JP2003161547A - Plate type heat exchanger for evaporator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plate type heat exchanger for an evaporator that improves heat exchange efficiency by preventing a partial increase of liquid mist of a refrigerant in a part in a housing and effectively working all heat transfer surfaces. <P>SOLUTION: The plate type heat exchanger 1X for an evaporator comprises the housing 13 having a refrigerant inlet 11 and a refrigerant outlet 12, and a plurality of hollow plates 14 arranged in the housing to divide the internal space of the housing 13 into a plurality of small passages 15 that deflect a refrigerant from the refrigerant inlet 11 to the refrigerant outlet 12, to form passages for a cooled fluid separated from the refrigerant and to form heat transfer surfaces for transferring heat from the refrigerant. Thin tubes 2A to 2C and a through-hole 3 are provided to divert a refrigerant from the refrigerant inlet 11 into a plurality of passages and individually lead it in an evenly dispersed manner from a position near the refrigerant inlet 11 to a spaced position in a space portion 16 on an inlet side of the small passages 15. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plate heat exchanger for an evaporator used in an air conditioner, a refrigerator or the like.

[0002]

2. Description of the Related Art For example, as shown in FIG.
Basically, it is formed by a refrigerant circulation flow path e including a compressor a, a condenser b, an expansion valve c and an evaporator d. As is well known, the refrigerant gas compressed by the compressor a is deprived of heat by, for example, cooling water by heat exchange in the condenser b, and the temperature of the cooling water is raised. The refrigerant deprived of heat in the condenser b exits the condenser b in a liquid state and reaches the expansion valve c,
In the process of passing through the expansion valve c, isenthalpic expansion is performed, and a partial gas state is established, resulting in a gas-liquid two-phase state. The gas-liquid two-phase refrigerant is heat-exchanged in the evaporator d,
The heat is taken from the object to be cooled, for example, water, and all of them are in a gas state, while the water is chilled water. Further, the refrigerant that has turned into a gas state in the evaporator d returns to the compressor a, is compressed again, and is repeatedly circulated in the circulation passage e described above.

By the way, various types of evaporators have been conventionally used as the evaporator d. For example, FIG. 7 shows an evaporator plate heat exchanger 10X, which is one of them. This evaporator plate heat exchanger 10X includes a housing 13 having a refrigerant inlet 11 at a lower portion and a refrigerant outlet 12 at an upper portion, and a plurality of passages for a fluid to be cooled provided therein. The hollow plate 14 of FIG. Then, the refrigerant in the gas-liquid two-phase state that has passed through the expansion valve c described above flows into the housing 13 from the refrigerant inlet 11 and flows into each of the small flow paths 15 formed on both sides of each hollow plate 14. Dispersed and flow upward, small flow path 15
In the outlet side space part of the above, they join again and flow out from the refrigerant outlet 12 toward the compressor a. In this way, gas-liquid 2
The refrigerant in the phase state has a refrigerant inlet 11 in the housing 13.
Via one refrigerant passage, that is, the inlet side space portion 1 of the small passage 15.
In the process of flowing into the cooling pipe 6, turning 90 degrees, passing through the small flow path 15, and then flowing out of the refrigerant outlet 12, heat is exchanged with the fluid to be cooled through the hollow plate 14 forming the heat transfer surface. ,
While the fluid to be cooled is cooled, heat is taken from the fluid to be cooled so that the fluid to be cooled is completely vaporized.

FIG. 8 shows another conventionally known plate heat exchanger for evaporator 10Y. In this plate heat exchanger for evaporator 10Y, the refrigerant in the gas-liquid two-phase state is introduced into the refrigerant inlet 11 From the above-mentioned evaporator to the inlet side space portion 16 of the small flow passage 15 partitioned by the hollow plate 14 via a single distribution pipe 18 having a plurality of small holes 17 formed therein. It has the same structure as the plate heat exchanger 10X. Then, the refrigerant from the refrigerant inlet 11 is distributed from each small hole 17 of the distribution pipe 18 forming one refrigerant flow path, flows out, and flows into each of the small flow paths 15.

FIG. 9 shows another known plate heat exchanger for an evaporator 10Z, which is a plate heat exchanger for an evaporator 10Z. In the evaporator plate heat exchanger 10Z, the refrigerant in the gas-liquid two-phase state is introduced into the refrigerant. The inlet side space portion 1 of the small flow passage 15 which is jetted from the perforated plate 19 provided in 11 to form one refrigerant flow passage.
6 has the same structure as the above-described evaporator plate heat exchanger 10X except that the heat is introduced into the plate heat exchanger 6. Then, the perforated plate 19 disturbs the liquid mist of the refrigerant to flow into the upper writing side space 16 of the small channel 15 and guides it to the small channel 15.

[0006]

In any of the plate heat exchangers for evaporators 10X, 10Y, 10Z described above, the refrigerant is introduced from the refrigerant inlet 11 into the small passage 15 through one refrigerant passage. It is structured and this small channel 1
When flowing into No. 5, the flow direction is changed by 90 ° all at once. Therefore, due to the action of the inertia of the liquid mist of the refrigerant, the liquid mist is biased to the farthest portion from the refrigerant inlet 11 in the inlet side space 16 of the small flow path 15,
This portion becomes liquid-rich. As a result, the ratio of the liquid in the refrigerant flowing into the innermost small flow path 15 furthest away from the refrigerant inlet 11 becomes large, and the heat transfer surface of the hollow plate 14 cannot be effectively operated. There was a problem that the exchange efficiency was lowered. The present invention has been made to eliminate the above-mentioned conventional problems, and prevents the liquid mist of the refrigerant from increasing in one portion in the housing, and all the heat transfer surfaces are effective. It is intended to provide a plate type heat exchanger for an evaporator, which can be improved in heat exchange efficiency by improving the heat exchange efficiency.

[0007]

In order to solve the above-mentioned problems, the first aspect of the present invention is to provide a housing having a refrigerant inlet and a refrigerant outlet, which is provided inside the housing, and which is provided from the refrigerant inlet. While dividing the space in the housing into a plurality of small flow paths that redirect the refrigerant to reach the refrigerant outlet, form a flow path for the cooled fluid that is isolated from this refrigerant, and In a plate-type heat exchanger for an evaporator having a plurality of hollow plates that form a heat transfer surface for transmitting heat from, the refrigerant from the refrigerant inlet is divided into a plurality of flow paths, and the small flow paths are provided. The inlet side space is provided with a distribution means for evenly distributing and separately guiding from a position close to the refrigerant inlet to a position distant from the refrigerant inlet.

According to a second aspect of the present invention, in addition to the structure of the first aspect, the distribution means divides the inlet space into a plurality of compartments communicating with the small flow passage, and the refrigerant flow. It is configured to have a flow-dividing flow path that separately introduces a refrigerant from the inlet to each of the compartments.

According to a third aspect of the invention, in addition to the structure of the first aspect, the distribution means is provided with an outflow hole for letting out a refrigerant from the inlet side space portion to the small flow passage, and from the refrigerant inlet port. It has a plurality of thin tubes that divide the refrigerant and guide it separately to the outflow holes, and the outflow holes are even from the position near the refrigerant inflow port in the inlet space to a position apart from the refrigerant inflow port. It is configured so as to be dispersed and located.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. 1 to 3 show an evaporator plate heat exchanger 1X according to the present invention, and portions common to the evaporator plate heat exchanger 10X described above are designated by the same reference numerals and description thereof is omitted. In the evaporator plate heat exchanger 1X, the refrigerant inlet 11 holds three thin tubes 2A, 2B, and 2C extending into the housing 13 from the refrigerant inlet 11, and holds one through hole 3. The holding plate 4 is provided. Further, collision plates 6A, 6B and 6C for dividing the inlet side space 16 into compartments 5A, 5B, 5C and 5D are provided, and the collision plate 6A closest to the refrigerant inlet 11 is the thin tube 2.
A, 2B and 2C are penetrated, the intermediate collision plate 6B penetrates the thin tubes 2B and 2C, and the collision plate 6C farthest from the refrigerant inlet 11 penetrates only the thin tube 2C.
Then, the thin tubes 2A, 2B and 2 held by the holding plate 4
C and the through hole 3 form a branch flow passage, and these and the collision plates 6A, 6B, and 6C form a distribution means.

Therefore, there is a one-to-one relationship between each of the compartments 5A, 5B, 5C and 5D and the refrigerant flow path communicating with each of them, that is, the through hole 3, and the thin tubes 2A, 2B and 2C. The depth dimension of each of the compartments 5A, 5B, 5C, and 5D (for example, in the case of the compartment 5B, the dimension indicated by L in the figure) is the dimension of the diameter of each of the collision plates 6A, 6B, and 6C (see FIG. It is preferable that the size is equal to or less than the dimension indicated by medium D (that is, D ≧ L). Further, the present invention does not limit the number of the thin tubes 2A, 2B and 2C, the compartments 5A, 5B, 5C and 5D, the hollow plate 14 and the small flow paths 15 at all, but the number of thin tubes is about The number of chambers is 11
It is preferable to set the diameter to about 3 to 10 in consideration of the diameter of the pipe and the diameter of the thin pipe.

Then, the refrigerant in the gas-liquid two-phase state from the expansion valve c described above is passed through the thin tubes 2A, 2B and 2C and the through hole 3.
And is guided to the inside of the inlet space 16, and the refrigerant is evenly guided to each of the small flow paths 15 by the collision plates 6A, 6B and 6C. That is, the refrigerant that has passed through the through holes 3 collides with the collision plate 6A and is guided to the small flow path 15 that communicates with the compartment 5A closest to the refrigerant inlet 11, and the refrigerant that has passed through the thin tube 2A collides with the collision plate 6B. And is guided to the small flow path 15 leading to the next compartment 5B, and the refrigerant passing through the narrow tube 2B collides with the collision plate 6C and is guided to the small flow path 15 leading to the next compartment 5C, The refrigerant that has passed through the narrow tube 2C collides with the inner wall of the housing 13 and is guided to the small flow path 15 that communicates with the farthest compartment 5D from the refrigerant inlet 11. With the above configuration, the refrigerant evenly distributed from the refrigerant inlet 11 is introduced into the compartments 5A, 5B, 5C, and 5D, and the refrigerant is evenly introduced into the small flow paths 15 without being biased. Therefore, heat exchange can be efficiently performed in the hollow plate 14.

FIGS. 4 and 5 show another plate heat exchanger for evaporator 1Y according to the present invention, in which parts common to those of the plate heat exchanger for evaporator 10X described above are designated by the same reference numerals. The description is omitted. In this evaporator plate heat exchanger 1Y, four thin tubes 7A, 7B extending from the refrigerant inlet 11 into the housing 13 are provided.
A holding plate 8 that holds 7C and 7D in a penetrating manner is provided. Further, the outflow holes 9A, 9B, 9C and 9 are provided at the respective tip portions of the thin tubes 7A, 7B, 7C and 7D.
D is bored, and each of the outflow holes 9A, 9B, 9C, and 9D is a space portion on the inlet side of the small flow path 15 and is separated from the vicinity of the refrigerant inlet 11 and the refrigerant inlet 11. The refrigerant is evenly distributed to the different positions, and the refrigerant is made to flow toward each of the small flow paths 15. In the case of the evaporator plate heat exchanger 1Y, the distribution means is formed by the thin tubes 7A, 7B, 7C and 7D having the outflow holes 9A, 9B, 9C and 9D.

With such a configuration, similarly to the above, the equally distributed refrigerant is introduced from the refrigerant inlet 11 to the respective inlet sides of the small flow paths 15 and is not biased to any of the small flow paths 15. , The refrigerant is evenly introduced to each of them, and the heat exchange is efficiently performed in the hollow plate 14. In the evaporator plate heat exchanger 1X as well, the thin tubes 7A, 7A
Although the example in which B, 7C and 7D are provided is shown, the number thereof is not limited at all.

[0015]

As is apparent from the above description, according to the present invention, in order to allow the refrigerant to flow into the inlet side space portion of the small flow passage from the refrigerant inlet, the refrigerant is introduced from a position close to the refrigerant inlet. It is formed so that it is evenly dispersed to a position apart from the coolant inlet port and guided separately, and the dispersed coolant is caused to flow into each small flow path. For this reason, it is possible to prevent the liquid mist of the refrigerant from increasing in one portion in the housing and to effectively operate all the heat transfer surfaces to improve the heat exchange efficiency. .

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an outline of an evaporator plate heat exchanger according to the present invention.

FIG. 2 is an enlarged partial sectional view of a refrigerant inflow portion in the evaporator plate heat exchanger shown in FIG.

3 is a sectional view taken along line III-III in FIG.

FIG. 4 is an enlarged partial cross-sectional view of a refrigerant inflow portion of another evaporator plate heat exchanger according to the present invention.

5 is a sectional view taken along line VV of FIG.

FIG. 6 is a diagram showing a basic configuration of a refrigerator.

FIG. 7 is a cross-sectional view showing an outline of a conventional plate heat exchanger for an evaporator.

FIG. 8 is a cross-sectional view showing the outline of another conventional plate heat exchanger for an evaporator.

FIG. 9 is a cross-sectional view showing the outline of still another conventional plate heat exchanger for an evaporator.

[Explanation of symbols]

1X, 1Y Plate heat exchanger for evaporator 2A, 2B, 2C thin tubes 3 through holes 4 holding plate 5A, 5B, 5C, 5D Compartments 6A, 6B, 6C Collision plate 7A, 7B, 7C, 7D thin tubes 8 holding plate 9A, 9B, 9C, 9D Outflow hole 11 Refrigerant inlet 12 Refrigerant outlet 13 housing 14 Hollow plate 15 small channels 16 Entry side space

Claims (3)

[Claims] 1. A housing having a refrigerant inlet and a refrigerant outlet, and a plurality of small streams provided inside the housing for redirecting the refrigerant from the refrigerant inlet to reach the refrigerant outlet. A plurality of hollow plates that divide the space in the housing into a passage, form a flow path for the cooled fluid that is isolated from the refrigerant, and form a heat transfer surface that transfers heat from the refrigerant. In the evaporator plate heat exchanger provided, the refrigerant from the refrigerant inlet is divided into a plurality of passages, and the refrigerant is introduced from a position near the refrigerant inlet in the inlet side space of the small passage. A plate-type heat exchanger for an evaporator, characterized in that a distribution means is provided to evenly disperse it to a position apart from the inlet and guide it separately. 2. A collision plate for dividing the inlet side space into a plurality of compartments communicating with the small flow path, and the distributor separately supplies a refrigerant from the refrigerant inlet to each of the compartments. It is formed from the branch flow channel which leads.
The plate-type heat exchanger for an evaporator according to. 3. The distribution means is provided with an outflow hole for outflowing a refrigerant from the inlet side space portion to the small flow path, the refrigerant is diverted from the refrigerant inflow port, and the outflow hole is separately provided in the outflow hole. It has a plurality of thin tubes for guiding, and the outflow holes are located evenly distributed from a position close to the refrigerant inlet in the inlet side space to a position apart from the refrigerant inlet. The plate heat exchanger for an evaporator according to claim 1.