JP2017180884A - Evaporator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an evaporator which causes evaporation of a refrigerant resulting from heat exchange with air to occur in not only a lower side tube but also an upper side tube even when a longitudinal direction of a tank is set along a vertical direction.SOLUTION: A receiving part 110 for receiving a refrigerant supplied from the outside is formed at a first tank 100 of an evaporator 10. The receiving part 110 is provided with a direction change part 300 which changes a flow direction of the supplied refrigerant to a direction toward the tube 11 in the first tank 100.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an evaporator that evaporates a refrigerant by heat exchange with air.

  For example, a refrigeration cycle used in a vehicle air conditioner or the like includes an evaporator that evaporates the refrigerant by exchanging heat with air. During the operation of the refrigeration cycle, low-temperature and low-pressure refrigerant that has passed through the upstream throttle valve is supplied to the evaporator in a liquid phase state.

  The evaporator is provided with a tank for receiving the refrigerant from the outside. The refrigerant supplied to the tank is distributed to a plurality of tubes connected to the tank, and then heated by external air while flowing through the tubes. In addition, the structure provided with a tank and a tube as mentioned above is employ | adopted not only in an evaporator but in a condenser, and has become a general structure in a heat exchanger (for example, the following patent document 1 is described). reference).

  In order to sufficiently exhibit the endothermic performance of the evaporator, it is desirable to reduce the pressure loss when the refrigerant flows through the plurality of tubes as much as possible. In addition, it is desirable that the evaporation of the refrigerant accompanying the heat exchange with the air, that is, the change from the liquid phase to the gas phase is caused to occur as uniformly as possible in each tube.

JP 2011-89729 A

  In order to reduce the pressure loss, the flow path cross-sectional area of the path through which the refrigerant flows inside the evaporator may be increased. Or what is necessary is just to shorten the path | route through which a refrigerant | coolant flows inside an evaporator. In order to realize this, it is desirable that the refrigerant supplied from the outside and received in the tank is distributed to flow as many tubes as possible.

  However, it is not easy to evenly distribute the liquid-phase refrigerant to many tubes. In particular, in an evaporator having a configuration in which the longitudinal direction of the tank is along the vertical direction and a plurality of tubes are stacked in the vertical direction, the liquid phase refrigerant from the tank is placed in the tubes arranged on the upper side. It is difficult to flow in, and only the gas phase refrigerant may flow. In this case, the evaporation of the refrigerant does not occur in the upper tube, but locally occurs only in the lower portion. As a result, the endothermic performance of the evaporator is not sufficiently exhibited.

  The present invention has been made in view of such problems, and the purpose of the present invention is to evaporate the refrigerant accompanying heat exchange with air even when the longitudinal direction of the tank is arranged along the vertical direction. It is an object of the present invention to provide an evaporator that can generate not only a lower tube but also an upper tube.

  In order to solve the above problems, an evaporator according to the present invention is a container for temporarily storing a refrigerant supplied from the outside, and is a first tank (100) whose longitudinal direction is along the vertical direction. ), One end of which is connected to the first tank, and a plurality of tubes (11) in which a flow path through which the refrigerant flows is formed, and a container to which the other ends of the respective tubes are connected, the length of which is A second tank (200) arranged so that the direction is along the vertical direction. The first tank is formed with a receiving portion (110) for receiving a refrigerant supplied from the outside. The receiving portion is provided with a direction changing portion (300, 300A, 300B) that changes the flow direction of the supplied refrigerant so as to be in the direction toward the tube inside the first tank.

  In the evaporator having such a configuration, the refrigerant supplied to the receiving portion of the first tank changes the flow direction in the first tank so as to be directed toward the tube. Thus, the liquid-phase refrigerant can be surely flowed even in the upper tube where the liquid-phase refrigerant is difficult to flow. As a result, it is possible to cause evaporation of the refrigerant accompanying heat exchange with air not only in the lower tube but also in the upper tube.

  According to the present invention, even in the case where the longitudinal direction of the tank is arranged along the vertical direction, the evaporation of the refrigerant accompanying the heat exchange with the air is performed not only in the lower tube but also in the upper tube. An evaporator can also be provided.

It is a figure which shows the whole structure of the evaporator which concerns on 1st Embodiment of this invention. It is a figure which shows the structure in the A section of FIG. It is a figure which shows the structure of a direction change part. It is a figure which shows typically the flow of the refrigerant | coolant in the inside of a 1st tank. It is a figure which shows typically distribution of the liquid phase refrigerant | coolant in a heat exchange core part. It is a figure which shows the structure of the direction change part provided in the evaporator which concerns on 2nd Embodiment of this invention. It is a figure which shows the structure of the direction change part provided in the evaporator which concerns on 3rd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In order to facilitate the understanding of the description, the same constituent elements in the drawings will be denoted by the same reference numerals as much as possible, and redundant description will be omitted.

  The configuration of the evaporator 10 according to the embodiment of the present invention will be described with reference to FIG. The evaporator 10 is used as a part of a refrigeration cycle (not shown) of a vehicle air conditioner. Like the conventional evaporator, the evaporator 10 is configured as a device for evaporating the refrigerant inside by heat exchange with the air flowing outside.

  Note that the evaporator 10 may be a heat exchanger used as part of a heat pump system. That is, the evaporator 10 does not need to be a heat exchanger that always functions as an evaporator, and may be a heat exchanger that temporarily functions as a condenser depending on the operation mode of the heat pump system.

  The evaporator 10 includes a first tank 100, a second tank 200, a tube 11, and fins 12.

  The first tank 100 is a container for temporarily storing a refrigerant supplied from the outside. The first tank 100 is formed as a substantially cylindrical elongated container, and is arranged in a state where the longitudinal direction thereof is along the vertical direction.

  A receiving portion 110 is formed in a portion of the first tank 100 above the center position in the vertical direction. The receiving unit 110 is a part that receives a refrigerant supplied from the outside and allows the refrigerant to flow into the first tank 100. The receiving part 110 is formed as a connector for connecting a pipe through which a refrigerant flows in the refrigeration cycle. The receiving part 110 is formed with a substantially circular opening 111 that serves as an inlet for the supplied refrigerant.

  Similar to the first tank 100, the second tank 200 is provided as a container for temporarily storing the refrigerant. The second tank 200 is formed as a substantially cylindrical elongated container, and is arranged in a state where the longitudinal direction thereof is along the vertical direction. The second tank 200 is arranged such that its longitudinal direction is parallel to the longitudinal direction of the first tank 100.

  A discharge portion 210 is formed in a portion of the second tank 200 below the center position in the vertical direction. The discharge part 210 is a part for discharging the refrigerant once stored in the second tank 200 through the tube 11 to the outside. Similarly to the receiving part 110 of the first tank 100, the discharge part 210 is formed as a connector for connecting a pipe through which a refrigerant flows in the refrigeration cycle. The discharge portion 210 is formed with a substantially circular opening 211 that serves as an outlet for the discharged refrigerant.

  The tube 11 is a metal pipe formed in a cylindrical shape, and a plurality of tubes 11 are provided in the evaporator 10. The internal space of the tube 11 is a flow path through which the refrigerant flows from the first tank 100 toward the second tank 200. The shape of the tube 11 in a cross section perpendicular to the refrigerant flow direction is a flat shape, and the longitudinal direction of the flat shape is along the air flow direction (the direction perpendicular to the paper surface in FIG. 1).

  Each tube 11 has one end connected to the first tank 100 and the other end connected to the second tank 200. As a result, the internal space of the first tank 100 communicates with the internal space of the second tank 200 via the respective tubes 11.

  Each tube 11 is held in a state in which the longitudinal direction thereof is perpendicular to the longitudinal direction of the first tank 100 and the like, and is stacked along the longitudinal direction (that is, the vertical direction) of the first tank 100 and the like. Has been.

  The fins 12 are metal plates bent in a wave shape, and are inserted between adjacent tubes 11. Each top part of the fin 12 which is wavy is brazed to the side surface (upper and lower surfaces) of the tube 11. During the operation of the refrigeration cycle, the heat of the passing air is directly transmitted to the tube 11 and is also transmitted to the tube 11 through the fins 12. In other words, the contact area with the air is increased by the fins 12, thereby efficiently exchanging heat between the air and the refrigerant.

  A portion where all the stacked tubes 11 and fins 12 are arranged is also referred to as a “heat exchange core portion” below. The heat exchange core part is a part where heat exchange is performed between the external air and the internal refrigerant. Side plates 13 and 14, which are flat metal plates, are provided at positions on the upper and lower sides of the heat exchange core portion. The side plates 13 and 14 are for reinforcing the heat exchange core part and maintaining its shape by sandwiching the heat exchange core part from above and below.

  The refrigerant flow when the refrigeration cycle is operating will be described. The refrigerant passes through an expansion valve (not shown) on the upstream side of the evaporator 10 and is supplied to the evaporator 10 with its temperature and pressure lowered. At this time, the refrigerant is almost entirely in a liquid phase. As already described, the refrigerant flows into the first tank 100 from the receiving unit 110 and is temporarily stored in the first tank 100.

  Thereafter, the refrigerant flows into the respective tubes 11 and flows toward the second tank 200 through the tubes 11. A compressor (not shown) for circulating the refrigerant is arranged at a position downstream of the evaporator 10 in the refrigeration cycle. Inside the first tank 100, the refrigerant is distributed to the tubes 11 by the suction force of the compressor.

  When the refrigerant passes through the tube 11, it is heated by external air that passes through the heat exchange core part. That is, heat is absorbed from the air. Thereby, the refrigerant | coolant which passes along the tube 11 raises the temperature, and the one part or all changes from a liquid phase to a gaseous phase. Further, the air passing through the heat exchange core part is deprived of its heat and cooled.

  The refrigerant that has passed through each tube 11 flows into the second tank 200 and is temporarily stored in the second tank 200. Thereafter, the refrigerant is discharged to the outside from the discharge unit 210 formed in the second tank 200 and flows toward the compressor of the refrigeration cycle.

  In the present embodiment, the refrigerant does not reciprocate between the first tank 100 and the second tank 200 but all the refrigerant flows from the first tank 100 toward the second tank 200 only once. It has become. As a result, the flow path of the refrigerant in the evaporator 10 is relatively short, and the pressure loss in the refrigerant flow is relatively small.

  The number of tubes 11 through which the refrigerant is distributed from the first tank 100 at a time is larger than when the refrigerant flows back and forth. In such a configuration, it is not easy to allow the liquid-phase refrigerant to uniformly flow into all the tubes 11. Most of the liquid-phase refrigerant supplied from the receiving unit 110 to the inside of the first tank 100 falls downward due to the influence of gravity. As a result, it is difficult for the liquid-phase refrigerant to flow into the tube 11 disposed in the upper portion of the heat exchange core, and only the gas-phase refrigerant tends to flow.

  In this case, since the refrigerant does not evaporate in the upper tube 11, the heat absorption from the air is not efficiently performed. In other words, since the evaporation of the refrigerant occurs locally only in the lower part of the heat exchange core part, the endothermic performance of the evaporator 10 is not sufficiently exhibited.

  Therefore, in the evaporator 10 according to the present embodiment, the refrigerant is prevented from flowing into the upper tube 11 by devising the configuration of the receiving unit 110.

  FIG. 2 is a perspective view of a portion of the evaporator 10 indicated by a dotted line A in FIG. As shown in FIG. 2, a direction changing unit 300 is provided inside the receiving unit 110. The direction changing unit 300 is a member that is formed in advance as a separate component from the first tank 100 and is then inserted and attached to the receiving unit 110. The overall shape of the direction changing unit 300 is shown in FIG.

  The direction changing unit 300 is inserted into the first tank 100 from the opening 111 of the receiving unit 110 and is fixed to the first tank 100. The direction changing unit 300 is a flat member as a whole, and a space is formed in the inside thereof. An opening 302 is formed in a portion of the direction changing unit 300 closest to the opening 111. The opening 302 is a portion serving as an inlet when the refrigerant supplied to the receiving unit 110 flows into the direction changing unit 300.

  A pair of plate-like portions 303 and 304 that protrude toward the opening 111 are formed in the direction change portion 300 at the edge of the opening 302. The plate-like parts 303 and 304 are parts formed to fix the direction changing part 300 to the first tank 100. Further, the plate-like portions 303 and 304 also function as portions for guiding all of the refrigerant supplied to the receiving portion 110 from the opening 302 to the inside of the direction changing portion 300.

  An injection hole 310 is formed on the side of the direction changing unit 300 facing the tube 11 inside the first tank 100. By the injection hole 310, the internal space of the first tank 100 and the internal space of the direction changing unit 300 are communicated. For this reason, when a refrigerant is supplied to the receiving unit 110, the refrigerant changes its flow direction toward the tube 11, and is directed from the injection hole 310 toward the tube 11 inside the first tank 100. Be injected. As described above, the direction changing unit 300 functions as a unit that changes the flow direction of the supplied refrigerant so as to be a direction toward the tube 11 inside the first tank 100.

  By providing such a direction changing unit 300, the liquid phase refrigerant flows into the tube 11 disposed in the upper portion, particularly the tube 11 provided at the same height as the direction changing unit 300. It becomes easy to do. This will be described with reference to FIGS.

  FIG. 4A shows a cross section when the first tank 100 and the receiving unit 110 are cut along a horizontal plane when the direction changing unit 300 is not provided. In FIG. 4A, the flow of the refrigerant in the first tank 100 is indicated by an arrow.

  4A, the refrigerant supplied from the opening 111 is supplied to the inside of the first tank 100 through the passage 112 formed inside the receiving unit 110. The passage 112 is a space in which the direction changing unit 300 is inserted.

  As shown by an arrow in FIG. 4A, the supplied refrigerant flows along the inner wall surface while sticking to the inner wall surface of the first tank 100. In order for the liquid-phase refrigerant to flow into the tube 11 in the vicinity of the receiving portion 110, it is necessary to get over the wall surface of the tube 11 protruding inside the first tank 100. Actually, since such a flow hardly occurs, most of the liquid-phase refrigerant falls down without flowing into the tube 11.

  In FIG. 5A, the hatched lines indicate that the liquid phase refrigerant is present during the operation of the refrigeration cycle in the heat exchange core unit when the direction changing unit 300 is not provided as described above. It is an area. In FIG. 5A, the receiving unit 110 and the discharging unit 210 are not shown. Instead, the flow of the refrigerant supplied from the receiving unit 110 is indicated by an arrow AR1, and the flow of the refrigerant discharged from the discharge unit 210 is indicated by an arrow AR2. The same applies to FIG. 5B described later.

  In the case of FIG. 4A, most of the refrigerant supplied from the receiving unit 110 to the inside of the first tank 100 falls downward as described above. Therefore, as shown in FIG. 5A, most of the liquid-phase refrigerant flows toward the second tank 200 only through the tube 11 connected to the lower side of the first tank 100. That is, the liquid-phase refrigerant flows only in the lower portion (the hatched portion marked with the symbol D1) of the heat exchange core portion, and the gas-phase refrigerant flows in the other portions. In such a state, the refrigerant is not evaporated in a region other than the shaded portion, and almost no heat is absorbed from the air.

  FIG. 4B shows a cross section when the first tank 100 according to the present embodiment, that is, the first tank 100 provided with the direction changing unit 300 and the receiving unit 110 are cut along a horizontal plane. Yes. In such a configuration, all of the refrigerant supplied to the receiving unit 110 flows into the direction changing unit 300 from the opening 302 and is directed toward the tube 11 from the injection hole 310 (right side in FIG. 4B). To be injected).

  In FIG. 5B, the hatched area is a region where the liquid-phase refrigerant is present during the operation of the refrigeration cycle in the heat exchange core portion of the evaporator 10 according to the present embodiment. In the present embodiment, the liquid-phase refrigerant is ejected from the direction changing unit 300 toward the tube 11 as described above. For this reason, part of the injected liquid-phase refrigerant flows directly into the tube 11 at the same height as the receiving unit 110 and flows through the tube 11 toward the second tank 200 as it is. As a result, the liquid-phase refrigerant flows even in the heat exchange core portion having the same height as the receiving portion 110 (the hatched portion marked with the symbol D2). The refrigerant is evaporated not only in the area D1 but also in the area D2, and heat is absorbed from the air. According to the experiments conducted by the present inventors, the endothermic performance of the evaporator 10 can be increased by 30% compared to the prior art by providing the direction changing unit 300.

  A second embodiment of the present invention will be described. The evaporator (the whole is not shown) according to the second embodiment is different from the first embodiment only in the shape of the direction changing unit 300A, and is the same as the first embodiment in other points. Below, only a different part from 1st Embodiment is demonstrated, and description is abbreviate | omitted suitably about the part which is common in 1st Embodiment.

  The shape of the direction changing unit 300A will be described with reference to FIG. A plurality of injection holes 310A are formed in the direction changing portion 300A. Each injection hole 310 </ b> A is formed as a circular opening, and is formed so as to be arranged in two upper and lower rows on the side surface of the direction changing portion 300 </ b> A facing the tube 11.

  In such a configuration, since the opening area of each injection hole 310A is small, the flow rate of the injected refrigerant can be increased, and the liquid-phase refrigerant can be more reliably flowed into the tube 11 having the same height. Can do. In addition, since the plurality of injection holes 310A are formed so as to be arranged in two upper and lower rows, liquid phase refrigerant can be injected over a wide range. Further, the injection holes 310A may be formed so as to be arranged in three or more rows in the upper and lower directions. Even in such an embodiment, the same effects as described above can be obtained.

  A third embodiment of the present invention will be described. The evaporator (the whole is not shown) according to the third embodiment is different from the first embodiment only in the shape of the direction changing unit 300B, and is the same as the first embodiment in other points. Below, only a different part from 1st Embodiment is demonstrated, and description is abbreviate | omitted suitably about the part which is common in 1st Embodiment.

  The shape of the direction changing unit 300B will be described with reference to FIG. A plurality of injection holes 310B are formed in the direction changing portion 300B. Each of the injection holes 310B is formed as a slit-like opening extending up and down, and is formed so as to be arranged in a line on the side surface of the direction changing portion 300B facing the tube 11. Even in such a configuration, the same effects as those of the second embodiment are obtained.

  In the above embodiment, the receiving part 110 is the upper side part of the 1st tank 100, ie, the structure formed in the position which becomes above a center in the up-down direction. In such a configuration, the effect of providing the direction changing unit 300 or the like is particularly easily exhibited. However, even in an evaporator having a configuration in which the receiving unit 110 is formed in the lower part of the first tank 100, the direction changing unit 300 or the like can be provided in the receiving unit 110. The same effect can be exhibited.

  In the above embodiment, the direction changing unit 300 or the like is formed in advance as a separate component from the first tank 100 and then attached to the receiving unit 110 of the first tank 100. Instead of such a configuration, the direction changing unit 300 may be integrally formed with the first tank 100 (and the receiving unit 110).

  The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. In other words, those specific examples that have been appropriately modified by those skilled in the art are also included in the scope of the present invention as long as they have the characteristics of the present invention. For example, the elements included in each of the specific examples described above and their arrangement, materials, conditions, shapes, sizes, and the like are not limited to those illustrated, and can be changed as appropriate. Moreover, each element with which each embodiment mentioned above is provided can be combined as long as technically possible, and the combination of these is also included in the scope of the present invention as long as it includes the features of the present invention.

10: evaporator 11: tube 100: first tank 110: receiving part 200: second tank 300, 300A, 300B: direction changing part 310, 310A, 310B: injection hole

Claims (6)

An evaporator (10) for evaporating a refrigerant by heat exchange with air,
A first tank (100), which is a container for temporarily storing a refrigerant supplied from the outside and is arranged such that its longitudinal direction is along the vertical direction;
A plurality of tubes (11) each having one end connected to the first tank and having a flow path through which a refrigerant flows;
A container to which the other end of each tube is connected, and a second tank (200) arranged so that its longitudinal direction is along the vertical direction, and
The first tank is formed with a receiving part (110) for receiving a refrigerant supplied from the outside into the inside,
In the receiving part,
The evaporator provided with the direction change part (300, 300A, 300B) which changes the flow direction of the supplied refrigerant | coolant so that it may become the direction which goes to the said tube inside the said 1st tank.   The injection hole (310, 310A, 310B) for injecting a refrigerant | coolant toward the said tube side is formed in the part arrange | positioned inside the said 1st tank among the said direction change parts. The evaporator as described in.   The evaporator according to claim 2, wherein a plurality of the injection holes are formed.   2. The evaporator according to claim 1, wherein the direction changing unit is formed as a separate component from the first tank and then attached to the receiving unit.   The evaporator according to claim 1, wherein the direction changing portion is integrally formed with the receiving portion.   The evaporator according to claim 1, wherein the receiving portion is formed in an upper portion of the first tank.

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