. In the first cylinder 6A, the blade 12a is pressed and urged against the spring member 13, and the tip portion slidably contacts the peripheral wall of the roller 9a to bisect the inside of the first cylinder chamber Sa.

The low-pressure refrigerant gas is guided from the accumulator 23 to the suction pipe Pa, and is sucked into the first cylinder chamber Sa and the second cylinder chamber Sb through the suction guide path 25 and the two branch guide paths.
Further, a part of the low-pressure refrigerant gas led out from the evaporator 22 by the blade back pressure control mechanism K is supplied to the second branch pipe 29, the pressure switching valve 27, the pressure control pipe 16, and the guide passage 17 of the closing member 15. Is led to the second blade back chamber 11b, and a low pressure back pressure is applied to the second blade 12b.

The tip of the second blade 12b facing the second cylinder chamber Sb is in a low pressure atmosphere, and the rear end of the second blade 12b facing the second blade back chamber 11b is also in a low pressure atmosphere. No differential pressure is generated between the front end and the rear end of the blade 12b.
When the second roller 9b moves eccentrically with the rotation of the rotating shaft 5, the second blade 12b is kicked by the second roller 9b. The rear end portion of the second blade 12b abuts on the peripheral wall of the second blade back chamber 11b, and the tip portion does not protrude into the cylinder chamber Sb and maintains its position. Accordingly, no compression action is performed in the second cylinder chamber Sb.

  In order to securely fix the rear end portion of the second blade 12b to the peripheral wall of the second blade back chamber 11b, a permanent magnet may be attached to the peripheral wall of the blade back chamber 11b. The second blade 12b is made of a magnetic material, and the above state is obtained by the magnetic adsorption of the permanent magnet. If a high back pressure is applied to the second blade 12b, the blade 12b is easily separated from the permanent magnet.

  On the other hand, in the first cylinder chamber Sa, the first blade 12a receives the elastic force of the spring member 13 and the tip part comes into contact with the peripheral wall of the first roller 9a, so that the first cylinder chamber Sa is used as a compression chamber. Divide into suction chambers. As the roller 9a moves eccentrically, the volume of the compression chamber 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 discharged into the discharge mufflers 8a and 8b, and then the sealed case 1 is filled. The high-pressure gas is led from the sealed case 1 to the condenser 20 through the discharge pipe P, and is condensed and liquefied to be changed into liquid refrigerant. The liquid refrigerant is adiabatically expanded by the expansion device 21, is evaporated by the evaporator 22, and takes the latent heat of evaporation from the air flowing therethrough to perform a freezing action.

The gas refrigerant evaporated and reduced in pressure in the evaporator 22 is led to the accumulator 23 through the suction pipe Pa and separated into gas and liquid, and the separated gas refrigerant is passed from the accumulator 23 to the first cylinder chamber Sa and the second cylinder chamber. The refrigeration cycle as described above is configured by being guided to Sb.
The compression operation is not performed in the second cylinder chamber Sb (cylinder operation), and the compression operation is performed only in the first cylinder chamber Sa, so that the operation is reduced by half.

  When the full capacity operation is selected, the valve element 31 of the pressure switching valve 27 is switched to the position shown by the solid line in FIG. 1, and the first port pa and the second port pb communicate with each other. Accordingly, the discharge pipe P and the first branch pipe 28 are communicated with the pressure control pipe 16 via the pressure switching valve 27, and further communicated from the closing member 15 to the second blade back chamber 11b.

  At the same time, an operation signal is sent to the motor unit 4 and the rotary shaft 5 is rotationally driven, so that the first and second rollers 9a and 9b rotate eccentrically in the cylinder chambers Sa and Sb. In the first cylinder 6A, the blade 12a is pressed and urged against the spring member 13, and the leading edge thereof slidably contacts the peripheral wall of the roller 9a to bisect the inside of the first cylinder chamber Sa.

  The low-pressure refrigerant gas is guided from the accumulator 23 to the suction pipe Pa, and is sucked into the first cylinder chamber Sa and the second cylinder chamber Sb through the suction guide path 25 and the branch guide path. In the first cylinder chamber Sa, the compression action is performed as described above, and the high-pressure gas fills the sealed case 1.

  The high-pressure refrigerant gas filling the sealed case 1 is discharged to the discharge pipe P and circulates in the above-described refrigeration cycle, while a part of the high-pressure gas is discharged from the first branch pipe 28 to the pressure switching valve 27, the pressure The control pipe 16 and the guide passage 17 of the closing member 15 are led to the second blade back chamber 11b to be filled, and a high back pressure is applied to the second blade 12b.

  The tip of the second blade 12b is in a low pressure atmosphere facing the second cylinder chamber Sb, but the rear end is in a high pressure atmosphere facing the second blade back chamber 11b. A differential pressure is generated at the rear end. The second blade 12b receives a high back pressure and is urged toward the tip.

When the second roller 9b moves eccentrically as the rotary shaft 5 rotates, the blade groove 10b reciprocates while the tip of the second blade 12b is in contact with the peripheral surface of the second roller 9b. . The second blade 12b bisects the second cylinder chamber Sb into a compression chamber and a suction chamber, and a compression action is performed.
Accordingly, the first cylinder chamber Sa and the second cylinder chamber Sb are simultaneously compressed and the full capacity operation is performed.

In this way, the second blade back chamber 11b communicating with the second cylinder chamber Sb on the side of the cylinder resting operation via the blade groove 10b is closed by the closing member 15 attached to the lower end surface of the sub bearing 7B. .
The sub-bearing 7B does not need to project a semicircular flange portion for closing the second blade back chamber 11b, and may be a circular body portion. Therefore, when machining the inner diameter hole that pivotally supports the rotary shaft 5 in the auxiliary bearing 7B, the chuck can be easily fixed and high centering accuracy can be obtained. The finish accuracy of the inner diameter hole is increased, and the outer shape has no protrusions, so the size is reduced.

In addition, by connecting the pressure control pipe 16 to the closing member 15, the pressure control pipe 16 can be connected to the intermediate partition plate 2, the cylinders 6A and 6B or the bearings 7A and 7B. The degree of freedom in diameter and connection position is improved.
As a result, the distance between the pressure control pipe 16 and the suction pipe Pa can be increased, the welding and fixing work for the respective sealed cases 1 is facilitated, and the multi-cylinder rotary compressor C with high manufacturability and reliability can be obtained. Can be provided.

Since the insertion positions of the suction pipe Pa and the pressure control pipe 16 with respect to the sealed case 1 are aligned at the same position in the radial direction of the sealed case 1, the suction pipe Pa and the pressure control pipe 16 are the same with respect to the sealed case 1. It can be mounted from the direction, improving assembly.
And since the said suction pipe Pa and the pressure control piping 16 are in the same phase in the radial direction of the airtight case 1, automation of welding fixation becomes easy and improvement of productivity can be obtained.

  Since the pressure control pipe 16 is attached and fixed to the accumulator 23 via the mounting bracket 26, the pressure control pipe 16 and the suction pipe Pa extending from the accumulator 23 can be attached and fixed to the sealed case 1 at the same time. improves. Further, deformation and vibration of the pressure control pipe 16 after installation can be prevented, and a high-quality multi-cylinder rotary compressor C is obtained.

The pressure control pipe 16 is not only attached and fixed to the accumulator 23 but may also be described below.
FIG. 5 is a side view of the sealed case 1 and the accumulator 23 according to the second embodiment.

  As shown in FIG. 5, the mounting bracket 26A made of a metal piece having a certain degree of flexibility is wound around the pressure control pipe 16 and the suction pipe Pa, and then fixed by means such as brazing as appropriate. The Therefore, the pressure control pipe 16 is attached and fixed to the suction pipe Pa with the rigidity of the mounting bracket 26A.

Also in this case, the insertion positions of the suction pipe Pa and the pressure control pipe 16 with respect to the sealed case 1 are the same in the radial direction of the sealed case 1, and the suction pipe Pa and the pressure control pipe are connected to the sealed case 1. 16 can be attached from the same direction, and assemblability is improved.
Then, the pressure control pipe 16 and the suction pipe Pa extending from the accumulator 23 can be attached and fixed to the sealed case 1 at the same time, and the productivity is improved. Deformation and vibration of the pressure control pipe 16 after installation can be prevented, and a high-quality multi-cylinder rotary compressor C can be obtained.

  Since the closing member 15 is formed of cast iron, SMF3 type, or SMF4 type, the guide passage 17 that connects the second blade back chamber 11b and the pressure control pipe 16 can be manufactured by molding.

  That is, by selecting the material of the closing member 15, even if the shape of the guide passage 17 provided in the closing member 15 is complicated, it can be formed at low cost, and the connection position of the pressure control pipe 16 in the closing member 15 can be freely designed. . In addition, the sliding property of the second blade 12b with respect to the closing member 15 can be kept good, and wear and seizure can be prevented to improve reliability.

  In the above-described multi-cylinder rotary compressor C, the blade back pressure control mechanism K guides a low pressure to the second blade back chamber 11b, and no differential pressure is generated between the front end portion and the rear end portion of the second blade 12b. In this way, the following phenomenon occurs during the cylinder resting operation in which the compression action in the second cylinder chamber Sb is stopped.

  That is, the inside of the sealed case 1 is at least filled with the high-pressure gas discharged from the first cylinder chamber Sa and is in a high-pressure atmosphere. The lubricating oil collected in the oil reservoir 14 is also affected and becomes high pressure, and a part of the lubricating oil guided from the lubricating oil supply path provided in the rotating shaft 5 to each sliding portion of the compression mechanism unit 3 has a clearance. Through the second blade back chamber 11b in a low pressure atmosphere.

  Then, the lubricating oil fills the second blade back chamber 11 b, fills the guide passage 17 provided in the closing member 15, and rises in the pressure control pipe 16. Of course, the oil level of the lubricating oil collected in the oil sump 14 is lowered accordingly, and the oil level that should be along the flange portion of the main bearing 7A is the upper end surface of the first cylinder 6A. Go down below.

Furthermore, as the lubricating oil leaking into the pressure control pipe 16 increases and the oil level rises inside, the oil level at the oil reservoir 14 decreases. Finally, there is a possibility that the first cylinder 6A is completely exposed and the second cylinder 6B is exposed from the intermediate partition plate 2. Therefore, the sealing performance and lubricity at each sliding portion are lowered, and the compression performance is adversely affected.
In order to prevent such a phenomenon, it is conceivable to add a large amount of lubricating oil in advance so that the oil level is approximately the same as the upper surface of the double discharge muffler 8a.

  However, the pressure control pipe 16 is filled with the high-pressure gas during full capacity operation in which the compression action is performed in the second cylinder chamber Sb as well as the first cylinder chamber Sa. The lubricating oil that has entered the pressure control pipe 16 until then exits the pressure control pipe 16 and is guided to the guide passage 17 and the second blade back chamber 11b, and further from this clearance, the oil reservoir 14 Return to.

  The oil level of the oil reservoir 14 rises and exceeds the upper surface of the discharge muffler 8a, and finally enters the discharge hole d to fill the discharge valve mechanism with lubricating oil. The gas discharge resistance of the discharge valve mechanism increases, resulting in a decrease in compression performance and an increase in oil discharge, resulting in an increase in lubricant cost. If the oil level further rises, the lubricating oil immerses the lower part of the motor unit 4 and becomes rotational resistance of the rotor, affecting the rotational efficiency.

Therefore, a countermeasure as shown in FIG. 6 is taken.
FIG. 6 is a diagram illustrating the amount of lubricating oil stored in the multi-cylinder rotary compressor C according to the third embodiment. In addition, the same number is attached | subjected to the same component as the above, and new description is abbreviate | omitted. (Hereinafter the same)
That is, from the second blade back chamber 11 b closed by the closing member 15, the pressure switching valve 27 is connected through the guide passage 17 provided in the closing member 15 and the pressure control pipe 16 connected to the closing member 15. The internal volume of the lubricating oil up to the port Pb connection position 2 is V1.

  In contrast, the lubricating oil from the position of the upper end surface of the first cylinder (upper cylinder) 6A to the position of the upper end surface where the upper discharge hole d is provided by the double discharge muffler 8a attached to the main bearing 7A. Let the volume be V2. The internal volume V1 is set smaller than the lubricating oil volume V2 (V1 <V2).

  With such a setting, during the non-cylinder operation (at the time of full capacity operation) in the second cylinder chamber Sb, the lubricating oil that has filled the pressure control pipe 16, the blocking member 15, and the second blade back chamber 11b is filled. Even if all (V1) return to the oil reservoir 14, the oil level of the lubricating oil in the oil reservoir 14 rises only to a position below the upper end surface (V2) of the double muffler 8a.

Therefore, the lubricating oil does not enter the inside from the discharge hole d of the discharge muffler 8a, and the discharge valve mechanism operates normally. And the rotor which comprises an electric motor part does not need to be immersed in lubricating oil, but this rotation efficiency is hold | maintained favorably.
During cylinder resting operation in which the compression action in the second cylinder chamber Sb is stopped, the inside of the sealed case 1 is affected by high pressure, and the lubricating oil in the oil reservoir 14 passes through the clearance of the second blade back chamber 11b. It enters the pressure control pipe 16.

  Even if the oil level of the lubricating oil rises to the position where the four-way switching valve 27 of the pressure control pipe 16 is connected to the second port pb, the oil level in the oil reservoir 14 is the upper end surface of the first cylinder 6A which is the upper cylinder. Hold a position higher than the position. Therefore, the sliding portions between the blade 11a and the blade groove 10a in the first cylinder 6A are all in the lubricating oil and ensure lubricity.

FIG. 7 is a diagram illustrating the amount of lubricating oil stored in the multi-cylinder rotary compressor C according to the fourth embodiment.
Here, a closing plate 35 made of a thin plate is attached to the lower end surface of the second cylinder 6B to close the lower surface opening of the second blade back chamber 11b. The intermediate partition plate 2 is attached to the upper end surface of the second cylinder 6B, covers the second cylinder chamber Sb, and closes the upper surface opening of the second blade back chamber 11b.

  A pressure control pipe 16A is connected to the intermediate partition plate 2, and a guide passage 17A that connects the pressure control pipe 16A and the second blade back chamber 11b is provided. An upper end portion of the pressure control pipe 16A is connected to a communication pipe 37 of a pressure switching means 38 including two on-off valves 36A and 36B and a communication pipe 37 that communicates the on-off valves 36A and 36B.

  In the figure, the left on-off valve 36A is called a first on-off valve, and the right on-off valve 36B is called a second on-off valve. The first on-off valve 36A communicates with the discharge pipe P through a first branch pipe (high pressure pipe) 28a, and the second on-off valve 36B has a suction pipe Pa through a second branch pipe (low pressure pipe) 29a. Communicate with.

  The blade back pressure is generated by the pressure switching means 38 including the pressure control pipe 16A, the first and second on-off valves 36A and 36B, and the communication pipe 37, and the first branch pipe 28a and the second branch pipe 28b. A control mechanism Ka is configured.

When the first on-off valve 36A is closed and the second on-off valve 36B is opened, a low pressure is introduced from the pressure control pipe 16A to the second blade back chamber 11b, and a low pressure back is supplied to the second blade 12b. Since the pressure is applied, the cylinder is rested.
When the first on-off valve 36A is opened and the second on-off valve 36B is closed, a high pressure is introduced from the pressure control pipe 16A to the second blade back chamber 11b, and the high pressure back to the second blade 12b. Since the pressure is applied, the compression operation is performed.

From the second blade back chamber 11b, the guide passage 17A provided in the intermediate partition plate 2 and the pressure control pipe 16 connected to the guide passage 17A are connected to each other between the first and second on-off valves 36A and 36B. The internal volume of the lubricating oil up to the position where it is connected to the communication pipe 37 is V3.
When the lubricating oil volume from the upper end surface position of the first cylinder 6A to the upper discharge hole d position of the double discharge muffler 8a is V2, the internal volume V3 is smaller than the lubricating oil volume V2 (V3 < V2) is set.

  During non-cylinder operation (full capacity operation) in the second cylinder chamber Sb, the maximum amount of lubricating oil is supplied from the pressure control pipe 16A to the oil reservoir 14 through the guide passage 17A and the second blade back chamber 11b. Even when returning, the oil level of the lubricating oil rises only to a position below the position of the upper end surface of the double discharge muffler 8a. Therefore, the above-described effects can be obtained.

  During cylinder resting operation in the second cylinder chamber Sb, the lubricating oil in the oil reservoir 14 enters the pressure control pipe 16 via the second blade back chamber 11b, and the first and second on-off valves 36A, Even if it rises to the position of the communication pipe 37 that communicates 36B, the oil level at the oil reservoir 14 is higher than the position of the upper end surface of the first cylinder 6A. Therefore, the above-described effects can be obtained.

  It should be noted that the blade back chamber control mechanisms K and Ka guide high-pressure gas to the second blade back chamber 11b during full capacity operation in which the compression action is performed in the second cylinder chamber Sb. Moreover, since the second blade back chamber 11b is closed by the closing member 15 (blocking plate 35) and the intermediate partition plate 2, the lubricating oil is introduced from the oil reservoir 14 into the second blade back chamber 11b through the clearance. It is hard to be done.

After all, there is almost no supply of lubricating oil to the sliding portion between the second blade 12b and the blade groove 10b. If the full capacity operation is continued for a long time, the lubricity at the sliding portion is impaired, and the sealing performance and the sliding performance are deteriorated. Therefore, the following measures will be taken.
FIGS. 8A and 8B are views for explaining an oil supply structure to different second blade back chambers 11b according to the fifth embodiment.

First, referring to FIG. 8A, the oil separation device 40 </ b> A is attached to a connection site between the discharge pipe P connected to the upper end portion of the sealed case 1 and the first branch pipe 28. The high-pressure gas that fills the sealed case 1 and is discharged to the discharge pipe P is guided to the oil separator 40A, and the oil component of the lubricating oil contained in the high-pressure gas is separated from the high-pressure gas by the oil separator 40A.
The high-pressure gas, which is only a pure gas component, circulates from the oil separation device 40A including a condenser (not shown) to the refrigeration cycle constituent equipment and performs the above-described action. Since no oil is contained, the efficiency of the refrigeration cycle can be improved.

  On the other hand, the oil content of the lubricating oil separated by the oil separation device 40A is guided to the pressure switching means 27 (38). When full capacity operation is selected, the lubricating oil is guided from the pressure switching means 27 to the second blade back chamber 11b through the pressure control pipe 16, and as a result, the second blade 12b and the blade groove 10b are in contact with each other. Oil is supplied to the sliding part.

  If the full capacity operation is continued for a long time, a sufficient amount of lubricating oil is supplied to the sliding portion between the second blade 12b and the blade groove 10b, thereby ensuring lubricity. There is no occurrence of defects such as seizure, the sealing performance and the slidability around the second blade 12b are ensured, and the compression performance and reliability can be improved.

Next, FIG. 8B will be described. The oil separation device 40B used here is composed of a pipe body having a three-pronged structure formed in a substantially Y shape. Discharge pipes P are connected to the left and right ends of the oil separator 40B. The left end in the figure communicates with the sealed case 1 through the discharge pipe P, and the right end communicates with the condenser.
The first branch pipe 28 is connected to the lower side end of the oil separator 40B, and the configuration ahead of the first branch pipe 28 is as described above.

The high-pressure gas that fills the sealed case 1 and is discharged to the discharge pipe P is guided to the oil separation device 40B, and is guided so as to drop and then rise. The oil content of the lubricating oil contained in the high-pressure gas is separated by the influence of gravity when the high-pressure gas is guided so as to drop downward, and is guided to the first branch pipe 28.
The high-pressure gas from which the oil component of the lubricating oil has been separated is guided upward by the oil separation device 40B and guided to the discharge pipe P beyond this. Therefore, the same effects as those described above can be obtained.

FIG. 9 is an enlarged longitudinal sectional view of a main part of the multi-cylinder rotary compressor C according to the sixth embodiment.
The same components as those shown in FIG. 1 are denoted by the same reference numerals and a new description is omitted. Moreover, although the refrigerating cycle structure of the refrigerating cycle apparatus R is abbreviate | omitted, of course, it has the same structure as what was previously demonstrated in FIG.

Here, the portion of the rotating shaft 5 that is pivotally supported by the main bearing 7A is referred to as “main shaft portion 5a”, and the portion that is pivotally supported by the auxiliary bearing 7B is referred to as “subshaft portion 5b”. Then, the shaft diameter of the main shaft portion 5a is defined as “φDa”, and the shaft diameter of the sub shaft portion 5b is defined as “φDb”.
Further, an axial distance from the axial center position of the first cylinder 6A to the axial load position of the rotary shaft main shaft portion 5a is defined as “L1”. The shaft load position refers to a distance “Da / 2” that is half the shaft diameter φDa of the main shaft portion 5a from the end of the main shaft portion 5a on the first cylinder chamber Sa side.

Further, the axial distance from the axial center position of the first cylinder 6A to the axial center position of the second cylinder 6B is set to “L2”, and the rotational axis auxiliary position is determined from the axial center position of the second cylinder 6B. The axial distance to the axial load position of the shaft portion 5b is “L3”. The axial load position refers to a distance “Db / 2” that is a half of the shaft diameter φDb of the auxiliary shaft portion 5b from the end of the auxiliary shaft portion 5b on the second cylinder chamber Sb side.
Under such conditions, the following equation (1) is set.

  As described above, in the multi-cylinder rotary compressor C that enables switching between the compression operation and the non-compression operation in the second cylinder chamber Sb, which is the cylinder chamber on the side of the auxiliary bearing 7B, the shaft is supported by the main bearing 7A. The relationship between the main shaft portion 5a shaft diameter φDa of the rotary shaft 5 and the sub shaft portion 5b shaft diameter φDb of the rotary shaft 5 supported by the sub bearing 7B is determined.

This is because the first roller 9a is incorporated into the first eccentric portion a formed on the rotating shaft 5 from the side of the sub shaft portion 5b and the influence of the swing of the motor rotor is taken into consideration. The diameter φDa must be set to a large diameter that is at least equal to or larger than the shaft diameter φDb of the auxiliary shaft portion 5b. (ΦDa ≧ φDb)
On the other hand, as the shaft diameter φDb of the auxiliary shaft portion 5b is reduced, the surface pressure against the shaft surface increases. In particular, in the low rotation range (low performance range) of the rotary shaft 5, it is difficult to form a lubricating oil film on the peripheral surface of the countershaft portion 5b, and it is inevitable that the reliability deteriorates.

In the above-described two-cylinder rotary compressor C, when the gas load applied to the main shaft portion 5a is Ga and the gas load applied to the sub shaft portion 5b is Gb, the second load on the side of the sub shaft portion 5b in the low capacity region is set. In order to rest the cylinder chamber Sb, the ratio between the gas load Ga applied to the main shaft portion 5a and the gas load Gb applied to the auxiliary shaft portion 5b is expressed by the following equation (2).
Ga: Gb = (L2 + L3): 1 (2)
Further, the ratio between the surface pressure Fa with respect to the main shaft portion 5a and the surface pressure Fb with respect to the sub shaft portion 5b is expressed by the following equation (3) when the sliding length ratio under load is equal to the shaft diameter ratio. .
Fa: Fb = (L2 + L3) / φDa ² : L1 / φDb ² (3)
Here, in order to ensure a surface pressure equal to or greater than that of the main shaft portion 5a in the sub shaft portion 5b of the rotating shaft 5, the condition (φDa ≧ φDb) described above is added and the equation (1) is derived. .

By satisfying the above expression (1), the maximum theoretical volume flow rate of the working fluid (refrigerant) flowing into the compression mechanism unit 3 within a unit time can be changed to 30 times or more the minimum theoretical volume flow rate.
For example, when this compressor C is used for an air conditioner for home use, continuous operation in which the minimum capacity of the compressor C is made smaller in a minute air-conditioning region in the vicinity of a set temperature where the generation time is extremely long. It becomes possible. There is no intermittent operation as in the prior art, and both energy saving and comfort can be achieved.

At the same time, the maximum capacity of the compressor C can be increased. In particular, even when a large capacity is required such as a heating operation when the outside air is at a low temperature, it is possible to provide an air conditioner that can satisfy the sensible comfort and is energy-saving and highly comfortable.
Eventually, satisfying the expression (1) can sufficiently improve the efficiency by the idle cylinder operation while ensuring the reliability. And the refrigerating cycle apparatus which comprises such a multi-cylinder rotary compressor C and comprises a refrigerating cycle can obtain the improvement of refrigerating efficiency further.

Table 1 is a design example that specifically expresses the above-described expression (1).

  In the above design example, the maximum theoretical volume flow rate of the working fluid (refrigerant) flowing into the compression mechanism unit 3 within a unit time is 40 times the minimum theoretical volume flow rate, and the width of the minimum capacity and maximum capacity of the compressor C is increased. It can be further expanded, and further improvement in compression performance can be obtained.

In this multi-cylinder rotary compressor C, the minimum rotation speed of the rotary shaft 5 for one second is preferably set to 5 rps or more. As a result, a rotational inertia force against torque fluctuation can be secured, and a stable rotation with a small rotational vibration amplitude can be obtained. And the rapid fall of the motor efficiency in a low rotation area can be prevented, and the highly efficient compressor C can be obtained.
Further, in the multi-cylinder rotary compressor C, the maximum number of rotations per second of the rotating shaft 5 is preferably set to 180 rps or less. As a result, an increase in operating noise in the compressor C can be suppressed, and an increase in the amount of lubricating oil discharged from the compressor C to the refrigeration cycle circuit can be suppressed.

FIG. 10 shows the difference between the operating pressure on the horizontal axis and the difference between the suction pressure and the discharge pressure during operation in the two-cylinder rotary compressor C applied to a home air conditioner using R410A as a refrigerant. The result of having examined the crack of the discharge valve with which pressure is taken and provided in the compression mechanism part 3 is shown.
As can be seen from the drawing, in the practical range, at 180 rps or less, the discharge valve constituting the discharge valve mechanism provided in the main bearing 7A and the sub-bearing 7B is not cracked at all, and the highly reliable compressor C can be obtained. Can be provided.

Further, although the multi-cylinder rotary compressor C is capable of idling operation, the suction pipe Pa that communicates the accumulator 23 and the first and second cylinder chambers Sa and Sb has a blade back pressure control mechanism K. Is not provided with the pressure switching means (pressure switching valve) 27.
As a result, the suction resistance does not increase even under operating conditions in which the refrigerant suction flow rate into the cylinder chambers Sa and Sb is large. This is advantageous because the variable operating range can be expanded to a higher flow rate without lowering the compression efficiency.

  Further, in the above-described multi-cylinder rotary compressor C, the efficiency of the motor that is the motor unit 4 is reduced when the rotational speed of the rotary shaft 5 is reduced. Therefore, in the low capacity range, the cylinder resting operation, which is the non-compression operation state, is performed in the second cylinder chamber Sb, and the motor efficiency is controlled to be increased by increasing the number of rotations of the rotating shaft 5 by a factor of two.

  However, in this case, the shaft sliding loss is increased by increasing the rotation speed, and in the design specification having a large shaft sliding loss ratio, the motor efficiency cannot be improved by the cylinder resting operation. In particular, in the multi-cylinder rotary compressor R, the portions with the largest shaft sliding loss are the first eccentric portion a and the second eccentric portion b formed on the rotary shaft 5, and the eccentric portions a and b It is necessary to reduce sliding loss.

  Since the auxiliary shaft portion 5b shaft diameter φDb of the rotating shaft 5 is set smaller than the main shaft portion 5a shaft diameter φDa, the diameters of the first and second eccentric portions a, b can be reduced accordingly. That is, in the compressor C, it is possible to obtain a reduction in the sliding loss of the first and second eccentric parts a and b, which is the place where the shaft sliding loss is the largest, and the operation variable width can be increased on the higher flow rate side without lowering the efficiency. Can be expanded.

As shown in FIG. 9 again, the sliding length of the first eccentric portion a and the second eccentric portion b formed on the rotating shaft 5 with respect to the first roller 9a and the second roller 9b is “L4”. And the shaft diameters of the first eccentric part a and the second eccentric part b are “φDcr”.
In FIG. 11, when the horizontal axis is (L4 / φDcr) and the vertical axis is the sliding loss [W] at each eccentric part a, b, the sliding at L4 / φDcr and each eccentric part a, b. FIG. 6 is a characteristic diagram of loss, and shows comparisons under the same capacity for two-cylinder operation and non-cylinder operation.

The eccentric portion sliding loss [W] is set such that the sliding length L4 of the first and second eccentric portions a and b with respect to the first and second rollers 9a and 9b is constant, and the first and second eccentric portions a and b are constant. The eccentric part shaft diameter φDcr of 2 is changed and led. The number of revolutions during idle cylinder operation is twice that during 2-cylinder operation.
The change during two-cylinder operation is indicated by a broken line, and the change during idle cylinder operation is indicated by a solid line. From FIG. 11, it can be seen that the loss difference of the eccentric portion sliding loss [W] gradually increases as the L4 / φDcr value decreases.

  FIG. 12 is a characteristic diagram of L4 / φDcr and total efficiency at the same capacity when the refrigeration cycle apparatus in the embodiment of the present invention is applied as an air conditioner. Also here, L4 / φDcr is taken on the horizontal axis, the sliding length L4 with respect to the first and second rollers 9a, 9b in the first and second eccentric portions a, b is constant, and the eccentric portion shaft diameter φDcr is set to be constant. Guided by changing. The vertical axis is the overall efficiency.

From FIG. 12, in order to obtain the efficiency improvement by the idle cylinder operation,
L4 / φDcr ≧ 0.43 (4)
The conclusion that the expression (4) needs to be satisfied is obtained.

In the refrigeration cycle apparatus R, for example, when the refrigeration cycle operation is performed while the set temperature is lowered in an environment where the outside air temperature is low, the refrigerant that should evaporate in the evaporator 22 cannot be completely evaporated. When the refrigeration cycle operation is terminated as it is, the liquid refrigerant remains in the evaporator 22 and is in a so-called sleep state.
An accumulator 23 is interposed between the evaporator 22 and the compressor C. However, when a large amount of liquid refrigerant is instantaneously introduced from the evaporator 22, complete gas-liquid separation cannot be performed in the accumulator 23.

Therefore, at the time of starting the next refrigeration cycle operation, a part of the liquid refrigerant that has fallen into the evaporator 22 is sucked into the compressor C as it is. A so-called liquid back phenomenon occurs, leading to damage to the discharge valve mechanism in the compression mechanism section 3.
As will be described later, the multi-cylinder rotary compressor C has a countermeasure when a liquid back phenomenon occurs.

FIG. 13 is a longitudinal cross-sectional view in which a part of the multi-cylinder rotary compressor C according to the seventh embodiment is omitted and the main part is enlarged.
The same components as those shown in FIG. 1 are denoted by the same reference numerals and a new description is omitted. Although the refrigeration cycle configuration of the refrigeration cycle apparatus R is also omitted, it is needless to say that the same configuration as that described above with reference to FIG. 1 is provided.

  As the pressure switching valve (pressure switching means) 27 constituting the blade back pressure control mechanism K, the same one as described above is used. Therefore, a first branch pipe (high-pressure pipe) 28 branched from the discharge pipe P that communicates the sealed case 1 and the condenser 20 is connected to the first port pa of the pressure switching valve 27.

  A pressure control pipe 16 that communicates with the guide passage 17 of the closing member 15 is connected to the second port pb of the pressure switching valve 27. The third port pc is connected to a second branch pipe (low pressure pipe) 29a, which will be described later, branched from a suction pipe Pa that communicates the evaporator 22 and the accumulator 23.

  The fourth port pd of the pressure switching valve 27 is closed with the plug 30. The valve body 31 accommodated therein is electromagnetically switched between a position where the third port pc and the fourth port pd are communicated and a position where the second port pb and the third port pc are communicated. Is done. The first port pa is always open, and the fourth port pd is always closed.

The second branch pipe 29a is branched from the upstream portion of the accumulator 23 of the suction pipe Pa. The branch position of the branch pipe 29a from the suction pipe Pa is located below the pressure switching valve 27.
The second branch pipe 29 a extends obliquely upward from the suction pipe Pa and has an end connected to the third port pc of the pressure switching valve 27. Since the pipe diameter of the second branch pipe 29a is selected to be narrower than the suction pipe Pa, it is as if the suction pipe Pa is a trunk, and the second branch pipe 29a is branched from the trunk (suction pipe Pa). It becomes the composition which becomes.

  In such a piping configuration around the pressure switching valve 27, the operation of the pressure switching valve 27 itself is basically the same as that shown in FIG. That is, when the half-capacity operation is selected, the valve body 31 in the pressure switching valve 27 moves and the second port Pb and the third port Pc communicate with each other, and the low-pressure refrigerant is introduced from the evaporator 22 to the pressure switching valve 27. It is burned.

  Then, the pressure control pipe 16 guides the second blade back chamber 11b to apply a low pressure to the second blade 12b. Since the second cylinder chamber Sb is in a low pressure atmosphere, no differential pressure is generated between the front end portion and the rear end portion of the blade 12b. In the cylinder chamber Sb, a compression operation is not performed and a cylinder resting operation is performed.

  When full capacity operation is selected, the first port Pa and the second port Pb communicate with each other, and the high-pressure gas is guided to the pressure control pipe 16 via the first branch pipe 28 and the pressure switching valve 27. A high back pressure is applied to the second blade 12b in the second blade back chamber 11b, a differential pressure is generated at the front and rear ends of the blade 12b, and the compression operation is also performed in the second cylinder chamber Sb.

  The problem is that when the half-capacity operation is selected, the pressure switching valve 27 and the suction pipe Pa communicate with each other via the second branch pipe 29a. In other words, as described above, when the liquid refrigerant is stagnant in the evaporator 22, a part of the liquid refrigerant led out from the evaporator 22 is led to the second branch pipe 29 a before being led to the accumulator 23. End up.

  Originally, the liquid refrigerant is guided from the second branch pipe 29a to the pressure switching valve 27 and further accumulated in the second blade back chamber 11b via the pressure control pipe 16. Since the liquid refrigerant has no lubricity, the pressure switching valve 27 inhibits the smooth movement switching operation of the valve element 31, and the second blade back chamber 11b inhibits the smooth reciprocating motion of the second blade 12b. Resulting in.

  However, here, a part of the sleeping liquid refrigerant that has exited the evaporator 22 and led to the suction pipe Pa is diverted to the second branch pipe 29 a at the upstream portion of the accumulator 23. As described above, the second branch pipe 29a is connected to the suction pipe Pa in an obliquely upward direction so as to be connected in a so-called branch shape.

  The specific gravity of the refrigerated liquid refrigerant is heavy compared to the specific gravity of the refrigerant completely evaporated by the evaporator 22. For this reason, even if a part of the liquid refrigerant enters the second branch pipe 29a from the suction pipe Pa, only the evaporative refrigerant having a low specific gravity rises in the second branch pipe 29a. The evaporative refrigerant is guided to the pressure switching valve 27, but most of the liquid refrigerant having a high specific gravity remains in the branch pipe 29a.

  The liquid refrigerant remaining in the second branch pipe 29a eventually returns along the inclination of the branch pipe 29a and reaches the suction pipe Pa. Then, it naturally flows down through the suction pipe Pa and is led to the accumulator 23 where it is gas-liquid separated.

Eventually, even if a part of the liquid refrigerant stagnated in the evaporator 22 enters the second branch pipe 29a, a substantial gas-liquid separation action is performed in the branch pipe 29a. That is, the second branch pipe 29a, which is a low-pressure pipe, functions as a gas-liquid separation section that separates the liquid refrigerant that has entered from the suction pipe Pa into a gas-liquid separation.
Smooth reciprocation of the valve body 31 of the pressure switching valve 27 and the second blade 12b without affecting the cost, with a simple configuration in which the second branch pipe 29a is simply connected in a branched manner from the suction pipe Pa. Dynamic operation is ensured, deterioration of lubricity can be avoided, and high reliability can be obtained.

Furthermore, in order to ensure smooth reciprocating motion of the second blade 12b to avoid deterioration of lubricity and to obtain higher reliability, the multi-cylinder rotary compressor C is controlled as described later. It will be certain.
14 (A) and 14 (B) are schematic refrigeration cycle configuration diagrams of a refrigeration cycle apparatus R including a multi-cylinder rotary compressor C in the embodiment of the present invention, and FIG. 14 (A) shows full capacity operation. The refrigeration cycle when selected is shown, and FIG. 14B shows the refrigeration cycle when the half-capacity operation is selected.

The same components as those of the refrigeration cycle apparatus R shown in FIG. In the figure, reference numeral 40 denotes a control unit that controls the multi-cylinder rotary compressor C and other refrigeration cycle components and controls the pressure switching valve 27.
When the refrigeration cycle operation is started, the control unit 40 selects the pressure switching valve 27 so that the full capacity operation shown in FIG. If this state is continued to some extent, the refrigeration load decreases, so this time, the pressure switching valve 27 is switched to the half capacity operation state shown in FIG.

The refrigeration cycle operation may be terminated as it is, or the full capacity operation and the half capacity operation may be repeated several times to reach the end. Preferably, the control unit 40 may perform control to switch to the half-capacity operation state at the end of the refrigeration cycle operation.
Further, at the time of starting the refrigeration cycle operation, the control unit 40 is temporarily in a half-capacity operation state, and the second blade back chamber 11b and the second branch pipe 29 on the low pressure side through the pressure control pipe 16. Control to communicate with each other. And when predetermined time passes, control which switches to a full capacity driving state is made.

For example, when the outside air falls at night, there is a possibility that refrigerant condensed and liquefied in the pressure control pipe 16 may be stored. In such a state, the next refrigeration cycle operation may be started.
When the full capacity operation state is established from the start of operation as usual, the high-pressure refrigerant gas is guided to the pressure control pipe 16 via the pressure switching valve 27 and at the same time, the liquid refrigerant staying in the pressure control pipe 16 is retained. It will be guide | induced to the 2nd braid | blade back chamber 11b. The liquid refrigerant lowers the viscosity of the lubricating oil in the second blade back chamber 11b and obstructs the smooth reciprocating motion of the second blade 12b.

  As described above, if the pressure switching valve 27 is switched to the half-capacity operation state at the end of the refrigeration cycle operation, the operation is started in the half-capacity operation state when the next refrigeration cycle is started. The compression operation is performed at Sa, and the second roller 9b rotates idly in the second cylinder chamber Sb.

  Alternatively, the control unit 40 once controls the pressure switching valve 27 so as to communicate with the second blade back chamber 11b and the second branch pipe 29 on the low pressure side via the pressure control pipe 16 when the refrigeration cycle is started. To do. Since the capacity is reduced by half, the compression operation is performed in the first cylinder chamber Sa, and the second roller 9b rotates idly in the second cylinder chamber Sb.

  On the other hand, the evaporative refrigerant is sucked into the first cylinder chamber Sa from the evaporator 22 via the suction pipe Pa, and the suction pipe Pa is under a negative pressure. When the pressure of the second blade back chamber 11b on one end side of the pressure control pipe 16 is compared with the pressure of the suction pipe Pa through the pressure switching valve 27 on the other end side, the second blade back chamber 11b is compared. The side is higher than the suction pipe Pa side.

  Therefore, the liquid refrigerant staying in the pressure control pipe 16 is guided from the pressure switching valve 27 to the suction pipe Pa and further separated into gas and liquid by the accumulator 23. After the liquid refrigerant in the pressure control pipe 16 is thus prevented from being guided to the second blade back chamber 11b, the control unit 40 enters the full capacity operation state shown in FIG. Is switched and controlled.

  If the half-capacity operation state is set at the end of the refrigeration cycle operation, there is no need to switch back to the half-capacity operation state at the start of the refrigeration cycle operation, and the control flow is simplified. In any case, by controlling the multi-cylinder rotary compressor C as described above, smooth lubricity of the second blade 12b is ensured and high reliability is obtained.

  In the above embodiment, the closing member 15 is attached to the second cylinder 6B and the second blade back chamber 11b is closed. However, the present invention is not limited to this, and the first cylinder on the upper side is not limited thereto. The closing member 15 may be attached to 6A, the first blade back chamber 11a may be configured as a closing structure, and the first cylinder chamber Sa side may be switched between the compression operation and the non-compression operation.

In the above embodiment, the low pressure gas is guided from the suction pipe Pa to the first cylinder chamber Sa and the second cylinder chamber Sb through the suction guide path 25 and the branch guide path of the intermediate partition plate 2. It is not limited to.
That is, the compressor is of a type in which two suction pipes are extended from the accumulator 23, one suction pipe communicates with the first cylinder chamber Sa, and the other suction pipe communicates with the second cylinder chamber Sb. May be.

Specifically, the multi-cylinder rotary compressor C shown in FIG. 15 according to the eighth embodiment or the multi-cylinder rotary compressor C shown in FIG. 16 according to a modification of the eighth embodiment will be described. it can.
First, referring to FIG. 15, the components of the refrigeration cycle apparatus R other than the multi-cylinder rotary compressor C are omitted here. The electric motor unit 4 constituting the multi-cylinder rotary compressor C is the same as that described above, and the compression mechanism unit 3 is basically the same as that described above.

  The difference in the compression mechanism section 3 is that the intermediate partition plate 2A interposed between the first cylinder 6A and the second cylinder 6B is thinner than the intermediate partition plate 2 described above. It is used. The intermediate partition plate 2A is not connected to a suction pipe as shown in FIG. 1 and others.

The intermediate partition plate 2A simply covers the inner diameter portion of the first cylinder 6A together with the main bearing 7A to form the first cylinder chamber Sa. Further, the second cylinder chamber Sb is only formed by covering the inner diameter portion of the second cylinder 6B together with the auxiliary bearing 7B.
Instead, two suction pipes Pa1 and Pa2 extend from the accumulator 23, and are connected to the first cylinder 6A and the second cylinder 6B, respectively. The first cylinder 6A and the second cylinder 6B are provided with guide passages that connect the suction pipes Pa1 and Pa2 to the cylinder chambers Sa and Sb.

  The rollers 9a and 9b accommodated in the cylinder chambers Sa and Sb move eccentrically, and the blades 12a and 12b reciprocate following the eccentric movement. As a result, the low-pressure evaporated refrigerant passes through the suction pipes Pa1 and Pa2 from the accumulator 23. The basic action of being sucked into the first cylinder chamber Sa and the second cylinder chamber Sb is not changed.

  Further, the upper surface opening of the second blade back chamber 11b is covered by the intermediate partition plate 2A, and the lower surface opening is covered by the closing member 15 attached to the lower surface of the second cylinder 6B, thereby providing a sealed structure. There is no change. There is no change in the configuration and piping connection of the pressure control piping 16 and the pressure switching valve 27 constituting the blade back pressure control mechanism K.

  In the multi-cylinder rotary compressor C, the full capacity operation in which the first cylinder chamber Sa and the second cylinder chamber Sb perform the compression action by the switching control with respect to the pressure switching valve 27, and the second cylinder chamber Sb. The compression operation is stopped (cylinder operation), and it is possible to switch to the half-capacity operation in which the compression action is performed only in the first cylinder chamber Sa.

  On the other hand, in the multi-cylinder rotary compressor C shown in FIG. 16, the two suction pipes Pa1 and Pa2 are extended from the accumulator 23 and connected to the first cylinder 6A and the second cylinder 6B. There is no change. The intermediate partition plate 2A interposed between the first and second cylinders 6A and 6B is a thin plate as in FIG.

  As a difference from FIG. 15, the closing member 15 is attached to the upper surface of the first cylinder 6A, and the upper surface opening of the first blade back chamber 11a is covered. The lower surface opening of the second blade back chamber 11a is covered with the intermediate partition plate 2A, thereby forming a sealed structure. The pressure switching valve 27 constituting the blade back pressure control mechanism K, the pressure control piping 16 and other piping configurations are unchanged.

  Therefore, in the multi-cylinder rotary compressor C, the full capacity operation in which the first cylinder chamber Sa and the second cylinder chamber Sb perform the compression action by the switching control with respect to the pressure switching valve 27, and the first cylinder chamber. The compression operation in Sa is stopped (cylinder operation), and it is possible to switch to the half-capacity operation that performs the compression action only in the second cylinder chamber Sb.

In FIG. 4, the positions where the pressure control pipe 16 and the suction pipe Pa penetrate the sealing case 1 are shown.
Here, the two suction pipes Pa1 and Pa2 are extended from the accumulator 23 and communicated with the first cylinder chamber Sa and the second cylinder chamber Sb as described in FIGS. 15 and 16. The connection structure of the pressure control pipe 16 and the two suction pipes Pa1 and Pa2 to the sealed case 1 will be described.

FIG. 17A shows a pressure control pipe 16 for the sealed case 1 when the closing member 15 is attached to the second cylinder 6B described in FIG. 15 to close the second blade back chamber 11b, FIG. 5 is a schematic view showing a through position of second suction pipes Pa1 and Pa2.
That is, since the first suction pipe Pa1 is at the top and the second suction pipe Pa2 is at the bottom, the insertion portions ha and hb with respect to the sealed case 1 are arranged vertically. Since the pressure control pipe 16 is connected to the closing member 15 attached to the lower surface portion of the second cylinder 6B, the insertion portion g is positioned below the second suction pipe insertion portion hb.

The insertion portion ha of the first suction pipe Pa1, the insertion portion hb of the second suction pipe Pa2, and the insertion portion b of the pressure control pipe 16 with respect to the sealed case 1 are all provided on the same axis L. However, the present invention is not limited to this.
FIG. 17B is a schematic diagram showing the pressure control piping 16 and the first and second suction pipes Pa1 and Pa2 penetrating positions with respect to the sealed case 1 in a modified example of the configuration of FIG.

That is, the insertion part ha of the first suction pipe Pa1 and the insertion part hb of the second suction pipe Pa2 with respect to the sealed case 1 are aligned on the same axis L, but the insertion part g of the pressure control pipe 16 is the axis L. It is provided at a position deviated from.
FIG. 18A shows a pressure control pipe 16 for the hermetic case 1 when the closing member 15 is attached to the first cylinder 6a described in FIG. 16 to close the first blade back chamber 11a. FIG. 5 is a schematic view showing a through position of second suction pipes Pa1 and Pa2.

  Since the first suction pipe Pa1 is in the upper part and the second suction pipe Pa2 is in the lower part, the insertion parts ha and hb with respect to the sealed case 1 are arranged vertically. Since the pressure control pipe 16 is connected to the closing member 15 attached to the upper surface of the first cylinder 6a, the insertion part g is positioned above the first suction pipe insertion part ha.

  The insertion portion ha of the first suction pipe Pa1 with respect to the sealed case 1, the insertion portion hb of the second suction pipe Pa2, and the insertion portion b of the pressure control pipe 16 are all provided on the same axis L. As schematically shown in FIG. 18B, the insertion portion g of the pressure control pipe 16 may be provided at a position off the axis L.

  In the multi-cylinder rotary compressor C described above, the motor unit 4 uses a brushless DC synchronous motor or an AC motor. For the oil reservoir 14 formed at the inner bottom of the sealed case 1, polyol ester oil or ether oil (mineral oil, alkylbenzene, PAG, or fluorine oil may be used depending on the refrigerant) is used as the lubricating oil.

In connecting the suction pipe Pa and the pressure control pipe 16 to the sealed case 1, a connection hole is provided in the sealed case 1 in advance, and a guide pipe is connected thereto. Further, a tapered pipe is connected to the tips of the suction pipe Pa and the pressure control pipe 16 and inserted into the guide pipe.
In the first embodiment, the tapered pipe is sealed and joined to the intermediate partition plate 2 and the second blade back chamber 11b by press-fitting.

As described above with reference to FIG. 4, the pressure control pipe 16 is supported and fixed at a substantially intermediate portion in the vertical direction by the mounting bracket 26 provided on the side wall surface of the accumulator 23.
Actually, the pressure control piping 16 on the upper side extending from the second port pb of the pressure switching valve 27 and the lower side extending from the second blade back chamber 11b through the sealing case 1 are actually used. A pressure control pipe 16 is connected.

The connection positions of the pressure control pipes 16 at the upper and lower parts are set at a position above the liquid level of the oil reservoir 14 formed at the inner bottom of the sealed case 1. In particular, the end portion of the lower pressure control pipe 16 may be expanded so that a pressure sealing capella for performing an airtight test with the compressor C alone can be attached.
In any case, the mounting property of the pipe to the sealed case 1 is improved, and the brazing material such as brazing does not wrap around the brazing material, and automatic brazing with a fixed burner can be easily performed.

Further, if the taper pipe for connecting the pressure control pipe 16 is attached to an adapter that is not directly connected to the second blade back chamber 11b, the deformation of the blade groove 10b due to the pipe press-fit can be reliably prevented.
The pressure control pipe 16 only applies a back pressure to the second blade 12b and does not require a gas flow rate. Therefore, a pipe with a thin pipe diameter can be used, which is advantageous from the viewpoint of securing the pressure resistance strength in the sealed case 1.

The above-described multi-cylinder rotary compressor C has been described as a two-cylinder type as a two-cylinder rotary compressor, but it can be applied to a compressor of three or more cylinders. The present invention can be applied to a compressor of a type having a different excluded volume.
The present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the components without departing from the scope of the invention in the implementation stage. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above-described embodiments.

  DESCRIPTION OF SYMBOLS 1 ... Sealing case, 5 ... Rotating shaft, 4 ... Electric motor part, 3 ... Compression mechanism part, C ... Multi-cylinder rotary compressor, 2 ... Intermediate partition plate, Sa ... 1st cylinder chamber, Sb ... 2nd cylinder Chamber, 10a, 10b ... blade groove, 11a ... first blade back chamber, 11b ... second blade back chamber, 6A ... first cylinder, 6B ... second cylinder, 7A ... main bearing, 7B ... auxiliary bearing A ... first eccentric portion, b ... second eccentric portion, 9a ... first roller, 9b ... second roller, 12a ... first blade, 12b ... second blade, 13 ... spring member ( (Elastic body), 15 ... blocking member, 16 ... pressure control pipe, 17 ... guide passage, Pa ... suction pipe, 26 ... mounting bracket, 23 ... accumulator, 26a ... mounting bracket, d ... discharge hole, 8a ... discharge muffler, 28 ... 1st branch pipe (high pressure pipe), 29 ... 2nd branch (Low pressure pipe), 27 ... pressure switching valve (pressure switching means), P ... discharge pipe, 40A, 40B ... oil separator, 5a ... main shaft part, 5b ... subshaft part, 28 ... high pressure pipe (first branch pipe) ), 29, 29a ... low pressure pipe (second branch pipe), 20 ... condenser, 21 ... expansion device, 22 ... evaporator.

Claims (9)

In a multi-cylinder rotary compressor that houses an electric motor unit and a compression mechanism unit connected via a rotating shaft in a sealed case,
The compression mechanism is
A first cylinder which is provided with an intermediate partition plate and in which a cylinder chamber into which low-pressure gas is introduced is formed in each inner diameter portion, and a blade back chamber which is communicated with these cylinder chambers via a blade groove And a second cylinder;
A bearing provided on end faces of the first cylinder and the second cylinder and covering the cylinder chamber together with the intermediate partition plate;
The rotating shaft having an eccentric portion accommodated in each cylinder chamber of the first cylinder and the second cylinder;
Rollers that are fitted to the eccentric portion of the rotating shaft and rotate eccentrically in the cylinder chamber as the rotating shaft rotates,
A blade that is movably accommodated in the blade groove, and that divides the cylinder chamber into two chambers in a state in which a tip is in contact with the roller peripheral wall;
Either one of the blade back chambers provided in the first cylinder and the second cylinder includes an elastic body that applies an elastic force to the rear end portion of the blade so that the blade front end portion contacts the roller peripheral wall,
Either one of the blade back chambers is attached to the bearing-side end surface of the cylinder, and is closed by a closing member that is a separate part from the bearing, and an intermediate partition plate,
A pressure control pipe for switching between a high pressure and a low pressure is connected to the closing member, and a guide passage is provided for communicating the pressure control pipe with the other blade back chamber. Cylinder rotary compressor. The suction pipe for introducing the low-pressure gas into the cylinder chambers of the first cylinder and the second cylinder and the pressure control pipe connected to the closing member are inserted into the sealing case in the circumferential direction of the sealing case. The multi-cylinder rotary compressor according to claim 1, wherein the multi-cylinder rotary compressor is aligned at the same position. The pressure control pipe connected to the closing member is fixed to the suction pipe for introducing the low-pressure gas into the cylinder chambers of the first cylinder and the second cylinder via an attachment fitting, or to the suction pipe. The multi-cylinder rotary compressor according to any one of claims 1 and 2, wherein the multi-cylinder rotary compressor is fixed to a communicating accumulator via a mounting bracket. The first cylinder and the second cylinder are arranged vertically, and a discharge muffler having a discharge hole is attached to a bearing that covers the upper cylinder,
The pressure control pipe is connected to a pressure switching means communicating with a high-pressure pipe for guiding high pressure and a low-pressure pipe for guiding low pressure,
The internal volume from the blade back chamber closed by the closing member to the pressure switching means via the guide passage and pressure control piping provided in the closing member is from the upper end surface position of the upper cylinder to the discharge hole of the discharge muffler. 2. The multi-cylinder rotary compressor according to claim 1, wherein the multi-cylinder rotary compressor is set smaller than a lubricating oil volume up to a position. A discharge pipe for discharging and guiding the high-pressure gas compressed by the compression mechanism is connected to the sealed case,
A high pressure pipe branched from the discharge pipe and communicating with the pressure control pipe is provided,
A separation device for separating the lubricating oil contained in the high-pressure gas discharged from the sealed case to the discharge pipe is provided at a branch portion between the discharge pipe and the high-pressure pipe,
The high-pressure gas separated by this separation device is guided to the discharge pipe ahead of the separation device, and the lubricating oil separated by the separation device is guided to the blade back chamber via the high-pressure tube and the pressure control piping. The multi-cylinder rotary compressor according to claim 1. The bearing in the compression mechanism section is
A main bearing attached to the motor part side of the first cylinder and covering the inner diameter part of the first cylinder together with the intermediate partition plate to form a first cylinder chamber, and a counter-motor part of the second cylinder A secondary bearing mounted on the side and covering the inner diameter part of the second cylinder together with the intermediate partition plate to form a second cylinder chamber;
The rotation axis is
A main shaft portion pivotally supported by the main bearing, and a subshaft portion pivotally supported by the sub bearing;
The following formula (1) is satisfied, where φDa is a shaft diameter of the main shaft portion of the rotating shaft and φDb is a shaft diameter of the sub shaft portion of the rotating shaft. Item 4. The multi-cylinder rotary compressor according to Item 1.

However,
L1: Axial distance from the axial center position of the first cylinder to the axial load position of the rotary shaft main shaft portion (distance of half of the main shaft portion shaft diameter from the first cylinder chamber side end portion in the main shaft portion).
L2: An axial distance from the axial center position of the first cylinder to the axial center position of the second cylinder.
L3: Axial direction from the axial center position of the second cylinder to the axial load position of the rotary shaft auxiliary shaft portion (distance half the diameter of the auxiliary shaft portion from the second cylinder chamber side end in the auxiliary shaft portion) distance. The pressure control pipe is connected to a pressure switching means communicating with a high-pressure pipe for guiding high pressure and a low-pressure pipe for guiding low pressure,
The pressure switching means has a port to which the high pressure pipe is connected, a port to which the low pressure pipe is connected, and a port to which the pressure control pipe is connected, and is connected to the pressure control pipe connection port inside. A pressure switching valve containing a valve body that moves so as to selectively communicate the high-pressure pipe connection port and the low-pressure pipe connection port,
The low-pressure pipe is branched from a suction pipe for introducing low-pressure gas into the cylinder chambers of the first cylinder and the second cylinder, and a gas-liquid separation unit that separates liquid refrigerant that has entered from the suction pipe into a gas-liquid separator The multi-cylinder rotary compressor according to claim 4, wherein A refrigeration cycle apparatus comprising the multi-cylinder rotary compressor according to any one of claims 1 to 7, a condenser, an expansion device, and an evaporator to constitute a refrigeration cycle. The multi-cylinder rotary compressor constituting the refrigeration cycle is
During the refrigeration cycle operation, the blade back chamber communicates with the high-pressure pipe branched from the pipe between the multi-cylinder rotary compressor on the high-pressure side and the condenser via the pressure control pipe, or Regardless of which one communicates with the low pressure pipe branched from the pipe between the evaporator on the low pressure side and the multi-cylinder rotary compressor,
9. The refrigeration cycle apparatus according to claim 8, wherein the refrigeration cycle apparatus is controlled to communicate with the blade back chamber and the low pressure pipe on the low pressure side through the pressure control pipe when the refrigeration cycle operation is started.

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