JPH07104076B2 - Evaporator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vaporizer for a refrigeration system of a type in which a hox-type expansion valve is installed by being installed between a refrigerant inlet and outlet pipes. Regarding the container (evaporator).

[Prior Art] FIGS. 7 to 9 show an example of the structure of a conventional evaporator. FIG. 7 is an external view, and FIGS. 8 and 9 are plan views of a tube plate forming a flat tube as a component of the evaporator.
It is a sectional side view of a flat tube.

The flat tube A is produced by bonding two shallow tray-shaped tube plates 1 as shown in the drawing, which are formed by pressing an aluminum plate, by a brazing method. At the upper end of the tube plate 1, an inlet tank portion 1A serving as a refrigerant inlet port and an outlet tank portion 1B serving as an outlet port portion are provided, and a jetty-like partition wall 1E is provided at the central portion so that the flat surface is formed. In the pipe A, a U-turn-shaped coolant flow path C connecting these tank parts is formed.

When a plurality of flat tubes A having such a structure are combined in a laminated manner by a brazing method as shown in FIG. 7, an inlet hole formed in the refrigerant inlet port 1A of each flat tube A
1C is electrically connected to each other to form a refrigerant distribution path E, and outlet holes 1D formed in the refrigerant outlet port 1B are also electrically connected to each other to form a refrigerant collecting path F. (See FIGS. 8 and 9). 1F
Is a group of ribs for reinforcing the flat tube A and forming a maze.

At a suitable location of each of the refrigerant distribution path E and the collecting path F, a specific flat pipe A2 or A3 is provided based on a positional relationship in which the refrigerant inlet pipe 2 and the refrigerant inlet pipe 3 are adjacent and parallel to each other.
It is built into one.

Since a heat exchange space B corresponding to the thickness of the tank portion is formed between the adjacent flat tubes A, the corrugated fins 15 are inserted in the space.

The assembling method of the evaporator having the above structure is such that the brazing material is clad on both surfaces of the tube plate 1 in advance, and the corrugated fins 15 and the plate-like joint member 5 are also stacked in the state shown in FIG. The heat exchange unit 100 is temporarily assembled by fitting or fitting. This state is fastened and fixed using a jig and then heated in a brazing furnace, whereby the main assembly is completed extremely efficiently.

[Problems to be Solved by the Invention] Refrigerant inlet pipes 2 and 3 of the evaporator having the above structure
As a method of connecting an expansion valve called a box type, for example, as illustrated in FIG.
The following method using the plate-like joint member 5 in which the outlet hole 60 and the inlet hole 70 for the refrigerant are drilled and the fitting seats for the pipes 2 and 3 are provided at the edges of the holes is considered as a trial.

The bottom surface of the plate-like joint member 5 has a refrigerant outlet and inlet hole 60.
And 70 so that the bottom edge of
5D and 5E are provided, and a fitting groove 5C for the O-ring 11 is formed on the outer periphery of each by a cutting method.

To connect the box-type expansion valve 200 to the evaporator, the refrigerant outlet 21 and the refrigerant inlet 22 of the expansion valve 200 are fitted with the joint portions 5D and 5E of the plate-like joint member 5, respectively. Then, the refrigerant inlet pipe 2 and the outlet pipe 3 of the evaporator are respectively fitted into the pipe fitting seats provided on the upper surface of the joint member 5 and then brazed, so that the refrigerant outlet and inlet holes 60 and 70 are hermetically sealed. Connect them. a indicates a brazing point.

However, according to such an expansion valve connection method, since the plate-like joint member 5 made of a thick metal plate has a considerably large heat capacity, brazing joining with the pipes 2 and 3 may be insufficient. Extremely high And if a joint failure occurs, a very inefficient repair work is required.

In addition, the step of providing the fitting groove 5C of the gasket in the joint portions 5D and 5E of the plate-shaped joint member 5 by the cutting method is also a great obstacle for improving productivity.

It is an object of the present invention to provide an evaporator having a structure in which an expansion valve can be attached more efficiently and more reliably while maintaining a hermetic seal.

[Means for Solving the Problems] In order to achieve the above object, the evaporator according to the present invention has a flat tube group having a refrigerant inlet / outlet, which allows the refrigerant inlet and outlet of each tube to communicate with each other, and the adjacent flattened tubes. Under the condition that fins are interposed in the heat exchange space between the tubes, the heat exchange unit made by stacking and combining is provided with an inlet pipe and an outlet pipe for the refrigerant, and both of them are arranged in parallel next to each other. The evaporator has a structure in which the free end of the pipe is adjacent to the refrigerant outlet or inlet of the expansion valve. In the evaporator assembled by brazing, one end side is connected to the refrigerant inlet pipe and the other end side is expanded. A refrigerant inlet side pipe joint provided with a circumferential bulging portion on the other end side for connecting to the refrigerant outlet of the valve, and one end side connected to the refrigerant outlet pipe, and the other end side of the expansion valve. The other end for connecting to the refrigerant inlet A pair of pipe joint insertion notches for fitting the refrigerant outlet side pipe joint provided with a circumferential bulge and the refrigerant inlet side and outlet side pipe joints respectively from the peripheral edge of the plate surface. A plate-like joint member provided with a portion and the other end side of each of the refrigerant inlet side and outlet side pipe joints are fitted to the refrigerant inlet or outlet of the expansion valve, The plate-like joint member is configured to be in pressure contact with the refrigerant outlet and inlet forming surfaces of the expansion valve via an elastic seal member along the bulging portion.

[Operation] In the evaporator having the above-described configuration, at the time of brazing and assembling the heat exchange unit, the refrigerant inlet pipe and the outlet pipe of the unit are fitted with one end side of the refrigerant inlet side pipe fitting and one end side of the refrigerant outlet side pipe joint, respectively. And braze them together.

In order to connect the expansion valve to the heat exchange unit, the inlet side pipe joint and outlet side pipe joint of the refrigerant are fitted into the pipe insertion notches of the plate joint member, respectively, and the other end side of the joints of both pipes is connected. , When the plate-like joint member is pressed against the refrigerant inlet formation surface of the expansion valve under the condition that it is fitted to the refrigerant outlet or inlet of the expansion valve, the circumferential shape of both pipe joints Since the bulging portion is pressed between the plate-shaped joint member and the expansion valve together with the elastic seal member, the other ends of these pipe joints are firmly and airtightly connected and fixed to the refrigerant outlet or inlet.

EFFECTS OF THE INVENTION (a) Since it is not necessary to braze the plate-like joint member, the problem that the brazing work becomes difficult due to the excessive heat capacity of this member is solved.

(B) Since it is not necessary to provide a cutting groove for fitting the elastic seal member on the plate-like joint member, the structure of this member can be simplified.

[Embodiment] The configuration of the present invention will be specifically described below based on an embodiment shown in the drawings.

FIG. 1 and FIG. 2 show an evaporator for incorporation in an air conditioner for automobiles as one embodiment according to the present invention, and a mounting structure of a refrigerant inlet pipe and an outlet pipe of a heat exchange unit, respectively, and both of these. The mounting structure of the expansion valve on the free end of the pipe is depicted as an exploded view.

The evaporator of this embodiment basically has the same structure as the conventional evaporator shown in FIG. 7 to FIG. 9 except for the portion where the inlet and outlet pipes of the refrigerant are attached to the expansion valve. Therefore, the description will proceed below with reference to these figures.

For the tube plate 1 that constitutes the flat tube A, the shallow plate-like body can be obtained by plastically processing the material plate in which the A4004 grade brazing material is clad on both sides of the A3003 grade aluminum plate in advance. Is molded into.

Then, as shown in FIG. 1, the specific flat tubes A2 and A3 for mounting the refrigerant inlet pipe 2 or the outlet pipe 3 are provided at the upper end portions of the two tube plates 1 constituting these flat tubes. A semi-cylindrical bulge forming each half of the refrigerant inlet pipe 2 or the refrigerant outlet pipe 3 is formed integrally with the tube plate 1. Therefore, the flat tubes A2 and A3 made by pasting these two tube plates 1 together,
An inlet pipe 2 and an outlet pipe 3 for the refrigerant are respectively installed. Although not clearly shown in this figure, the refrigerant inlet pipe 2 is the refrigerant inlet tank portion of the flat tube A2.
1A, and the refrigerant outlet pipe 3 is provided with a shape that communicates with the refrigerant outlet tank portion 1A of the flat tube A3.

The expansion valve 200 is of a type called a box type, and on the bottom surface of the valve box 20 made of metal and having a rectangular parallelepiped shape, a refrigerant outward pipe 31 and a return pipe 32 are connected to joint members 33 and 34. Are connected using. Further, on the top surface of the valve box 20, there are provided a refrigerant outlet 21 provided with a seat 21A of the refrigerant inlet side pipe joint 6 and a refrigerant inlet 22 provided with a seat 22A of the refrigerant outlet side pipe joint 7. There is. 24 is a refrigerant outlet 21 and an inlet
It is a diaphragm chamber that accommodates a diaphragm that is displaced according to the degree of superheat of the refrigerant between 22. Although illustration of the internal structure of the valve box 20 is omitted, a valve body and a valve body for increasing or decreasing the refrigerant flow rate at the refrigerant outlet 21 in accordance with the degree of superheat of the refrigerant at the refrigerant inlet 22 are provided in the valve box. A valve seat and a valve rod for transmitting the movement of the diaphragm to the valve body are incorporated.

The refrigerant inlet side pipe joint 6 and the refrigerant side pipe joint 7 have the same shape, and the pipe made of A3003 grade aluminum or the like is subjected to plastic working and is shown in FIG. 1 and FIG. It has an L-shape. On the other end side (the lower end side in the figure) of these joints, a circumferential bulged portion 6A or 7A that serves as a seat for the O-ring 11 as an elastic seal member is formed by the bulging method.

The plate-shaped joint member 5 is made of a thick aluminum plate having the same rectangular shape as the top surface of the expansion valve 200, and is fitted with a refrigerant inlet side pipe joint 6 and a refrigerant side pipe joint 7 from the peripheral edge of the plate surface. A pair of pipe joint insertion notches 8 and 9 are provided at a predetermined interval. The joint member 5 serves to hermetically join and fix the other ends of the pipe joints 6 and 7 to the refrigerant outlet 21 and the refrigerant inlet 22 of the expansion valve 200, respectively. Therefore, the top surface of the valve box 20 is provided with one or more threaded screw holes 23 for fastening bolts 25 as fastening means for fastening the plate-shaped joint member 5 to the top surface. Reference numeral 10 denotes a hole for inserting the bolt 25, which is formed in the plate-like joint member 5.

In FIG. 5, a box-type expansion valve 200 is attached to the heat exchange unit 100, and the expansion valve 200 further has a refrigerant forward pipe 31 and a return pipe 3
It is the sketch which showed the state which is going to connect 2.
Reference numeral 16 in the figure is a side plate for protecting both side ends of the heat exchange unit 100.

As described above, the method of assembling the evaporator described above uses the flat tube A as a superposed body of two ordinary tube plates 1.
FIG. 5 shows specific flat tubes A2 and A3, which are formed by superimposing a plurality of specific tube plates on which a plurality of pipes and a refrigerant inlet pipe 2 or outlet pipe 3 are integrally formed. After stacking under the arrangement, the side plates 16 are applied to both side ends of the stacked body, and this temporary assembled state is fastened and fixed using a jig.

Then, the refrigerant inlet pipe 2 and the outlet pipe 3 are fitted with the refrigerant inlet side pipe joint 6 or outlet side pipe joint 7, respectively, and further as shown in FIG. A plate-like joint member 5 is provided at the other end of both pipe joints 6 and 7.
To fix the mutual positional relationship of both joints. However, the plate-shaped joint member 5 may be fitted after the brazing process. Both pipe joints 6 and 7 are pre-clad with a brazing filler metal on their surfaces, if necessary.

Then, the temporary assembly is placed in a brazing furnace and heated to the melting temperature of the brazing filler metal so that the adjacent corrugated fins 15 and the corrugated fins 15 and the side plates 16 are separated from each other. The main assembly of the heat exchange unit 100 is completed extremely efficiently by brazing and joining the spaces.

At the same time, the refrigerant inlet pipe 2 and the refrigerant outlet side pipe joint 6
The fitting gap between and the fitting gap between the pipe 3 and the pipe joint 7 are also brazed, so that the fitting portion is joined more firmly and surely in a hermetically sealed state.

In order to assemble the box-type expansion valve 200 to the evaporator to which the plate-shaped joint member 5 is attached, the pipe joints 6 and 7 which are fitted to the plate-shaped joint member 5 are shown at the lower ends of FIG. Fit the O-ring 11 as described above, and attach each lower end to the valve box 20.
It may be inserted into the refrigerant outlet 21 and the inlet 22 and the plate-like joint member 5 may be fastened to the top surface of the valve box 20 with the fastening bolts 25.

As described above, the refrigerant outward pipe 31 and the return pipe 32 are connected to the bottom of the valve box 20.

FIG. 3 and FIG. 4 are embodiment diagrams showing another example of the shape of the plate-like joint member forming the constituent element of the evaporator of the present invention.

The plate-like joint member 5 of FIG. 3 is provided with notches 8 and 9 for inserting pipe joints on each of the opposite short sides of the member 5.

Further, the plate-like joint member 5 of FIG. 4 is provided with notches 8 and 9 on opposite long sides.

The heat exchange unit 100 and the expansion valve 200 shown in the above embodiment
The shape and structure of the above are merely disclosed as one specific example, and for example, the flat tube A that constitutes the heat exchange unit 100.
Design items such as which one of the groups is selected as the specific flat tubes A2 and A3 or how the plate-like joint member 5 and the valve box 20 are fastened are appropriately selected as necessary. Even if changed, the object of the present invention can be achieved.

Further, it can be applied not only to the type in which the tank is provided only on one side at the upper end as in the above embodiment, but also to the laminated evaporator having two tanks at the upper and lower ends.

[Brief description of drawings]

FIG. 1 and FIG. 2 are views of a first embodiment of the evaporator of the present invention, and show exploded structures of the expansion valve mounting structure to the refrigerant inlet and outlet pipes of the evaporator, respectively. 3 and 4 are perspective views showing a second embodiment and a third embodiment of the shape of the plate-like joint member which is a constituent element of the evaporator of the present invention. FIG. 5 is a sketch showing a state in which the expansion valve is attached to the evaporator. FIG. 6 is an explanatory view of a mounting structure showing one tentative method of mounting the expansion valve on the evaporator. 7 to 9 are views relating to a conventional evaporator, respectively, FIG. 7 is an external view, FIG. 8 is a plan view of a tube plate, and FIG. 9 is a side sectional view of a flat tube. . In the figure, 1 ... Tube plate, 1A, 1B ... Refrigerant inlet and outlet,
2, 3 ... Refrigerant inlet pipe and outlet pipe, 5 ...
Plate-shaped joint members, 5A, 5B ... seats, 8, 9 ... notches for inserting pipe joints, 6, 7 ... refrigerant inlet side pipe joints and outlet side pipe joints, 6A, 7A ... circumferential expansion Debe, 11 …… O
Rings, 21, 22 ... Expansion valve refrigerant outlet and inlet, 25 ...
… Fastening means, 100… Heat exchange unit, 200… Expansion valve,
A: Flat tube, B: Air gap for heat exchange

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Takeshi Kojima, 1-1, Showa-cho, Kariya city, Aichi Prefecture, Nihon Denso Co., Ltd. (72) Yoshifumi Ueno, 1-1, Showa-cho, Kariya city, Aichi prefecture, Nihon Denso Co., Ltd. Incorporated (56) References JP 59-225702 (JP, A) Actually opened 63-87477 (JP, U) Actually opened 63-7723 (JP, U) Actually opened 60-82170 (JP, U)

Claims (1)

[Claims] 1. A flat tube group having a refrigerant inlet / outlet is communicated with the refrigerant inlet and outlet of each tube, and fins are interposed in a heat exchange space between adjacent flat tubes. A heat exchange unit made by stacking and stacking is provided with a refrigerant inlet pipe and an outlet pipe, and a structure in which the free ends of both of these pipes which are juxtaposed in parallel are adjacent to the refrigerant outlet or inlet of the expansion valve. In the evaporator assembled by brazing, one end side is connected to the refrigerant inlet pipe, and the other end side is connected to the refrigerant outlet of the expansion valve. A refrigerant inlet side pipe joint is provided, and a circumferential bulge portion is provided on the other end side for connecting one end side to the refrigerant outlet pipe and the other end side to the refrigerant inlet of the expansion valve. A refrigerant outlet side pipe joint, and an inlet side of the refrigerant And a pipe joint member provided with a pair of notches for inserting pipe joints for fitting the pipe joints on the outlet side from the peripheral edge of the plate surface, and the pipe joints on the inlet side and the outlet side of the refrigerant, respectively. When the other end side is fitted to the refrigerant inlet or outlet of the expansion valve, the plate-shaped joint member is expanded by the elastic seal member along the circumferential expansion portion. An evaporator comprising a fastening means for press-contacting the refrigerant outlet and inlet forming surfaces of the valve.