WO2006073048A1

WO2006073048A1 - Refrigerating cycle device and rotary hermetic compressor

Info

Publication number: WO2006073048A1
Application number: PCT/JP2005/023031
Authority: WO
Inventors: Shoichiro Kitaichi; Toshimasa Aoki; Takeshi Tominaga; Koji Satodate
Original assignee: Toshiba Carrier Corporation
Priority date: 2005-01-04
Filing date: 2005-12-15
Publication date: 2006-07-13
Also published as: JP4700624B2; CN101094992A; US20080092586A1; KR20070086908A; JPWO2006073048A1

Abstract

A refrigerating cycle device has a pressure switching mechanism (K) for performing, depending on the magnitude of load, switching between a normal compression operation and an operation stop of one compression mechanism section (2) of a rotary hermetic compressor (C). The pressure switching mechanism (K) has a bifurcation tube (30) provided with an on-off valve (31) in its intermediate section and communicating the high pressure side of a refrigerating cycle and a suction tube (16b); an auxiliary suction tube (35) connected within an accumulator (17) to an end section of the suction tube; a check valve (36) installed on either the auxiliary suction tube (35) or the suction tube (16b) and preventing a reverse flow of a refrigerant into the accumulator (17); and a guide pipe (34) for fixing and holding either the suction tube (16b) or the auxiliary suction tube (35) at the accumulator (17).

Description

Specification

Refrigeration cycle apparatus and rotary hermetic compressor

Technical field

[0001] The present invention relates to a refrigeration cycle having a rotary hermetic compressor that can switch one compression mechanism portion of a plurality of sets to be operated or stopped depending on the magnitude of a load. The present invention relates to a kul device and a rotary type hermetic compressor.

Background art

A general rotary hermetic compressor has a configuration in which a motor unit and a rotary compression mechanism connected to the motor unit are accommodated in a hermetic case and compressed by the compression mechanism. It is a high-pressure type in the case that discharges gas into the sealed case.

[0003] In the compression mechanism section, an eccentric roller is accommodated in a cylinder chamber formed in the cylinder, and the tip edge of the vane always elastically contacts the peripheral surface of the eccentric roller. The cylinder chamber is divided into two chambers by vanes, and the suction part is connected to one chamber side, and the discharge part is connected to the other chamber side. A suction pipe is connected to the suction part, and the discharge part is opened in the sealed case.

[0004] In recent years, a two-cylinder type rotary hermetic compressor having two sets of the compression mechanism portions above and below is being standardized. If such a compressor can be equipped with a compression mechanism that always performs compression operation and a compressor mechanism that enables switching between compression operation and operation stop according to the load, the specifications can be expanded. It will be advantageous.

[0005] For example, Japanese Patent Application Laid-Open No. 11-247786 (Patent Document 1) discloses a compressor having two cylinder chambers in which a vane in one of the cylinder chambers is forced from a roller as needed. There is disclosed a technique characterized in that it is provided with a high-pressure introducing means for holding the cylinder chamber apart and increasing the pressure of the cylinder chamber to interrupt the compression action.

[0006] Also, Japanese Patent No. 2803456 (Patent Document 2) discloses a compressor in which a bypass passage as a high-pressure introducing means is provided from the inside of a sealed container to a suction pipe, and one cylinder chamber has a compression action. A technique is disclosed in which the vane is in contact with the roller by the action of an elastic member even during the idle cylinder operation, and the compression chamber is always partitioned by the vane.

Disclosure of the invention [0007] By the way, although the compressor of Patent Document 1 described above is excellent in terms of function, a high-pressure introduction hole that communicates one cylinder chamber and the inside of the sealed case is provided in order to constitute a high-pressure introduction means. The refrigeration cycle is provided with a two-stage throttle mechanism, is branched from an intermediate portion of the throttle mechanism, communicates with one of the vane chambers, and is provided with a bypass refrigerant pipe having an electromagnetic on-off valve in the middle.

[0008] That is, it is necessary to form a hole for providing a high-pressure introduction means for the compressor, and the expansion device on the refrigeration cycle must be a two-stage expansion mechanism. In addition, a bypass refrigerant pipe is connected between the two-stage throttle mechanism and the cylinder chamber, which complicates the configuration and adversely affects costs.

[0009] Further, in the compressor of Patent Document 2, a bypass pipe connecting process for bypassing the discharge side and the suction side is required for the sealed container, which has an adverse effect on the cost and is always constant even during the cylinder-clamping operation. Due to the elastic contact of the roller with the roller, there is a problem that the efficiency decreases due to the presence of some compression work and sliding loss.

[0010] In any technique, when high pressure is introduced into a predetermined compression mechanism by operating high pressure introduction means, the high pressure refrigerant may flow backward from the suction pipe connected to the compressor to the accumulator. However, none of the patent documents describes a specific structure for preventing backflow.

[0011] The present invention has been made based on the above circumstances, and an object of the present invention is to provide a pressure switching means for one of the compression mechanism parts constituting the rotary type hermetic compressor, and to reduce the size of the load. Refrigeration that can be switched between compression operation and operation stop according to the flow rate, prevents reverse flow of refrigerant to the accumulator, and prevents thermal adverse effects when installing the pressure switching means to maintain reliability. It intends to provide a cycle device and a rotary hermetic compressor.

[0012] In order to satisfy the above object, the present invention includes an electric motor section and a plurality of sets of rotary compression mechanism sections housed in a sealed case, and sucks refrigerant into each compression mechanism section from an accumulator through a suction pipe. A refrigerating cycle circuit comprising a rotary hermetic compressor that compresses and discharges through a space inside the hermetic case, and a refrigeration cycle component that communicates with the rotary hermetic compressor through a refrigerant pipe; In rotary type hermetic compressors Pressure switching means for guiding the low-pressure gas to the compression mechanism according to the magnitude of the load to perform normal compression operation or guiding the high-pressure gas to stop the compression operation. The means includes a branch pipe having one end connected to the high-pressure side of the refrigeration cycle via an electromagnetic on-off valve and the other end connected to a suction pipe communicating the accumulator and one compression mechanism, and the accumulator of the suction pipe. An auxiliary suction pipe connected to the end projecting inward, a check valve attached to either the auxiliary suction pipe or the suction pipe to prevent the reverse flow of the refrigerant into the accumulator, and the suction pipe or the auxiliary suction pipe And a guide pipe for attaching and holding to the accumulator.

[0013] In addition, the motor case and a plurality of sets of rotary compression mechanisms connected to the motor unit are accommodated in the sealed case, and suction pipes are respectively provided from the accumulators provided outside the sealed case. In a rotary type hermetic compressor, the refrigerant is sucked into each compression mechanism through the compression mechanism, compressed in each compression mechanism, and then discharged through the space in the sealed case. Connected to the high-pressure side of the refrigeration cycle, the other end connected to a suction pipe communicating with the accumulator and one compression mechanism, and to the end of the suction pipe protruding into the accumulator An auxiliary suction pipe, a check valve that is attached to either the auxiliary suction pipe or the suction pipe and prevents the refrigerant from flowing back into the accumulator, and the suction pipe Ku is provided with a pressure switching hands stage having a guide pipe for mounting holding the auxiliary suction pipe to the accumulator.

Brief Description of Drawings

FIG. 1 is a longitudinal sectional view of a rotary hermetic compressor according to an embodiment of the present invention and a configuration diagram of a refrigeration cycle.

FIG. 2 is an exploded perspective view of a first cylinder and a second cylinder according to the same embodiment.

[FIG. 3A] FIG. 3A is a front view of a section of a second suction pipe according to the embodiment.

FIG. 3B is a side view of the second suction pipe.

[Fig. 4A] Fig. 4A is a partially cutaway view of the second suction pipe and the disassembled check valve and auxiliary suction pipe. It is a front view shown.

[FIG. 4B] FIG. 4B is a partially cutaway front view showing the assembled state of the second suction pipe, check valve and auxiliary suction pipe according to the embodiment.

FIG. 4C is a front view of a part of the branch pipe according to the embodiment.

FIG. 5 is a front view of the sub-assembly according to the same embodiment.

FIG. 6A is an exploded view of the accumulator according to the embodiment.

FIG. 6B is an assembly view of the accumulator according to the embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a cross-sectional view of a rotary hermetic compressor C constituting a refrigeration cycle apparatus and a configuration diagram of a refrigeration cycle circuit R.

First, the rotary hermetic compressor C will be described. 1 is a hermetic case, and a compression mechanism 2 is provided in the lower part of the hermetic case 1 and an electric motor part 3 is provided in the upper part. . The electric motor unit 3 and the compression mechanism unit 2 are connected via a rotating shaft 4.

[0018] For example, a brushless DC synchronous motor (which may be an AC motor or a commercial motor) is used as the motor unit 3, and a stator 5 fixed to the inner surface of the hermetic case 1 and the stator 5 The rotor 6 is arranged with a predetermined gap on the inner side, and the rotating shaft 4 is interposed therebetween. The electric motor unit 3 is electrically connected to an inverter that changes the operating frequency and a control unit that controls the inverter (not shown).

[0019] The compression mechanism section 2 includes a first cylinder 8A and a second cylinder 8B which are disposed below the rotary shaft 4 with an intermediate partition plate 7 interposed therebetween. The first and second cylinders 8A and 8B are set to have different outer shape dimensions and the same inner diameter dimension.

[0020] The outer diameter of the first cylinder 8A is slightly larger than the inner diameter of the sealed case 1, and after being press-fitted into the inner peripheral surface of the sealed case 1, the sealed case 1 can be welded from the outside. Therefore, the positioning is fixed. A main bearing 9 is superimposed on the upper surface of the first cylinder 8A, and is fixed to the cylinder 8A through a mounting bolt together with the valve cover a. A secondary bearing 11 is superimposed on the lower surface of the second cylinder 8B and attached together with the valve cover b. It is fixed to the first cylinder 8A via bolts.

[0021] The outer diameter of the intermediate partition plate 7 and the auxiliary bearing 11 is somewhat larger than the inner diameter of the second cylinder 8B, and the inner diameter position of the cylinder 8B is also deviated from the center of the cylinder. Therefore, a part of the outer periphery of the second cylinder 8B protrudes in the radial direction from the outer diameters of the intermediate partition plate 7 and the auxiliary bearing 11.

On the other hand, the rotating shaft 4 is pivotally supported by the main bearing 9 and the sub bearing 11 at its midpoint and lower end. Further, the rotary shaft 4 penetrates through the cylinders 8A and 8B, and integrally includes two eccentric portions 4a and 4b formed with a phase difference of about 180 °. Each eccentric part 4a, 4b has the same diameter as each other, and is assembled so as to be located in the inner diameter part of each cylinder 8A, 8B. Eccentric rollers 13a and 13b having the same diameter are fitted on the peripheral surfaces of the eccentric parts 4a and 4b.

[0023] The first cylinder 8A and the second cylinder 8B are divided into upper and lower surfaces by an intermediate partition plate 7, a main bearing 9, and a sub-bearing 11, and the first cylinder chamber 14a and the second cylinder are inside. Chamber 14b is formed. The cylinder chambers 14a and 14b are formed to have the same diameter and height, and the eccentric rollers 13a and 13b are accommodated so as to be eccentrically rotatable.

[0024] The height of each eccentric roller 13a, 13b is formed to be the same as the height of each cylinder chamber 14a, 14b. Accordingly, the eccentric rollers 13a and 13b are set to the same excluded volume by rotating eccentrically in the force cylinder chambers 14a and 14b having a phase difference of 180 ° from each other.

FIG. 2 is an exploded perspective view showing the first cylinder 8A and the second cylinder 8B.

Each cylinder 8A, 8B is provided with vane chambers 22a, 22b force S communicating with the cylinder chambers 14a, 14b. In each vane chamber 22a, 22b, a vane 15a, 15b force S is accommodated so as to protrude and retract with respect to the cylinder chamber 14a, 14b. The vane chambers 22a and 22b are integrally connected to vane storage grooves 23a and 23b in which both side surfaces of the vanes 15a and 15b can be slidably moved, and the end portions of the vane storage grooves 23a and 23b. It consists of vertical holes 24a and 24b in which the rear ends of the vanes 15a and 15b are accommodated.

[0026] The first cylinder 8A is provided with a lateral hole 25 for communicating the outer peripheral surface with the vane chamber 22a, and the spring member 26 is accommodated therein. The spring member 26 is interposed between the rear side end surface of the vane 15a and the inner peripheral surface of the sealing case 1, and applies an elastic force (back pressure) to the vane 15a, and this tip edge Is a compression spring that contacts the eccentric roller 13a.

[0027] The vane chamber 22b on the second cylinder 8B side does not contain any members other than the vane 15b. However, as will be described later, the setting environment for the vane chamber 22b and the pressure switch described later will be described. According to the action of the change mechanism (means) K, the tip edge of the vane 15b is brought into contact with and separated from the eccentric roller 13b. The leading edges of the vanes 15a and 15b are formed in a semicircular shape in plan view, and can make line contact with the circumferential walls of the circular eccentric rollers 13a and 13b in plan view regardless of the rotation angle of the eccentric roller 13a. .

[0028] When the eccentric rollers 13a and 13b rotate eccentrically along the inner peripheral walls of the cylinder chambers 14a and 14b, the vanes 15a and 15b reciprocate along the vane housing grooves 23a and 23b, and after the vane. The end portion can act to advance and retract freely from the vertical hole portions 24a and 24b. As described above, due to the relationship between the outer dimensions of the second cylinder 8B and the outer diameters of the intermediate partition plate 7 and the auxiliary bearing 11, a part of the outer shape of the second cylinder 8B is contained in the sealed case 1. Exposed.

The exposed portion of the sealed case 1 is designed to correspond to the vane chamber 22b, so that the rear end portion of the vane chamber 22b and the vane 15b directly receives the pressure in the case. . In particular, since the second cylinder 8B and the vane chamber 22b are fixed structures themselves, there is no influence even if they are subjected to the pressure in the case, but the vane 15b is replaced with the vane chamber 22b. Since it is slidably housed and its rear end is located in the vertical hole 24b of the vane chamber 22b, it receives the pressure in the case directly.

[0029] Further, the tip of the vane 15b faces the second cylinder chamber 14b, and the vane tip receives the pressure in the cylinder chamber 14b. Eventually, the vane 15b is constructed so that the direction of a higher pressure also moves in the direction of a lower pressure in accordance with the magnitude of the pressure applied to the front end portion and the rear end portion.

[0030] Each cylinder 8A, 8B is provided with a mounting hole or screw hole through which the mounting bolt is threaded or screwed, and only the first cylinder 8A has an arc-shaped gas passage hole 27. Is provided. In particular, the vane 15b is eccentrically placed in the vane chamber 22b on the second cylinder 8B side with a force smaller than the differential pressure between the suction pressure guided to the cylinder chamber 14b and the internal pressure of the sealed case 1 guided to the vane chamber 22b. A holding mechanism 10 is provided that urges the roller 13b away from the roller 13b. [0031] The holding mechanism 10 may be a permanent magnet, an electromagnet, or an elastic body. In other words, the holding mechanism 10 is configured to remove the vane 15b from the eccentric roller 13b with a force smaller than the differential pressure between the suction pressure applied to the second cylinder chamber 14b and the pressure inside the sealed case 1 applied to the vane chamber 22b. Energize and hold in the pulling direction.

[0032] By providing a permanent magnet as the holding mechanism 10, the vane 15b is always magnetically attracted with a predetermined force. Alternatively, an electromagnet may be provided instead of the permanent magnet, and magnetic attraction may be performed as necessary. Alternatively, the holding mechanism 10 is a tension spring that is an elastic body. One end of the tension spring may be hooked on the rear end of the vane 15b so that the tension spring is always pulled with a predetermined elastic force.

As shown in FIG. 1 again, a refrigerant pipe 18 serving as a compressed gas discharge section is connected to the upper end of the hermetic case 1 constituting the rotary type hermetic compressor C. The refrigerant pipe 18 is connected to an outdoor heat exchanger 20 through an four-way switching valve 19, an electronic expansion valve 21 as an expansion mechanism, and an accumulator 17 through an indoor heat exchanger 22, and these are connected to the refrigeration cycle circuit R. Is configured.

[0034] To the bottom of the accumulator 17, a first suction pipe 16a and a second suction pipe 16b communicating with the rotary hermetic compressor C are connected. The first suction pipe 16a penetrates the sealed case 1 and the side of the first cylinder 8A, and communicates directly with the first cylinder chamber 14a. The second suction pipe 16b passes through the side of the second cylinder 8B via the hermetic case 1, and communicates directly with the second cylinder chamber 14b.

In the refrigeration cycle circuit R configured as described above, a pressure switching mechanism (means) K for switching the operation of the rotary type hermetic compressor C is provided. The pressure switching mechanism K will be described in detail below.

[0036] This pressure switching mechanism K includes a branch pipe 30, and an electromagnetic on-off valve 31 is provided in the middle. The branch pipe 30 has one end connected to the middle part of the refrigerant pipe 18 communicating with the compressor C and the four-way switching valve 19, and the other end connected to the first branch pipe 3OA connected to the electromagnetic on-off valve 31. One end is connected to the electromagnetic on-off valve 31 and the other end is connected to the second branch pipe 30B connected to the middle portion of the second suction pipe 16b communicating with the second cylinder chamber 14b and the accumulator 17. Power. The middle part of the second branch pipe 30B is connected to the accumulator 1 through the support 32. 7 is mounted and supported.

[0037] The electromagnetic on-off valve 31 is controlled to open and close in response to an electrical signal from the control unit. That is, the refrigerant is conducted from the refrigerant pipe 18 to the second suction pipe 16b via the branch pipe 30, or the refrigerant flow is blocked.

[0038] The other end of the second branch pipe 30B is connected to a connection port 33 provided in the middle of the second suction pipe 16b. The second suction pipe 16b itself is inserted into the guide pipe 34 attached to the accumulator 17, and a connection force such as brazing is applied to the lower end c of the guide pipe 34.

[0039] The auxiliary suction pipe 35, the second suction pipe 16b and the guide pipe 34 in the accumulator 17 penetrating portion are formed perpendicular to each other, and the auxiliary suction pipe 35 is formed in the accumulator 17 with the first suction pipe. It is aligned with 16a and aligned so that the top positions (heights) of each other match.

[0040] A check valve 36 is inserted into the second suction pipe 16b. As will be described later, the check valve 36 allows the refrigerant to flow from the auxiliary suction pipe 35 to the connection port body 33 portion of the second suction pipe 16b and the branch pipe 30, and conversely, the second suction pipe 36 It has a function of blocking the flow of the refrigerant from the pipe 16b into the accumulator 17 through the auxiliary suction pipe 35.

[0041] In this way, pressure is generated between the second suction pipe 16b, the branch pipe 30, the electromagnetic on-off valve 31, the guide pipe 34, the auxiliary suction pipe 35, and the check valve 36 connected to the second cylinder chamber 14b. Switching mechanism K is configured. As will be described later, in accordance with the switching operation of the pressure switching mechanism K, a suction pressure that is a low pressure or a discharge pressure that is a high pressure is guided to the second cylinder chamber 14b provided in the second cylinder 8B. .

[0042] The configuration and assembly of the pressure switching mechanism K, the assembly of the accumulator 17, and the attachment of the pressure switching mechanism K to the accumulator 17 will be further described later.

[0043] Next, the operation of the refrigeration cycle apparatus provided with the above-described rotary hermetic compressor C will be described.

[0044] (1) When normal operation (full capacity operation) is selected:

After closing the solenoid valve 31 that constitutes the pressure switching mechanism K, An operation signal is sent to the motor unit 3, and the rotary shaft 4 is driven to rotate. In the compression mechanism 2, the eccentric rollers 13a and 13b rotate eccentrically in the cylinder chambers 14a and 14b. In the first cylinder 8A, since the vane 15a is always elastically pressed and biased by the spring member 26, the tip edge of the vane 15a is in sliding contact with the peripheral wall of the eccentric roller 13a to move inside the first cylinder chamber 14a. Divide into suction chamber and compression chamber.

[0045] The inner circumferential surface rolling contact position of the cylinder chamber 14a of the eccentric roller 13a and the vane storage groove 23a are aligned, and the space capacity of the cylinder chamber 14a is maximized when the vane 15a is retracted most. The refrigerant gas is sucked into the first cylinder chamber 14d from the accumulator 17 through the first suction pipe 16a and is filled. As the eccentric roller 13a rotates eccentrically, the rolling contact position of the eccentric roller with respect to the inner peripheral surface of the first cylinder chamber 14a moves, and the volume of the compression chamber partitioned by the cylinder chamber 14a decreases. That is, the gas previously introduced into the first cylinder chamber 14a is gradually compressed.

[0046] The rotating shaft 4 is continuously rotated, the compression chamber capacity of the first cylinder chamber 14a is further reduced, the gas is compressed, and when the pressure rises to a predetermined pressure, a discharge valve (not shown) is opened. The high-pressure gas is discharged into the sealed case 1 through the valve cover a and is filled. Then, the refrigerant is discharged from the refrigerant pipe 18 at the upper part of the sealed case and guided to, for example, the outdoor heat exchanger 20 through the four-way switching valve 19.

[0047] On the other hand, since the electromagnetic on-off valve 31 in the pressure switching mechanism K is closed, the discharge pressure (high pressure) is not guided to the second cylinder chamber 14b. The low-pressure evaporative refrigerant separated from the gas and liquid by the accumulator 17 is guided to the second cylinder chamber 14b via the auxiliary suction pipe 35, the check valve 37 and the second suction pipe 16b.

Therefore, the second cylinder chamber 14b is in a suction pressure (low pressure) atmosphere, while the vane chamber 22b is exposed in the sealed case 1 and is under a discharge pressure (high pressure). In the vane 15b, the front end portion is under a low pressure condition and the rear end portion is under a high pressure condition, and there is a differential pressure at the front and rear ends.

[0049] Under the influence of this differential pressure, the tip of the vane 15b is pressed and urged against the eccentric roller 13b against the holding force of the holding mechanism 10. In other words, the vane 15a on the first cylinder chamber 14a side is pressed and urged by the spring member 26 to perform the same compression operation as the compression action. Utility This is also performed in the second cylinder chamber 14b.

[0050] Eventually, in the rotary hermetic compressor C, full capacity operation is performed in which the compression action is performed in both the first cylinder chamber 14a and the second cylinder chamber 14b. The high pressure gas discharged from the sealed case 1 through the refrigerant pipe 18 is led to the outdoor heat exchanger 20 to be condensed and liquefied, adiabatically expanded by the electronic expansion valve 21, and evaporated from the heat exchange air by the indoor heat exchanger 23. Takes out latent heat and performs cooling. Then, the evaporated refrigerant is guided to the accumulator 17, where it is separated into gas and liquid, and again sucked into the cylinder chambers 14a and 14b in the compressor C from the first and second suction pipes 16b and 16b. Circulate.

[0051] (2) When special operation (capability half operation) is selected:

When special operation (operation that halves the compression capacity) is selected, the electromagnetic switching valve 31 of the pressure switching mechanism K is opened. When the motor unit 3 is energized and the rotating shaft 4 is driven to rotate, the first cylinder chamber 14a is compressed as described above, and the high-pressure gas discharged into the sealed case 1 is filled. And high pressure inside the case.

[0052] A part of the high-pressure gas discharged from the refrigerant pipe 18 is diverted to the branch pipe 30, and directly into the second cylinder chamber 14b via the opened electromagnetic on-off valve 31 and the second suction pipe 16b. ,be introduced. A part of the high-pressure refrigerant tries to flow backward from the second suction pipe 16b toward the accumulator 17, but the check valve 36 prevents the reverse flow into the accumulator 17.

[0053] While the second cylinder chamber 14b is in a discharge pressure (high pressure) atmosphere, the vane chamber 22b is in the same situation as the high pressure in the case. Therefore, the vane 15b provided in the second cylinder chamber 14b is affected by the high pressure at both the front and rear ends, and there is no differential pressure at the front and rear ends. The vane 15b does not move at a position away from the outer peripheral surface of the roller 13b and maintains the stopped state, and the compression action in the second cylinder chamber 14b is not performed. Eventually, only the compression action in the first cylinder chamber 14a is effective, and the operation is reduced by half.

[0054] Further, since the inside of the second cylinder chamber 14b is at a high pressure, there is no leakage of compressed gas from the sealed case 1 into the second cylinder chamber 14b, and no loss is caused thereby. . Therefore, it is possible to operate with half the capacity without lowering the compression efficiency. [0055] For example, as compared with the case where the rotational speed is adjusted so that the displacement volume of the compression mechanism section 2 is reduced by half, the above-described half-power operation is employed to achieve the same high rotation speed as that in normal operation. The compression efficiency can be improved by maintaining the pressure.

[0056] The minimum capacity based on the minimum rotational speed determined by the lubricity in the compression mechanism section 2 can be lowered by changing the displacement volume by half, and the minimum capacity can be expanded to finely control the temperature and humidity. A possible refrigeration cycle apparatus can be provided. In the compressor R, the capacity can be varied with a simple structure that simply omits the spring member that biases the base 15b, which is advantageous in terms of cost, is excellent in manufacturability, and provides high efficiency.

[0057] When the maximum capacity is required, a predetermined capacity can be secured by operating two cylinders, and a wide capacity can be secured with one compressor. That is, the required capacity can be easily obtained by controlling the opening / closing of the electromagnetic switching valve 31 in accordance with the operation mode.

Next, the configuration and assembly of the pressure switching mechanism K, the assembly of the accumulator 17, and the attachment of the pressure switching mechanism K to the accumulator 17 will be described in detail.

FIG. 3 is a partial cross-sectional view and bottom view of the second suction pipe 16b, and FIG. 4 is a diagram illustrating the configuration and assembly of the second suction pipe 16b, the auxiliary suction pipe 35, and the check valve 36. FIG. 5 is an enlarged view of the assembled second suction pipe 16b, auxiliary suction pipe 35 and check valve 36, and FIG. 6 is an assembly explanatory view of the accumulator 17 and a partial sectional view of the assembled accumulator 17. is there.

[0060] First, the second suction pipe 16b will be described with reference to FIG.

[0061] The second suction pipe 16b includes a portion connected to the accumulator 17 through the guide pipe 34, and a second casing formed in the second cylinder 8B through the sealing case 1. It consists of a part communicating with the Linda chamber 14b. The part connected to the accumulator 17 is oriented vertically, the part communicating with the second cylinder chamber 14b is oriented horizontally, and the middle part is bent approximately 90 °.

[0062] A bent portion 37 is formed at the 90 ° bent portion of the second suction pipe 16b. The bent portion 37 protrudes downward (distance: H) from the horizontally extending portion and is formed in an R shape, and the connecting port body 33 is provided in the bent portion 37. The position of the connection port 33 is set within a range of 45 ° up and down with respect to the line L drawn in the horizontal direction from the bending center point 0 of the bending portion 37. In other words, the second suction pipe 16b is in a straight state as a processing order, and the connection port body 33 is first formed by, for example, bulging or burring using hydraulic pressure. . As shown only in FIG. 3B, the stepped portion 33d formed at the base end of the connection port body 33 is formed as post-processing after the connection port body 33 is provided.

[0064] Next, the bending portion 37 is formed by applying a bending force to the second suction pipe 16b. At this time, if the connection port body 33 is provided in the above-described position, there is no deformation that does not affect the connection port body 33 when the bent portion 37 is caulked.

[0065] Further, the portion extending in the vertical direction of the second suction pipe 16b is formed as an expanded pipe, and the expanded section 38 is separated from the upper end of the connection port body 33 by at least a distance of (2 mm). It is provided at the position. The pipe expansion part 38 can be formed by bulge caking at the same time as the connection port body 33. If the pipe expansion process is performed in a state of being spaced apart from the above dimensions, the deformation of the pipe expansion process does not reach the connection port body 33. There is no occurrence.

[0066] Such a second suction pipe 16b is provided with the bent portion 37 and attached to the accumulator 17, whereby the attachment position of the accumulator 17 can be lowered by the protrusion H. In other words, the mounting height of the accumulator 17 combined with the compressor C can be lowered to achieve compactness.

[0067] In particular, as shown in FIG. 4A, the check valve 36 includes a ball-shaped valve body 40, a valve holder 41 that accommodates the valve body 40, and the valve holder 41, and a lower end portion of the front seat portion. and a valve casing 42 constituting k. The valve holder 41 is formed by bending a thin plate material, and a valve hole (not shown) is provided at the lower end. The valve body 40 is accommodated in the valve holder 41 so as to be displaceable only in the vertical direction, and the valve hole is opened and closed according to the position.

[0068] The upper end of the valve holder 41 is opened and provided with a piece f bent inward. This piece f is hooked on a latching portion g provided on the side surface of the valve casing 42, and the valve holder 41 is suspended from the valve casing 42. The check valve 36 configured in this way is set so that its outer diameter can be inserted into the expanded portion 38 formed in the second suction pipe 16b in a tight state.

[0069] An upper end portion of the valve housing 42 is provided with a positioning step portion h into which the lower end m of the auxiliary suction pipe 35 that has been expanded is inserted, and a hole portion i is further provided continuously. Accordingly, the valve casing 42 is provided with a hole i passing through the central axis extending from the positioning step h at the upper end to the lower end surface. It is. In FIG. 4A, the horizontal portion of the second suction pipe 16b is illustrated in a straight shape, and the above-described bent portion 37 is omitted.

[0070] As shown in FIG. 4B, a preassembled check valve 36 is accommodated in the expanded pipe portion 38 of the second suction pipe 16b, and the lower end m of the auxiliary suction pipe 35 is connected to the upper end of the expanded pipe section 38. The Specifically, the valve body 40 is inserted into the valve holder 41, the valve holder 41 is hooked on the valve housing 42, the check valve 36 is assembled, and the auxiliary suction is inserted into the positioning step h of the valve housing 42. Insert the lower end m of the pipe 35 that has been expanded.

[0071] In addition, the check valve 36 is also inserted into the upper end of the expanded portion 38 of the second suction pipe 16b. As described above, since the outer diameter of the check valve 36 and the inner diameter of the expanded portion 38 are tightly set, the check valve 36 does not fall straight down to the lower end of the expanded portion 38. When the upper end of the check valve 36 and the upper end of the second suction pipe 16b coincide with each other, the insertion of the check valve 36 into the expanded portion 38 is stopped.

[0072] Thereafter, for example, high-frequency brazing is performed on the connecting portion d where the upper end of the expanded portion 38, the upper end of the check valve 36, and the lower end m of the auxiliary suction pipe 35 are in the same position. Therefore, the upper end of the second suction pipe 16b, the upper end of the check valve 36, and the lower end m of the auxiliary suction pipe 35 are connected to the body.

[0073] In order to prevent thermal deformation due to the brazing process of the valve seat 42 of the valve housing 42 in the check valve 36, cooling is performed by cooling means such as submerging the lower part of the brazing part (connecting part d). However, it is desirable to perform brazing. As a cooling means, water or an inert gas may be flowed inside, other than submerging.

[0074] As shown in FIG. 4C, a second branch pipe 30B is prepared. Most of the second branch pipe 30B is in a vertical state, is inclined obliquely at the lower part, and is bent in the horizontal direction at the lower end part. The horizontal end portion is inserted into a connection port body 33 provided in the second suction pipe 16B and connected by high-frequency brazing.

[0075] At this time, since the step portion 33d is formed in the connection port body 33, the end of the second branch pipe 30B is inserted into the connection port body 33 and abuts against the step portion 33d. There is no misalignment during positioning and brazing of the branch pipe 30B.

[0076] The position of the connection port 33 in the second suction pipe 16b is far away from the valve seat portion k of the check valve 36 that is already incorporated in the expanded pipe portion 38. Branch pipe 30B and connection port The heat effect during brazing with the body 33 is not affected. If there is a thermal effect, it is desirable to perform brazing while flowing an inert gas such as nitrogen gas.

By the above processing and molding, as shown in FIG. 5, the check valve 36 is accommodated in the second suction pipe 16b, and the auxiliary suction pipe 35 and the second branch pipe 30B are connected and integrated as described above. Subassembly 43 is obtained.

[0077] On the other hand, as shown in FIGS. 6A and 6B, the accumulator 17 has an upper cup 17A and a lower cup which are integrally connected after the filter assembly 45 is fitted in a substantially middle portion in the axial direction. It consists of 17B. The upper cup 17A is connected to a refrigerant pipe 18 extending from the compressor C through each refrigeration cycle component device such as an outdoor heat exchanger 20. A first suction pipe 16a and a guide pipe 34 are attached to the lower cup 17B in a state where the first part is inserted into the accumulator 17.

That is, the first suction pipe 16a is formed in a substantially L shape with a vertical portion and a horizontal portion. The straight portion passes through the lower cup 17B, and the upper end extends to the filter assembly 45 in the accumulator 17. The portion protruding downward from the lower cup 17B extends in the horizontal direction toward the compressor C.

[0079] A part of the guide pipe 34 is inserted into the accumulator 17, and the other part projects downward from the accumulator 17. The upper end opening n in the accumulator 17 is bent inward in advance to reduce the opening amount.

[0080] With respect to the accumulator 17, the refrigerant pipe 18, the first suction pipe 16a, and the guide pipe 34 are all brazed along the peripheral surface of the accumulator 17, and the accumulator 17 is sealed. It will not be damaged. This completes the assembly of the accumulator 17.

[0081] Then, the sub-assembly 43 consisting of the second suction pipe 16b and the like is opposed to the lower part of the guide pipe 34 in the assembled accumulator 17, and the upper end of the auxiliary suction pipe 35 is directed to the lower end of the guide pipe 34. Insert the auxiliary suction pipe 35 into the guide pipe 34.

[0082] By moving the sub-assembly 43 upward as it is, the entire auxiliary suction pipe 35 is guided. The auxiliary suction pipe 35 and the brazed position d of the check valve 36 and the second suction pipe 16b come into contact with the narrowed upper end opening n of the guide pipe 34 and inserted into the pipe 34. Be regulated.

[0083] In the accumulator 17, the auxiliary suction pipe 35 stands vertically, and is parallel to the first suction pipe 16a, and the upper end positions thereof substantially coincide with each other. Further, the expanded portion 38 of the second suction pipe 16b is fitted into the guide pipe 34, so that the lower end of the guide pipe 34 and the lower end position of the expanded portion 38 are substantially aligned.

[0084] Then, the position of the sub-assembly 43 is temporarily held, and brazing is performed along the peripheral surface (the portion c in FIG. 1) between the lower end of the guide pipe 34 and the lower end of the expanded portion 38. The second suction pipe 16b (subassembly 43) is attached to the accumulator 17 through the guide pipe 34, and the second suction pipe 16b having the check valve 36 is completely attached to the accumulator 17. . It is desirable that the brazed position and the valve seat k of the check valve 36 be separated from each other by 10 mm or more. In addition, it is desirable to perform brazing while flowing an inert gas such as nitrogen gas inside to prevent oxidation and to cool.

Since the check valve 36 is manufactured separately from the accumulator 17, it is not necessary to be directly affected by heat when the accumulator 17 is assembled. The check valve 36 is connected to the brazed position d between the second suction pipe 16b and the auxiliary suction pipe 35, and to the connection port body 33 provided in the second branch pipe 30B and the second suction pipe 16b. Since it is also away from the brazing position, the thermal effect is small, and it is possible to perform brazing while cooling with a cooling means. Therefore, the assembly accuracy of the check valve 36 is kept high, and it works extremely smoothly.

In the above embodiment, the expanded portion 38 is formed in the second suction pipe 16b to accommodate the check valve 36. However, the auxiliary suction pipe 35 is not limited to this. A configuration in which the check valve is accommodated may be employed. Also, one end of the first branch pipe 30A can be connected to a sealed case.

Furthermore, the present invention is not limited to the above-described embodiments as they are, but can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. So Various inventions can be formed by appropriately combining a plurality of components disclosed in the above-described embodiments.

Industrial applicability

According to the present invention, the range of use can be expanded by switching the operation according to the magnitude of the load, the reverse flow of the refrigerant to the accumulator can be reliably prevented, the refrigeration cycle efficiency can be improved, and the heat can be increased. Effects such as maintaining reliability by preventing adverse effects.

Claims

The scope of the claims

[1] A motor case and a plurality of sets of rotary compression mechanisms connected to the motor unit are accommodated in the sealed case, and suction pipes are respectively provided from the accumulators provided outside the sealed case. The rotary type hermetic compressor that sucks the refrigerant into the respective compression mechanism parts and compresses the refrigerant in each compression mechanism part and then discharges it through the space inside the sealed case, the rotary type hermetic compressor, and the refrigerant pipe. A refrigeration cycle circuit composed of refrigeration cycle components communicated with each other,

Depending on the size of the load, one compression mechanism in the rotary type hermetic compressor may introduce a low pressure gas to perform a normal compression operation, or introduce a high pressure gas to stop the compression operation. Pressure switching means for switching,

The pressure switching means is

A branch pipe having one end connected to the high pressure side of the refrigeration cycle via an electromagnetic on-off valve and the other end connected to a suction pipe communicating the accumulator and one compression mechanism; and An auxiliary suction pipe connected to an end protruding into the accumulator;

A check valve that is attached to either the auxiliary suction pipe or the suction pipe and prevents the refrigerant from flowing back into the accumulator;

A guide pipe for attaching and holding the suction pipe or the auxiliary suction pipe to the accumulator;

A refrigeration cycle apparatus comprising:

[2] The suction pipe includes a connection port body that is bulged to connect the branch pipe, and has a pipe expansion section for mounting the check valve. 2. The refrigeration cycle apparatus according to claim 1, wherein the suction pipe is integrally connected.

[3] The refrigeration cycle apparatus according to claim 1, wherein the suction pipe has a bent portion that projects downward from a connection portion with the compression mechanism portion.

4. The refrigeration cycle apparatus according to claim 2, wherein the suction pipe has a bent portion that is formed to project downward from a connection portion with the compression mechanism portion. A sealed case contains a motor part and a plurality of sets of rotary compression mechanisms connected to the motor part. Refrigerant from the accumulator provided outside the sealed case via a suction pipe. In a rotary type hermetic compressor that sucks the air into each compression mechanism, compresses in each compression mechanism, and then discharges it through the space inside the sealed case. A branch pipe connected at the other end to a suction pipe communicating the accumulator and one compression mechanism, and an auxiliary suction pipe connected to an end of the suction pipe protruding into the accumulator. ,

A check valve which is attached to either the auxiliary suction pipe or the suction pipe and prevents the refrigerant from flowing back into the accumulator;

Pressure switching means having a guide pipe for attaching and holding the suction pipe or auxiliary suction pipe to the accumulator

A rotary hermetic compressor characterized by comprising: