JPH0611211A - Piping connector for heat exchanger - Google Patents

Abstract

PURPOSE:To make automatic welding practical and stabilize the quality after welding by a method wherein the open end of a refrigerant container, the end of an inner pipe and the end of a piping are integrally welded into a piece. CONSTITUTION:An open end 11a of a refrigerant container 11 of an accumulator 10, an end 12a of an inner pipe 12 and an end 4a of a piping 4 are integrally jointed into a piece by means of TIG-welding. The outward protruding brim at the tip of the inner pipe 12, which is formed by expanding the pipe, melts away and disappears after welding, and an annular bead 20 is formed. Thereby, as a plane part, where the open end 11a of the refrigerant container 11, the inner pipe end 12a and the piping end 4a overlap each other, is welded, it does not melt away. In addition, since it is a triple-overlapping construction of the open end 11a of the refrigerant container 11, the inner pipe end 12a and the piping end 4a, the quality after welding is stabilized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger pipe connecting device used for connecting a pipe for circulating a refrigerant from an evaporator to an accumulator in a refrigerating cycle of a refrigerator, for example.

[0002]

2. Description of the Related Art Conventionally, in a refrigerating cycle of a refrigerator, a system for decompressing by using a capillary tube is used, so that the flow rate of the refrigerant is constant irrespective of load fluctuation. Therefore, an accumulator is placed on the evaporator side,
The refrigerant liquid is stored so that it does not go directly to the compressor due to load fluctuations, gasifies it, and then sends it to the compressor.

[0003] In general, when considering quietness, such as in a domestic refrigerator, an inner pipe is provided inside the accumulator so that the refrigerant liquid from the evaporator is stored in the refrigerant liquid stored in the accumulator. Are designed to not pass directly.

[0004]

On the other hand, from the viewpoint of weight reduction, while evaporators made of all-aluminum are in widespread use,
In particular, the pipe connected to the accumulator is attached by TIG welding, but as shown in, for example, Japanese Utility Model Publication No. 63-2190, a state where the end of the pipe of the evaporator is simply butted against the end of the inner pipe of the accumulator. However, there is a problem in that there is a gap when welding is performed, so that automatic welding is difficult and the welding is not stable. Because during welding, the initial current concentrates on the end of the pipe, so the edge of the pipe melts and a hole opens,
This is because leaks will occur.

An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a heat exchanger pipe connecting device capable of automatic welding and stabilizing the quality after welding. There is.

[0006]

In order to achieve the above object, the present invention comprises a heat exchanger pipe made of aluminum, which is provided with a refrigerant accommodating portion and an inner pipe inserted from the opening end thereof. A device for connecting to a device such as an aluminum accumulator, in which one end of the inner pipe is located inside the opening end of the refrigerant container of the device, and the end of the pipe is located at the same end of the inner pipe. And a stainless steel backing sleeve is fitted inside the end of the pipe, and the opening end of the refrigerant accommodating part, the end of the inner pipe, and the end of the pipe are The gist is a connecting device for heat exchanger pipes, which are integrally connected by welding.

[0007]

According to the above heat exchanger pipe connecting device, the opening end of the refrigerant accommodating portion of the instrument such as the accumulator, the end of the inner pipe, and the end of the pipe are not formed at the butted portions of the pipe. Since the so-called planar portions that are overlapped are integrally joined by welding, there is no burn-through. Also,
The initial current value can be set high by the so-called triple lap structure of the opening end of the refrigerant accommodating portion, the inner pipe end, and the pipe end.

[0008]

Embodiments of the present invention will now be described with reference to the drawings.

Embodiment 1 First, referring to FIG. 3, an aluminum evaporator (1) used in a refrigerating cycle of a domestic refrigerator, for example, has a large number of plate fins (2) in a straight line portion of a meandering refrigerant flow pipe (3). Are orthogonally attached, and a pair of side plates (5) and (5) are arranged on both left and right outer sides of the plate fin (2).
An accumulator (10) made of aluminum is arranged on the left side of the evaporator (1) to prevent the refrigerant liquid from directly flowing to the compressor (not shown) due to load fluctuation.
The refrigerant liquid is stored in (0), and the refrigerant after being gasified is sent to the compressor. Inside the accumulator (10), considering the quietness of the refrigerator,
The inner pipe (12) made of aluminum is inserted to remove the refrigerant liquid stored in the accumulator (10) from the evaporator.
It is designed so that the refrigerant liquid from (1) does not pass directly through it. A meandering heating pipe for defrosting (6) is attached to both front and rear edges of the parallel plate fins (2).

As shown in detail in FIGS. 1 and 2, the evaporator
Piping (4) extending the end of the meandering refrigerant flow pipe (3) of (1)
However, an accumulator is provided by the pipe connecting device according to the present invention.
It is connected to the refrigerant containing portion (11) of (10) and the inner pipe (12).

That is, first, in the combined state before welding, as shown in FIG. 1, the end portion of the inner pipe (12) is
(12a) is expanded to form an outward convex edge (14) at the tip and an annular step (13) is formed near the tip. Then, the inner pipe (12) is inserted into the refrigerant accommodating portion (11) of the accumulator (10) from its opening end (11a), and the outer convex edge (14) at the tip of the inner pipe (12) is the refrigerant. The end portion (12a) of the inner pipe (12) is engaged with the open end of the containing portion (11) so that the open end portion of the refrigerant containing portion (11) is
It is located inside (11a).

The end portion (1) of the inner pipe (12) is
2a), a stainless steel backing sleeve (15) having an annular outer convex portion (16) in the middle of the length is inserted, and the outer convex portion (16) of the sleeve (15) is inserted into the inner pipe ( 12) Ring step
The sleeve front half part (15a), which is engaged with the (13) and is located in front of the outer convex part (16), is inserted further into the annular step part (13). Also, the end of this inner pipe (12)
The end (4a) of the pipe (4) of the evaporator (1) is inserted into (12a) so as to fit over the latter half (15b) of the sleeve (15), and the end of the pipe (4) The tip is abutted against the outer convex portion (16) of the sleeve (15), and the sleeve (15) straddles the end (4a) of the pipe (4) and the end (12a) of the inner pipe (12). It is made to exist so as to rise.

In this state, the opening end portion (11a) of the refrigerant accommodating portion (11) of these accumulators (10) and the inner pipe (1)
The end portion (12a) of 2) and the end portion (4a) of the pipe (4) are integrally connected by TIG welding.

After welding, as shown in FIG. 2, the outer convex edge (14) at the tip of the inner pipe (12) formed by expanding the pipe.
Melted away and formed an annular weld bead (20).

As described above, according to the present invention, the opening end portion (11a) of the refrigerant accommodating portion (11), the inner pipe end portion (12a), and the pipe end portion are not formed in the conventional pipe butting portion. There are no burn-throughs because the planar part that overlaps with (4a) is welded.

Further, the initial current value can be set high by the triple lap structure of the opening end (11a) of the refrigerant containing portion (11), the inner pipe end (12a) and the pipe end (4a). Therefore, the quality after welding can be stabilized.

Embodiment 2 FIG. 4 shows a second embodiment of the present invention. Here, the point different from the case of the first embodiment is that an annular outer convex portion (17) is provided in the portion near the tip of the aluminum pipe (4) by so-called beading, and the annular outer convex portion is formed. The outer convex part (16) of the stainless steel backing sleeve (15) is fitted into the annular groove (17a) inside the (17), and the sleeve (15) is positioned. is there.

The end portion (12a) of the inner pipe (12) is not expanded and is straight.
2) is inserted into the refrigerant accommodating portion (11) of the accumulator (10), and the end portion (12a) of the accumulator (10) is opened at the end portion (11) of the refrigerant accommodating portion (11).
It is located inside a). Then, the end (4a) of the pipe (4) accommodating the stainless steel backing sleeve (15) is fitted into the end (4a) of the inner pipe (12). ), Until the tip of the inner pipe (12) hits, the backing sleeve (15) is made to exist so as to straddle the pipe end (4a) and the inner pipe end (12a). There is.

Then, the opening end portions of these refrigerant accommodating portions (11)
(11a), the end (12a) of the inner pipe (12), and the pipe
The end (4a) of (4) is integrally joined by welding.

In this second embodiment, as shown in FIG. 5, a stainless steel backing sleeve (15) having an outer convex portion (16) in the middle of its length is of an oval shape. It was used.

This backing sleeve (15) has a relatively large opening in a normal state, as shown in FIG.
(18) is opened, and when it is inserted into the end (4a) of the pipe (4), the sleeve (15) is contracted and inserted as shown in FIG. And the end of the pipe (4)
After being inserted into the (4a), the sleeve (15) is firmly fixed to the inner surface of the pipe end (4a) by the so-called springback of the sleeve (15) itself.

Further, such a backing sleeve (15) has, for example, a circular oval shape as shown in FIG. 6, but in an ordinary state, almost no opening (18) is formed (the same). (See Fig. A), and the edges on both sides of the sleeve (15) opening
(19) (19) is cut diagonally and the end (4a) of the pipe (4)
When the sleeve (15) is retracted during insertion into the opening (1
The side edges (19) and (19) of 8) may be overlapped with each other (see FIG. 8B). Even in this case, after inserting the pipe (4) into the end (4a), the sleeve
The point that the sleeve (15) is firmly fixed to the inner surface of the pipe end (4a) by the springback of the (15) itself is the same.

According to these examples of FIGS. 5 and 6, the sleeve
It is easy to insert (15) into the end (4a) of the pipe (4), and after insertion, it is firmly fixed to the inner surface of the pipe end (4a), making welding work extremely easy. In addition, there is an advantage that it can be surely performed.

In the above embodiment, the pipe (4) extending the end of the meandering refrigerant flow pipe (3) of the evaporator (1) according to the present invention is the refrigerant accommodating portion (11) of the accumulator (10). Connected to the inner pipe (12) and the evaporator (1)
However, in the case where it is made by other roll bond method, the outer end portion of the pipe attached to the end portion of the refrigerant passage of this is the refrigerant accommodating portion (11) of the accumulator (10) as well. And the inner pipe (12).

Also, in the embodiment, a sleeve for backing
The outer convex portion (16) of (15) is formed in an annular shape, but it may be a partially protruding portion. Also, when using a backing sleeve (15) with an oval shape and using the springback of the sleeve (15) itself to fix the sleeve (15) to the inner surface of the pipe end (4a). May not be provided with the annular outer convex portion (16).

The present invention also relates to piping from the evaporator (1).
Not only when connecting (4) to the refrigerant accommodating part (11) of the accumulator (10) and the inner pipe (12), but also to connect the pipes from other heat exchangers to the receiver (receiver dryer). The same can be applied to the case of connecting to an instrument made of aluminum provided with such a refrigerant accommodating portion and an inner pipe.

[0027]

As described above, the present invention provides an instrument such as an accumulator made of aluminum, which has a heat exchanger pipe made of aluminum and is provided with a container for accommodating a refrigerant or the like and an inner pipe inserted through an opening end thereof. A device to connect to,
One end of the inner pipe is positioned inside the opening end of the refrigerant container of the device, the end of the pipe is inserted into the same end of the inner pipe, and the inside of the end of the pipe is made of stainless steel. A sleeve for backing is fitted,
The opening end of the refrigerant accommodating portion, the end of the inner pipe, and the end of the pipe are integrally joined by welding, and a planar part is used instead of the abutting part of the pipe as in the past. Since they are welded, there is no melt-through, and it is possible to avoid deterioration of quality due to melt-out of the pipe end surface, and automatic welding is possible.

Further, since the initial current value can be set high by the triple lap structure of the opening end of the refrigerant accommodating portion, the inner pipe end and the pipe end, the quality after welding is stabilized. There is an effect that can be measured.

[Brief description of drawings]

FIG. 1 is an enlarged side view of an essential part of a connecting portion between a heat exchanger pipe and an accumulator according to a first embodiment of the present invention, showing a combined state before welding.

FIG. 2 is an enlarged side view of an essential part of a connecting portion between the pipe and the accumulator, showing a state after welding.

FIG. 3 is a schematic front view of an evaporator including an accumulator.

FIG. 4 is an enlarged side view of an essential part of a connecting portion between a heat exchanger pipe and an accumulator according to a second embodiment of the present invention.

FIG. 5 is an enlarged end view showing one example of a stainless steel backing sleeve. FIG. 5A shows a normal state of the sleeve.
FIG. 5B shows the state in which the sleeve is contracted.

6 is an enlarged end view showing another example of a stainless steel backing sleeve, FIG. 6A showing a normal state of the sleeve, and FIG. 6B showing a state in which the sleeve is contracted.

[Explanation of symbols]

1 Evaporator 3 Serpentine Refrigerant Flow Pipe 4 Piping 4a End 10 Accumulator (Instrument) 11 Refrigerant Storage Part (Refrigerant Storage Part) of Accumulator 11a Open End 12 Inner Pipe 12a End 15 Stainless Steel Backing Sleeve 16 Outward convex

Claims (1)

[Claims] 1. A heat exchanger pipe made of aluminum (4)
Is a device for connecting to a device (10) such as an accumulator made of aluminum, which is provided with a refrigerant containing portion (11) and an inner pipe (12) inserted through an opening end portion (11a) of the refrigerant. Inside the opening end portion (11a) of the refrigerant containing portion (11) of 10),
One end (12a) of the inner pipe (12) is positioned,
Connect the end (4) of the pipe (4) to the same end (12a) of the inner pipe (12).
a) is inserted and a stainless steel backing sleeve (15) is fitted inside the end (4a) of the pipe (4), and the opening end ( 11a), the end portion (12a) of the inner pipe (12), and the end portion (4a) of the pipe (4) are integrally joined by welding, and a connecting device for heat exchanger pipes.