JPH03129270A - Lamination type evaporator - Google Patents

Abstract

PURPOSE:To sufficiently heat-exchange a liquid refrigerant with air to evaporate so as to prevent the outflow of the refrigerant by allowing a refrigerant to meander to flow toward the flow direction of air. CONSTITUTION:A liquid refrigerant allowed to flow in from an introduction pipe 8 is allowed to flow in first refrigerant passages 4-4c connected transversely and meander to flow in the direction shown by arrow marks in second refrigerant passages 6-6c a plurality of times to always become a counterflow to the flow of air. Accordingly, the refrigerant is allowed to meander to flow in the refrigerant passages 6-6c to evaporate and is gradually phase-changed from liquid to gas to increase a specific volume. Thereby the whole refrigerant is evaporated so as to prevent the outflow of the liquid refrigerant.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a stacked evaporator used in a private air conditioner or the like.

[Conventional technology]

Conventional stacked evaporators are designed to cause the refrigerant flowing in from the leeward side to flow as counter-currently as possible to the air, as described in Japanese Utility Model Application Publications No. 50-154774 and No. 63-173673. It has been devised.

That is, FIG. 4 of Utility Model Application Publication No. 60-154774.

As shown in Figure 1 of Japanese Utility Model Application Publication No. 63-173673, the refrigerant is made a U-turn from the leeward side to the windward side, so that the flow of the refrigerant becomes a counterflow, thereby improving thermal efficiency.
In reality, there are only two opportunities for the liquid refrigerant to obtain the amount of heat required for evaporation from the air, and as a result, if the temperature difference between the temperature of the liquid refrigerant and the temperature of the incoming air is small, the liquid refrigerant will not fully evaporate. There was a problem with the data being leaked.

On the other hand, as another method for improving the heat exchange coefficient of a stacked evaporator, there is a method of flowing a large amount of liquid refrigerant on the air inflow side, and according to Fig. 1 of Japanese Utility Model Application No. 175769/1982,
A large amount of liquid refrigerant exchanges heat with the highest temperature air to promote evaporation, and the refrigerant with increased specific volume can flow through passages with a wide cross-sectional area.

Improved heat exchange efficiency 6 However, in the heat exchanger having the above structure, the flow of the refrigerant is not a counterflow to the flow of air, but a meandering flow in a direction perpendicular to the flow of air.

There was a problem in which the liquid refrigerant on the leeward side could not be completely evaporated and flowed out of the evaporator.

[Problem to be solved by the invention]

In all of the above conventional techniques, no consideration is given to sufficiently exchanging heat with air to evaporate the liquid refrigerant, and there is a problem in that the liquid refrigerant flows out.

SUMMARY OF THE INVENTION An object of the present invention is to provide a stacked evaporator that can sufficiently exchange heat with air to evaporate liquid refrigerant and prevent the liquid refrigerant from flowing out.

Another object of the present invention is to provide an flF type evaporator having a structure capable of improving heat exchange efficiency.

[Means to solve the problem]

In order to achieve the above object, the refrigerant is made to flow in a meandering manner multiple times in the direction of air inflow.

Furthermore, in order to effectively exchange heat, the refrigerant is caused to flow in a meandering manner multiple times, and the cross-sectional area of the refrigerant passage is gradually increased in the direction in which the refrigerant flows.

Furthermore, in order to achieve the above object, the refrigerant is caused to flow in a meandering manner multiple times, and the width of the refrigerant passage is gradually increased.

[Effect]

The refrigerant that has flowed into the heat exchanger flows in a countercurrent flow toward the direction in which the air flows, and it flows in a meandering manner multiple times. This makes it easier for the liquid refrigerant to evaporate, resulting in smooth heat exchange efficiency.

In addition, the refrigerant flows in a meandering manner multiple times as a countercurrent flow toward the inflow direction of the air, and the passage resistance gradually decreases.

Therefore, it is ensured that all liquid refrigerant undergoes heat exchange.

(Example) An example of the present invention will be described below with reference to FIGS. 1 to 4.

As shown in Figures 3 and 4, this integral calendar type evaporator consists of a pair of tube plates L and 11 made of aluminum.
and a corrugated fin 2 disposed between the tube plates and fixed by brazing material, and the tube plate assembly 3 is arranged in parallel and connected to 1 refrigerant passage 4, a second refrigerant passage 6 with a vertical axis formed between the tube plate assemblies 3 and between the side plates 5.5a, a side cover 7.7a, and the side cover 7.7a. 7a, and is composed of a refrigerant introduction pipe 8 connected to the introduction side of the first refrigerant passage 4, and a discharge pipe 9 connected to the discharge side of the first refrigerant passage 4, which are connected to each other. After the above-mentioned parts are stacked on top of each other, they are hermetically joined together by brazing filler metal or the like in a furnace.

FIG. 1 is a front view of the tube plate 1, showing one plate molded.

An aluminum plate 1 punched into a rectangular shape has a peripheral partition ula formed in a convex shape around the periphery, and second refrigerant passages 6 to 6c connected alternately above and below the peripheral partition wall and having a vertical axis.
A plurality of intermediate partition walls 1b are provided. The passage width °C of the second refrigerant passage 6 gradually increases in the direction in which the refrigerant flows.

In addition, beats 1c are formed in the refrigerant passages 6 to 6c toward the passages to prevent uneven flow of the refrigerant and to improve pressure resistance of the evaporator.

In the above configuration, as shown in FIG. 2, the liquid refrigerant flowing in from the introduction pipe 8 flows horizontally in the first refrigerant passages 4 to 4c, and flows in the direction shown by the arrow in the second refrigerant passages 6 to 6c. The flow meanderes multiple times, always creating a counterflow to the air flow.

Therefore, when the refrigerant flows in a meandering manner through the refrigerant passages 6 to 6c, the refrigerant is evaporated and its phase gradually changes from liquid to gas, and its specific volume increases.

Generally, if the cross-sectional area of the refrigerant passage remains constant from the beginning to the end of the refrigerant flow, the specific volume will increase as the refrigerant changes phase and the proportion occupied by gas refrigerant increases. Regardless, the cross-sectional area of the passage does not increase, creating resistance to the flow of refrigerant.

As a result, the flow rate of the refrigerant decreases, and the cooling capacity of the evaporator decreases. However, in the present invention, the widths 01 to Q4 of the refrigerant passages divided by the partition walls 1b of the tube plate 1 are gradually increased. Since the passage cross-sectional area is gradually increased,
Contrary to the conventional art, the increase in resistance to the flow of refrigerant can be reduced.

A second embodiment of the present invention will be explained with reference to FIGS. 5 and 6. Similar to FIG. 1, FIGS. 5 and 6 show the tube plate of the stacked evaporator shown in FIG. 3.

(In addition, in FIG. 5 and FIG. 6, the beat 1c of the tube plate 1 shown in FIG. 1 is omitted.) In FIG. 1d each opening length wt l Wl y
The size of W3 is gradually increased in the direction in which the refrigerant flows as indicated by the arrow. As described above, the phase of the refrigerant gradually changes from liquid to gas, and its specific volume increases. If all the opening lengths of the openings 1d of the partition wall 1b are the same, there will be flow resistance, the flow rate of the refrigerant will decrease, the amount of heat exchange will decrease, and the cooling capacity of the evaporator will decrease. Therefore, the opening lengths Wl, Wl of the opening 1d of the partition wall 1b.

By gradually increasing the size of W, it is possible to reduce the increase in resistance to the flow of the refrigerant.

Further, the opening lengths wl, Wl, and W3 of the opening 1d of the partition wall 1b are gradually changed in proportion to the rate of increase in the specific volume as the liquid refrigerant gradually changes phase to a gaseous refrigerant. By increasing the refrigerant resistance, it is possible to prevent an increase in the resistance of the refrigerant. Width w1 of the opening 1d
+ Wl HW3 is the width of the front passage L + r f
), z, is designed to be at least larger than Q3.

According to the first embodiment of the present invention, the flow of the refrigerant is a counterflow toward the inflow direction of the air, and the refrigerant flows in a meandering manner multiple times, so that the refrigerant easily evaporates and gradually changes from a liquid to a gas. This can prevent liquid refrigerant from flowing out.

Also, the width of the liquid refrigerant passage in the discharge direction.

Since it is gradually enlarged, it is possible to prevent an increase in resistance to the flow of refrigerant and improve heat exchange efficiency.

Furthermore, in this embodiment, the tank portion that does not exchange heat, represented by the first refrigerant passages 4 to 4c, has only one of the upper end and the lower end, so if the front area is the same,
A large heat transfer area can be obtained.

From a structural point of view, since the tube plate is simply formed by press working and then laminated and brazed, the width and length of the refrigerant passage can be set arbitrarily, so there is an advantage that the tube plate can be configured as desired.

Note that FIG. 6 differs from FIG. 5 only in that the first refrigerant passages 4 to 4c are located on the lower side, and the effect is the same as that in FIG. 5.

〔Effect of the invention〕

According to the present invention, since the refrigerant is made to meander multiple times so as to flow in the direction of air inflow, it is possible to evaporate all the refrigerant and prevent the liquid refrigerant from flowing out.

Further, by gradually increasing the cross-sectional area of the refrigerant passage in the discharge direction, it is possible to suppress an increase in resistance to the flow of the refrigerant and improve the heat exchange efficiency.

[Brief explanation of the drawing]

Figure 1 is a front view of the tube plate, Figure 2 is a schematic diagram showing the refrigerant flow path, Figure 3 is a perspective view, Figure 4 is a sectional view of the main part of Figure 3, and Figure S is another diagram. FIG. 6 is a front view of the tube plate in another embodiment. 1... Tube plate, 1a... Surrounding wall, 1b.
・・Partition wall, 1c・=bead, 4, 4a, 4b, 4cm
First refrigerant passage, 6, 6a, 6b, 6
c-Second refrigerant passage. Plate 20 Fable 6

Claims (1)

[Claims] By aligning one or two molded plates,
A tube element is constructed in which a pair of tank parts or more and a U-shaped fluid passage communicating with the tank parts are formed at either the upper end or the lower end, and the tube elements and corrugated fins are alternately stacked. A stacked evaporator comprising a stacked evaporator, characterized in that the refrigerant flows in a meandering manner multiple times in the direction of air inflow. 2. The stacked evaporator according to claim 1, wherein the cross-sectional area of the refrigerant passage is gradually increased in accordance with the direction in which the refrigerant flows. 3. The stacked evaporator according to claim 1, wherein the refrigerant passage has a passage cross-sectional area that changes according to a change in the specific volume of the refrigerant. 4. The stacked evaporator according to claim 1, wherein the cross-sectional area of the refrigerant passage is changed by gradually increasing the width of the passage. 5. The stacked evaporator according to any one of claims 1 to 4, characterized in that the length of the opening of the partition that partitions the refrigerant passage is gradually increased. 6. The stacked evaporator according to claim 1, wherein the cross-sectional area of the refrigerant passage is gradually increased in the flow direction of the refrigerant in proportion to the rate of increase in the specific volume of the refrigerant. 7. The laminated evaporator according to any one of claims 2 to 6, wherein the refrigerant is meandered a plurality of times in the direction of air inflow, and the number of times is an odd number of three or more times. 8. The stacked evaporator according to claim 7, wherein the refrigerant is meandered multiple times in the direction of air inflow and the passage resistance of the refrigerant is gradually reduced.