JPH09273829A - Integrated piping for refrigerating cycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the piping construction around a heat exchanger of an air conditioner and reduce the power consumption by a method wherein a refrigerant distributor to distribute refrigerant in between two flat plate, a distribution pipe to lead the refrigerant from the refrigerant distributor to a heat exchanger, a part of a bend pipe of the heat exchanger and a header are integrally formed into one piece. SOLUTION: An end plate 4 of a heat exchanger is composed of two plates, and grooves to form distribution pipes 2-1, 2-2, 2-3 and 2-4, grooves to compose bend pipes 5-1, 5-2, 5-3, and 5-4, and an inlet of a refrigerant distributor 1 are formed on one side. Grooves to compose the refrigerant distributor 1, an opening for the end of a heat transfer tube and a groove to compose a header 7 are formed on the other side. The two plates are connected by such a mean as brazing with a brazing filler metal in a furnace, and cooling paths 1, 2-1, 2-2, 2-3 and 2-4 are form by the two plates.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigeration cycle for refrigeration and air conditioning, and more particularly to simplification of a refrigerant pipe of the refrigeration cycle.

[0002]

2. Description of the Related Art An example of a piping system around a cooling heat exchanger of an air conditioning refrigeration cycle is shown in FIG. In FIG. 12, 1 is a refrigerant distributor, 2-1, 2-2, 2-3, 2-4 are distribution pipes, 3 is a heat exchanger, 4 is an end plate of the heat exchanger, 5-1 and 5-2. , 5-
3, 5-4 are bend tubes of heat exchangers, 6-1-1 and 6-2
-1, 6-3-1, 6-4-1, 6-1-4, 6-2-
4, 6-3-4, 6-4-4 are heat transfer tubes of a heat exchanger, 7 is a header, 8 is an expansion valve, 9 is an expansion valve inlet tube, 10 is an inlet tube to the refrigerant distributor, and 11 is a header. Outflow pipe, 12 denotes the flow of air entering the heat exchanger. The liquid-state refrigerant flowing from the expansion valve inlet pipe 9 into the expansion valve 8 is decompressed into a gas-liquid two-phase flow state and flows into the refrigerant distributor 1 from the inflow pipe 10 to the refrigerant distributor. The flow of the refrigerant is divided into four flows having the same gas-liquid ratio by passing through the refrigerant distributor 1, and the distribution pipes 2-1, 2-2, 2-3, 2-4 are respectively divided.
Flow through the heat transfer tubes 6-1-1, 6-2-1, 6 of the heat exchanger
It flows into the heat exchanger 3 from 3-1 and 6-4-1. In order to fully exhibit the performance of the heat exchanger, the distribution pipe resistance is designed to be different depending on the wind velocity distribution of the air flow 12 flowing into the heat exchanger, the arrangement of the heat transfer tubes, and the like. The refrigerant evaporates when heat is applied from the air flow 12 orthogonal to the heat transfer tubes in the heat exchanger, and the liquid refrigerant is completely vaporized, or most of the liquid refrigerant is vaporized. 6
It flows out from 1-4, 6-2-4, 6-3-4, 6-4-4, gathers at the header 7, and goes out from the outflow pipe 11. In such a conventional technique, since the pipe from the inflow pipe 10 to the refrigerant distributor to the header 7 has a refrigerant pipe shape arranged in a three-dimensional space, it takes time to design the pipe and joins such as brazing. The assembling work by technology had to rely on a skilled person. Therefore, there is a problem that automatic assembly by a machine is difficult and cost reduction is difficult by rationalizing production. Further, during operation of the air conditioner, there is a problem of reliability such that the refrigerant pipes arranged in the three-dimensional space may be broken by vibration, and it takes a lot of time to deal with them.

As one of the prior arts in consideration of such a point, there is a known example of a heat exchanger for refrigeration as shown in FIG. 13 (Japanese Utility Model Publication No. 50-142570). In FIG. 13, 9 is a refrigerant inflow pipe, 8 is a capillary tube which is one of pressure reducing mechanisms, 2 is a distributor, 5-1-1, 5-2-1, 5-1
2, 5-2-2 is a bend pipe, 7 is a header, 11 is an outlet pipe, 3 is a heat exchanger, 12 is a flow of air flowing into the heat exchanger 3, and 4 is an end plate of the heat exchanger. There is. Capillary tube 8, distributor 2, bend tube 5-1-1, 5-2
1, 5-1-2, 5-2-2, and the header 7 are formed in the end plate 4 in which two flat plates 4a and 4b are joined. With such a configuration, the shape of the refrigerant pipe arranged in the three-dimensional space, which is a problem of the conventional technique, is simplified. However, in this conventional example, the refrigerant decompressed by the capillary tube 8 is distributed to the two passages by the distributor 2, and the refrigerant passages located upstream of the air flow 12 are bent pipes 5-1-1, 5-. The coolant passage located downstream of the air flow 12 through the 2-1 and the header 7 passes through the bend pipes 5-1-2 and 5-2-2, and then flows into the header 7 through the inflow pipe 11. leak. In such a conventional example, the heat exchanger cannot be effectively used because there is no means for optimizing the refrigerant flow distribution to the plurality of passages with respect to the wind velocity distribution of the air flow 12, the arrangement of the heat transfer tubes, and the like. was there.

[0004]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention simplifies the piping structure around the heat exchanger of an air conditioner to enable cost reduction and heat exchange. We will make full use of the performance of the container to reduce power consumption.

[0005]

[Means for Solving the Problems] Piping around a heat exchanger of an air conditioner is formed inside two flat plates to simplify the piping structure for the purpose of rationalizing production and to divide the refrigerant formed inside the flat plates. The heat exchanger performance is improved by making the passage resistance of the pipe adjustable.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention is shown in FIGS. Similar to FIG. 11, FIG. 1 shows an example of a piping system around a cooling heat exchanger of an air conditioning refrigeration cycle. The end plate 4 of the heat exchanger is composed of two plates 4a and 4b as shown in FIG. 3, and one side of 4a has distribution pipes 2-1 and 2-2.
Grooves for forming 2-3, 2-4, grooves for forming bend pipes 5-1, 5-2, 5-3, 5-4 of the heat exchanger, grooves for forming the header 7 7a and the inlet 1a of the refrigerant distributor 1 are formed (these grooves indicate grooves that bulge in the front direction from the paper surface of FIG. 3). Also, 4
In b, a groove forming the refrigerant distributor 1, a hole for opening the end of the heat transfer tube, and a groove 7b forming the header 7 are formed (these grooves are deeper than the paper surface of FIG. 3). Shows a groove that bulges in the direction). These plates are shown in FIG.
As shown in FIG. 2, the section A is connected by a brazing material 13 by means such as brazing in a furnace, and these two plates are connected to the refrigerant passages 1,2-1,2-2,2-3,2. -4 is molded. Various materials such as copper, iron, stainless steel, aluminum, etc. can be considered as materials for the two plates.

The flow of the refrigerant in these integrated pipes is shown below. The liquid-state refrigerant flowing from the inlet pipe 9 into the expansion valve 8 is decompressed into a gas-liquid two-phase flow state, flows into the refrigerant distributor 1 from the inlet pipe 10 to the refrigerant distributor, and is cooled by the refrigerant distributor 1. The liquid is divided into four streams with the same proportion, and the distribution pipe 2-
It is guided to a plurality of refrigerant passages of a heat exchanger along 1,2-2,2-3,2-4. In the case of the heat exchanger shown in the embodiment of FIG. 1, the refrigerant passages are divided into four passages from the top of the drawing,
The distribution pipe 2-1 is a heat transfer pipe 6-1-1, 6-1-2, 6-1.
The refrigerant is introduced into the uppermost passage of the heat exchanger of FIG. That is, the refrigerant exiting the distribution pipe 2-1 flows through the heat transfer pipe 6-1-1, makes a U-turn at a bend pipe (not shown) at the end of the heat transfer pipe, and then flows through the next heat transfer pipe 6-1-2. . The bend pipe 5-1 makes a U-turn again, and the heat transfer pipe 6-1.
-3, bend tube (not shown) at end of heat transfer tube, 6-1-4
Through the header end 7-1 into the header 7 and out from the outflow pipe 11. In a heat exchanger having such a passage configuration, generally, the air flow 12 flowing into the heat exchanger is non-uniform on the front surface of the heat exchanger, and due to the influence of the blower characteristics and the air flow path resistance, for example, an arrow in FIG. In many cases, there is a vertical velocity distribution as shown in. In such a case, the distribution pipe 2
If the flow path resistances of -1, 2, 2, 2, 3 and 2-4 are the same, sufficient heat exchange is performed with a large air flow rate in the upper passage of the heat exchanger of FIG. 4, and the refrigerant is overheated. The gas flows out of the heat exchanger, but the refrigerant flowing through the passages in the lower part of the heat exchanger is in an insufficient heat exchange state with a small amount of air, so the unevaporated liquid refrigerant flows out in an unbalanced state. Occurs,
The performance of the heat exchanger cannot be exhibited as compared with the case where the flow rate is properly distributed. In order to deal with such a problem, it is necessary to properly set the resistance of the distribution pipe.

FIG. 5 shows an embodiment in consideration of such a case. Distribution pipe 2-1 on the plate 4a for processing the distribution pipe
2-2, 2-3, 2-4 cross-sectional area 2-1-S, 2-2-
S: 2-3-S, 2-4-S over the entire length 2: 2:
The setting is different from 1.5: 1. In order to change the flow path resistance of the distribution pipe, the length of the distribution pipe may of course be set differently. The flow path resistance is proportional to the first power of the length of the distributor pipe, and inversely proportional to the fifth power of the diameter when considering the cross-sectional area of the distribution pipe as a circle having an equivalent diameter, so changing the cross-sectional shape is longer. It is more effective to change the flow path resistance than to change it.

FIG. 6 shows another embodiment for setting the resistance of the distribution pipe. The symbols indicate the same contents as in FIG. The difference from FIG. 5 is that a passage 2-3 is formed by narrowing the cross section of a part of the distribution pipes 2-3 and 2-4 to increase the flow resistance.
1, 4-4-1. Also in this case, FIG.
The effect of controlling the flow rate of the refrigerant flowing through the plurality of passages of the heat exchanger is also provided.

FIG. 7 shows an embodiment in which the resistors 2-3-2 and 2-4-2 are inserted into a part of the distribution pipe processed to have the same sectional shape to change the flow path resistance of the distribution pipe. is there. In the figure, the orifices 2-3-2 and 2-4-2 are inserted in the middle of the refrigerant passage as shown by breaking some of the distribution pipes 2-3 and 2-4. A method of inserting a small-diameter tube such as a capillary tube instead of the orifice may be considered. Also in this case, as in FIGS. 5 and 6, the effect of controlling the flow rate of the refrigerant flowing through the plurality of passages of the heat exchanger is obtained.

FIGS. 8 and 9 show another embodiment of the present invention in consideration of application to a heat exchanger in which the arrangement of heat transfer tubes is different from that in FIG. Unlike the embodiment shown in FIG. 1, the bend pipes 5-1, 5-2, 5-3, 5-4 in FIG. 8 are not integrally molded with the plate 4a as shown in FIG. Has become. Holes 5-1 through which the heat transfer tubes 6-1-2 and 6-1-3 pass through the plate 4a.
1, 5-1-2 are provided. Similarly for other passages, heat transfer tubes 6-2-2, 6-2-3, 6-3-2, 6
Holes 5-2 through which 3-3-3, 6-4-2, 6-4-3 penetrate
-1,5-2-2,5-3-1,5-3-2,5-4-
1, 5-4-2 are provided. Bend pipes 5-1 and 5
-2, 5-3 and 5-4 are similar to the bend pipe of the prior art, and an integrated pipe is formed by two plates and then brazed later. With such a configuration, even when a heat exchanger having different refrigerant passage configurations is configured, it is not necessary to change the plate 4b on one side, only the other plate 4a needs to be changed, and integrated piping is applied. This has the advantage of cost reduction. For example, FIG. 10 shows an embodiment in which two refrigerant passages are formed using the same heat exchanger. In FIG. 10, symbols indicate the same contents as those in FIGS. 9 and 10.
The difference from FIG. 9 is that two distribution pipes 2-1 and 2-2 are processed on the plate 4a and the processing shape of the header 7a is different. The other plate 4b is the same as in the case of FIG. That is, in mass production, the same member 4b can be used in the case of configuring the four-passage heat exchanger integrated pipe in FIG. 9 and in the case of configuring the two-passage heat exchanger integrated pipe in FIG. There is an advantage that you can.

FIG. 11 is characterized in that the area of the end portion of the distribution pipe is increased in the above-described embodiment so that there is a margin in the alignment of the joint between the distributor and the heat transfer tube. In FIG. 11, distribution halls 2-1, 2-2, 2-3, 2-4 are circular end portions 2-1A, 2-having diameters larger than the passage widths of the distribution pipes, respectively.
B, 2-1A, 2-2B, 2-3A, 2-3B, 2-4
I have A, 2-4B. With such a shape, when the two plates 4a and 4b are joined to form an integrated pipe, for example, the distribution pipe 2-1 is the end portion 1-1 of the distributor 1.
Also, the alignment with the end portion 6-1-1 of the heat transfer tube becomes easy, and it is possible to produce integrated piping with little variation.

[0013]

EFFECTS OF THE INVENTION Since the refrigerant passages around the heat exchanger, which have been three-dimensionally shaped in the past, are integrated into a two-dimensional flat plate, automatic assembly by a machine is facilitated, and cost can be reduced by rationalizing production. Become. In addition, since the flow path resistances of a plurality of refrigerant distributor tubes in the integrated piping can be set differently, the performance of the heat exchanger can be maximized and there is an effect of contributing to power saving. . Further, of the two plates constituting the integrated pipe, one plate can be shared even if the shape of the heat transfer tube passage of the heat exchanger is changed, so that the cost can be further reduced by rationalizing the production. Further, since the connection state of the refrigerant passages of the integrated pipe can be stabilized, the reliability of the integrated pipe molding is increased and the cost reduction effect can be further expected.

[Brief description of drawings]

FIG. 1 is a perspective view of a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is an exploded perspective view of the embodiment shown in FIG.

FIG. 4 is a flow velocity distribution diagram of air flowing into the heat exchanger.

5 is a perspective view of the distributor tube of FIG. 1. FIG.

FIG. 6 is a perspective view of a second embodiment of the distributor tube.

FIG. 7 is a perspective view of a third embodiment of the distributor tube.

FIG. 8 is a perspective view of a second embodiment of the present invention.

9 is an exploded view of the embodiment of FIG.

FIG. 10 is another exploded view of the embodiment of FIG.

FIG. 11 is an exploded view of an embodiment of a distribution pipe that can be commonly applied to the above embodiments.

FIG. 12 is a perspective view of a conventional technique.

FIG. 13 is a perspective view of a conventional technique.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Refrigerant distributor, 2-1, 2-2, 2-3, 2-4 ... Distribution pipe, 3 ... Heat exchanger, 4 ... End plate of heat exchanger, 5-1 and 5
-2, 5-3, 5-4 ... Bend tube of heat exchanger, 7 ... Header, 7-1, 7-2, 7-3, 7-4 ... Header end portion, 8
... expansion valve, 9 ... expansion valve inlet pipe, 10 ... inflow pipe to refrigerant distributor, 11 ... outflow pipe from header, 12 ... flow of air flowing into heat exchanger.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yu Kunikata 390 Muramatsu, Shimizu-shi, Shizuoka Prefecture Air conditioning system division, Hitachi, Ltd. (72) Inventor Kingo Moriyama 4-6, Kanda Surugadai, Chiyoda-ku, Tokyo Hitachi (72) Inventor Minetoshi Izushi 390 Muramatsu, Shimizu-shi, Shizuoka Hitachi Air Conditioning Systems Division (72) Inventor Hideyuki Parki 292 Yoshida-cho, Totsuka-ku, Yokohama, Kanagawa Co., Ltd. In-house

Claims (1)

[Claims] 1. A refrigerant distributor for distributing a refrigerant flowing into a heat exchanger into two flat plates which are press-formed and bonded together, a distribution pipe for guiding the refrigerant from the refrigerant distributor to the heat exchanger, and the heat. An integrated pipe for a refrigeration cycle, characterized in that a part of the bend pipe of the exchanger and the header are integrally molded.