JP4294680B2 - Refrigerant distributor and air conditioner equipped with refrigerant distributor - Google Patents

Description

  The present invention relates to a refrigerant distributor of a heat exchanger for an air conditioner that is applied to, for example, a room air conditioner for home use, and more particularly, to a component that efficiently operates the heat exchanger.

  FIG. 1 is a diagram showing a configuration of a refrigeration cycle of a general household air conditioner. In FIG. 1, 1 is a compressor, 2 is a four-way valve, 3 is a throttle device such as an electric valve, 4 is an indoor heat exchanger, and 5 is an outdoor heat exchanger. In the home air conditioner, by switching the four-way valve 2, the cooling operation (solid arrow) using the indoor heat exchanger 4 as an evaporator and the outdoor heat exchanger 5 as a condenser, and the indoor heat exchanger 4 as a condenser, Heating operation (broken arrows) using the outdoor heat exchanger 5 as an evaporator can be performed.

  For example, in the cooling operation, the high-temperature and high-pressure refrigerant compressed by the compressor 1 passes through the four-way valve 2 and flows into the outdoor heat exchanger 5, and releases and condenses by heat exchange with air. And after carrying out an isoenthalpy expansion | swell by the expansion | swelling apparatus 3, such as a motor operated valve, it flows into the indoor heat exchanger 4 as a gas-liquid two-phase flow in which gas and liquid are mixed at low temperature and low pressure. In the indoor heat exchanger 4, the refrigerant evaporates while increasing the dryness χ from the inlet to the outlet by an endothermic action from the air. And the refrigerant | coolant which came out of the indoor heat exchanger 4 returns to the compressor 1, and comprises a cycle. Incidentally, the dryness χ is a value obtained by dividing the refrigerant gas mass flow rate by the refrigerant total mass flow rate, that is, dryness χ = refrigerant gas mass flow rate / refrigerant total mass flow rate.

  Here, in the indoor heat exchanger 4 acting as an evaporator, the loss due to the flow resistance in the piping constituting the heat exchanger greatly affects the performance degradation as the evaporator. In order to suppress this loss, generally, the indoor heat exchanger 4 is configured to branch in parallel like several paths 11 and 12 and to flow the refrigerant. A refrigerant distributor 31 that distributes the gas-liquid two-phase flow refrigerant to the plurality of paths is required.

  A refrigerant that is a gas-liquid two-phase flow has a density ratio that is several tens of times that of a gas refrigerant and a liquid refrigerant, so that the flow rates are greatly different, the gas-liquid interface is disturbed, and the refrigerant flow becomes unstable. Further, the centrifugal force due to the bending (curved portion) of the connection pipe upstream of the refrigerant distributor and the action of gravity due to the inclination of the inlet pipe also affect the flow variation of the refrigerant. Alternatively, when the curvature of the connection pipe upstream of the refrigerant distributor is small, or when the flow direction changes rapidly, such as a two-way valve, the liquid film is disturbed and the gas phase flows through the flow immediately after that. A flow state with a large number of droplets at the center of the cross section is caused, and the flow variation of the refrigerant is affected in the same manner as described above.

  Furthermore, when the refrigerant flow rate varies in a wide range from a small flow rate to a large flow rate as in an inverter-driven room air conditioner with a variable compressor rotation speed, or when the processing accuracy of the refrigerant distributor 31 varies, It can be said that the distribution of the liquid refrigerant flowing into the distributor 31 in the pipe cross section is greatly different or the refrigerant flow varies greatly.

  For this reason, a path in which the liquid refrigerant contributing to evaporation in the heat exchanger sufficiently flows and a path in which the liquid refrigerant flows only insufficiently and is depleted are generated. When the liquid refrigerant is depleted during the pass, heat exchange cannot be performed in the heat exchangers subsequent to that part, and sufficient performance cannot be exhibited. That is, the refrigerant cannot be fully utilized, and it is necessary to obtain the necessary capacity by increasing the refrigerant flow rate by increasing the refrigerant flow rate by increasing the refrigerant flow rate. In such a case, useless work to be input to the compressor increases, so that it is not possible to save power.

  Furthermore, if the air that has been sufficiently cooled and deprived of latent heat in the path where the liquid refrigerant flows sufficiently and the air that is hardly cooled and remains in the path where the liquid refrigerant is depleted merges downstream of the heat exchanger, Condensation occurs in the air passage, and water drops mix with the air that blows out. Such exposure of the indoor unit causes discomfort for the user.

  Moreover, when the reheat dehumidification system etc. which did not lower the blowing temperature of an indoor unit are employ | adopted, the structure of a refrigerating cycle will become like FIG. That is, the expansion device 33 is provided between the refrigerant paths of the indoor heat exchanger 4, and the refrigerant is decompressed by this expansion device, so that the portions of the paths 21 and 22 are the condenser and the portions of the paths 11 and 12 are the evaporator. The above-mentioned reheat dehumidification method is realized by acting and mixing the respective outlet temperatures. At this time, it is necessary to provide the refrigerant distributor 32 in the middle of the path of the indoor heat exchanger 4. During the cooling operation, the distributor 32 has a higher refrigerant inlet dryness than the refrigerant distributor 31, and therefore, a very small amount of liquid refrigerant must be distributed. Distribution of liquid refrigerant at such a high dryness is a difficult problem because it is more susceptible to the shape of the inlet tube and gravity than the distribution at low dryness.

  Various countermeasures have been considered for such problems related to refrigerant distribution.

For example, when a refrigerant distributor is installed at the inlet of the indoor heat exchanger 4 that acts as an evaporator during cooling operation, the refrigerant inlet dryness χ is relatively small in a general home air conditioner and is around 0.2. . In such a case, as disclosed in Patent Document 1, a swirl component is given to the refrigerant flow, and centrifugal force larger than gravity is applied to reduce the influence of gravity and improve refrigerant distribution. Proposed.

However, a large momentum is required to give the swirl component to the liquid refrigerant, and the necessary momentum cannot be secured when the refrigerant flow rate is small. In addition, when a refrigerant distributor is installed in the middle of the heat exchanger piping, such as when the reheat dehumidification method is adopted, the dryness of the refrigerant is high and the amount of liquid refrigerant to give the swirling component is extremely small. Cannot be generated. For this reason, as disclosed in Patent Document 2, it has been proposed to improve the refrigerant distribution by reducing the influence of gravity by applying a surface tension due to fine grooves.
JP 2000-105026 A JP 2003-014337 A

  As shown in the above-mentioned Patent Document 1, it is possible to reduce the action of gravity due to the inclination of the inlet pipe to some extent by giving a swirling component to the refrigerant flow, but when the refrigerant flow rate is small or the refrigerant dryness of the inlet pipe However, the deviation of the liquid refrigerant in the tube cross-sectional direction could not be reduced.

  On the other hand, as shown in Patent Document 2, by applying surface tension due to fine grooves, liquid refrigerant caused by the influence of gravity or centrifugal force can be used even when the refrigerant flow rate is low or the refrigerant dryness of the inlet pipe is high. Can be reduced.

  However, when the curvature radius of the bending of the connecting pipe upstream of the refrigerant distributor is small, or when the flow direction changes abruptly, such as a two-way valve, the liquid film is disturbed and the gas phase flows immediately after that. A flow state with a large number of droplets in the center of the cross section of the tube is obtained, and the effect of the fine groove cannot be sufficiently obtained. That is, in the case described above, a stable annular flow is not produced in the portion to be distributed, and the distribution ratio cannot be maintained. Furthermore, since the way of biasing the liquid refrigerant varies depending on the flow rate, there has been a problem that the distribution ratio cannot be maintained in a wide flow range such as a small flow rate to a large flow rate.

An object of the present invention is to control the flow of a liquid phase (particularly, a droplet) of a liquid-liquid two-phase flow in the vicinity of the inlet of an inlet pipe having a plurality of grooves on the inner surface of the pipe. However, since it is rectification control of the refrigerant flow of the gas-liquid two-phase flow, it is hereinafter referred to as refrigerant flow rectification means in this application), and its outlet side faces the groove of the inlet pipe. by providing so as to form a space, and even refrigerant flow stream containing droplets gas-liquid two-phase flow flowing into the inlet pipe is disturbed, stable plurality of outlet tubes aims to ensure gas-liquid separator Another object of the present invention is to provide a refrigerant distributor that performs a gas-liquid two-phase flow refrigerant distribution.

In order to solve the above problems, the present invention adopts the following configuration.
A refrigerant distributor comprising: an inlet pipe into which a gas-liquid two-phase refrigerant flow is fed; and a plurality of outlet pipes that distribute the refrigerant flow downstream of the inlet pipe. A cylindrical droplet deflecting means for deflecting droplets contained in the refrigerant flow is provided in the vicinity of the inlet of the inlet pipe so that the outlet side faces the groove of the inlet pipe. A configuration in which a space is formed, and an inner space of the droplet deflecting unit and a space between the outer peripheral portion of the droplet deflecting unit and the inner surface of the inlet pipe form a flow path of the refrigerant flow. And

Further, in the refrigerant distributor, the cylindrical droplet deflecting means forms a taper shape at an upstream end, and the liquid droplet collides with the taper shape so that the flow direction thereof is in the pipe of the inlet pipe. The structure is directed to the surface.

A refrigerant distributor comprising: an inlet pipe into which a gas-liquid two-phase refrigerant flow is fed; and a plurality of outlet pipes that distribute the refrigerant flow downstream of the inlet pipe. A lattice-shaped droplet deflecting means for deflecting droplets contained in the refrigerant flow is provided in the vicinity of the inlet of the inlet pipe, and the outlet side thereof faces the groove of the inlet pipe. The lattice-shaped droplet deflecting means is provided so as to form a space, and has a structure in which the density of the lattice forms a dense structure in the central portion and the density of the lattice forms a coarse structure in the outer peripheral portion.

In the refrigerant distributor, an inner pipe is provided between the inlet pipe and the outlet pipe on the downstream side of the droplet deflecting means , and the inner pipe has an outer diameter smaller than the inner diameter of the inlet pipe. A flange having a hole with a different cross-sectional area is provided between the inner pipe and the outlet pipe .

  According to the present invention, even if the gas-liquid two-phase flow flowing into the inlet pipe having a groove on the inner surface of the pipe has a turbulence including droplets, the gas-liquid separation is ensured and a stable gas-liquid two-phase flow is achieved. The refrigerant flow can be distributed to a plurality of outlet pipes.

  The refrigerant distributor according to the first, second and third embodiments of the present invention will be described in detail below with reference to the drawings.

“First Embodiment”
The refrigerant distributor according to the first embodiment of the present invention will be described below with reference to FIGS. FIG. 3 is a diagram showing an overall configuration of the refrigerant distributor according to the first embodiment of the present invention. In FIG. 3, 40 is a refrigerant flow, 41 is a connecting pipe, 42 is an inlet pipe, 43 is an outlet pipe, 44 is a groove, 45 is an inner pipe, 46 is a flange, 46a is a separated liquid distribution channel, and 46b is The separated liquid distribution channel, 47 is a sectional view of the flange, 60 is a sectional view at the installation position of the rectifying means 61, 61 is the rectifying means in the first embodiment, and 62 is the rectifying means fixing means.

  In FIG. 3, the refrigerant distributor according to the first embodiment of the present invention includes a connection pipe 41 into which a gas-liquid two-phase refrigerant flow 40 flows, an inlet pipe 42, and a plurality of outlet pipes 43. An annular rectifying means 61 is provided between the pipe 41 and the inlet pipe 42, and a plurality of fine spiral grooves 44 are provided on the inner surface of the inlet pipe 42.

  60 is a cross-sectional view taken along the A-A ′ section where the rectifying means 61 is installed. The rectifying means 61 is fixed to the center of the cross section of the inlet pipe 42 by the rectifying means fixing means 62. At this time, the outer diameter of the rectifying means 61 is made smaller than the minimum inner diameter of the inlet pipe 42 so that the liquid film flows between the inner periphery of the connection pipe 41 and the outer periphery of the rectifying means 61. In this embodiment, for example, as shown in FIG. 3, a plurality of protrusions 62 are provided on a part of the outer periphery of the rectifying means 61 to fix the top of the spiral groove and the outer periphery of the rectifying means 61.

  Further, by providing an inner pipe 45 having an outer diameter smaller than the minimum inner diameter of the inlet pipe 42 at the outlet portion of the inlet pipe 42, the double pipe portion X (consisting of the outlet portion of the inlet pipe 42 and the inner pipe 45) is provided. It is composed. 46 is a flange for fixing the inner tube 45, and 47 is a view of the flange cut along a B-B 'section.

  FIG. 4 is a diagram showing a refrigerant flow flow state in a gas-liquid two-phase state flowing into the connection pipe upstream of the inlet pipe in the present embodiment. FIG. 5 is a view showing a refrigerant flow state of a vent (bent pipe) and a two-way valve arranged on the upstream side of the connecting pipe in the present embodiment.

  When the refrigerant distributor according to the present embodiment is used, for example, in an air conditioner, if the upstream side of the connecting pipe 41 is a sufficiently long straight pipe portion, the refrigerant flow in a gas-liquid two-phase state that flows into the connecting pipe 41 The flow state of 40 is as shown in FIG. That is, it is an annular flow (doughnut-shaped flow) in which the liquid phase flows in a film shape on the inner wall of the tube and the gas phase flows in the central portion of the tube cross section. However, in practice, as shown in FIG. 5, a vent (bent pipe) or a two-way valve is often installed upstream of the connection pipe 41. In this case, as shown in FIG. The refrigerant flow in the connecting pipe 41 is brought into a flow state.

  FIG. 5A shows the inside of the vent pipe, and FIG. 5B shows the inside of the two-way valve. In FIG. 5B, the valve body is omitted. FIG. 5 shows a flow from a horizontal flow to a vertical downward direction. As shown in FIG. 5, the refrigerant immediately after passing through a vent, a two-way valve, etc. has a sudden change in the direction of flow, so that the liquid film is disturbed and a large number of droplets are accompanied at the center of the cross section of the pipe through which the gas phase flows. It becomes such a fluid state. When flowing into the inlet pipe in such a flow state, the gas-liquid separation is not performed completely only by the spiral groove 44, and the separation efficiency is lowered and the distribution ratio varies.

  FIG. 6 is a diagram schematically showing a refrigerant flow state by providing a rectifying means in the vicinity of the inlet of the inlet pipe in the first embodiment. In FIG. 6, when the refrigerant flow 40 in the gas-liquid two-phase state passes through the rectifying means 61 and flows into the inlet pipe 42, as shown in FIG. Collides with the upper end of the rectifying means 61. The liquid droplets traveling toward the outer periphery of the tube by this collision directly adhere to the liquid film flowing on the inner wall of the inlet tube 41. Further, the liquid droplets traveling toward the center of the tube cross section join the flow at the center of the tube cross section. The flow in the central portion of the pipe cross section becomes a flow path in which the pipe cross section is reduced from the connecting pipe 41 by the rectifying means 61 (the inner diameter of the rectifying means is smaller than the inner diameter of the connecting pipe 41) and then enlarged by the inlet pipe. Therefore, the flow expands when it flows into the inlet pipe 42 after being contracted inside the rectifying means 61 (see the arrow shown in FIG. 6). The droplet accompanying the flow adheres to the droplet flowing on the inner wall of the inlet tube 42. Therefore, the refrigerant flowing into the inlet pipe 42 becomes a stable annular flow.

  In the rectifying means 61 in the present embodiment, as the tube thickness increases, the amount of droplets adhering to the liquid film increases, but the flow loss increases because of the flow resistance. For this reason, it is necessary to determine the optimal dimension of the rectification means 61 by the dryness of the inlet to which the present embodiment is applied and the pipe shape up to the connection pipe 41. For example, the higher the inlet dryness, the smaller the liquid phase present in the cross section of the tube, so that the liquid film is thinner and the amount of droplets is smaller. That is, the higher the inlet dryness when the present embodiment is applied, the thinner the tube thickness, and the droplets adhere and flow into the inlet pipe 42 without significantly increasing the flow loss due to the rectifying means. The refrigerant to be turned becomes a stable annular flow (doughnut-shaped flow).

  Further, it is necessary to optimally arrange the distance between the rectifying means 61 and the double pipe portion X in accordance with the flow rate range so that the droplets are sufficiently attached downstream of the rectifying means 61. That is, the distance between the rectifying means 61 and the double tube portion X needs to be equal to or greater than the range in which the droplets after passing through the rectifying means adhere to the liquid film. As the flow rate increases, the flow velocity of the gas phase at the center of the cross section of the tube increases, and the flow velocity of the droplets associated therewith increases, so that the range of adhesion to the liquid film after passing through the rectifying device increases. It is necessary to increase the distance to X.

  As described above, when the refrigerant flow 40 that has passed through the rectifying means 61 flows in the inlet pipe 42, the liquid refrigerant is drawn into the groove by the surface tension action at the fine spiral groove 44 provided on the inner surface. It is. Here, since the liquid refrigerant is affected by the surface tension as the gap between the grooves is finer, the liquid refrigerant is preferably a fine groove. Further, the total cross-sectional area in the circumferential direction of the groove portion indicated by oblique lines in FIG. 3 cut along the A-A ′ cross-section must be larger than the volume flow rate of the liquid refrigerant per unit cross-sectional area. If the cross-sectional area of the groove is smaller than the volume flow rate of the liquid refrigerant, the liquid refrigerant overflows from the groove and the effect of the groove is reduced.

  In the refrigerant flow 40, the liquid refrigerant is drawn into the groove in the outer peripheral portion (inner wall of the inlet pipe 42), so that the gas refrigerant flows in the central portion of the cross section of the inlet pipe 42 and the liquid refrigerant flows in the groove 44. It becomes a flow.

  The refrigerant flow 40 that has reached the outlet portion of the inlet pipe 42 flows through the double pipe portion X having the inner pipe 45. At this time, the gas refrigerant in the central portion of the refrigerant flow 40 flows to the inner side X1 of the inner tube 45, the liquid refrigerant in the outer peripheral portion flows to the space X2 sandwiched between the outer periphery of the groove portion 44 and the inner tube 45, and the gas and liquid are mixed. Almost separated (see FIG. 3). This is because the liquid refrigerant is held in the groove 44 due to the surface tension in the groove 44. Therefore, this surface tension can reduce the influence of the inclination of the inlet pipe 42 in the direction of gravity (even if the inlet pipe 42 is not vertically arranged).

  When the pressure loss acting on the liquid refrigerant in the outer peripheral portion X2 of the inner tube 45 is larger than the pressure loss acting on the gas refrigerant in the inner tube 45 inside the X1, the refrigerant accumulates in the space X2 portion. May overflow from the gap X2. In this case, the overflowing liquid refrigerant enters the inside X1 of the inner tube, and the liquid refrigerant and the gas refrigerant cannot be separated successfully. Conversely, when the pressure loss acting on the liquid refrigerant in the outer peripheral portion X2 of the inner tube 45 is smaller than the pressure loss acting on the gas refrigerant inside the inner tube 45 X1, the gas refrigerant enters the space X2 portion, and the liquid refrigerant and gas Separation from the refrigerant does not work.

  Therefore, the outer diameter of the inner pipe 45 is a diameter having a radius from the center of the inlet pipe to the apex of the groove in order to reliably guide the liquid refrigerant flowing in the spiral groove 44 to the gap X2 in the outer peripheral portion. Further, the length of the inner tube 45 is such that the difference in pressure loss between the gas refrigerant flowing through the inside X1 and the liquid refrigerant flowing through the gap X2 between the outer peripheral portions becomes zero. In this way, the inner pipe 45 is installed on the inlet side of the outlet pipe 43 and functions to feed the refrigerant flow obtained by separating the liquid refrigerant and the gas refrigerant by the rectifying means 61 to each outlet pipe while maintaining the state. have. In other words, if the inner pipe is not present, the liquid refrigerant and the gas refrigerant may collide with each other on the inlet side of the outlet pipe and be mixed again, and may not be distributed to the respective outlet pipes at a prescribed gas-liquid ratio.

  In the structure of this embodiment shown in FIG. 3, particularly the flow path hole structure of the flange 46, the liquid and the gas are separated and distributed, so that they can be distributed appropriately. The distribution ratio may be controlled only by the distribution of the liquid refrigerant, and the gas refrigerant is automatically distributed due to the pressure loss of the flow path after the gas-liquid merge. When it is desired to change the distribution ratio, the total area of each of the distribution channels may be changed.

  In FIG. 3, the holes 46a and 46b are the same as each other. The refrigerant flow 40 that has passed through the double pipe portion X having the inner pipe 45 is equally distributed to the outlet pipe 43 from the holes 46 a and 46 b that penetrate the flange 46. In addition, gas refrigerant is distributed to each outlet pipe from the large hole at the center shown in the flange sectional view 47 shown in FIG. In the present embodiment, the liquid refrigerant is distributed by the holes penetrating the flange. However, the flow path of the liquid refrigerant may be configured by separate pipes in which the flow resistance is determined by changing the diameter and length.

  FIG. 7 is a diagram illustrating a refrigerant pipe in which the refrigerant distributor according to the first embodiment is applied to a refrigerant circuit of an indoor heat exchanger of a domestic air conditioner. Next, with reference to FIG. 7, the structure and operation | movement of the indoor heat exchanger of the domestic air conditioner to which the refrigerant distributor which concerns on this embodiment is applied are demonstrated. In FIG. 7, the refrigerant distributors 31 and 32 according to the present embodiment are provided in the middle of the refrigerant pipe.

  In the indoor heat exchanger, in order to exchange heat between air and the refrigerant, heat exchangers 200, 201, and 202 that are bent and disposed are disposed in the casing 114. The heat exchangers 201 and 202 are provided with refrigerant distributors 31 and 32, respectively. Reference numeral 112 denotes a dehumidifying valve for performing reheat dehumidification, and reference numeral 113 denotes a cross-flow fan that supplies an air volume for heat exchange. In each of the heat exchangers 200, 201, and 202, a plurality of fins are stacked in the direction perpendicular to the paper surface, and a plurality of heat transfer tubes pass through the fins. Further, the plurality of heat transfer tubes are connected by, for example, a U-shaped connection tube to form a refrigerant path.

  The refrigerant distributor 31 is a distributor that distributes one path into two paths, and the refrigerant path 310 is distributed by the refrigerant distributor 31 into two paths of refrigerant paths 311 and 312. The refrigerant paths 311 and 312 join after passing through the heat exchangers 200 and 201 to form one path, and are connected to the refrigerant path 320 provided with the dehumidifying valve 112 to form a continuous refrigerant circuit.

  Similarly to the refrigerant distributor 31, the refrigerant distributor 32 is a distributor that distributes one path to two paths, and distributes the refrigerant path 320 into two paths of refrigerant paths 321 and 322. The refrigerant paths 321 and 322 merge after passing through the heat exchanger 202 to form one path, and are connected to the refrigerant path 323 to form a continuous refrigerant circuit. Then, the refrigerant path 323 is guided to an outdoor unit (not shown), and returns to FIG. 7 as the refrigerant path 310 through the compressor, the outdoor heat exchanger, and the pressure reducing means.

  Next, the operation of the indoor heat exchanger will be described. During the cooling operation, the refrigerant flows from an outdoor unit (not shown) into the refrigerant path 310 (in the direction of the solid arrow). The refrigerant that has flowed in is distributed to the two paths of the refrigerant paths 311 and 312 by the refrigerant distributor 31 and exchanges heat with air by the heat exchangers 200 and 201. Thereafter, the refrigerant passes through the refrigerant path 320 and passes through the dehumidifying valve 112 and flows into the refrigerant distributor 32. Then, the refrigerant is again distributed to the refrigerant paths 321 and 322, and exchanges heat with air by the heat exchanger 202.

  When the refrigerant distributor according to this embodiment is applied to the refrigerant distributor 32 shown in FIG. 2, the gas-liquid two-phase refrigerant having a high dryness (around χ = 0.7) passing through the refrigerant path 320 is connected to the connecting pipe 41. The rectification means 61 and the groove portion 44 of the inlet pipe 42 are made into an annular flow, and further separated into gas and liquid by the double pipe portion X (X1, X2) constituted by the inner tube 45. Then, it is equally distributed to the two paths 321 and 322, and heat exchange with the air is performed by the heat exchanger 202.

  At this time, even when the inside of the connection pipe 41 connecting the dehumidifying valve 112 and the refrigerant distributor 32 is short, the liquid film is disturbed, and the liquid droplet flows in the center of the pipe cross section, the liquid droplets adhere to the liquid film by the rectifying means 61. Therefore, the influence of the disturbance of the refrigerant flow is reduced, and a stable annular flow flows into the inlet pipe 42. Next, the refrigerant flow that has flowed into the inlet pipe 42 separates the liquid refrigerant and the gas refrigerant mainly by using surface tension in the space X2 on the groove 44 side and the inner side X1 of the inner pipe 45. The influence of the centrifugal force at the inclination of the gravity direction and the bending (curved portion) of the connecting pipe can be reduced.

  Therefore, even if the refrigerant flow upstream of the inlet pipe having a fine groove is in a turbulent flow state in which droplets are scattered on the gas phase side of the annular flow, the refrigerant is distributed with an optimum distribution ratio in a wide flow range. Can be performed. As a result, it is not necessary to operate the compressor more than necessary, and the electric input is reduced. In addition, problems such as exposure to indoor units due to deterioration of the distribution ratio are eliminated.

  In the above description, the operation of the distributor that divides 1 path into 2 paths has been described as this embodiment, but the same effect can be obtained even when the exit pipe has multiple paths such as 3 paths and 4 paths. . Moreover, although the case where the refrigerant distributor was applied in the middle of the refrigerant pipe of the indoor heat exchanger was described in the present embodiment, the present invention can also be applied to a case where reheat dehumidification is not performed, for example. At this time, since the dehumidification valve becomes unnecessary, even when the dryness of the refrigerant at the inlet is low (when the wetness is high), as in the case of all two passes from the inlet to the outlet of the indoor heat exchanger, By optimizing the outer diameter, thickness, and length of the rectifying means 61, the shape and inner diameter of the groove 44 of the inlet pipe 42, and the outer diameter and thickness of the inner pipe 45 according to the inlet refrigerant state, An effect is obtained.

“Second Embodiment”
The rectifying means in the refrigerant distributor according to the second embodiment of the present invention will be described below with reference to FIG. FIG. 8 is a diagram showing a configuration of another rectifying means in the refrigerant distributor according to the second embodiment of the present invention.

  The rectifying means 71 shown in FIG. 8 is installed at the center of the pipe cross section between the connection pipe 41 into which the gas-liquid two-phase refrigerant flow 40 flows and the inlet pipe 42 (similar to the arrangement shown in FIG. 3). The connection pipe 41, the inlet pipe 42, and the downstream side of the inlet pipe 42 are the same as in the first embodiment. Further, the effect of the gas-liquid separation and the effect when incorporated in the heat exchanger are the same as those of the first embodiment.

  The upstream end portion of the flow of the rectifying means 71 shown in FIG. 8 is tapered from the outer periphery of the tube toward the center of the tube cross section toward the upstream side of the flow. When the refrigerant flow 40 in the gas-liquid two-phase state reaches the rectifying means 71 from the connection pipe 41, it collides with the upstream end of the rectifying means 71 toward the outer periphery of the pipe and adheres to the liquid film flowing on the inner wall of the inlet pipe 41. .

  Further, since the liquid droplet at the center of the tube cross section is a flow path in which the tube cross section is reduced by the rectifying means 71 from the connection pipe 41 and enlarged by the inlet pipe 42, The flow expands when flowing into the inlet pipe 42. The droplet accompanying the flow adheres to the droplet flowing on the inner wall of the inlet tube 41 (a groove is formed on the inner surface of the inlet tube 42 as in the first embodiment). Therefore, the refrigerant flowing into the inlet pipe 42 becomes a stable annular flow.

  In the rectifying means 71 in this embodiment, as the tube thickness increases, the amount of droplets attached increases, but the flow resistance due to the rectifying means increases because of the flow resistance. For this reason, it is necessary to determine the optimal dimension of the rectifying means 71 according to the dryness of the inlet used and the pipe shape up to the connecting pipe 41. For example, as in the first embodiment, the higher the inlet dryness, the smaller the liquid phase present in the cross section of the tube, and thus the thinner the liquid film and the smaller the amount of droplets. That is, the higher the inlet dryness when the present embodiment is applied, the thinner the tube thickness, and the droplets adhere and flow into the inlet pipe 42 without significantly increasing the flow loss due to the rectifying means. The refrigerant is a stable annular flow.

  In addition, the distance between the rectifying unit 71 and the double pipe portion X needs to be optimally arranged according to the flow rate range so that the droplets are sufficiently attached downstream of the rectifying unit 71. That is, the distance between the rectifying means 71 and the double tube portion X needs to be equal to or greater than the range in which the droplets after passing through the rectifying means adhere to the liquid film. As the flow rate increases, the flow velocity of the gas phase at the center of the tube cross section increases and the flow velocity of the droplets accompanying it increases, and the adhesion range to the liquid film after passing through the rectifying device becomes wider. It is necessary to increase the distance to X.

  By configuring the rectifying means 71 as described above, in addition to the merit of the first embodiment, even if the tube thickness is thick, by providing the tapered portion, the gas phase flow at the center of the tube cross section is not greatly disturbed. Since a part of the droplet can be guided to the outer peripheral side, the flow loss due to the rectifying means is reduced, and the refrigerant flow upstream of the inlet pipe is disturbed such that the droplet is scattered on the gas phase side of the annular flow Even in a flowing state, it is possible to perform refrigerant distribution at an optimal distribution ratio in a wide flow rate range.

“Third Embodiment”
The rectifying means in the refrigerant distributor according to the third embodiment of the present invention will be described below with reference to FIG. FIG. 9 is a diagram showing another configuration of the rectifying means in the refrigerant distributor according to the third embodiment of the present invention.

  The rectifying means 81 shown in FIG. 9 is installed on the pipe cross section between the connection pipe 41 and the inlet pipe 42 into which the gas-liquid two-phase refrigerant flow 40 flows. The connection pipe 41, the inlet pipe 42, and the downstream side of the inlet pipe 42 are the same as in the first embodiment. Moreover, the effect of the gas-liquid separation and the effect at the time of incorporating in a heat exchanger are the same as those of the first embodiment.

  The rectifying means in the third embodiment is different from the cylindrical structure shown in FIG. 3 and comprises a lattice-like structure over the entire cross section in the vicinity of the inlet of the inlet pipe 42 provided with a spiral groove on the inner surface of the pipe. In this lattice, the density is formed so that the opening ratio of the central portion of the tube is smaller than that of the outer peripheral portion of the tube. That is, the central part is dense and roughened to the outer peripheral part. Due to the structure of the rectifying means, the flow rate of the gas refrigerant flow containing droplets in the central part of the lattice structure is slow compared to the outer peripheral part due to the dense lattice shape, and collides with the lattice in the central part. The droplets are attracted to the outer peripheral portion having a high flow velocity, and then adhere to the droplets flowing through the spiral groove on the inner surface of the inlet tube. Therefore, the refrigerant flowing into the inlet pipe 42 becomes a stable annular flow.

  The smaller the lattice spacing of the rectifier 81 and the thicker the lattice, the greater the amount of droplets deposited at a large flow rate, but the flow loss due to the rectifier increases. For this reason, it is necessary to determine the density and thickness of the grid depending on the dryness of the inlet used and the flow rate range. Further, it is necessary to take a distance between the rectifying means 81 and the double tube portion X so that the droplets are sufficiently attached downstream of the rectifying means 81 according to the flow rate range to be used.

  For example, as in the first embodiment, the higher the inlet dryness, the smaller the liquid phase present in the cross section of the tube, and thus the thinner the liquid film and the smaller the amount of droplets. That is, the higher the inlet dryness when applying this embodiment, the coarser the density of the lattice, and the droplets adhere to the inlet pipe 42 without significantly increasing the flow loss due to the rectifying means. The refrigerant flowing in becomes a stable annular flow.

  In addition, the distance between the rectifying unit 81 and the double pipe portion X needs to be optimally arranged according to the flow rate range so that the droplets are sufficiently attached downstream of the rectifying unit 81. That is, the distance between the rectifying means 81 and the double tube portion X needs to be equal to or greater than the range in which the droplets after passing through the rectifying means adhere to the liquid film. As the flow rate increases, the flow velocity of the gas phase at the center of the tube cross-section increases, and the flow velocity of the droplets accompanying it increases, so that the range of adhesion to the liquid film after passing through the rectifying device becomes wider. It is necessary to increase the distance to X.

  As shown in FIG. 9, in addition to the merits of the first embodiment by configuring the rectifying means 81, droplets are scattered on the gas phase side of the annular flow of the refrigerant flow upstream of the inlet pipe with a simpler structure. Even in such a turbulent flow state, the refrigerant can be distributed with an optimal distribution ratio in a wide flow rate range.

  As shown in FIG. 9, by providing a coarse and dense grid-like rectification means in the vicinity of the inlet of the inlet pipe, even when a refrigerant flow in which a gas-liquid two-phase flow containing droplets is disturbed is sent, As in the first and second embodiments, a wide flow rate range is possible even when the refrigerant flow upstream of the inlet pipe having a fine groove is in a turbulent flow state in which droplets are scattered on the gas phase side of the annular flow. Thus, refrigerant distribution can be performed with an optimal distribution ratio.

  As described above, the refrigerant distributor according to the embodiment of the present invention has the following configuration, and has functions and effects. That is, in a refrigerant distributor having an inlet pipe and a plurality of outlet pipes branched from the inlet pipe, and having a plurality of fine grooves on the inner surface of the inlet pipe, the inner pipe having an outer diameter smaller than the minimum inner diameter of the inlet pipe A double pipe portion having an inlet pipe and an outlet pipe is provided between the inlet pipe and the outlet pipe so as to be in contact with a plurality of outlet pipe inlets on the inlet pipe outlet side, near the inlet pipe inner wall and near the center. Is a cylindrical (annular) rectifier that is a flow path, or a cylindrical (annular) rectifier that is tapered from the outer periphery of the pipe to the center of the cross section of the pipe at the upstream end of the flow, or a densely packed grid It is characterized in that a rectifying means is provided.

  Since the refrigerant distributor according to the present embodiment has the above-described characteristics, even if the gas-liquid two-phase flow is turbulent, the liquid flow is rectified in the refrigerant flow rectifier configured near the inlet of the inlet pipe. As the droplets pass, the droplets adhere to the liquid film and form a stable annular flow. Furthermore, the gas-liquid two-phase flow that has been circulated by the inner groove of the grooved tube is maintained so that the liquid refrigerant in the groove portion flows to the outer peripheral side by the double tube portion, and the gas refrigerant flowing in the center flows to the inner peripheral side. Form.

  In this way, even if the refrigerant flow upstream of the inlet pipe is in a turbulent flow state where droplets are scattered on the gas phase side of the annular flow, the swirl component by the grooved pipe is dominant and the high flow rate and low dryness are dominant. Liquid refrigerant bias and gravity due to the centrifugal force at the bending (curved part) of the connecting pipe upstream of the inlet pipe not only in the area of high temperature but also in the low flow and high dryness area where the swirling component is not generated by the grooved pipe Thus, refrigerant distribution can be performed with an optimal distribution ratio in a wide flow rate range. As a result, it is not necessary to operate the compressor more than necessary, and the electric input is reduced. In addition, problems such as exposure to indoor units due to deterioration of the distribution ratio are eliminated. Further, by utilizing the action of separating the gas and liquid, the refrigerant distributor according to the present embodiment is applied to an air conditioner, so that only the liquid refrigerant is mainly collected by the refrigerant distributor and introduced into the indoor heat exchanger. If the gas refrigerant is returned to the compressor without passing through the indoor heat exchanger, the air conditioner is operated with high efficiency and reliability (because no excess liquid is mixed into the compressor). Can do.

It is a figure which shows the structure of the refrigerating cycle of a general household air conditioner. It is a figure which shows the structure of the refrigerating cycle corresponding to the reheat dehumidification of a general household air conditioner. It is a figure showing the whole refrigerant distributor composition concerning a 1st embodiment of the present invention. It is a figure which shows the refrigerant | coolant flow flow state of the gas-liquid two-phase state which flows in into the connecting pipe of the inlet pipe upstream in 1st Embodiment. It is a figure which shows the refrigerant | coolant flow flow state of the vent (bending pipe | tube) arrange | positioned in the connection pipe upstream in 1st Embodiment, and a two-way valve. It is a figure which represents typically the refrigerant | coolant flow state by providing a rectification | straightening means in the entrance vicinity of the inlet pipe in 1st Embodiment. It is a figure which shows the refrigerant | coolant piping which applied the refrigerant distributor which concerns on 1st Embodiment to the refrigerant circuit of the indoor heat exchanger of a domestic air conditioner. It is a figure which shows the other structure of the rectification | straightening means in the refrigerant distributor which concerns on the 2nd Embodiment of this invention. It is a figure which shows another structure of the rectification | straightening means in the refrigerant distributor which concerns on the 3rd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Compressor 2 Four-way valve 3 Throttling devices, such as a motor operated valve 4 Indoor heat exchanger 5 Outdoor heat exchanger 11, 12, 21, 22 Refrigerant path 31, 32 Refrigerant distributor 40 Refrigerant flow 41 Connection pipe 42 Inlet pipe 43 Outlet pipe 44 Groove 45 Inner tube 46 Flange 46a Separated liquid distribution flow path 46b Separated liquid distribution flow path 47 Cross sectional view of the flange 60 Cross sectional view at the installation position of the rectifying means 61 61 Rectifying means 62 in the first embodiment Rectifying means fixing means 71 Rectifying means in the second embodiment 81 Rectifying means in the third embodiment 112 Dehumidifying valve 113 Cross-flow fan 114 Indoor unit casing 200, 201, 202 Heat exchanger 310, 311, 312, 320, 321 , 322,323 Refrigerant path

Claims (5)

In a refrigerant distributor comprising an inlet pipe into which a gas-liquid two-phase refrigerant flow is sent, and a plurality of outlet pipes that distribute the refrigerant flow downstream of the inlet pipe,
The inlet pipe has a plurality of grooves so that the liquid refrigerant flows on the inner surface of the pipe,
In the vicinity of the inlet of the inlet pipe, a cylindrical liquid droplet deflecting means for deflecting liquid droplets contained in the refrigerant flow is provided so that the outlet side faces the groove of the inlet pipe and forms a space ,
A refrigerant distributor, wherein an inner space of the droplet deflecting unit and a space between an outer peripheral portion of the droplet deflecting unit and an inner surface of the inlet pipe form a flow path of the refrigerant flow. In claim 1,
The cylindrical droplet deflecting means forms a tapered shape at the upstream end,
The refrigerant distributor is characterized in that, when the droplet collides with the tapered shape, the flow direction thereof is directed toward the inner surface of the inlet pipe. In a refrigerant distributor comprising an inlet pipe into which a gas-liquid two-phase refrigerant flow is sent, and a plurality of outlet pipes that distribute the refrigerant flow downstream of the inlet pipe,
The inlet pipe has a plurality of grooves so that the liquid refrigerant flows on the inner surface of the pipe,
In the vicinity of the inlet of the inlet pipe, a lattice-like liquid droplet deflecting means for deflecting liquid droplets contained in the refrigerant flow is provided so that the outlet side thereof faces the groove of the inlet pipe and forms a space ,
The lattice-shaped droplet deflecting means is characterized in that the density of the lattice forms a dense structure in the central portion, and the density of the lattice forms a coarse structure in the outer peripheral portion. In claim 1, 2 or 3,
On the downstream side of the droplet deflecting means, an inner pipe is provided between the inlet pipe and the outlet pipe,
The inner tube has an outer diameter smaller than the inner diameter of the inlet tube;
A refrigerant distributor, wherein a flange with a hole having a different cross-sectional area is provided between the inner pipe and the outlet pipe .   An air conditioner, wherein the refrigerant distributor according to claim 1, 2, 3, or 4 is applied to a refrigerant path of an indoor heat exchanger.

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