JP2005291659A - Evaporator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an evaporator capable of reducing the unevenness in temperature distribution by reducing an area where a blowout temperature is increased because of the shortage of liquid-phase refrigerant, in the evaporator where the circulating directions of the refrigerant are opposite to each other between a windward-side path and a leeward-side path. <P>SOLUTION: In a structure where the refrigerant circulating directions are opposite to each other between a windward-side heat exchanging part 20 and a leeward-side heat exchanging part 10, restriction parts 34a, 38b having passage sectional areas S1, S2 smaller than passage sectional areas S0 of upper tank parts 11a, 21a are mounted at inlets of the upper tank parts 11a, 21a of all of downward flow paths 10a, 20a. Whereby a circulating speed of the refrigerant is increased by restriction action of the inlets 34a, 38b at the upper tank parts 11a, 21a of the downward flow paths 10a, 20a, and the refrigerant swiftly flows toward a downstream side in the tank longitudinal direction. Thus the deviation of the liquid-phase refrigerant at an upstream side in the tank longitudinal direction of the upper tank parts 11a, 21a of the downward flow paths 10a, 20a, can be prevented, the distribution of the refrigerant in the downward paths 10a, 20a is improved, and further the uniform temperature distribution can be achieved. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an evaporator in which heat exchange units are arranged side by side on the windward and leeward sides.

  For example, as disclosed in Patent Documents 1 to 5, there is an evaporator in which two heat exchange units are conventionally arranged on the windward and leeward sides. FIG. 19 shows an example of an evaporator in which two heat exchange parts of this type are arranged in parallel on the windward side and the leeward side, and is a structural example similar to the evaporator of Patent Document 5. The evaporator 100 shown in FIG. 19 includes an upper tank 111, a lower tank 112, and a leeward heat exchange unit 110 having a plurality of heat exchange passages connected in communication between the tanks 111, 112, and an upper tank 121 and a lower tank. A tank 122 and an upwind heat exchanging unit 120 having a plurality of heat exchange passages connected in communication between the tanks 121 and 122 are arranged so as to overlap in the air blowing direction.

  In the leeward heat exchanger 110, an evaporator inlet 107 is provided at the right end of the upper tank 111, and the upper tank 111 is partitioned into an upper first tank portion 111a and an upper second tank portion 111b by a partitioning portion 114. Thereby, the heat exchange passage group stacked in a plurality of stages is partitioned into the first path 110a and the second path 110b in order from the right to the left. The refrigerant introduced into the leeward heat exchange unit 110 from the evaporator inlet 107 flows in the order of the upper first tank unit 111a → the first path 110a → the lower tank 112 → the second path 110b → the upper second tank unit 111b. And a refrigerant | coolant is introduce | transduced into the upper 1st tank part 121a as an uppermost stream part of the windward heat exchange part 120 through the communicating path 109 from the upper 2nd tank part 111b as the most downstream part of the leeward side heat exchange part 110. FIG. .

On the other hand, in the upwind heat exchanging unit 120, the upper tank 121 is divided into an upper first tank unit 121a and an upper second tank unit 121b by a partition unit 124. Thereby, the heat exchange passage groups stacked in a plurality of stages are partitioned into the first path 120a and the second path 120b in order from the left to the right. The refrigerant introduced into the windward heat exchange unit 120 from the communication path 109 flows in the order of the upper first tank unit 121a → the first path 120a → the lower tank 122 → the second path 120b → the upper second tank unit 121b. And this refrigerant | coolant is derived | led-out outside the evaporator 100 from the evaporator exit 108 provided in the right end of the upper 2nd tank 121b as the most downstream part of the windward heat exchange part 120. FIG. Note that the circled numbers in FIG. 19 are numbers added to the paths along the order in which the refrigerant flows. In the evaporator 100, the refrigerant flow directions of the paths superimposed on the windward side and the leeward side are opposite to each other including the flow of the upstream and downstream tank portions.
JP-A-6-74679 Japanese Patent Laid-Open No. 10-238896 JP 2000-105091 A JP 2001-74388 A Japanese Utility Model Publication No. 7-12778

  Thus, in the evaporator 100 in which the two heat exchange units 110 and 120 are stacked in the direction of the wind flow, the heat exchange between the two heat exchange units 110 and 120 can be complemented with each other. As compared with the case, the unevenness of the temperature distribution can be reduced (see FIG. 20b). However, unevenness still occurs (see FIG. 20b).

  The present invention has been made in view of the above points, and is an evaporator that is set so that the flow direction of the refrigerant is reversed between the opposite windward path and the leeward path, and the liquid phase refrigerant is insufficient. Another object of the present invention is to provide an evaporator in which the region where the blowing temperature becomes high is reduced to reduce unevenness in temperature distribution.

  When the inventor specifically researched which region is deficient in liquid phase refrigerant, it was found that the liquid phase refrigerant is deficient in the following regions. FIG. 20a shows the distribution of the liquid-phase refrigerant in each of the heat exchange units 110 and 120, and FIG. 20b shows the distribution of the liquid-phase refrigerant as a whole evaporator in which these are superposed.

  As shown in FIG. 20a, in the downflow paths 110a and 120a where the circulating refrigerant flows downward, the liquid refrigerant flowing from the upper tank descends by its own weight before reaching the downstream side in the longitudinal direction of the upper tank portions 111a and 121a. Therefore, the liquid phase refrigerant is insufficient on the downstream side in the tank longitudinal direction. For example, taking the downward flow path 110a as an example in FIG. 20a, the liquid phase refrigerant is insufficient on the downstream side in the longitudinal direction of the upper tank portion 111a (left side in FIG. 20a).

  In the upward flow paths 110b and 120b in which the circulating refrigerant flows upward, the upward flow path 110b and the liquid phase refrigerant flowing from the lower tanks 112 and 122 are pushed to the downstream side in the longitudinal direction of the tank and reach a predetermined pressure. Since 120b is raised, the liquid-phase refrigerant is biased toward the downstream side in the tank longitudinal direction and is insufficient on the upstream side in the tank longitudinal direction. For example, taking the upward flow path 110b as an example in FIG. 20a, the refrigerant runs short on the downstream side in the longitudinal direction of the lower tank 112 (right side in FIG. 20a).

  For this reason, the distribution of the liquid-phase refrigerant in the entire evaporator 100 in which the windward heat exchange unit 120 and the leeward heat exchange unit 110 are overlapped is as shown in FIG. 20b, and the two heat exchange units 110 and 120 are stacked. Even when combined, a non-low temperature region was generated, and it was found that the temperature distribution was uneven.

  Therefore, the present inventor pays attention to the downward flow path, and the liquid phase refrigerant descends by its own weight from the upstream side in the longitudinal direction of the tank in the upper tank of the downward flow path, so that the upper tanks of the downward flow paths 10a and 20a A device was devised to prevent the liquid-phase refrigerant from being biased upstream in the tank longitudinal direction.

According to the first aspect of the present invention, there is provided a tank in which a plurality of heat exchange passages extending in the vertical direction and flowing the refrigerant therein are stacked in a plurality of stages, and the refrigerant from the heat exchange passages is merged and distributed at both upper and lower ends of the plurality of multistage heat exchange paths. In the evaporator provided with the heat exchange part provided, and arranged in two layers with the heat exchange part passing in the direction of air flow,
An evaporator in which the flow direction of the refrigerant is reversed in the opposite heat exchange part,
A throttle part having a passage cross-sectional area set smaller than the passage cross-sectional area of the upper tank is provided at the inlet of the upper tank of all the downflow paths.

  The invention of claim 2 is the evaporator according to claim 1, wherein the number of heat exchange passages in the upward flow path in which the refrigerant is an upward flow is set smaller than the downward flow path in which the refrigerant is a downward flow. It is a feature.

  Invention of Claim 3 is an evaporator of Claim 1, Comprising: It is a structure which distribute | circulates the refrigerant | coolant which distribute | circulated to any one heat exchange part as it is to the other heat exchange part, and heat of a refrigerant | coolant upstream. A communication path that connects the most downstream part of the exchange part and the most upstream part of the heat exchange path downstream of the refrigerant is integrated with a side plate that is attached to the outermost side in the stacking direction of the heat exchange path and reinforces the strength of the evaporator. It is formed.

  Invention of Claim 4 is an evaporator of Claim 1, Comprising: It is a structure which distribute | circulates the refrigerant | coolant distribute | circulated to any one heat exchange part as it is to the other heat exchange part, and heat | fever of the refrigerant | coolant upstream side The exchanger is arranged on the leeward side, and the heat exchanger on the downstream side of the refrigerant is arranged on the leeward side.

  According to the first aspect of the present invention, since the throttle portion is provided at the inlet of the upper tank of the downflow path, the refrigerant circulates vigorously toward the downstream side in the tank longitudinal direction of the upper tank. Thus, by actively pushing the refrigerant in the tank longitudinal direction downstream side of the upper tank of the downflow path, it is possible to prevent the liquid phase refrigerant from being biased upstream in the tank longitudinal direction of the upper tank of the downflow path. . As a result, the refrigerant distribution in all the downflow paths of the evaporator is improved, and an evaporator with less uneven temperature distribution is obtained.

  According to the invention of claim 2, in addition to the effect of the invention of claim 1, the number of heat exchange passages in the upward flow path in which the refrigerant becomes an upward flow is set smaller than the downward flow path in which the refrigerant becomes a downward flow, It is possible to increase the amount of liquid-phase refrigerant on the upstream side in the longitudinal direction of the tank, where the liquid-phase refrigerant tends to be insufficient in the upward flow path. Thereby, a more uniform temperature distribution can be achieved.

  According to the invention of claim 3, in addition to the effect of the invention of claim 1, the communication path that communicates the most downstream part of the heat exchange part on the refrigerant upstream side and the most upstream part of the heat exchange path on the refrigerant downstream side, Since it is integrally formed on the side plate that is attached to the outermost side of the heat exchange passage in the stacking direction and reinforces the strength of the evaporator, it is not necessary to prepare a separate member for the communication passage. Therefore, the manufacturing cost can be reduced.

  According to the invention of claim 4, in addition to the effect of the invention of claim 1, the inlet side heat exchange part is arranged on the leeward side and the outlet side heat exchange part is arranged on the leeward side. The air ventilated by the heat exchanger is cooled, and then the cooled air can be further cooled by the inlet side heat exchange section having a temperature lower than that of the outlet side heat exchange section. That is, it is possible to cool the air that is ventilated stepwise in the heat exchange section on the leeward side and the leeward side. As a result, the windward and leeward heat exchange sections can be efficiently used without waste, and the heat exchange efficiency can be further improved.

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

  1st Embodiment: The evaporator of 1st Embodiment of this invention is demonstrated based on FIGS. The evaporator 1 heat-exchanges the refrigerant | coolant which flows through the inside, and the air which passes the outside, evaporates and evaporates a refrigerant | coolant, and cools air. The evaporator 1 of this embodiment is used for an automotive air conditioner, for example.

"Overall structure of the evaporator"
First, the structure of the evaporator will be schematically described with reference to FIGS. 11 is a vertical sectional view schematically showing the structure of the leeward heat exchanger of the evaporator according to the first embodiment, FIG. 12 is a vertical sectional view schematically showing the structure of the leeward heat exchanger of the evaporator, FIG. 13 is a perspective view schematically showing the flow of the refrigerant in the evaporator, and FIG. 14 is a schematic view showing the distribution of the liquid-phase refrigerant in the evaporator.

  The evaporator 1 includes an upwind heat exchange unit 20 and a downwind heat exchange unit 10 that overlap in the air blowing direction in the front-rear direction.

  As shown in FIGS. 11 and 13, the leeward heat exchange unit 10 includes an upper tank 11 and a lower tank 12, and a plurality of heat exchange passages 31 connected in communication between the tanks 11 and 12. On the other hand, as shown in FIGS. 12 and 13, the windward side heat exchange unit 20 includes an upper tank 21, a lower tank 22, and a plurality of heat exchange passages 31 connected in communication between the tanks 21 and 22.

  In the leeward side heat exchange unit 10, the upper tank 11 is partitioned into an upper first tank unit 11 a and an upper second tank unit 11 b by a partition unit 14. An evaporator inlet 7 is provided at the right end of the upper tank 11, and a plurality of heat exchange passage groups stacked in multiple stages are sequentially divided into a first path 10a and a second path 10b from the right to the left. As a result, the refrigerant introduced from the evaporator inlet 7 into the leeward heat exchange unit 10 is in the order of the upper first tank unit 11a → the first pass 10a → the lower tank 12 → the second pass 10b → the upper second tank unit 11b. It is supposed to flow in. Then, the refrigerant is introduced from the most downstream portion (upper second tank portion 11b) of the leeward heat exchange unit 10 into the most upstream portion (upper first tank portion 21a) of the upwind heat exchange unit 20 through the communication path 9. Is done.

  On the other hand, in the windward heat exchange unit 20, as shown in FIGS. 12 and 13, the upper tank 21 is divided into an upper first tank unit 21a and an upper second tank unit 21b by a partition unit 24. The partition portion 24 is provided at a position facing the partition portion 14. The evaporator outlet 8 is provided at the right end of the upper tank 21, and a plurality of heat exchange passage groups stacked in multiple stages are sequentially divided into a first path 20a and a second path 20b from the left to the right. The refrigerant introduced into the windward heat exchange unit 20 from the communication path 9 flows in the order of the upper first tank unit 21a → the first path 20a → the lower tank unit 22 → the second path 20b → the upper second tank unit 21b. It has become. Then, this refrigerant is led out from the evaporator 1 from an evaporator outlet 8 provided at the right end of the upper second tank portion 21b as the most downstream part of the windward heat exchange part (heat exchange part downstream of the refrigerant) 20. The

  In this evaporator 1, the number of partition portions 14, 24 of both heat exchange units 10, 20 is the same, and the number of meanders (pass number) is the same in both heat exchange units 10, 20. Further, in this evaporator 1, the refrigerant is exchanged between the heat exchangers 10, 20 facing each other when viewed from the direction of wind flow, depending on the setting positions of the evaporator inlet 7, the evaporator outlet 8, the communication passage 9, and the partition parts 14, 24. The distribution direction is reversed. Specifically, in the paths overlapped on the windward side and the leeward side, the refrigerant flow directions are opposite to each other including the upstream and downstream tank portions.

And in this 1st Embodiment, as shown in FIGS. 11-13, at the entrance of upper tank part 11a, 21a of all the downward flow paths 10a, 20a, passage cross-sectional area S0 [== of upper tank part 11a, 21a The throttle portions 34a and 38b in which the passage cross-sectional areas S1 [= π · (d1 / 2) ^2] and S2 [= π · (d2 / 2) ^2] are set smaller than π · (d0 / 2) ^2]. I have. Therefore, in the upper tank portions 11a and 21a of the downward flow paths 10a and 20a, the flow rate of the refrigerant is increased by the throttle action of the inlets 34a and 38b, and the refrigerant flows vigorously toward the downstream side in the tank longitudinal direction. Thus, the refrigerant is positively pushed into the downstream side in the tank longitudinal direction of the upper tank portions 11a, 21a of the downflow paths 10a, 20a, so that the upper tank portions of the downflow paths 10a, 20a as shown in FIG. It is possible to prevent the liquid-phase refrigerant from being biased upstream of the tanks 11a and 21a in the longitudinal direction of the tank. As a result, the refrigerant distribution in the downflow paths 10a and 20a is improved, and a more uniform temperature distribution is obtained.

  In the first embodiment, the passage cross-sectional area of the throttle portion 38b on the downstream side of the refrigerant is set larger than that of the throttle portion 34a on the upstream side of the refrigerant. That is, the passage cross-sectional area d2 of the throttle portion 38b of the inlet of the first path 20a of the leeward heat exchange unit 20 is larger than the passage cross-sectional area d1 of the throttle portion 34a of the inlet of the first path 10a of the leeward side heat exchange unit 10. Is set larger. Thereby, each throttle part 34a, 38b becomes an appropriate throttle amount according to the dryness (wetness) of the refrigerant. This is due to the fact that the refrigerant flowing through the evaporator 1 dries out as it goes downstream, and that the dry refrigerant is lighter in weight and flies far away without reducing the aperture.

"Detailed structure of the evaporator"
Next, the evaporator 1 will be described in more detail with reference to FIGS. 1 to 10 including the structure of the throttle portions 34a and 38b. FIG. 1 is a front view of the evaporator of the embodiment as viewed from the windward side, FIG. 2 is a top view of the evaporator, FIG. 3 is a right side view of the evaporator, and FIG. 4 is a left side view of the evaporator. .

  As shown in FIGS. 1 to 4, the evaporator 1 according to this embodiment includes a plurality of tubes 30 formed by joining a pair of thin metal plates 40 </ b> A and 40 </ b> B in the middle, with outer fins 33 interposed therebetween. It is a stacked type. The outermost metal thin plates 34 and 38, the reinforcing side plate 35, the connector 36, and the like are connected to the outermost tube stacking direction (the outermost side in the evaporator width direction).

  FIG. 10 is a perspective view schematically showing the structure of the tube 30. As shown in FIG. 10b, the tube 30 is configured by joining a pair of thin metal plates 40A and 40B in the middle with the inner fins 61 and 61 sandwiched therebetween. The tube 30 includes two rows of heat exchange passages 31 and 31 for exchanging heat with the air flowing through the outside by flowing a refrigerant therein. The two rows of heat exchange passages 31 and 31 are divided by a partition portion 30a formed in the central portion of the tube 30 along the longitudinal direction, so that the heat exchange passage 31 for the leeward heat exchange portion and the heat for the windward heat exchange portion. It is partitioned from the exchange passage 31. In addition, tank portions 32 and 32 are formed at both ends in the longitudinal direction of the tube 30 so as to project in a cylindrical shape from both ends of each heat exchange passage 31 outward.

  That is, as shown in FIG. 10a, each of the metal thin plates 40A and 40B constituting the tube 30 includes two heat exchange passage recesses 41 and 42 arranged in parallel across the partition 30a and extending in the longitudinal direction. Tank portions 43, 44, 45, and 46 that protrude outwardly from the ends of the heat exchange passage recesses 41 and 42 in a cylindrical shape are provided. The thin metal plate 40A and the thin metal plate 40B have the same shape. The thin metal plate 40A is the metal thin plate 40B, and the thin metal plate 40B is the reverse metal. In the present invention, the pair of thin metal plates 40A and 40B may not have the same shape.

  FIG. 8 is a detailed view of the thin metal plate 40 constituting the tube, and FIG. 9 is a detailed view showing the thin metal plate 50 including a closing portion 51 serving as a partitioning portion. In this evaporator 1, the partition parts 14 and 24 are comprised by utilizing the metal thin plate 50 provided with the obstruction | occlusion part 51 shown in FIG. 9 instead of the metal thin plate 40 shown in FIG. In the thin metal plate 50 of FIG. 9, the same code | symbol is attached | subjected about the structure equivalent to the thin metal plate 40 of FIG.

  FIG. 7 is a view showing the outermost metal thin plate 38 at the right end of the evaporator 1. As shown in FIG. 7, the metal thin plate 34 is provided with communication ports 34 a and 34 b at the upper end and closed portions 34 c and 34 d at the lower end. The closing portions 34c and 34d close the tank portion at the lower end portion of the rightmost metal thin plate 40 in FIGS. The communication port 34 a is provided at a position corresponding to the evaporator inlet 7, and communicates the inlet 7 of the pipe connector 36 and the most upstream portion (upper first tank portion 11 a) of the leeward side heat exchange unit 10. On the other hand, the communication port 34b is provided at a position corresponding to the evaporator outlet 8, and communicates the outlet 8 of the pipe connector 36 with the most downstream portion (upper second tank portion 21b) of the windward heat exchange unit 20. .

  FIG. 6 is a view showing a thin metal plate 38 at the left end of the evaporator 1, and FIG. 5 is a view showing a reinforcing side plate 35 provided on the outer side of the thin metal plate 38 in FIG. As shown in FIG. 6, the metal thin plate 38 at the left end of the evaporator 1 is provided with communication ports 38a and 38b at the upper end and closed portions 38c and 38d at the lower end. The closing portions 38c and 38d close the tank portion at the lower end portion of the leftmost metal thin plate 40 in FIGS. The communication port 38 a corresponds to the refrigerant outlet of the leeward heat exchange unit 10. The communication port 38 b corresponds to the refrigerant inlet of the upwind heat exchange unit 20. The communication port 38a (the refrigerant outlet of the leeward heat exchange unit 10) and the communication port 38b (the refrigerant inlet of the leeward heat exchange unit 20) are stacked on the outer side (left side in the drawing) of the thin metal plate 38. It communicates with the recessed part 35a (9) of (FIG. 5). In FIG. 5, reference numeral 35 b is a reinforcing protrusion provided on the side plate 35, and reference numeral 37 in FIGS. 1 to 3 is a bracket disposed between the side plate 34 and the pipe connector 36.

  In the evaporator 1 having such a configuration, the throttle portion 34a at the inlet of the downward flow path 10a is configured by the communication port 34a of the side plate 34, and the throttle portion 38b at the inlet of the downward flow path 20a is the metal thin plate 38. The communication port 38b.

"effect"
The effects of the first embodiment will be summarized below.

In the evaporator 1 according to the first embodiment, first, the flow direction of the refrigerant in the paths (10a and 20b) (10b and 20a) that are overlapped by the upwind heat exchange unit 20 and the downwind heat exchange unit 10. 14a, the passage cross-sectional area S0 [= π · (d0 of the upper tank portions 11a, 21a at the inlet of the upper tank portions 11a, 21a of all the downflow paths 10a, 20a as shown in FIG. 14a. / 2) passage cross-sectional area S1 than ^2] [= [pi · (d1 / 2) ^2], S2 [= [pi · (d2 / 2) ^2] is small set throttle portion 34a, in the structure provided with the 38b is there.

  Therefore, in the upper tank portions 11a and 21a of the downflow paths 10a and 20a, the flow rate of the refrigerant increases due to the throttle action at the inlet, and the refrigerant flows vigorously toward the downstream side in the tank longitudinal direction. In this way, the refrigerant is positively pushed to the downstream side in the tank longitudinal direction of the upper tank portions 11a, 21a of the downflow paths 10a, 20a, so that the upper tank portions of the downflow paths 10a, 20a as shown in FIG. The liquid refrigerant is prevented from being biased upstream of the tanks 11a and 21a in the longitudinal direction of the tank, thereby improving the refrigerant distribution in the downflow paths 10a and 20a and obtaining a more uniform temperature distribution.

  Further, in this structure, unlike the evaporator as disclosed in Japanese Patent Application Laid-Open No. 2001-74388, it is not a structure in which a throttle portion is provided in the lower tank, so that the lubricating oil contained in the refrigerant stays in the lower tank. Can be prevented.

  Secondly, in the first embodiment, the throttle portions 34a and 38b have a large passage downstream cross-sectional area S1 and S2 (S1 <S2). Thereby, each throttle part 34a, 38b becomes an appropriate throttle amount according to the dryness (wetness) of the refrigerant. This is due to the fact that the refrigerant flowing through the evaporator 1 dries out as it goes downstream, and that the dry refrigerant is lighter in weight and flies far away without reducing the aperture.

  Thirdly, in the evaporator 1 of the first embodiment, the most downstream portion 11b of the heat exchange section on the refrigerant upstream side (in this example, the leeward heat exchange section 10) and the heat exchange passage on the downstream side of the refrigerant (in this example) The communication path 9 that communicates with the most upstream part 21a of the windward side heat exchange part 20) is integrated with a side plate 35 that is attached to the outermost side in the stacking direction and reinforces the strength of the evaporator 1. Therefore, it is not necessary to prepare another member for the communication path, and the manufacturing cost can be reduced.

  Fourth, the evaporator 1 of the first embodiment has a structure in which the heat exchange unit 10 on the refrigerant upstream side is arranged on the leeward side and the heat exchange unit 20 on the refrigerant downstream side is arranged on the leeward side. Therefore, first, the air passing through the heat exchange unit 20 on the downstream side of the refrigerant having a higher refrigerant temperature than the heat exchange unit 10 on the upstream side of the refrigerant is cooled, and then the refrigerant temperature is higher than that of the heat exchange unit 10 on the downstream side of the refrigerant. The cooled air can be further cooled by the heat exchanger 10 on the upstream side of the refrigerant having a low temperature. That is, it is possible to cool the air that is ventilated step by step in the heat exchange units 20 and 10 on the leeward side and the leeward side, and the heat exchange units 20 and 10 on the leeward and leeward sides can be efficiently used without waste. Thereby, the cooling performance is increased.

  Hereinafter, other embodiments of the present invention will be described. In addition, about the structure which is the same as that of 1st Embodiment, or similar, the same code | symbol is attached | subjected and description of a structure and its effect is abbreviate | omitted.

  Second Embodiment: FIG. 15 shows a second embodiment of the present invention. In the evaporator 1D of the second embodiment, the number of heat exchange passages in the upflow paths 10b and 20b is set to be smaller than the number of heat exchange passages in the downflow paths 10a and 20a. Thereby, the tank longitudinal direction size of upflow path 10b, 20b is smaller than downflow path 10a, 20a.

  With such a configuration, in addition to the effects of the first embodiment, it is possible to increase the amount of liquid phase refrigerant on the upstream side in the tank longitudinal direction, where the liquid phase refrigerant tends to be insufficient in the upward flow paths 10b and 20b, and the upward flow path 10b. , 20b can improve the refrigerant distribution. Thereby, a more uniform refrigerant distribution can be obtained by overlapping the windward side heat exchange unit 20 and the leeward side heat exchange unit 10.

  Third Embodiment: In the first and second embodiments described above, the evaporator in which the heat exchange units 10 and 20 are set to two passes has been described. However, in the present invention, FIG. You may set to the number of passes of 3 passes or more like the evaporator 1E of 3rd Embodiment shown. In this case, the same effect as that of the first embodiment can be obtained.

  In the case where the throttle unit is set in the intermediate portion in the stacking direction of the evaporator 1E as in the third embodiment, for example, the throttle unit 72 is provided in the tank unit 46 (or other tank unit) as shown in FIG. This can be dealt with by laminating the metal thin plate 50 </ b> E having a predetermined position. In addition, in the metal thin plate 50E shown in FIG. 17, about the structure equivalent to the metal thin plate 50 shown in FIG. 9, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  Further, depending on the position of the throttle portion, a thin metal plate 40E having the throttle portion 71 in the tank portion 46 (other tank portion may be used) as shown in FIG. 18 may be used. In addition, in the metal thin plate 40E of FIG. 18, about the structure equivalent to the metal thin plate 40 shown in FIG. 8, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  In short, the present invention is such that the two heat exchange parts are stacked in the direction of ventilation, and the flow direction of the refrigerant is reversed between the path of the upwind heat exchange part and the path of the leeward heat exchange part facing each other. It is a set evaporator, and is characterized in that a throttle portion having a passage cross-sectional area set smaller than a passage cross-sectional area of the upper tank is provided at the inlet of the upper tank of all the downflow paths. Therefore, in the upper tank of the downflow path, the flow rate of the refrigerant increases due to the throttle action of the inlet, and the refrigerant flows vigorously toward the downstream side in the tank longitudinal direction. In this way, liquid refrigerant is prevented from being biased to the upstream side in the tank longitudinal direction of the upper tank of the downflow path by positively pushing the refrigerant into the tank longitudinal direction downstream side of the upper tank of the downflow path. Is done. Thereby, the refrigerant distribution in the downward flow path is improved, and a more uniform temperature distribution is obtained.

FIG. 1 is a front view of the evaporator according to the first embodiment of the present invention as viewed from the windward side. FIG. 2 is a top view of the evaporator. FIG. 3 is a right side view of the evaporator. FIG. 4 is a left side view of the evaporator. FIG. 5 is a view showing a left side plate of the evaporator. FIG. 6 is a view showing the outermost metal thin plate at the left end of the evaporator. FIG. 7 is a view showing an outermost metal thin plate at the right end of the evaporator. FIG. 8 is a view showing a metal thin plate constituting the tube of the evaporator. FIG. 9 is a view showing a thin metal plate that is integrally provided with a partition portion. FIG. 10 is a perspective view schematically showing the structure of a tube formed by joining a pair of metal thin plates together. FIG. 11 is a vertical sectional view schematically showing the structure of the leeward heat exchanger of the evaporator according to the first embodiment. FIG. 12 is a vertical sectional view schematically showing the structure of the windward heat exchanger of the evaporator. FIG. 13 is a perspective view schematically showing the flow of refrigerant in the evaporator. FIG. 14 is a schematic view showing the distribution of the liquid-phase refrigerant in the evaporator. FIG. 15 is a diagram schematically showing an evaporator according to a second embodiment of the present invention. FIG. 16 is a diagram schematically showing an evaporator according to a third embodiment of the present invention. FIG. 17 is a view showing an example of a thin metal plate provided with a partition part and a throttle part used in the evaporator according to the third embodiment. The figure which shows the other example of a metal thin plate provided with a partition part and an aperture | diaphragm | squeeze part. FIG. 19 is a schematic view showing an example of a conventional evaporator. FIG. 20 is a schematic view showing the distribution of the liquid refrigerant in the evaporator of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1D, 1E ... Evaporator 9 ... Communication path 10 ... Heat exchange part on the leeward side (heat exchange part on the refrigerant upstream side)
10a ... 1st pass (downward flow pass)
10b ... 2nd pass (upflow path)
DESCRIPTION OF SYMBOLS 11 ... Upper tank 11a ... 1st tank part 11b ... 2nd tank part (the most downstream part of a heat exchange part)
DESCRIPTION OF SYMBOLS 12 ... Lower tank 20 ... Heat exchange part 20 ... Upwind heat exchange part 20a ... 1st path | pass (downflow path)
20b ... 2nd pass (upflow path)
21 ... Upper tank 21a ... 1st tank part (the most upstream part of a heat exchange part)
21b ... Second tank part 22 ... Lower tank 24 ... Partition part 30 ... Tube 30a ... Partition part 31, 31 ... Heat exchange passage 32, 32, 32, 32 ... Tank part 33 ... Outer fin 34 ... Side plate 34a ... Communication port (Aperture part)
35 ... side plate 35a ... concave part (communication part)
38b ... Communication port (throttle part)
40 (40A, 40B) ... Metal thin plate 40E ... Metal thin plate 41, 42 ... Recess for heat exchange passage 43-46 ... Tank part 50 ... Metal thin plate 50E ... Metal thin plate 71 ... Restriction part 72 ... Restriction part S0 ... Passage cross-sectional area S1 ... Cross sectional area S2 ... Cross sectional area

Claims (4)

A plurality of heat exchange passages (31, 31) that extend in the vertical direction and flow refrigerant inside are stacked in multiple stages, and the refrigerant from the heat exchange passages are merged and distributed at the upper and lower ends of the multi-stage heat exchange passages (31, 31). A heat exchange section (10, 20) provided with tanks (11, 12, 21, 22)
In the evaporator (1, 1D, 1E) arranged in two layers with the heat exchange part (10, 20) in the ventilation direction,
A plurality of paths (10a, 10b,...) (20a, 20b,...) So that each refrigerant exchange direction (10, 20) is reversed in the opposite heat exchange sections (10, 20). The evaporator (1, 1D, 1E) divided into
At the entrance of the upper tank (11a, 21a,...) Of all the downflow paths (10a, 20a,...), The passage sectional area is larger than the passage sectional area (S0) of the upper tank (11a, 21a,. An evaporator (1, 1D, 1E) provided with a throttle part (34a, 38b, 71, 72) in which (S1, S2) is set small. An evaporator (1D) according to claim 1,
The evaporator (1D) characterized in that the number of heat exchange passages in the upward flow path (10b, 20b) is set smaller than that of the downward flow path (10a, 20a). The evaporator (1, 1D, 1E) according to claim 1,
It is a structure in which the refrigerant circulated through one of the heat exchange units (10) is directly circulated through the other heat exchange unit (20),
The communication path (9) that connects the most downstream part (12b) of the heat exchange part (10) on the refrigerant upstream side and the most upstream part (22a) of the heat exchange part (20) on the refrigerant downstream side is connected to the evaporator ( An evaporator (1, 1D, 1E) characterized in that it is integrally formed on a side plate (35) attached to the outermost side in the stacking direction of 1) and reinforcing the strength of the evaporator (1). The evaporator (1, 1D, 1E) according to claim 1,
It is a structure in which the refrigerant circulated through one of the heat exchange units (10) is directly circulated through the other heat exchange unit (20),
An evaporator (1, 1D, 1E) characterized in that the heat exchanger (10) on the upstream side of the refrigerant is disposed on the leeward side and the heat exchanger (20) on the downstream side of the refrigerant is disposed on the leeward side.

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