JP2008121984A - Heat exchanger unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem wherein an operation mode disabling maximum capacity exhibition of a heat exchanger exists due to a coolant flowing only to a specific line although the coolant is in an overaccumulated state in the heat exchanger because the amount of heat exchanger differs by the presence/absence of condensed water sticking to the surface of the heat exchanger. <P>SOLUTION: The coolant flows to either the balance tube 15a or balance tube 15b side by a branch unit 14 having an opening/closing device. The passage resistance of the balance tubes can thereby be changed according to each operating state to improve overaccumulation of the coolant in the heat exchanger and the flow of the coolant only to the specific line. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a fin-and-tube type heat exchanger for exchanging heat between a refrigerant and a fluid such as air.

  Conventionally, this type of heat exchanger performs heat exchange by laminating fins and penetrating the heat transfer tube, and exchanging heat energy of the refrigerant passing through the heat transfer tube with air near the fins through the fins. .

FIG. 3 shows a conventional heat exchanger unit. In FIG. 3, a heat exchanger 11, a blower 12 that blows air to the heat exchanger 11, a drain pan 13 that receives condensed water when the heat exchanger 11 is an evaporator for cooling operation, and a pressure reducing device during the cooling operation are provided. The branch unit 14 that distributes the refrigerant depressurized in step 1 to the heat exchanger 11, and the balance pipe 15 that flows from the branch unit 14 to each heat transfer tube 11 a of the heat exchanger 11 are connected to the connection port 11 b that serves as the inlet and serves as the outlet. A bed 11d is connected to the connection port 11c. And as a means to improve the heat exchange performance, the density of the fins of the heat exchanger 11 and the configuration of the heat transfer tube 11a are changed (not shown) in accordance with the installation position of the blower 12 and the passing air speed of the heat exchanger 11 (not shown). The wind speed distribution in the exchanger 11 is adjusted to improve the heat exchange performance (see, for example, Patent Document 1).
JP-A-1-28494

  However, in the conventional configuration, when the heat exchanger unit is used as an evaporator, the condensed water condensed when air passes through the heat exchanger tends to accumulate between the fins at the bottom of the heat exchanger, The water level of the drain pan rises depending on the installation position of the outlet for discharging condensed water, and the lower part of the heat exchanger may be immersed in the drain water. In such a case, the amount of heat exchange between the fins and air is smaller than in other locations, and the evaporating ability is greatly different between the heat transfer tube at the bottom and the other heat transfer tubes, and the refrigerant flows in a concentrated manner at the bottom. In order to reduce the amount of refrigerant flowing into the heat transfer tube at the bottom of such a heat exchanger, the flow resistance of the balance tube is increased, or the number of turns of the heat transfer tube is increased to reduce the resistance in the heat exchanger. However, if the heat exchanger unit is used as a condenser, the refrigerant will accumulate too much in the adjusted heat transfer tube, resulting in the problem of reduced condenser capacity and increased power consumption. Had.

  The present invention solves the above-described conventional problems, and in the heat exchanger that is selectively used as an evaporator or a condenser, when used as an evaporator, for example, the influence of the configuration in consideration of the influence of condensed water at the bottom, etc. It is an object of the present invention to provide a heat exchange unit that suppresses the reduction in condenser capacity or increase in power consumption without being received when used as a condenser.

  In order to solve the above-mentioned conventional problems, the heat exchanger unit of the present invention opens and closes the branch unit to use a balance tube properly depending on whether the heat exchanger is used as a condenser or an evaporator. A device is provided.

  As a result, when the heat exchanger is used as an evaporator, it is not necessary to increase the flow resistance of the heat transfer tube and the balance tube at the bottom of the heat exchanger, so the indoor heat exchanger unit is used as a condenser. Thus, the refrigerant that has been generated in the heat exchanger is not excessively accumulated in the heat exchanger, and heating capacity can be improved and power consumption can be reduced.

  The heat exchanger unit of the present invention can not only prevent the ability of the heat exchanger unit from being lowered due to the presence or absence of condensed water at the bottom of the heat exchanger caused by the operating state, but also can reduce power consumption.

  The heat exchanger unit of the first invention includes a heat exchanger, a branch unit that distributes the refrigerant to each heat transfer tube path of the heat exchanger, a balance pipe connected to the branch portion and the heat exchanger, and heat exchange A heat exchanger blower for the heat exchanger and a drain pan for storing condensate generated in the heat exchanger, and according to the operating condition of the air conditioning, install a switching device in the branch unit and use a balance tube separately for each heat transfer tube path Since the amount of refrigerant flowing in can be adjusted, it is possible to improve the capacity and reduce power consumption when used as a condenser without being affected by the condensed water at the bottom of the heat exchanger that occurs when used as an evaporator. .

  According to the second aspect of the present invention, since the amount of refrigerant flowing into each heat transfer tube path can be adjusted by providing an opening / closing device in the balance tube and using the balance tube properly, the condensation is not affected by the condensed water at the bottom of the heat exchanger. Capability can be improved and power consumption can be reduced. In addition, when there are few routes for adjusting the amount of refrigerant, the material cost can be reduced. Further, since the accommodation space for the balance pipe and the branch unit is reduced, the product can be downsized and the design flexibility can be improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a schematic diagram of a heat exchanger unit according to Embodiment 1 of the present invention. In FIG. 1, a heat exchanger 11, a blower 12 that blows air to the heat exchanger 11, and a drain pan 13 that receives condensed water condensed when the heat exchanger 11 is an evaporator for cooling operation are provided. A plurality of heat transfer tube paths 11a are configured by connecting heat transfer tubes to the heat exchanger 11, and a branch unit 14a that distributes the refrigerant to these heat transfer tube paths 11a during cooling operation serves as an inlet via the balance tube 15a It is connected to the mouth 11b. The balance tube 15a has a configuration in which the flow rate of the refrigerant is adjusted according to the cooling operation state, and varies slightly depending on the heat transfer tube path 11a. The branch unit 14a is provided with a check valve 16a only in the direction of flowing into the heat exchanger 11 to prevent the reverse flow of the refrigerant during the heating operation.

  The branch unit 14b is connected via a balance pipe 15b connected in parallel with the balance pipe 15a. The balance pipe 15b collects the flow of the refrigerant during the heating operation, and does not particularly adjust the flow rate, and is configured such that the refrigerant flows evenly through the heat transfer pipe paths 11a. And the check valve 16b which prevents the flow of the refrigerant | coolant at the time of air_conditionaing | cooling operation is provided in the branch unit 14b.

  The branch unit 14a and the branch unit 14b are gathered together in one pipe. And on the opposite side of the heat exchanger 11, a header 11d is connected that collects a plurality of connection ports 11c serving as an outlet during cooling operation of the heat transfer tube path and an inlet during heating operation.

About the heat exchanger unit comprised as mentioned above, the operation | movement and an effect | action are demonstrated. First, when the heat exchanger 11 is used as an evaporator, the condensed refrigerant is decompressed and expanded by an expansion device (not shown), and a plurality of transmissions of the indoor heat exchanger 11 are transmitted via the branch unit 14a and the balance pipe 15a. It flows into the heat pipe path 11a. When the inflowing refrigerant passes through the heat transfer tubes, heat energy is exchanged with the air in the vicinity of the fins through the fins to exchange heat, and moisture in the air condenses on the fin surfaces. The condensed water attached to the fins gradually flows down, but tends to accumulate between the fins at the bottom of the heat exchanger 11. Furthermore, depending on the installation position of the drain outlet, the water level of the drain pan rises, and the lower part of the heat exchanger 11 is immersed in the drain water, so that the amount of heat exchange between the fins and air is smaller than in other locations.

  For this reason, a balance pipe 15a having a larger flow resistance is connected to the bottom heat transfer pipe path e where the heat exchange amount is smaller than in other places, the flow rate is adjusted, and the refrigerant is transferred to the heat transfer pipe path 11a having a larger heat exchange. Is flowing more.

  On the other hand, when the heat exchanger 11 is used as a condenser, condensed water is not generated on the surface of the heat exchanger 11, so that there is no shortage of heat exchange at the bottom. Therefore, it is not necessary to adjust the flow rate of the refrigerant. Then, since a refrigerant | coolant flows equally into the heat exchanger tube path | route 11a through the balance pipe 15b, heat exchange can be performed efficiently in the heat exchanger 11 whole.

  As described above, in the present embodiment, the heat exchange for each heat transfer tube path of the heat exchanger, which varies depending on the presence or absence of condensed water at the bottom of the heat exchanger caused by the operating state of the evaporator or condenser, that is, cooling or heating. Since it is possible to cope with an unbalanced amount, it is possible not only to prevent the capacity of the heat exchanger unit from being lowered, but also to reduce power consumption.

(Embodiment 2)
FIG. 2 is a heat exchanger unit diagram according to Embodiment 2 of the present invention. In FIG. 2, all the heat transfer pipe paths 11a are provided with balance pipes 15c, and only a specific heat transfer pipe path (bottom heat transfer pipe path e) is provided with a check valve 16c for stopping the refrigerant flow during the cooling operation. . The heat transfer tube path e at the bottom is provided with a balance tube 15d for adjusting the flow rate of the refrigerant during the cooling operation.

  About the heat exchanger unit comprised as mentioned above, the operation | movement and an effect | action are demonstrated. When the heat exchanger 11 is operated as an evaporator, the refrigerant is supplied to the balance pipe 15c not equipped with the switchgear and the check pipe 16 in the bottom heat transfer pipe path e to the balance pipe 15d in which the refrigerant flow rate is adjusted. Flows. Thereby, since it can respond | correspond for every heat exchanger tube path | route with respect to the heat exchanger 11 in which the heat exchange amount became unbalanced with condensed water, it can prevent that the capability of a heat exchanger unit falls.

  Conversely, when the heat exchanger 11 is used as a condenser, the refrigerant flows through both the balance pipe 15d provided with the check valve 16c and the balance pipe 15d for adjusting the evaporator flow rate. Since the flow resistance is large, there is almost no effect and there is no problem. Of course, if necessary, the balance pipe 15d may be provided with a check valve in the opposite direction to the balance pipe 15c.

  In the present embodiment, the provision of the two balance pipes corresponding to the cooling and heating in one heat transfer pipe path is a single heat transfer pipe path at the bottom. However, the present invention is not limited to this. Two balance pipes adjusted for each path may be provided, and a check valve may be provided according to a necessary circulation amount.

  As described above, in the present embodiment, since the apparatus capable of dealing with the amount of heat exchanger that changes depending on the presence or absence of condensed water at the bottom of the heat exchanger caused by the operating state can be made compact, only the performance improvement of the heat exchanger unit is achieved. In addition, the design flexibility can be improved and the cost can be reduced.

  Regardless of the operation state of the heat exchanger unit of the present invention, the heat exchanger capacity can be maximized, so that it can be applied to various refrigeration cycles.

The schematic diagram of the heat exchanger unit in Embodiment 1 of this invention The schematic diagram of the heat exchanger unit in Embodiment 2 of this invention Schematic diagram of a conventional heat exchanger unit

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Heat exchanger 11a Heat transfer pipe path 11b, 11c Connection port 11d Header 11e Heat transfer pipe path 12 Blower 13 Drain pan 14, 14a, 14b Branch unit 15, 15a, 15b, 15c, 15d Balance pipe 16a, 16b Check valve

Claims (2)

In a refrigeration cycle unit that can be switched between a cooling operation and a heating operation, a heat exchanger, a branch unit that distributes refrigerant to each heat transfer tube path of the heat exchanger, and the branch unit and the heat exchanger are connected. A balance pipe, a blower for heat exchange, and a drain pan that receives condensed water generated in the heat exchanger. The balance pipe is provided as two balance pipes for cooling and heating in one heat transfer pipe path. A branch unit having an opening / closing device for each is provided, and the amount of refrigerant flowing into each heat transfer tube path is adjusted by selectively using the two balance tubes by the opening / closing device according to the operating state of air conditioning. Exchange unit. In a refrigeration cycle unit that can be switched between a cooling operation and a heating operation, a heat exchanger, a branch unit that distributes refrigerant to each heat transfer tube path of the heat exchanger, and the branch unit and the heat exchanger are connected. A balance pipe, a blower for heat exchange, and a drain pan that receives condensed water generated in the heat exchanger. The balance pipe is provided in one heat transfer pipe path for cooling and heating as needed. Heat is characterized by adjusting the amount of refrigerant flowing into each heat transfer tube path by providing an open / close device in the balance tube as needed, and using the balance tube appropriately according to the operating state of the air conditioning. Exchange unit.