JP2006112668A - Outdoor unit for multi-chamber type air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an outdoor unit for a multi-chamber type air conditioner comprising a distributor for evenly and uniformly distributing a lubricant from an oil separator when the lubricant is distributed to a plurality of flow channels to be circulated to compressors. <P>SOLUTION: A branch portion 1 is composed of a strainer portion 2 having a lubricant inflow opening 2a at its one end, a mesh screen 2c inside, and an outflow opening at the other end in a state of being successively formed, a connection pipe portion 3 connected with the outflow opening 2b of the strainer portion 2 at its one end, and the distributor 4 connected with the other end of the connection pipe portion 3 at its inflow opening 4a, and having a triangular portion 4d where a plurality of outflow passages 4c for allowing the lubricant to flow out at a prescribed angle to the advancing direction of the flowing-in lubricant are crossed. The distributor 4 is formed into the shape of cylindrical column, and has an inflow opening 4a at its one end, and outflow openings 4b of the plurality of outflow passages 4c at the other end in a state of being circularly arranged at equal intervals. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an outdoor unit including a plurality of compressors, and more particularly, to a lubricant distributor for a compressor.

  Conventionally, an outdoor unit of a multi-room type air conditioner has constituted a refrigerant circuit shown in the block diagram of FIG. FIG. 3A is a view showing a refrigerant circuit, and FIG. 3B is an enlarged view of a main part showing a flow divider of the refrigerant circuit.

  As shown in FIG. 3A, the outdoor unit of the multi-room air conditioner includes a first compressor 81a, a second compressor 81b, a third compressor 81c arranged in parallel, and these first compressors. Four-way valve 82 provided on the refrigerant discharge side of the third compressor 81c from 81a, a plurality of outdoor heat exchangers 84a and 84b, a receiver tank 85, and refrigerant suction of the third compressor 81c from the first compressor 81a A refrigerant circuit is constituted by an accumulator 86 provided on the side. Each of the receiver tank 85 and the four-way valve 82 is provided with a connection valve 97 connected to a refrigerant circuit of an indoor unit (not shown).

  An oil separator 87 is provided between the first compressor 81a to the third compressor 81c and the four-way valve 82, and a pipe from the oil take-out side of the oil separator 87 is branched by a branching portion 88 described later. The first compressor oil return bypass 91 and the second compressor oil are connected to the refrigerant suction sides of the first compressor 81a, the second compressor 81b, and the third compressor 81c via the electromagnetic opening / closing valve 89 and the capillary tube 90, respectively. The return bypass 92 and the third compressor oil return bypass 93 are connected to each other.

  Similarly, the pipe from the oil take-out side of the oil separator 87 is branched at the branching portion 88 and connected to the refrigerant suction side of the accumulator 86 through the electromagnetic open / close valve 89 and the capillary tube 90 via the low pressure-high pressure bypass 94. Yes.

  As shown in FIG. 3B, the branch portion 88 is configured by a branch pipe 95 provided immediately before the electromagnetic on-off valve 89 (see, for example, Patent Document 1).

  With the above refrigerant circuit, the refrigerant discharged from each compressor 81a, 81b, 81c merges into one refrigerant pipe, and is separated into lubricating oil and refrigerant leaked from the compressor by the oil separator 87, and further separated. Among the refrigerants, the gas refrigerant is guided to the four-way valve 82.

  On the other hand, the lubricating oil separated by the oil separator 87 is divided into four at the branching portion 88, the flow rate is adjusted by the electromagnetic on-off valve 89, and the pressure is reduced by the capillary tube 90. Are sucked into the compressors 81a, 81b, 81c, respectively, and the remaining one flows into the accumulator 86.

  The branch portion 88 is actually installed substantially vertically so that the lubricating oil flows from the bottom to the top. This is because if the branching portion 88 is installed obliquely, the lubricating oil in the pipe is biased, and when the branching portion 88 is split, the branching portion 88 is diverted while being biased.

  As described above, the lubricating oil leaked from the compressor is collected before flowing out to the indoor unit side, and control is performed so that the lubricating oil does not run short regardless of the operating state of each compressor.

  By the way, the structure shown in sectional drawing of FIG. 4 is disclosed as a divider | distributor which divides | segments a refrigerant | coolant into plurality. The distributor 70 has a shape in which a bottle-shaped gathering portion 79 having an opening on one side is inverted, and a connection pipe 73 into which refrigerant flows is connected to the opening, and corresponds to the bottom of the bin. The part is provided with three holes. A thin tube 78 through which the refrigerant flows out is inserted and fixed in each hole.

  Further, a test tube-shaped filter 71 made of a metal mesh is arranged from the opening toward the inside of the collecting portion 79, and the refrigerant flowing in from the connection pipe 73 escapes from the gap of the mesh of the filter 71 to the narrow pipe 78. It comes to leak.

  Usually, the refrigerant is in the form of gas or liquid, or a mixture thereof, and when the refrigerant is divided, the gas and the liquid need to be divided at the same ratio. In this distributor 70, the refrigerant is diffused throughout the filter 71 due to minute passage resistance when the gas or liquid refrigerant passes through the fine mesh of the filter 71, and the diffused refrigerant having a uniform density is diffused. (See, for example, Patent Document 2).

However, in the T-shaped branch pipe 95 shown in FIG. 3 (B), the lubricating oil that has flowed in tends to go straight as it is and flows out from the outlet at the end of straight running, and there is a problem that uniform diversion is not possible. It was.
Moreover, when it is going to apply the structure of the divider | distributor 70 used with a refrigerant | coolant to the branch part 88 of lubricating oil, there exist the following problems. That is, the lubricating oil may have a flow velocity that is about 10 times faster than that of the refrigerant gas, and it is assumed that the thin tubes 78 arranged in a horizontal row have a large resistance to the lubricating oil flow and are not evenly divided.

  Further, since the viscosity of the lubricating oil when the temperature is low, such as when starting the compressor in winter, is higher than that of the refrigerant, when passing through the filter 71, only a partial mesh surface of the filter 71 may pass. When the distance between the filter 71 and the narrow tube 78 is short, the density becomes uneven. Lubricating oil of this uneven density is applied to a specific thin tube 78, for example, the central thin tube 78 among the thin tubes 78 arranged in a horizontal row. The case where it concentrates is assumed.

JP 2004-44930 A (page 3-4, FIG. 1) Japanese Utility Model Publication No. 58-145464 (page 8-9, FIG. 5)

  The present invention solves the above-described problems, and a multi-chamber air provided with a distributor that can evenly distribute without uneven distribution when lubricating oil from an oil separator is distributed to a plurality of flow paths and returned to a compressor. It aims at providing the outdoor unit of a harmony machine.

In order to solve the above-described problems, the present invention provides an oil separator connected to the refrigerant discharge side of a plurality of compressors connected in parallel, and a plurality of flow paths for lubricating oil of the compressor separated by the oil separator. In an outdoor unit of a multi-room air conditioner, comprising: a branch part that distributes to the refrigerant; and an oil return bypass that recirculates to the refrigerant suction side of the plurality of compressors through the branch part,
The branch part includes a strainer part in which a lubricating oil inlet is arranged at one end, a mesh-like screen inside, and an outlet at the other end, and a connecting pipe part having one end connected to the outlet of the strainer part. And an inflow port connected to the other end of the connecting pipe portion, and a shunt that includes a plurality of outflow passages through which the lubricating oil flows out at a predetermined angle with respect to the traveling direction of the inflowing lubricating oil. .

  Further, the flow divider is formed in a cylindrical shape, and the inflow port is arranged at one end, and the outflow ports of the plurality of outflow paths are arranged at the same circumference and at equal intervals.

  Further, the shunt is extended to form the connecting pipe part, or the strainer part is extended to form the connecting pipe part, or the shunt, the connecting pipe part, and the strainer part are integrated. Form.

By using the above means, according to the outdoor unit of the multi-room air conditioner according to the present invention,
In the invention according to claim 1, the branching portion includes a strainer portion in which a lubricating oil inlet is disposed at one end, a mesh-like screen is disposed inside, and an outlet is disposed at the other end. Is connected to the other end of the connecting pipe part, and a shunt where a plurality of outflow passages for flowing out the lubricating oil intersect at a predetermined angle with respect to the traveling direction of the flowing lubricating oil. By constructing with
The resistance of the lubricating oil flowing at a high speed from the inlet of the strainer portion can be reduced, and the lubricating oil can be evenly divided. Furthermore, since the copper pipes connected thereto are dispersed without being bundled due to the inclination of the outflow path, a space is created at the base of the copper pipe when brazing, and workability is improved.

  In the invention according to claim 2, the flow divider is formed in a cylindrical shape, the inlet is provided at one end, and the outlets of the plurality of outflow passages are provided at the other end in the same circumference and at equal intervals. Lubricating oil can be evenly divided.

  In the invention according to claim 3, the shunt is extended to form a connecting pipe part, the strainer part is extended to form a connecting pipe part, or the shunt, the connecting pipe part, and the strainer part are formed integrally. By doing so, man-hours can be reduced when assembling the flow divider. Furthermore, since there is no step with the connecting pipe portion at each connection location, resistance to the flow of the lubricating oil can be reduced.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail as examples based on the attached drawings. In addition, the same number is attached | subjected about the part demonstrated by background art, and detailed description is abbreviate | omitted.

  An outdoor unit of a multi-room air conditioner according to the present invention constitutes a refrigerant circuit shown in the block diagram of FIG. Of the refrigerant circuit described in the background art, the branch portion 88 is replaced with the branch portion 1 according to the present invention.

  As shown in FIG. 1, the outdoor unit of the multi-room air conditioner includes a first compressor 81a, a second compressor 81b, a third compressor 81c arranged in parallel, and a first compressor 81a to a first compressor 81a. A four-way valve 82 provided on the refrigerant discharge side of the three compressor 81c, a plurality of outdoor heat exchangers 84a and 84b, a receiver tank 85, and a refrigerant suction side of the third compressor 81c from the first compressor 81a. The accumulator 86 thus formed constitutes a refrigerant circuit. Each of the receiver tank 85 and the four-way valve 82 is provided with a connection valve 97 connected to a refrigerant circuit of an indoor unit (not shown).

  An oil separator 87 is provided between the first compressor 81a to the third compressor 81c and the four-way valve 82, and a pipe from the oil take-out side of the oil separator 87 is branched at a branching section 1 described later. The first compressor oil return bypass 91 and the second compressor oil are connected to the refrigerant suction sides of the first compressor 81a, the second compressor 81b, and the third compressor 81c via the electromagnetic opening / closing valve 89 and the capillary tube 90, respectively. The return bypass 92 and the third compressor oil return bypass 93 are connected to each other.

  Similarly, the pipe from the oil take-out side of the oil separator 87 is branched at the branching section 1 and connected to the refrigerant suction side of the accumulator 86 via the electromagnetic opening / closing valve 89 and the capillary tube 90 via the low-pressure-high-pressure bypass 94. Yes.

  FIG. 2 is a sectional view showing the structure of the branch 1 according to the present invention. This branch part 1 includes a strainer part 2 having a lubricating oil inlet 2 a at the lower part, a connecting pipe part 3 having one end connected to the outlet 2 b of the strainer part 2, and the other end of the connecting pipe part 3. It is comprised with the distributor 4 which is a connected shunt.

  The strainer portion 2 has a cylindrical shape made of a metal whose center portion swells, and a test tube screen 2c is disposed near the center of the strainer portion 2 with the bottom portion facing the outflow side of the lubricating oil. The screen 2c is metallic and has a gap of 100 mesh, and the lubricating oil passing therethrough is divided into particles of several tens of microns and also has a function of removing fine dust (metal particles) leaking from the compressor. Yes. As a result of the experiment, it was confirmed that the fineness of the screen 2c of about 60 to 100 mesh is most suitable for the formation of lubricating oil particles.

  The connecting pipe portion 3 is a copper pipe having an outer diameter of about 9 mm. One end is fixed to the inlet 4 a of the distributor 4 and the other end is fixed to the outlet 2 b of the strainer portion 2 by brazing.

  The distributor 4 includes one inflow port 4a at one end and four outflow ports 4b at the other end, which are in communication with each other. In addition, an outflow passage 4 c communicating with the outflow port 4 b is provided, and a center line between the outflow port 4 b and the outflow passage 4 c is inclined at an angle θ with respect to the center line of the branch portion 1. The angle θ is preferably as small as possible in terms of fluid dynamics, but considering the workability of a copper pipe (not shown) connected to the outlet 4b, θ is a practical angle of about 15 °.

  The outlet 4b is arranged at an equal angle in the circumferential direction when viewed from the upper surface of the distributor 4. Therefore, a triangular pyramid-shaped triangular portion 4d is formed at a place where the outflow passage 4c joins.

  Since the apex of the triangular portion 4d is directed toward the inlet 4a of the distributor 4, the resistance of the lubricating oil flowing in from the inlet 4a at high speed can be reduced. In addition, the copper pipes connected thereto are dispersed without being bundled due to the inclination of the outlet 4b and the outflow passage 4c, so that a space is created at the base of the copper pipe when brazing, and workability is improved. .

Another feature of the present application is that the problem described in the background art has solved the problem that the lubricating oil having a low temperature has an uneven density when the distance between the filter and the thin tube is short.
As described above, when the lubricating oil is at a high temperature, the smaller the distance d between the screen 2c and the apex of the triangular portion 4d that is the branching point, the more equally the flow can be divided. However, when starting up the compressor in winter, the viscosity of the lubricating oil is high and the flow rate is slow, so that it tends to be dense at the bottom (outflow destination direction) of the screen 2c.

Therefore, in the present invention, by setting the distance d to a predetermined value, both the case where the temperature of the lubricating oil is high and the case where the temperature is low are made compatible, and in both cases, the lubricating oil can be evenly distributed.
When the lubricating oil is at a low speed, the particles of the lubricating oil that have escaped from the bottom of the screen 2c are in a dense state, but toward the inlet 4a of the distributor 4 while being slowly stirred by the vortex generated when leaving the screen 2c. Flowing.

Accordingly, if the distance d over which the slowly stirred lubricating oil particles move has a certain length, homogenization is promoted because the stirring time is long. However, if the distance d is too long, the lubricating oil particles start to combine and return to the state before exiting the screen 2c.
In the experiment, it was found that the distance d = about 100 mm to 50 mm is most practical in consideration of the flow velocity and temperature of the lubricating oil, and the distance d is set to 60 mm in the branch part 1 of FIG.

  As described above, the branch part 1 is composed of the strainer part 2, the connecting pipe part 3, and the distributor 4, but the distributor 4 and the connecting pipe part 3 or the strainer part 2 and the connecting pipe part 3 are connected. Alternatively, the assembly man-hour can be reduced by integrally forming the distributor 4, the connecting pipe portion 3, and the strainer portion 2. Moreover, since there is no level difference with the connection pipe portion 3 at each connection location, resistance to the flow of the lubricating oil can be reduced.

It is a block diagram which shows the refrigerant circuit of the outdoor unit of the multi-room type air conditioner by this invention. It is sectional drawing which shows the structure of the branch part by this invention. It is a block diagram which shows the outdoor unit of the conventional multi-room type air conditioner, (A) is a figure which shows a refrigerant circuit, (B) is a principal part enlarged view which shows the shunt of a refrigerant circuit. . It is sectional drawing of the divider | distributor currently used conventionally and which divides a refrigerant into plurality.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Branch part 2 Strainer part 2a Inlet 2b Outlet 2c Screen 3 Connection pipe part 4 Distributor (divider)
4a Inlet 4b Outlet 4c Outlet 4d Triangle part 70 Distributor 71 Filter 73 Connection pipe 78 Narrow pipe 79 Aggregation part 81a First compressor 81b Second compressor 81c Third compressor 82 Four-way valve 84a Outdoor heat exchanger 85 Receiver Tank 86 Accumulator 87 Oil separator 88 Branch part 89 Electromagnetic switching valve 90 Capillary tube 91 First compressor oil return bypass 92 Second compressor oil return bypass 93 Third compressor oil return bypass 94 Low pressure-high pressure bypass 95 Branch pipe 97 Connection valve

Claims (3)

An oil separator connected to the refrigerant discharge side of a plurality of compressors connected in parallel, a branching part for distributing lubricating oil of the compressor separated by the oil separator to a plurality of flow paths, and the branching part In the outdoor unit of the multi-room air conditioner provided with an oil return bypass that recirculates to the refrigerant suction side of the plurality of compressors through
The branch part includes a strainer part in which a lubricating oil inlet is arranged at one end, a mesh-like screen inside, and an outlet at the other end, and a connecting pipe part having one end connected to the outlet of the strainer part. And an inflow port connected to the other end of the connecting pipe portion, and a shunt that includes a plurality of outflow passages through which the lubricating oil flows out at a predetermined angle with respect to the traveling direction of the inflowing lubricating oil. An outdoor unit of a multi-room type air conditioner characterized by that.   The diverter is formed in a cylindrical shape, and the inflow port is arranged at one end, and the outflow ports of the plurality of outflow passages are arranged at the same circumference and at equal intervals. The outdoor unit of the multi-room air conditioner according to Item 1.   The shunt is extended to form the connecting pipe part, the strainer part is extended to form the connecting pipe part, or the shunt, the connecting pipe part, and the strainer part are integrally formed. The outdoor unit for a multi-room air conditioner according to claim 1, wherein the outdoor unit is a multi-room air conditioner.

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