JPH0412375Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a stacked heat exchanger formed by stacking a plurality of tubes each having a pair of molded plates joined together.
For example, a laminated heat exchanger suitable for use in a refrigerant evaporator or refrigerant condenser incorporated in the refrigeration cycle of an air conditioner, a hot water heater incorporated in a heating device, or a radiator incorporated in the cooling water path of an internal combustion engine. Concerned with vessels.

[Prior Art] Conventionally, as shown in FIGS. 13 to 18, the heat exchange unit 501 of the laminated heat exchanger 500 includes a shallow dish-shaped portion 511 and a shallow dish-shaped portion 511.
Two molded plates 510 each having a bulge 512 formed at the end of the U are joined together to form a U through which the refrigerant passes.
A letter-shaped refrigerant passage 521 and the refrigerant passage 521
A flat tube 5 with a tank 522 at the end of
20 is formed, and corrugated fins 530 are further arranged on both sides of the tube 520, and a plurality of these are laminated.

A side plate 550 (FIGS. 13 to 15) is attached to the bulging portion 542 formed at the end of the flat portion 541 of the outermost molded plate 540 disposed at the outermost side of the heat exchange unit 501.
Alternatively, the ends of the inlet/outlet pipe 560 (FIGS. 16 and 18) are joined.

This type of laminated heat exchanger 500 is manufactured by sandwiching the heat exchange unit 501, side plate 550, and inlet/outlet pipe 560 between assembly jigs (not shown) and brazing them together in a furnace.

[Problem to be solved by the invention] However, the conventional laminated heat exchanger 5 having the above configuration
In 00, if the contact area between the joint surface 551 between the outermost molded plate 540 and the side plate 550 or the joint surface 561 between the outermost molded plate 540 and the inlet/outlet pipe 560 is large, the gas in the brazing filler metal that cannot escape will cause the joint between the two. There is a risk that problems may occur, such as when the brazing filler metal remains in the joint or the brazing filler metal near the center of the joint does not melt. In these cases, small gaps (cavities) may occur in the joint, which may reduce the brazing properties of the joint.

Outermost molded plate 540 and side plate 5
If the laminated heat exchanger 500 with cavities still formed on the joint surface 551 of the molded plate 50 or the joint surface 561 of the outermost molded plate 540 and the inlet/outlet pipe 560 is used as a refrigerant evaporator in a cooling device, the cavities will be removed. Condensed water adhering to the refrigerant evaporator enters the refrigerant evaporator, and as the refrigerant evaporator operates, the condensed water repeatedly freezes, expands, and thaws due to thermal cycles, gradually expanding the cavity.

Finally, the outermost molded plate 540, the side plate 550, or the inlet/outlet pipe 560
A crack (so-called freeze crack) occurs in the refrigerant passage 5.
There was a problem that the refrigerant in the tank 21 or the tank 522 leaked to the outside.

The present invention aims to provide a laminated heat exchanger that prevents the occurrence of cavities and improves the brazing performance between the outermost molded plate and the joining member.

[Means for Solving the Problems] The laminated heat exchanger of the present invention has two molded plates each consisting of a shallow dish-shaped part and a bulge formed at the end of the dish-shaped part, which are joined together. A heat exchange unit comprising a fluid passage through which a fluid passes, and a plurality of laminated flat tubes forming links at the ends of the fluid passage, and an outermost molded plate disposed at the outermost side of the heat exchange unit. In a laminated heat exchanger comprising a joining member joined to the bulging part by brazing, the bulging part of the outermost molded plate to which the joining member is brazed has a gap between it and the joining member. A structure was adopted in which a recess was provided to form a passage.

[Function] The stacked heat exchanger of the present invention has the following function due to the above structure.

By providing a recess that forms a passage between the bulge of the outermost molded plate and the joint member to which the joint member is brazed, the bulge of the outermost molded plate and the joint member can be bonded together. By reducing the contact area of the molded plate, it is possible to prevent the formation of cavities and improve the brazing performance between the bulging portion of the outermost molded plate and the joining member.

Further, even if foreign matter such as water enters the recess, the recess forms a passage with the joining member, so that the foreign material such as water flows out from the recess.

[Effects of the Invention] The laminated heat exchanger of the present invention has the following effects due to the above configuration and operation.

The generation of cavities can be prevented, and the brazing performance between the bulging portion of the outermost molded plate and the joining member can be improved. Further, since foreign matter such as water flows out through the recess, it is possible to prevent foreign matter from accumulating between the bulge portion of the outermost molded plate and the joining member.

[Example] The laminated heat exchanger of the present invention is shown in Figs. 1 to 13.
Description will be made based on the embodiment shown in the figures.

FIGS. 1 to 7 show a single-tank stacked refrigerant evaporator incorporated in a refrigeration cycle of an automobile cooling system, which employs a first embodiment of the present invention.

Figures 1 to 3 show the outermost molded plate of the refrigerant evaporator, Figure 4 shows the refrigerant evaporator, Figures 5 and 6 show the main parts of the refrigerant evaporator, and Figure 7 shows the refrigerant evaporator. The inlet pipe is shown.

1 indicates a refrigerant evaporator. The refrigerant evaporator 1 is manufactured by joining side plates 12 to both sides of a heat exchange unit 11, sandwiching the side plates 12 using an assembly jig (not shown), and brazing them together in a furnace. The side plate 12 protects the outermost corrugated fin 13 disposed on the outermost side of the heat exchange unit 11 and prevents the brazing material (aluminum brazing material in this embodiment) from adhering to the assembly jig.

The heat exchange unit 11 is composed of a flat tube 2 and corrugated fins 14 arranged on both sides of the tube 2.

The tube 2 is made up of two molded plates 3 that are formed by pressing a thin brazing sheet into a predetermined shape, the surface of a thin aluminum alloy plate being coated with aluminum solder.
It is formed by heating and melting aluminum solder by brazing the aluminum solder with the aluminum solder facing each other.

The molded plate 3 includes a shallow dish-shaped part 31 formed from the upper end to the lower end, and a first bulge part 3 in which the upper end of the dish-shaped part 31 bulges outward.
2 and a second bulge 33 are formed.

The tube 2 has a U-shaped refrigerant passage 21 through which the refrigerant passes, by joining the dish-shaped portion 31 and the two bulging portions 32 and 33 of the two molded plates 3 to face each other. The refrigerant passage 21 has egg-shaped inlet/outlet tank parts 22 and 23 provided at the upper end thereof, and an egg-shaped intermediate tank part 24.

Further, the upper end portion of the outermost molded plate 4 disposed at the outermost side of the heat exchange unit 11 is joined to the inlet/outlet pipes 5 and 6, which are joining members.

The outermost molded plate 4 includes a flat part 41 formed from the upper end to the lower end, and a first bulging part 4 in which the upper end of the flat part 41 bulges outward.
2 and the second bulging portion 43 are integrally molded by press working, and constitute the tube 2 together with the opposed molded plate 3.

The flat portion 41 forms a refrigerant passage 21 together with the opposing dish-shaped portion 31 of the molded plate 3 . The first bulging portion 42 has a nozzle 44 protruding into the inlet/outlet pipes 5, 6, and together with the first bulging portion 32 of the opposed molded plate 3, the inlet/outlet tank portion 22,
form 23.

The second bulge 43 is formed by the opposing molded plate 3
The intermediate tank portion 24 is formed together with the second bulging portion 33 . The second bulging portion 43 includes a first rib 45 having a substantially elliptical shape raised in the direction of the inlet/outlet pipes 5 and 6, and a substantially rectangular recess surrounded by the first rib 45. 46, and two arc-shaped second ribs 47 that are projected from the top surface 45a of the first rib 45 in the direction of the inlet/outlet pipes 5 and 6.

The first ribs 45 are provided at opposing positions,
Two approximately semicircular portions 45 with second ribs 47 protruding from them
b, and two connecting portions 45c provided facing each other in the vertical direction so as to connect these approximately semicircular portions 45b. The connecting portion 45c of the first rib 45 and the recess 46 form a passage 48 between the inlet and outlet pipes 5 and 6. Moreover, this first rib 45 is formed at the same position as the raised part 34 of the second bulging part 33 of the molded plate 3.

The recess 46 has an end surface 46a formed on the same plane as the outer surface 41a of the flat portion 41.

The top surface of the second rib 47 is
It is used as a joint surface 49 with the inlet and outlet pipes 5 and 6. This joint surface 49
is formed into a flat surface with a width of 2 mm to 3 mm, so
No nest is formed.

The inlet/outlet pipes 5, 6 are made of thin-walled aluminum alloy tubes that are formed into a predetermined shape by press working.

The inlet/outlet pipe 5 is connected to a refrigerant pipe 51,
A refrigerant passage 52 is formed inside. This inlet/outlet pipe 5 has a communication hole 54 that communicates with the inlet/outlet tank section 22 formed in a side wall 53 of the heat exchange unit 11 . A nozzle 44 formed in the first bulge 41 of the outermost molded plate 4 is inserted into the communication hole 54 .

Further, the inlet/outlet pipe 5 is connected to the heat exchange unit 11
A first joint portion 55 that joins to the first bulging portion 42 of the outermost molded plate 4 is provided on the side surface 53a. Further, the inlet/outlet pipe 5 is attached to the second side of the outermost molded plate 4 on the side surface 53a of the heat exchange unit 11.
A second joint portion 56 is provided which joins to the joint surface 49 of the second rib 47 of the bulging portion 43 .

The inlet/outlet pipe 6 has almost the same configuration as the inlet/outlet pipe 5, and only the different parts from the inlet/outlet pipe 5 will be explained. The inlet/outlet pipe 6 is a refrigerant pipe 61
is connected to.

A method of manufacturing the refrigerant evaporator 1 of this embodiment will be explained based on the drawings.

By pressing the brazing sheet, the dish-shaped part 31 and the first bulge part 32 and the second bulge part 3 formed at the upper end of the dish-shaped part 31 are formed.
A molded plate 3 having 3 is formed.

Two of these molded plates 3 are joined to form a flat tube 2 having a refrigerant passage 21 through which the refrigerant passes, and an inlet/outlet tank part 22, 23 and an intermediate tank part 24 at the upper end of the refrigerant passage 21. Corrugated fins 1 are placed on both sides of this tube 2.
4, and a plurality of tubes 2 and corrugated fins 14 are stacked to form the heat exchange unit 11.

Here, in the case of the outermost molded plate 300 (comparative example) as shown in FIG. If only 320 is stamped out, the joint between the molded plate and the outermost molded plate will be at an acute angle, stress will be concentrated, and the fatigue strength will be significantly reduced.

The second bulge 43 of the outermost molded plate 4 of this embodiment is located at the same position 40 as the upright portion 34 of the second bulge 33 of the molded plate 3 during press working.
The first rib 45 stands up in the direction of the inlet/outlet pipe 5.
is formed, and a second bulge 43 is formed in the inlet/outlet pipe 5.
A recess 46 is formed so that the first
A second rib 47 is formed further upright from the rib 45 in the direction of the inlet/outlet pipe 5. Therefore, the joint between the molded plate 3 and the outermost molded plate 4 does not form an acute angle, preventing a decrease in fatigue strength due to concentration of stress, and improving the pressure resistance of the heat exchange unit 11.

The first bulge 42 and the second bulge 4 of the outermost molded plate 4 of the heat exchange unit 11
3, the inlet/outlet pipes 5 and 6 are joined to the outermost corrugated fin 13, and the side plate 12 is joined to the outermost corrugated fin 13.
The refrigerant evaporator 1 is manufactured by sandwiching the side plates 12 using assembly jigs and brazing them together in a furnace.

Here, in this embodiment, the outermost molded plate 4
The second rib 4 from the outer surface 41a of the flat part 41 of
Since the height to the joint surface of 7 is the same as the height of the bulging part of the conventional outermost molded plate, the inlet/outlet pipes 5 and 6 can be held down with the same assembly jig as the conventional one. There is no need to create a new assembly jig specifically for the refrigerant evaporator 1.

At this time, the first bulging part 42 of the outermost molded plate 4 of the heat exchange unit 11 and the first joint part 55 of the inlet/outlet pipe 5 are joined, and the heat exchange unit 1
The second bulging portion 43 of the outermost molded plate 4 and the second joint portion 56 of the inlet/outlet pipe 5 are joined.

In particular, the second joint 56 of the inlet/outlet pipe 5
is joined in line contact (with a width of 2 mm to 3 mm) to the joining surface 49 of the second rib 47 that is formed on the second bulging portion 43 of the outermost molded plate 4 during press working, and
Further, a passage 48 is formed between the connecting portion 45c of the first rib 45 and the recess 46 and the inlet/outlet pipes 5, 6.

Therefore, the contact area between the second bulging portion 43 of the outermost molded plate 4 and the second joint portion 56 of the inlet/outlet pipe 5 is significantly smaller than that of the conventional laminated heat exchanger 500, and In this way, problems such as gas in the aluminum solder that cannot escape remaining in the joint between the two, or aluminum solder existing near the center of the joint not being melted in the furnace, can be prevented.

Therefore, in the refrigerant evaporator 1 of this embodiment, it is possible to prevent the formation of cavities between the second bulging part 43 of the outermost molded plate 4 and the second joint part 56 of the inlet/outlet pipe 5, and The brazing properties of the parts can be improved.

The operation of the refrigerant evaporator 1 of this embodiment will be explained based on the drawings.

Expansion valve installed in the refrigeration cycle (not shown)
The refrigerant that has flowed out passes through the refrigerant pipe 51 (or refrigerant pipe 61) and flows into the inlet/outlet pipe 5 (or the inlet/outlet pipe 6). The refrigerant that has flowed into the inlet/outlet pipe 5 (or the inlet/outlet pipe 6) flows through the communication hole 5
4 to each inlet/outlet tank section 22 (or inlet/outlet tank section 23), and flows into each refrigerant passage 21. The refrigerant that has passed through each refrigerant passage 21 is collected in the intermediate tank section 24 and distributed again to each refrigerant passage 21 in the intermediate tank section 24 . Furthermore, the refrigerant is
Each inlet/outlet tank part 23 (or inlet/outlet tank part 2
2), the inlet/outlet pipe 6 (or inlet/outlet pipe 5), the refrigerant pipe 51 (or the refrigerant pipe 61)
The refrigerant is then sucked into a refrigerant compressor (not shown).

Here, when the refrigerant passes through each refrigerant passage 21, it exchanges heat with warm air and evaporates. At this time, when the warm air passes through the heat exchange unit 11 and is cooled to below the dew point temperature, moisture in the air condenses and condensed water adheres to the entire heat exchange unit 11.

In particular, the condensed water adhering to the upper part between the second swollen part 43 of the outermost molded plate 4 and the side surface 53a of the heat exchange unit 11 of the inlet/outlet pipe 5 is caused by gravity to flow into the passage 48 (the connection of the first rib 45). 45c and between the recess 46 and the heat exchange unit side surface 53a of the inlet/outlet pipe 6), and is sent downward.

Further, in this embodiment, as described above, the joint surface 49 of the second rib 47 of the second bulging portion 43 of the outermost molded plate 4 and the second side surface 53a of the heat exchange unit 11 of the inlet/outlet pipe 5 Since no cavities are generated in the aluminum solder existing between the aluminum solder and the joint 54, problems such as accumulation of condensed water or leakage of the refrigerant in the refrigerant passage 21 to the outside due to freeze cracking can be prevented.

8 to 10 show a refrigerant evaporator employing a second embodiment of the present invention.

(The same functional parts as in the first embodiment are given the same numbers.) The refrigerant evaporator 10 of this embodiment has a joining member attached to the upper end of the outermost molded plate 7 disposed at the outermost side of the heat exchange unit 11. side plate 8
The upper ends of the two are joined. In addition, the refrigerant evaporator 10
Inlet/outlet pipes 16, 17 are arranged near the center of the heat exchange unit 11 to connect to an expansion valve housing 15 housing an expansion valve (not shown).

The outermost molded plate 7 is formed thicker than the molded plate 3 and the side plate 8 because it receives a large amount of internal pressure. This outermost molded plate 7 includes a flat part 71 formed from the upper end to the lower end, and a first bulging part 72 and a second bulging part 72 which bulge the upper end of the flat part 71 outward. The projecting portion 73 is integrally molded by press working, and constitutes the tube 2 together with the opposed molded plate 3.

The first bulging part 72 and the second bulging part 73 include four raised parts 75 that are partially raised in the direction of the side plate 8, and are surrounded by the raised parts 75, and the side plate Passage 76 between 8 and 8
Recesses 77 are respectively formed.
The top surface of the rising portion 75 is in line contact with the side plate 8 and also has a joint surface 78 with the side plate 8.
used as.

The side plate 8 has a first bulge 72 of the outermost molded plate 7 on the side surface 81 of the heat exchange unit 11.
A first joint portion 82 is provided which is joined to the joint surface 78 of the raised portion 75 of the second bulge portion 73 of the outermost molded plate 7.
is provided.

2. Description of the Related Art Conventionally, there have been refrigerant evaporators in which ribs are formed at joints of side plates in order to prevent accumulation of condensed water. However, if the thickness of the side plate is thin, the side plate will buckle during brazing, and the ribs will interfere with the inlet/outlet tank parts 22 and 23 and the intermediate tank part 2, which are important for pressure resistance of the heat exchange unit 11.
This was the cause of the weakening of the holding force in step 4.

However, when the recess 77 is provided in the upright portion 75 as in this embodiment, the side plate with ribs is not required, and there is no possibility that the side plate 8 will buckle. Moreover, the refrigerant evaporator 1 of this embodiment
0 has a rib effect due to the raised portion 75 of the outermost molded plate 7, which is thicker than the side plate 8, so the pressure resistance strength is higher than that of a conventional refrigerant evaporator heat exchange unit. Significantly improved.

Furthermore, in the refrigerant evaporator 10 of this embodiment, the side plate 8 has almost no effect on the pressure resistance, and is only used to protect the outermost corrugated fin 13 of the heat exchange unit 11 and to prevent the brazing filler metal from adhering to the assembly jig. The side plates of conventional refrigerant evaporators can be made significantly thinner.

Other functions and effects are the same as those in the first embodiment, so their explanations will be omitted.

FIG. 11 shows the outermost molded plate of a refrigerant evaporator employing a third embodiment of the present invention.

The second bulging portion 110 of the outermost molded plate 100 of this embodiment includes a substantially elliptical first rib 120,
An oval-shaped recess 130 and second ribs 140 provided at two locations on the first rib 120 are formed. The two second ribs 140 are arranged one above the other with the recess 130 in between, and form a joint surface 141 on the top surface to which a joint member such as an inlet pipe, an outlet pipe, or a side plate is joined.

FIG. 12 shows the outermost molded plate of a refrigerant evaporator employing a fourth embodiment of the present invention.

The second bulging portion 210 of the outermost molded plate 200 of this embodiment includes a first rib 220 having a substantially oval shape,
Approximately concave-shaped recess 230 and first rib 22
0 is formed with second ribs 240 provided at three locations. The second rib 240 forms a joint surface 241 on the top surface to which a joint member such as an inlet pipe, an outlet pipe, or a side plate is joined.

[Other Examples] In this example, the laminated heat exchanger of the present invention was adopted in a single tank type laminated refrigerant evaporator.
The stacked heat exchanger of the present invention may be used in double tank refrigerant evaporators, oil coolers, intercoolers, refrigerant condensers incorporated in the refrigeration cycle of air conditioners, and hot water heaters incorporated in heating devices. Alternatively, the present invention may be employed in a radiator or the like incorporated in a cooling water path of an internal combustion engine.

In this embodiment, the outermost molded plate according to the present invention is employed as both outermost molded plates of the heat exchange unit, but the outermost molded plate according to the present invention may be employed as one of the outermost molded plates.

In this embodiment, hard brazing is employed as the brazing method for the laminated heat exchanger, but soft brazing may be employed as the brazing method for the laminated heat exchanger.

In this embodiment, corrugated fins are used for the heat exchange unit, but plate fins may also be used for the heat exchange unit.

Furthermore, the shape and molding method of the recess that forms the passage with the joining member can be varied without departing from the scope of the present invention.

In the present invention, the shallow dish-shaped portion of the molded plate also includes a flat portion. Further, in this case, the other molded plate always has a groove so that the two molded plates can be joined to form a fluid passage.

[Brief explanation of the drawing]

FIG. 1 is a side view showing a part of the outermost molded plate of the refrigerant evaporator adopted in the first embodiment of the present invention, FIG. 2 is a sectional view taken along line A-A in FIG. 1, and FIG. 1 is a sectional view taken along line B-B in Fig. 1, Fig. 4 is a front view showing the refrigerant evaporator adopted in the first embodiment of the present invention, and Fig. 5 is a refrigerant evaporator adopted in the first embodiment of the present invention. FIG. 6 is a sectional view taken along line C-C in FIG. FIG. FIG. 8 is a plan view showing a refrigerant evaporator adopted in the second embodiment of the present invention, FIG. 9 is a sectional view showing a part of the refrigerant evaporator adopted in the second embodiment of the present invention, and FIG. FIG. 10 is a side view showing the joint portion of the side plates of the refrigerant evaporator adopted in the second embodiment of the present invention. Figure 11 shows the third part of this invention.
FIG. 12 is a side view showing a part of the outermost molded plate of the refrigerant evaporator adopted in the embodiment; FIG. 12 shows a part of the outermost molded plate of the refrigerant evaporator adopted in the fourth embodiment of the present invention; FIG. FIG. 13 is a front view showing a part of a conventional refrigerant evaporator, FIG. 14 is a sectional view showing a part of a conventional stacked heat exchanger, and FIG.
FIG. 5 is a side view showing the joints of the side plates of a conventional laminated heat exchanger, FIG. 16 is a sectional view showing a part of the conventional laminated heat exchanger, and FIG. D sectional view, FIG. 18 is a side view showing the side surface of the heat exchange unit of the inlet and outlet pipes of a conventional laminated heat exchanger, and FIG. 19 shows the joint of the outermost molded plate of a laminated heat exchanger of a comparative example. FIG. In the figure, 1... Refrigerant evaporator (stacked heat exchanger),
2...Tube, 3...Molded plate, 4,7,
100,200...Outermost molded plate, 5,6
...Inlet/outlet pipe (joining member), 11... Heat exchange unit, 21... Refrigerant passage (fluid passage), 22,
23... Entrance/exit tank part, 24... Intermediate tank part, 31, 41... Dish-shaped part, 32, 42, 72...
...first bulge, 33, 43, 73, 110, 2
10... second bulge part, 41, 71... plane part,
45,120,220...first rib, 46,1
30,230...dent, 47,140,240...
...Second rib, 48...Passway, 49,141,2
41...Joint surface.

Claims (1)

[Claims for Utility Model Registration] 1. Two molded plates each consisting of a shallow dish-shaped part and a bulge formed at the end of the dish-shaped part are joined to form a fluid passage through which a fluid passes, and the fluid A heat exchange unit formed by laminating a plurality of flat tubes each having a tank formed at the end of a passage; and a heat exchange unit that is joined by brazing to the bulge of an outermost molded plate disposed at the outermost side of the heat exchange unit. In the laminated heat exchanger comprising a joining member, the bulging portion of the outermost molded plate to which the joining member is brazed is provided with a recess that forms a passage between the joining member and the joining member. A laminated heat exchanger characterized by: 2. The laminated heat exchanger according to claim 1, wherein the joining member is a side plate, an inlet pipe, or an outlet pipe.