JPH054599B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a stacked heat exchanger for use as an evaporator in a refrigeration system or the like.

[Prior Art] A heat transfer medium has an inlet/outlet for a heat transfer medium, and has a structure in which a large number of flat tubes in the shape of a flat thin plate are laminated and combined so that each inlet/outlet is connected to each other.
The laminated heat exchanger in the art, which is mainly used as a refrigerant evaporator in refrigeration equipment, is the 14th layer heat exchanger.
It has a general structure as shown in FIG.

Fig. 14 is a front view of a heat exchanger as a refrigerant evaporator, Fig. 15 is a partially enlarged sectional view thereof, Fig. 16 shows how the refrigerant vapor pressure is applied, and Fig. 17 shows the refrigerant in the heat exchanger. It is a partial cross-sectional view explaining how the refrigerant flows, where A1, A2... are a group of thin plate-shaped flat tubes, and B1, B2... are holes for insertion of a refrigerant distribution pipe or a collecting pipe provided in the flat pipe A. The refrigerant inlet/outlet port is formed by expanding the peripheral part of the refrigerant, a is the fixation surface of the adjacent ports, b is the joining fixation point of the lower end of the adjacent flat tube A, and d is the two-part structure. This is the collision line of the flat tube A having the structure shown in FIG. 3 is a distribution pipe for distributing refrigerant to the flat tube group A, and 4 is a collecting pipe for collecting the distributed refrigerant again, which is located behind 3 in this figure. Reference numerals 5 and 6 denote refrigerant outlet or inlet holes provided in the refrigerant distribution pipe 3 so as to communicate with each of the port portions B group. The refrigerant distribution (collection) pipes 3 and 4 are assembled in such a manner that they pass through the insertion holes ef provided so as to pass through the port portions B of each of the plate-shaped flat tubes A group. 7 and 8 are piping for refrigerant circulation, and 9 is a corrugated fin installed between the flat tubes A group.

In the heat exchanger with this structure, the refrigerant supplied from the pipe 7 flows into the refrigerant distribution pipe 3 as indicated by the arrows in FIG. After that, it flows down inside the flat A, and when it reaches the lower end, it passes through a cut section with a partition wall that vertically divides the inside of the pipe into two sections, then turns upward and returns to the port section B, where it flows into the refrigerant collecting pipe 4. The refrigerant flows into the collecting pipe 4 from the refrigerant outlet hole 6 provided in the refrigerant. While passing through the flat tube A, the refrigerant absorbs the latent heat of vaporization from the outside air through the corrugated fins 9 to perform refrigeration work, and is sucked into the refrigerant compressor via the pipe 8 for recirculation. It is configured.

[Problems to be Solved by the Invention] In the conventional heat exchanger as described above, as shown in FIG. 15, the refrigerant distribution pipe 3 or collecting pipe 4 is
Insertion holes e or f provided in the flat groups A1, A2..., port portions B1, B2..., excluding both ends thereof
It is simply being rubbed through. Therefore, a gap g exists between the refrigerant distribution (collection) pipes 3, 4 and their insertion holes e or f provided in the port section B.

As mentioned above, the refrigerant discharged from the refrigerant distribution pipe 3 into the port B exerts vapor pressure on the inner wall surface of the port B due to vaporization, as shown by arrow A in FIG. Therefore, the port portion B will receive an expansion force, and as a result, firstly, the second
A force F is generated that peels off the bonded fixed surface d of the flat tube A having a split structure, and a second force G is generated that expands the diameter of the insertion hole e of the distribution pipe 3 and causes a crack at the mouth edge. do. For heat exchangers with this type of structure, where the span distance is long and it is difficult to provide reinforcing means in the middle, the only way to improve the pressure resistance is to increase the thickness of the metal plate material such as aluminum that makes up the flat span A. .

Furthermore, in this type of heat exchanger, the refrigerant flow path is such that the refrigerant flows from the 5 groups of refrigerant inlets provided in the refrigerant distribution pipe 3 through the respective port portions B into each of the flat pipes A1, A2, etc. Although the refrigerant distribution (collection) pipe and the flat pipe A Since there is a gap g between the insertion holes e and f,
It is not possible to secure an independent flow path for each such flat tube, and the refrigerant that has once flowed into the port of the flat tube A1 located on the upstream side of the distribution pipe 3 flows down into the tube. As shown by the arrow B, the refrigerant flows into the port of the flat tube A2 on the downstream side in a short-circuit manner, and the refrigerant distribution pipe 3 connects the ports B1 and B.
This resulted in the inconvenience that the function of equal distribution to...2 was impaired.

The present invention provides a heat exchanger that can sufficiently increase the pressure resistance of the port portion B of the flat tube A, so that the wall thickness of the flat tube material can be thin, and can sufficiently ensure the refrigerant distribution function by the refrigerant distribution pipe 3. The purpose is to provide equipment.

[Means for Solving the Problems] In order to achieve the above object, the heat exchanger of the present invention can be divided into two in the flat direction, and a distribution pipe or a collecting pipe for the heat transfer medium is inserted into the flat plane. A group of disk-shaped flat tubes each having a communication hole and bulging out the peripheral portion of the hole to form a port for the entry and exit of a heat transfer medium are laminated together, and the tubes are inserted into the group of insertion holes. In a laminated heat exchanger having a structure in which distribution pipes or overlapping pipes are assembled, a flange-like part is provided at the periphery of the insertion hole, and the flange-like part is fixed to the distribution pipe or collecting pipe. A new configuration was adopted.

[Function] The heat exchanger of the present invention having the above structure has the following features:
By providing a flange-like part on the periphery of the insertion hole of the heat transfer medium distribution (collection) pipe, the thickness of the heat transfer medium inlet/outlet port part, and therefore the port part, can be reduced by the length of this flange-like part. By reducing the volume of the port, the pressure resistance strength of the port portion against the pressure exerted by the heat transfer medium is increased.

Then, the flange-shaped part is used to distribute (collect) the heat transfer medium.
By fixing it to the outer peripheral surface of the tube, the pressure resistance is further improved significantly, and the function of the distribution pipe is prevented from being impaired due to the heat transfer medium flowing between the flat tube groups in a short-circuit manner.

[Example] The heat exchanger of the present invention will be specifically described below based on the accompanying drawings.

Figures 1 to 6 are structural explanatory diagrams of a heat exchanger according to the present invention as an evaporator for an automobile air conditioner. For example, a main body formed by laminating and combining a group of flat tubes A, which are laminated together in an extremely flat "middle skin" shape and have a refrigerant inlet/outlet port part B at the upper end;
A refrigerant distribution pipe is built in so as to pass through the laminated and combined port parts B, and distributes the refrigerant to each port part B, and collects and collects the refrigerant that has made a round in each flat tube A. The main components are a refrigerant collecting pipe 4, a refrigerant supply pipe 7 and a discharge pipe 8 connected to these pipes, and a corrugated fin 9 fitted into the bottom part of the adjacent flat pipe A to increase the heat transfer area. It is made up of elements. 15 is a side wall plate for reinforcement.

As shown in Figures 3 and 4, the flat tube A is made of an aluminum plate made of A3003 with a thickness of 0.4 mm to 0.8 mm, and has a brazing material of about 10% of the plate thickness on both surfaces.
Core plates 1 and 2, which have been previously clad with A4004 using a melt plating method, are each press-molded into an extremely flat “skin in the middle” and then bonded together using a brazing method. It is shaped in a twisted manner. Both core plates 1 and 2 are provided with outward bulging portions 1a and 2a at their upper ends, and the inner spaces of both bulging portions 1a and 2a function as a port portion B for the refrigerant to enter and exit the flat tube A. do. Further, both tank plates 1 and 2 are respectively provided with vertical partition walls 1b and 2b for dividing the interior space of the flat tube A into two compartments.
Due to the lack of the lower end of both compartments h
A communication path j between and i is formed. The distribution pipe 3 located above the compartment h is provided with a refrigerant supply slit 3a, and the collecting pipe 4 located above the compartment i is provided with a refrigerant discharge slit 4a.
The refrigerant flowing from the slit 3a flows down the compartment h, reaches its lower end, passes through the communication path j, and then
A refrigerant flow path is formed which turns upward and reaches the slit 4a. The core plates 1 and 2 are provided with a large number of ribs 1c and 2c, respectively, for dividing the refrigerant flow path and reinforcing the flat tube A. When assembled, the ribs 1c and 2c and the partition walls 1b and 2b of both plates are brought into contact and brazed together. Note that the ribs 1c and 2 are oriented in an inclined direction.
In c, by making the diagonal directions opposite to each other, both ribs abut against each other in an X-shaped crossing state, thereby increasing the structural strength of the flat tube A. 1
d and 2d are fin-like parts formed by bending the lower edges of the core plates 1 and 2 at right angles,
It functions as a connecting body member for the lower end edges of adjacent flat tubes A. 1 is a contact surface of the fin-like portions of adjacent flat tubes A, and d is a joint surface for brazing and joining the core plates 1 and 2, which covers the respective peripheral edges of the core plates 1 and 2.

Holes 10 and 11 for insertion of the refrigerant distribution pipe 3 and the refrigerant collecting pipe 4 are bored on both sides of the refrigerant inlet/outlet port part B of the flat tube A, respectively, and holes 10 and 11 for insertion of the refrigerant distribution pipe 3 and the refrigerant collecting pipe 4 are bored on the sides of the port part B at the periphery of each hole. Flange-like portions 12, 13 are formed which extend outwardly at right angles thereto.

The refrigerant distribution pipe 3 and the refrigerant collecting pipe 4 are flat pipes A
As shown in FIGS. 1 and 2, the flange-shaped portions are respectively provided in the port portions B group, penetrating the laminated combined layers of port portions B1, B2, etc. of port portions B1, B2, and so on. 12 and 13,
It is fixed by brazing. In the refrigerant distribution pipe 3 and the collecting pipe 4, a slit 3a for supplying refrigerant to each flat pipe A having a built-in independent refrigerant passage, and a slit 4a for discharging refrigerant are provided in port portions B1, B2, respectively. As shown in FIG. 5, they are provided at regular intervals so as to open toward the opposite direction.

In FIG. 6 illustrating the means for attaching the refrigerant supply pipe 7 or discharge pipe 8 to the evaporator, 2
0 is a metal joint member for attaching the refrigerant supply pipe 7 or the discharge pipe 8, and is a rectangular cylindrical main body portion 21
It is made by brazing plugs 22 and 23 at both open ends. This joint member 20 is provided with a hole 24 for fitting the refrigerant pipe 7 or 8 and a hole 25 for fitting the pipe end of the refrigerant distribution pipe 3 or the refrigerant collecting pipe 4. 7a is the fitting hole 2 for the outer diameter of the tube end.
This is a drawing part to match the diameter of No. 4.
The joint member 20 and the refrigerant pipe 7 or 8 and the refrigerant distribution pipe 3 or the refrigerant collecting pipe 4 are airtightly joined together by brazing.

The method of assembling an evaporator with the above structure is no different from that of conventional methods, and consists of core plates 1 and 2, which are clad with brazing filler metal in advance.
The refrigerant distribution pipe 3, the collector pipe 4, and the corrugated fin 9 in which the brazing material is not clad are temporarily assembled in the state shown in Figs. 1 and 2, fixed with a jig, and then Assembly is completed by passing it through.

FIG. 7 is an external perspective view of the evaporator, and FIG. 8 is a diagram schematically explaining a refrigerant flow path inside the evaporator, and 27 and 28 are piping joints. k is a streamline showing how the refrigerant flows within each flat tube A.

Next, the operational characteristics of the heat exchanger according to the present invention will be described in FIG. 9, which is a partial longitudinal sectional view, and FIG.
This will be explained with reference to FIG. The liquid phase refrigerant sent into the refrigerant distribution pipe 3 from the refrigerant supply pipe 7 is passed through refrigerant supply slits 3a provided at regular intervals in the distribution pipe 3 to the refrigerant inlet/outlet port B of each flat tube A. As the gas is discharged and vaporization and expansion begins by absorbing outside air heat, vapor pressure is exerted on the inner wall surface of port B as shown by the arrow in the figure, and as mentioned above, the two-part structure is formed. A force F trying to peel off the brazed joint surface d of the flat No. A having
An acting force G is generated that expands the diameters of the insertion holes 10 and 11 of the refrigerant distribution pipe and collecting pipe on both sides of the port portion B, and causes cracks to occur at the mouth edges. However, as is clear from FIG. 16, which is a partial sectional view of a heat exchanger with a conventional structure, the port portion B has flange-like portions 12 and 13 on both sides thereof.
Since the thickness (width in the flat direction) of the port portion B is reduced by the amount that is provided, the internal volume of the port is reduced to a considerable extent, and the degree to which the port portion B is deformed by internal pressure is significantly reduced. Therefore, the peeling force exerted on the bonding surface d is significantly reduced. In this example, the thickness of the port portion B including the flange portion was set to 13.6 mm, and the lengths of the flange portions 12 and 13 were each set to 3.0 mm. Since the flange-shaped parts 12 and 13 are tightly fitted to the refrigerant distribution pipe 3 and fixed by brazing, the degree to which the port part B is expanded and deformed by internal pressure is further significantly reduced. Because the port part B and the refrigerant distribution pipe 3 or the collecting pipe 4 are firmly joined together by brazing,
Adjacent flat tubes A that existed in conventional evaporators
Since the gap g that spatially short-circuits the respective port portions B is eliminated, another drawback of the conventional structure of the evaporator, that is, the distribution function of the refrigerant distribution pipe 3 is degraded due to the gap g, is also solved.

10 to 12 show examples of other shapes of the flange-like portions provided on both sides of the port portion B of the flat tube A. Flange-shaped portion 30 in FIG.
and 31 are provided with folded parts 30a and 31a facing toward the outer circumferential side on their tip surfaces, so that
It is possible to increase the resistance force with which the flange-shaped portion is able to withstand expansion of its diameter due to the internal pressure of the port portion B, and also contributes to improving the structural strength of the evaporator.

Flanges 32 and 3 shown in FIG.
3 is constructed so that the flange-shaped parts provided at each port part of adjacent flat tubes A are brazed to each other while overlapping each other, so that the same effect as in the previous embodiment can be obtained. can get.

Flanges 34 and 3 of the embodiment of FIG.
5, the bulge portion for overlapping the flange portions provided on the flange portion 32 shown in FIG. 11 is omitted.

Further, in the embodiment shown in FIG. 13, the flat tube A
In order to extremely reduce the internal volume of the port portion B and increase the pressure resistance, both flange-like portions 36 and 3
The port portion is shaped such that the joining and fixing surfaces d of each half of the ports No. 7 are connected with a straight line.

In this embodiment, as shown in FIG. 8, the refrigerant flows all at once in a U-shape from the cooling distribution pipe 3 to the refrigerant collecting pipe 4 along the refrigerant passages in each flat tube A. By providing a partition plate to block the flow of refrigerant in the refrigerant distribution pipe 3 and, if necessary, in the refrigerant collecting pipe 4, the number of refrigerant passages through which refrigerant flows at once can be reduced, and the amount of refrigerant distributed in each refrigerant passage can be reduced. It is clear that the refrigerant may be made to flow more uniformly from the refrigerant distribution pipe 3 to the refrigerant collecting pipe 4, then back to the refrigerant distribution pipe 3, and then again to the refrigerant collecting pipe 4, and so on.

[Effects of the Invention] The heat exchanger according to the present invention has the following effects.

(b) By providing a flange-like part on the edge of the insertion hole of the refrigerant distribution (collecting) pipe on both sides of the port part of each flat tube, only the part where the thickness of the port part is reduced becomes a port. The internal volume is reduced, and the pressure resistance of the port against refrigerant vapor pressure is significantly improved. Since the width of the gap between adjacent flat tubes remains unchanged, the surface area of the corrugated fin also remains unchanged.

(b) Due to the effect of (a) above, the wall thickness of the core plate constituting the flat tube can be reduced, leading to reductions in material costs and weight.

(c) Refrigerant distribution (collection) using the flange-shaped part of the port
Since the tube is airtightly brazed and the two are fixed together, the structural strength (deformation resistance) of the port section can be further dramatically improved.

(d) By taking the measures in (c) above, the gap between the insertion holes of the refrigerant distribution (collecting) pipes on both sides of the port section and the insertion piping, as seen in conventional heat exchangers. Since there is no gap between the ports, there is no short-circuit refrigerant flow between adjacent port sections, and the refrigerant can be evenly distributed to each port section, improving heat exchange performance.

[Brief explanation of drawings]

1 to 13 are views showing an embodiment of the heat exchanger according to the present invention, in which FIG. 1 is a front view, FIG. 2 is a partially enlarged vertical sectional view of FIG. 1, and FIGS. 3 and 4. 5 is a side sectional view and a plan view of one of the two tank plates that make up the flat tube, FIG. 5 is a side view and cross sectional view of the refrigerant distribution (collection) pipe, and FIG. FIG. 7 is an external perspective view of the heat exchanger, FIG. 8 is a schematic diagram showing the refrigerant flow path inside the heat exchanger, and FIG. 9 is a perspective view explaining how to install the refrigerant piping. 10 to 12 are longitudinal cross-sectional views of the vicinity of the port section illustrating different shapes of the flange-shaped portion formed in the port section, and FIG. FIG. 13 is a longitudinal sectional view near the port section showing another example of the shape of the port section, and FIGS. 14 to 17 are drawings regarding an evaporator as a conventional heat exchanger,
Fig. 14 is a front view, Fig. 15 is a partial enlarged vertical sectional view of Fig. 14, Fig. 16 is an explanatory diagram of the situation in which refrigerant vapor pressure is applied to the port, and Fig. 17 is from the refrigerant distribution pipe to each flat pipe. FIG. 2 is an explanatory diagram showing a situation in which refrigerant flows into a port portion of the vehicle. In the diagram, A...Flat tube, B...Port section, 1, 2
... core plate, 3 ... refrigerant distribution pipe, 4 ... refrigerant collecting pipe, 3a, 4a ... refrigerant inlet/outlet slit,
12, 13...flange-shaped portion, d...bonding joint surface of flat tube.

Claims (1)

[Scope of Claims] 1. It can be divided into two parts in the flat direction, and a hole for the insertion of a distribution pipe or a collecting pipe for the heat transfer medium is provided in the flat plane, and the periphery of the hole is bulged to allow the heat transfer medium to pass through. In a laminated heat exchanger having a structure in which a group of plate-shaped flat tubes each forming an inlet/outlet port portion are laminated and combined, and the distribution tube or superimposed tube is assembled so as to be inserted into the insertion hole group, A heat exchanger characterized in that a flange-like part is provided at the periphery of the insertion hole, and the flange-like part is fixed to the distribution pipe or the collecting pipe.