JP2010163927A - Multicylinder rotary compressor and refrigerating cycle apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a small multicylinder rotary compressor of high performance, capable of switching normal operation and cylinder cut-off operation and securing rigidity even in the case of thinning the wall thickness of a cylinder constituting a compression mechanism particularly on the side of cylinder cut-off operation, and to provide a refrigerating cycle apparatus including the multicylinder rotary compressor to improve refrigerating cycle efficiency. <P>SOLUTION: A second compression mechanism 2B in the multicylinder rotary compressor A includes a cylinder cut-off mechanism K for separating the tip edge of a second blade 15b from the peripheral surface of a roller 13b to attain the suspension of compression operation in a second cylinder chamber 14b. The cylinder cut-off mechanism includes a blade back chamber 16b holding the rear end of the blade and forming a closed space, and a pressure lead-in passage 20 for leading pressure into the blade back chamber 16b from the end face of a cylinder 8B. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention accommodates an electric motor unit and a plurality of compression mechanism units that are connected to each other through a rotating shaft in a sealed case, and at least one compression mechanism unit is capable of stopping a compression operation depending on conditions. The present invention relates to a multi-cylinder rotary compressor provided with a cylinder mechanism and a refrigeration cycle apparatus that constitutes a refrigeration cycle using the multi-cylinder rotary compressor.

  In recent years, a two-cylinder type multi-cylinder rotary compressor having two sets of upper and lower cylinders is being standardized. In such a multi-cylinder rotary compressor, if a cylinder that always performs a compression action and a cylinder that can be switched between a compression operation and a compression stop operation according to conditions can be provided, the operation according to the load can be performed. This is advantageous because the specifications are expanded.

  [Patent Document 1] discloses the above-described multi-cylinder rotary compressor. In this technique, a first cylinder in which a first cylinder chamber is formed is provided with a blade that receives a back pressure of a compression spring, and a peripheral surface of a roller in which a tip end edge of the blade is fitted in a rotating shaft eccentric portion And always elastically contact.

  In the first cylinder chamber, the gas is always compressed and discharged as long as the rotating shaft is driven to rotate and the roller rotates eccentrically. Further, the blade provided in the second cylinder has its rear end portion reciprocally accommodated in the blade back chamber, and means for switching and guiding the low pressure gas and the high pressure gas to the blade back chamber according to conditions. Connected.

  When the low pressure gas evaporated by the evaporator is guided to the second cylinder chamber, the high pressure gas is guided to the blade back chamber and a high pressure back pressure is applied to the blade, the blade tip becomes low pressure and the rear end becomes high pressure. A differential pressure is generated at the front and rear ends.

  Accordingly, the blade tip end edge is pressed and urged so as to be in sliding contact with the circumferential surface of the roller, and a compression action is performed in the second cylinder chamber. In both cylinder chambers, normal operation (full capacity operation) is performed, which simultaneously performs compression.

  Depending on the conditions, the low pressure gas is switched to the blade back chamber on the second cylinder side, and a low pressure back pressure is applied to the blade. The front and rear ends of the blade have the same low-pressure atmosphere and no differential pressure is generated. The blade is pushed away by the roller, and the roller rotates idly and no compression action is performed. A cylinder resting operation (half-capacity operation) in which the compression action is performed only in the first cylinder chamber.

JP 2006-300048 A

  By adopting a configuration capable of switching between normal operation and non-cylinder operation as in [Patent Document 1], it is possible to obtain a multi-cylinder rotary compressor with extremely high efficiency and a large capacity variable range. Become.

  However, as a specific pressure switching means, pressure is introduced into the blade back chamber from the outer peripheral surface of the cylinder. In other words, the end of the pressure introduction pipe for introducing high pressure or low pressure is passed through the peripheral wall of the sealed case constituting the compressor and connected to the hole provided through the outer peripheral surface of the cylinder and the blade back chamber. Yes.

  In the cylinder, it is necessary to provide a hole for connecting the pressure introducing pipe to a place where the distance between the outer peripheral surface and the blade back chamber peripheral surface is very small and only a thin wall remains. is there. For this reason, the thick portion around the pressure introduction pipe connecting portion of the cylinder is further cut.

  There is a risk that the rigidity of the cylinder will be significantly reduced, the accuracy will be deteriorated when parts are processed, or there will be problems such as deformation during assembly, leading to performance degradation and reliability degradation. If the design for ensuring the seal length is ensured by sufficiently increasing the hole insertion and connection length of the pressure introducing pipe, the outer diameter of the cylinder must be increased, leading to an increase in size of the compressor.

  The present invention has been made on the basis of the above circumstances, and the object of the present invention is to enable switching between normal operation and idle cylinder operation, and in particular, the wall thickness of the cylinder constituting the compression mechanism portion on the side of idle cylinder operation. A multi-cylinder rotary compressor that can ensure rigidity even when the thickness is reduced, and that is small and has high performance, and a refrigeration cycle apparatus that includes this multi-cylinder rotary compressor and that improves the refrigeration cycle efficiency. It is.

In order to satisfy the above-described object, the present invention provides a multi-cylinder rotary compressor in which an electric motor unit coupled via a rotary shaft and a plurality of compression mechanism units are housed in a sealed case, and at least one compression mechanism unit. Includes a cylinder having a cylinder chamber in which the roller is rotatably accommodated eccentrically, a blade provided in the cylinder and having a tip end edge abutting against the circumferential surface of the roller and dividing the cylinder chamber into two along the rotation direction of the roller; A discharge valve mechanism that guides gas compressed in the cylinder chamber into the sealed case, and a cylinder resting mechanism that enables the compression operation in the cylinder chamber to be stopped by separating the end edge of the blade from the roller peripheral surface. The cylinder resting mechanism includes a blade back chamber that is provided in the cylinder to form a closed space and accommodates the rear end portion of the blade in a reciprocating manner, and the blade back chamber from the end surface of the cylinder. And a pressure introduction passage for introducing a force.
In order to satisfy the above object, the refrigeration cycle apparatus of the present invention forms a refrigeration cycle with the above-described multi-cylinder rotary compressor, a condenser, an expansion mechanism, and an evaporator.

  According to the present invention, it is possible to secure rigidity even when the thickness of the cylinder constituting the compression mechanism portion on the side of the cylinder resting operation is made thin, and it is possible to secure a small size and high performance multi-cylinder rotary compressor, and It is possible to provide a refrigeration cycle apparatus that is provided with a cylinder rotary compressor and can improve the refrigeration cycle efficiency.

It is the longitudinal cross-sectional view and refrigeration cycle block diagram of the multicylinder rotary compressor which concern on one embodiment in this invention, Comprising: The state at the time of normal operation is shown especially. It is the longitudinal cross-sectional view and refrigeration cycle block diagram of a multicylinder rotary compressor based on the embodiment, Comprising: The state at the time of a cylinder resting operation is shown especially. It is a longitudinal cross-sectional view of the multi-cylinder rotary compressor which abbreviate | omitted the refrigerating cycle structure based on other embodiment in this invention, Comprising: The state at the time of normal operation and the state at the time of a cylinder rest operation are shown.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional structure of a multi-cylinder rotary compressor A and a schematic configuration diagram of a refrigeration cycle apparatus R including the multi-cylinder rotary compressor A. (Note that, in order to avoid complications in the drawings, components that are not denoted by reference numerals are not illustrated even if they are described. Alternatively, components that are illustrated are not denoted by reference numerals in the drawings. ,the same)
First, the configuration of the refrigeration cycle apparatus R will be described. A two-cylinder rotary compressor A, a condenser B, an expansion mechanism C, an evaporator D, and an accumulator E are provided. Communicate through P.

  As will be described later, the refrigerant gas compressed by the multi-cylinder rotary compressor A is discharged to the refrigerant pipe P, and circulates in the order of the condenser B, the expansion valve C, the evaporator D and the accumulator E which are the above components. And the refrigeration cycle works. The refrigerant is sucked into the multi-cylinder rotary compressor A from the accumulator E through the suction refrigerant pipe Pa.

Next, the multi-cylinder rotary compressor A will be described in detail.
In the figure, reference numeral 1 denotes a sealed case, and a lower portion in the sealed case 1 is provided in a state where a plurality of compression mechanism portions, ie, a first compression mechanism portion 2A and a second compression mechanism portion 2B are vertically stacked. The motor part 3 is provided in the upper part. The first and second compression mechanism portions 2A and 2B and the electric motor portion 3 are connected via a rotating shaft 4.

  For example, a brushless DC synchronous motor (which may be an AC motor or a commercial motor) is used for the electric motor unit 3, and a stator 5 that is press-fitted and fixed to the inner surface of the sealed case 1 and a predetermined gap inside the stator 5 exist. And a rotor 6 fitted to the rotating shaft 4.

  The first compression mechanism portion 2A and the second compression mechanism portion 2B have an intermediate partition plate 7 interposed therebetween. The first compression mechanism portion 2A is formed on the upper surface side of the thick intermediate partition plate 7 and includes a first cylinder 8A. The second compression mechanism portion 2B is formed on the lower surface side of the intermediate partition plate 7 and includes a second cylinder 8B.

  In the first cylinder 8A, a part of the outer peripheral surface is in close contact with the inner peripheral surface of the sealed case 1, and the remaining part has a gap. The main bearing 11 is superposed on the upper surface portion, and a mounting bolt is inserted and fixed to the intermediate partition plate 7 through the main bearing 11 and the second cylinder 8B.

  The outer surface of the second cylinder 8B is press-fitted into the inner peripheral surface of the sealed case 1 over the entire circumference, and is attached and fixed via a fixture or the like. Further, the auxiliary bearing 12 and the valve cover are superimposed on the lower surface portion of the second cylinder 8B, and are fixedly attached to the intermediate partition plate 7 via mounting bolts.

  Eccentric shaft portions c and d are integrally provided at positions passing through the insides of the first cylinder 8A and the second cylinder 8B of the rotating shaft 4, respectively. The connecting portion between the eccentric shaft portions c and d faces the intermediate partition plate 7.

  The eccentric shaft portions c and d are formed with the same amount of eccentricity from the central axis of the main shaft portion and the sub shaft portion of the rotating shaft 4 with a phase difference of about 180 °, and have the same diameter. A first roller 13a is fitted to the eccentric shaft portion c, and a second roller 13b is fitted to the eccentric shaft portion d. The first and second rollers 13a and 13b are formed to have the same outer diameter.

  Upper and lower surfaces of the inner diameter portions of the first cylinder 8A and the second cylinder 8B are partitioned by the main bearing 11 and the intermediate partition plate 7, and the intermediate partition plate 7 and the auxiliary bearing 12, respectively. A first cylinder chamber 14a is formed in the inner diameter portion of the first cylinder 8A, and a second cylinder chamber 14b is formed in the inner diameter portion of the second cylinder 8B.

  The first roller 13a is accommodated in the first cylinder chamber 14a so as to be eccentrically rotatable, and the second roller 13b is accommodated in the second cylinder chamber 14b so as to be eccentrically rotatable. The first and second rollers 13a and 13b have a phase difference of 180 ° from each other, and part of the circumferential surfaces along the respective axial directions can rotate eccentrically while making line contact with the circumferential walls of the cylinder chambers 14a and 14b.

  The intermediate partition plate 7 is provided with a suction conduction path S that extends from the accumulator E and is connected to an end of a suction refrigerant pipe Pa that penetrates the sealed case 1. The suction conduction path S is provided in the central axis direction from a part of the outer peripheral surface of the intermediate partition plate 7 as shown by a one-dot chain line in the figure, and is branched into an upper oblique direction and a lower oblique direction at a predetermined portion.

  The upper oblique branch path of the suction conduction path S communicates with the suction portion of the first cylinder chamber 14a. The lower oblique branch path of the suction conduction path S communicates with the suction portion of the second cylinder chamber 14b.

  That is, the intermediate partition plate 7 is thickened, and the suction conduction path S that communicates the accumulator E with the first cylinder chamber 14a and the second cylinder chamber 14b is provided within the thickness range.

  The first cylinder 8A is provided with a blade housing groove in which the first blade 15a can move while sliding, and the rear end of the first blade 15a reciprocates integrally with the blade housing groove end. A first blade back chamber 16a that is freely accommodated is provided continuously.

  Further, the first cylinder 8A is provided with a lateral hole communicating the outer peripheral surface and the first blade back chamber 16a, and the spring member 17 is accommodated therein. The spring member 17 is interposed between the end surface of the rear end of the first blade 15a and the inner peripheral surface of the sealed case 1, and applies an elastic force (back pressure) to the blade 15a so that the end edge of the front end of the roller 13a surrounds the roller 13a. A compression spring that is brought into contact with the surface.

  On the other hand, the second cylinder 8B is provided with a blade housing groove in which the second blade 15b can move while sliding, and the rear end portion of the second blade 15b is housed in the blade housing groove end. The second blade back chamber 16b is connected continuously.

  The end edges of the blades 15a and 15b are formed in a semicircular shape in plan view. The end edge of the first blade 15a with respect to the first cylinder chamber 14a is always in line contact with the circumferential surface of the cylindrical first roller 13a by the action of the spring member 17 regardless of the rotation angle of the roller. .

  As will be described later, if the condition is satisfied, the end edge of the second blade 15b with respect to the second cylinder chamber 14b can come into line contact with the circumferential surface of the cylindrical roller 13b regardless of the rotation angle of the roller.

  The upper surface of the second blade back chamber 16 b is closed by the intermediate partition plate 7, and the lower surface is closed by the flange portion of the auxiliary bearing 12. As described above, the rear end portion of the second blade 15b is fitted in the second blade back chamber 16b so as to freely reciprocate. The second blade back chamber 16b is a closed space because it is surrounded by the above components.

  In the second blade back chamber 16b, an urging holding body 18 that is one of a permanent magnet, an electromagnet, and an elastic body (such as a tension spring) is provided only at a portion facing the end surface of the rear end portion of the second blade 15b. Is inserted.

  When the biasing holding body 18 is a permanent magnet or an electromagnet, as will be described later, when the second blade 15b approaches the biasing holding body 18 in a state where a high back pressure is not applied to the second blade 15b. The urging holder 18 can magnetically attract the rear end of the blade 15b. At this time, the tip of the second blade 15b is held away from the peripheral surface of the second roller 13b that rotates eccentrically, and the second roller 13b rotates idly.

  The magnetic force of the urging holder 18 is such that the high pressure of the second blade back chamber 16b is high when a high pressure is guided to the second blade back chamber 16b and a high back pressure is applied to the second blade 15b. Due to the pressure difference from the pressure in the second cylinder chamber 14b, the second blade 15b is sufficiently smaller than the force biased toward the second roller 13b.

  When the biasing holding body 18 is an elastic body, for example, a tension spring, one end of the tension spring is fixed to the blade 15b, and the blade 15b is always biased in a direction to separate it from the peripheral surface of the second roller 13b. .

  However, the elastic force is greater than the force by which the second blade 15b is biased toward the second roller 13b due to the pressure difference between the high pressure of the second blade back chamber 16b and the pressure of the second cylinder chamber 14b. Is small enough.

  On the other hand, a guide hole 19 is drilled from a part of the outer peripheral surface toward the central axis in a range where the thickness of the intermediate partition plate 7 does not overlap with the suction conduction path S in the intermediate partition plate 7. The The end of the guide hole 19 opens to the end surface of the cylinder 8B at a portion facing the blade back chamber 16b of the second cylinder 8B, and the guide hole 19 and the blade back chamber 16b communicate with each other.

  Then, from the outside of the sealed case 1, one end of a pressure introducing passage 20 made of a pipe is inserted into the guide hole 19 from the outer peripheral surface of the intermediate partition plate 7 through the sealed case 1. The pressure introducing passage 20 extends to a position in the vicinity of the opening end that opens to the portion of the guide hole 19 facing the blade back chamber 16b.

  The pressure introducing passage 20 rises and bends substantially in an L shape outside the sealed case 1, and the rising end is connected to one port of the three-way valve 21 controlled by the control unit. The other port of the three-way valve 21 is connected to an end portion of the pressure introduction passage 20 that extends horizontally toward the sealing case 1 and penetrates the sealing case 1 so that the opening end faces the inside of the sealing case 1. .

  The pressure introduction passage 20 connected to the remaining port of the three-way valve 21 is branched from a midway portion of the suction refrigerant pipe Pa that communicates the accumulator E and the suction conduction path S of the intermediate partition plate 7.

  Naturally, the sealing case 1 penetrating portion of the pressure introducing passage 20 has a sealing structure, and there is no external leakage of gas or lubricating oil filling the inside of the sealing case 1, and the sealing case 1 external air enters the inside of the sealing case 1. There is no intrusion.

  In this way, the second blade back chamber 16b, the pressure introduction passage 20, the three-way valve 21, and the urging holding body 18 constitute the cylinder resting mechanism K. In the second cylinder chamber 14b, as will be described later. Enables switching between compression action and non-compression action.

  On the other hand, an oil reservoir for collecting lubricating oil is formed at the inner bottom of the sealed case 1. The surface of the lubricating oil in the oil reservoir is located near the flange portion of the main bearing 11 constituting the first compression mechanism 2A. From here, the first compression mechanism 2A, the intermediate partition plate 7 and the second partition plate 7 All of the compression mechanism 2B is immersed in the lubricating oil.

  Discharge valve mechanisms 23a and 23b are provided in the main bearing 11 constituting the first compression mechanism portion 2A and the auxiliary bearing 12 constituting the second compression mechanism portion 2B, and each cylinder chamber 14a is provided. , 14b and covered with a valve cover.

  As will be described later, the discharge valve mechanisms 23a and 23b are opened while the refrigerant gas compressed in the cylinder chambers 14a and 14b has risen to a predetermined pressure. The compressed refrigerant gas is discharged from the discharge valve mechanisms 23 a and 23 b into the valve cover, and further guided into the sealed case 1.

Next, the operation of the multi-cylinder rotary compressor A configured as described above will be described.
The control unit selects normal operation (full capacity operation) at the start of the air conditioning operation or at a high load.
That is, as shown in FIG. 1, the control unit switches and controls the three-way valve 21 that constitutes the cylinder resting mechanism K, and the opening end that faces the pressure introduction passage 20 in the sealed case 1 and the intermediate partition The opening end connected to the guide hole 19 of the plate 7 is communicated.

And an operation signal is sent to the motor part 3 via an inverter. The rotating shaft 4 is driven at a high rotation, and the rollers 13a and 13b rotate eccentrically in the cylinder chambers 14a and 14b.
In the first cylinder 8A, since the first blade 15a is always elastically pressed and biased by the spring member 17, the tip of the blade 15a is in sliding contact with the circumferential surface of the first roller 13a, and One cylinder chamber 14a is divided into a suction chamber and a compression chamber. With the first blade 15a retracted most, the space capacity of the first cylinder chamber 14a is maximized.

  The first cylinder chamber 14a and the second cylinder constituting the two-cylinder rotary compressor A are connected to the low-pressure refrigerant gas from the accumulator 17 through the refrigerant pipe Pa and the suction conduction path S provided in the intermediate partition plate 7. It is sucked into the chamber 14b.

  In the first cylinder chamber 14a, with the eccentric rotation of the first roller 13a, the rolling contact position of the roller 13a with respect to the inner peripheral surface of the first cylinder chamber 14a moves, and the compression chamber partitioned by the cylinder chamber 14a moves. Volume decreases. Therefore, the gas previously introduced into the first cylinder chamber 14a is gradually compressed.

  The rotating shaft 4 is continuously rotated, the capacity of the compression chamber in the first cylinder chamber 14a is further reduced, the gas is compressed, and when the pressure rises to a predetermined pressure, the discharge valve mechanism 23a is opened. The high-pressure refrigerant gas is discharged from the discharge valve mechanism 23a through the valve cover into the sealed case 1 and is filled.

  At least, the inside of the sealed case 1 becomes a high-pressure atmosphere by the compression action in the first cylinder chamber 14a. A part of the high-pressure gas filled in the sealed case 1 enters the inside from the open end of the pressure introducing passage 20 constituting the cylinder resting mechanism K as shown by an arrow in the figure, and the intermediate partition plate via the three-way valve 21 7 is guided to the second blade back chamber 16b from the opening end of the guide hole 19 provided in the guide 7.

  That is, the pressure introduction passage 20 introduces the high-pressure gas from the end surface of the second cylinder 8A into the second blade back chamber 16b. Since the second blade back chamber 16b is formed in a closed space, the pressure is increased by the high-pressure gas that is filled, and a high-pressure back pressure is applied to the rear end portion of the second blade 15b accommodated therein.

  As described above, low-pressure (suction pressure) gas is led from the accumulator E to the second cylinder chamber 14b via the suction refrigerant pipe Pb. The second blade 15b has a rear end portion accommodated in the blade back chamber 16b in a high pressure atmosphere, and a front end portion protruding into the second cylinder chamber 14b has a low pressure atmosphere.

  Accordingly, a differential pressure is generated between the front end portion and the rear end portion of the second blade 15b. The rear end of the second blade 15b is pushed to a high pressure, and the end edge of the second blade 15b comes into contact with the peripheral surface of the second roller 13b. The roller 13b in the second cylinder chamber 14b rotates eccentrically with a phase difference of 180 ° from the eccentric rotation of the first roller 13a in the first cylinder chamber 14a.

The same high compression action as that in which the blade 15a on the first cylinder chamber 14a side is pressed and urged by the spring member 17 to perform the compression action is also carried out in the second cylinder chamber 14b, and the compressed high pressure Gas is discharged into the sealed case 1 via the discharge valve mechanism 23b.
After all, in the two-cylinder rotary compressor A, normal operation is performed in which both cylinder chambers 14a and 14b perform compression.

  The high-pressure refrigerant gas discharged from the sealed case 1 to the refrigerant pipe P condenses and liquefies in the condenser B, adiabatically expands in the expansion mechanism C, and takes the latent heat of evaporation from the heat exchange air in the evaporator D to perform a cooling operation. . Then, the gas and liquid are separated by the accumulator E, and again sucked into the two-cylinder rotary compressor A from the suction refrigerant pipe Pa and compressed, and circulates in the above-described path.

Although the air conditioning load is large at the time of starting, if the air conditioning operation is continued to some extent, the air conditioning load becomes small. At this time, the operation is automatically switched from the normal operation to the non-cylinder operation (operation that halves the compression capacity).
FIG. 2 shows the state of cylinder resting operation. (In FIG. 2, only the main part is given a reference numeral.)
The control unit performs switching control of the three-way valve 21 provided in the pressure introduction passage 20. Therefore, the suction refrigerant pipe Pa connected from the accumulator E to the suction conduction path S and the second blade back chamber 16b provided in the second cylinder 8B are communicated with each other by the pressure introduction passage 20.

And an operation signal is sent to the motor part 3 via an inverter. The rotary shaft 4 is driven at a low rotation, and the rollers 13a and 13b rotate eccentrically in the cylinder chambers 14a and 14b.
In the first cylinder 8A, the first blade 15a is always elastically pressed and biased by the spring member 17. As described above, the refrigerant gas introduced into the first cylinder chamber 14a from the accumulator E through the suction refrigerant pipe Pa is compressed, and the high-pressure gas enters the sealed case 1 through the discharge valve mechanism 23a. Released.

  The sealed case 1 is filled with high-pressure gas, and a part of the high-pressure gas enters the inside from the opening end of the pressure introduction passage 20, but the entry is stopped because the three-way valve 21 provided here is switched.

Low pressure gas is introduced from the accumulator E to the pressure introduction passage 20 through the suction refrigerant pipe Pa. Then, a low pressure gas is introduced into the blade back chamber 16b from the end face of the second cylinder 8B through the guide hole 19, and a low pressure back pressure is applied to the rear end portion of the second blade 15b.

  On the other hand, low-pressure gas is led from the accumulator E through the suction refrigerant pipe Pb to the second cylinder chamber 14b, and the tip of the second blade 15b is in a low-pressure atmosphere. Therefore, the second blade 15b does not generate a differential pressure at the front and rear end portions.

  The second blade 15b does not follow the eccentric rotation of the second roller 13b, is pushed away by the roller 13b, and stops at a position away from the peripheral surface of the roller 13b. In this state, the rear end portion of the second blade 15b is close to the biasing holder 18 and is magnetically attracted. The roller 13b idles and no compression action is performed in the second cylinder chamber 14b.

Eventually, if the three-way valve 21 is controlled to be switched from the state shown in FIG. 1 to FIG. Will be.
In this way, switching between normal operation (full capacity operation) and idle cylinder operation (capacity half operation) is possible with the opening and closing action of the three-way valve 21, simplifying the piping configuration and simplifying the control. In addition, the cost can be greatly reduced by reducing the parts cost.

  In particular, the pressure introduction passage 20 guides high pressure or low pressure directly to the blade back chamber 16b from the end face of the second cylinder 8B, and applies high pressure or low pressure to the rear end portion of the second blade 15b. I did it.

Therefore, it is not necessary to provide a pressure introduction path or a pressure introduction pipe in the outermost peripheral portion of the second cylinder 8B, and the necessary rigidity can be ensured even when the thickness of the second cylinder 8B is reduced in order to improve performance. Thus, a multi-cylinder rotary compressor A having a small size, good performance, and high reliability can be obtained.
Further, the first compression mechanism portion 2A and the second compression mechanism portion 2B are provided on both end faces via the intermediate partition plate 7, and the pressure introducing passage 20 constituting the cylinder resting mechanism K in the intermediate partition plate 7 is provided. Is provided.

  That is, it is necessary to provide cylinder chambers 14a and 14b and blade housing grooves in the first cylinder 8A and the second cylinder 8B, and to provide discharge valve mechanisms 23a and 23b in the main bearing 11 and the sub bearing 12, respectively. It is difficult to ensure rigidity.

  On the other hand, the intermediate partition plate 7 is originally provided only as being interposed between the first compression mechanism portion 2A and the second compression mechanism portion 2B, and has a high degree of design freedom. Therefore, by increasing the thickness of the intermediate partition plate 7, high rigidity can be ensured, and a pressure introduction passage 20 is provided to communicate with the blade back chamber 16b.

Therefore, it is possible to provide the compressor A with high accuracy and small deformation during assembly. The seal length for inserting the pressure introducing passage 20 made of a pipe into the guide hole 19 can be easily secured, and the performance deterioration due to the leak failure can be prevented.
And the improvement of the refrigerating cycle efficiency is obtained by comprising the multi-cylinder rotary compressor A mentioned above and comprising a refrigerating cycle.

In the above-described embodiment, the second cylinder 8B provided with the cylinder resting mechanism K is attached and fixed to the sealed case 1.
On the other hand, the outermost peripheral portion of the first cylinder 8A not provided with the cylinder resting mechanism K accommodates a compression spring 17 that presses the distal end portion of the first blade 15a against the peripheral surface of the first roller 13a. A hole is provided. Accordingly, the strength against deformation of the blade housing groove that slidably accommodates the first blade 15a is lowered.

  If the outer peripheral surface of the first cylinder 8A is attached and fixed to the inner peripheral surface of the sealed case 1 by means such as welding, the blade housing groove may be deformed, and the smooth operation of the first blade 15a is impaired. . Therefore, the first cylinder 8A is fixedly attached to the intermediate partition plate 7 via a mounting bolt.

  On the other hand, in the second cylinder 8B provided with the cylinder resting mechanism K, since the horizontal hole as in the first cylinder 8A is not provided, the rigidity of the outermost peripheral portion is ensured. By attaching and fixing the cylinder 8B to the hermetic case 1, a multi-cylinder rotary compressor A with a small deformation of the blade housing groove can be obtained.

  Further, in the above-described embodiment, the cylinder resting mechanism K includes a blade back chamber 16b, a pressure introduction passage 20 that introduces discharge pressure into the blade back chamber 16b, and a three-way valve 21 that opens and closes communication of the pressure introduction passage 20. However, the present invention is not limited to this, and a cylinder resting mechanism Ka having a structure as shown in FIGS. 3A and 3B may be used.

  The urging holding body 18 is attached, and the rear end portion of the second blade 15b is reciprocably accommodated, and the configuration of the blade back chamber 16b constituting the closed space is not changed. Further, there is no change in the pressure introduction passage 20a as a portion for introducing pressure from the end face of the second cylinder 8B to the blade back chamber 16b through the guide hole 19.

  Here, the pressure introduction passage 20a is bent in a substantially U shape outside the sealed case 1, and one open / close valve 21a controlled by the control unit is provided in the bent portion. The other end of the substantially U-shaped pressure introduction passage 20a is a peripheral wall of the hermetic case 1 and penetrates into a part spaced apart from the bottom part to project into the hermetic case 1 and open.

  Although not particularly illustrated, as described above, most of the first compression mechanism portion 2A, the intermediate partition plate 7 and the second compression mechanism portion 2B are oil sump portions formed on the inner bottom portion of the sealed case 1. Soaked in lubricating oil. Therefore, the protrusion of the pressure introduction passage 20a to the sealed case 1 is immersed in the lubricating oil in the oil reservoir.

  By providing such a cylinder resting mechanism Ka, during the normal operation, as shown in FIG. 3A, the on-off valve 21a of the cylinder resting mechanism Ka is opened so that both end portions of the pressure introducing passage 20a communicate with each other. Control to switch to.

  A normal compression action is performed in the first cylinder chamber 14a, and high-pressure gas discharged from the first cylinder chamber 14a through the discharge valve mechanism 23a is filled in the sealed case 1. The lubricating oil in the oil reservoir also rises in pressure, enters the inside from the lower end opening of the pressure introduction passage 20a as shown by the arrow in the figure, and enters the blade back chamber from the end face of the second cylinder 8B via the on-off valve 21a. 16b.

  The high pressure lubricating oil fills the blade back chamber 16b and applies a high pressure back pressure to the second blade 15b. On the other hand, low-pressure gas is introduced into the second cylinder chamber 14b through the accumulator E and the suction refrigerant pipe Pa, and a differential pressure is generated at the front and rear end of the second blade 15b.

  Therefore, the end edge of the second blade 15b is in contact with the peripheral surface of the second roller 13b, and always bisects the second cylinder chamber 14b with the eccentric rotation of the roller 13b. The compression action is performed in the second cylinder chamber 14b together with the first cylinder chamber 14a, and the normal operation is performed.

  As shown in FIG. 3B, by closing the on-off valve 21a, the lubricating oil whose pressure has risen in the oil reservoir is prevented from flowing and does not fill the blade back chamber 16b. The high-pressure lubricating oil filled in the blade back chamber 16b during normal operation leaks into the second cylinder chamber 14b from the gap between the side surface of the second blade 15b and the blade storage groove of the second cylinder 8B, and the blade back chamber 16b. The pressure in the chamber 16b decreases.

  As a result, the pressure in the blade back chamber 16b and the pressure in the second cylinder chamber 14b become substantially equal, and no differential pressure is generated. When the roller 13b rotates eccentrically, the second blade 15b is pushed away and is magnetically attracted to the biasing holding body 18. The roller 13b rotates idly and there is no compression action in the second cylinder chamber 14b.

Eventually, the cylinder resting operation is performed in which the compression action continues only in the first cylinder chamber 14a.
If such a cylinder resting mechanism Ka is used, the pressure introduction into the blade back chamber 16b is performed from the end face of the second cylinder 8B as compared with the cylinder resting mechanism K described above. Compared to 21a, an inexpensive on-off valve 21a is provided, and the piping structure of the pressure introduction passage 21a is simplified, so that parts costs and assembly man-hours can be reduced.

The guide hole is provided in the intermediate partition plate, and one end of the pressure introducing passage is connected to the guide hole. However, the guide hole may be provided in the main bearing, the auxiliary bearing, or the like.
Further, in any configuration of the multi-cylinder rotary compressor A, the excluded volume in the second compression mechanism section 2B including the cylinder resting mechanisms K and Ka is made different from the excluded volume of the other compression mechanism sections. In addition to the switching between the full capacity operation and the half capacity (half) operation as described above, it is possible to perform the switching operation with an arbitrary capacity.

In any configuration of the multi-cylinder rotary compressor A, the two-cylinder compressor including the first compression mechanism 2A and the second compression mechanism 2B has been described. However, the present invention is not limited to this. The same effect can be obtained even when applied to a compressor having three or more cylinders.
Further, in the (first) compression mechanism portion 2A that does not include the cylinder resting mechanisms K and Ka, the same effect can be obtained even if a so-called swing type unit in which the blade 15a and the roller 13a are integrated is employed. .

  The multi-cylinder rotary compressor A described above and the refrigeration cycle apparatus provided with the compressor A are not limited to the configuration described above, and various modifications can be made without departing from the scope of the present invention. Of course there is.

  DESCRIPTION OF SYMBOLS 1 ... Sealing case, 4 ... Rotating shaft, 3 ... Electric motor part, 2A ... 1st compression mechanism part, 2B ... 2nd compression mechanism part, 13a, 13b ... Roller, 14a ... 1st cylinder chamber, 14b ... 1st 2 cylinder chambers, 8A ... 1st cylinder, 8B ... 2nd cylinder, 15a ... 1st blade, 15b ... 2nd blade, 23a, 23b ... discharge valve mechanism, K ... cylinder resting mechanism, 16b ... blade Back chamber, 20 ... pressure introduction passage, 7 ... intermediate partition plate, A ... multi-cylinder rotary compressor, B ... condenser, C ... expansion mechanism, D ... evaporator.

Claims (3)

In a multi-cylinder rotary compressor that houses an electric motor unit and a plurality of compression mechanism units that are connected via a rotating shaft in a sealed case,
At least one compression mechanism is
A cylinder having a cylinder chamber in which a roller is rotatably accommodated eccentrically;
Provided in this cylinder, the blade whose tip end edge is in contact with the peripheral surface of the roller and bisects the cylinder chamber along the rotation direction of the roller, and the gas compressed in the cylinder chamber is guided into the sealed case A discharge valve mechanism, and a cylinder resting mechanism that enables the compression operation in the cylinder chamber to be stopped by separating the tip end edge of the blade from the roller circumferential surface,
The restless mechanism is
A blade back chamber that is provided in the cylinder, forms a closed space, and reciprocally accommodates a rear end portion of the blade;
A pressure introduction passage for introducing pressure from the end face of the cylinder into the blade back chamber;
A multi-cylinder rotary compressor characterized by comprising: The plurality of compression mechanism portions are provided on both end faces via an intermediate partition plate,
The multi-cylinder rotary compressor according to claim 1, wherein the intermediate partition plate is provided with the pressure introducing passage constituting the cylinder resting mechanism.   A refrigeration cycle apparatus comprising the multi-cylinder rotary compressor according to claim 1 and a condenser, an expansion mechanism, and an evaporator to constitute a refrigeration cycle.

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