JPH0871740A - Brazing production method of aluminium hosefitting - Google Patents

Abstract

PURPOSE: To eliminate T6 treatment executed after brazing by preventing the hose mounting part of rear end side from temp. rise and lowering of hardness in brazing of Al hose fitting, in which a flange for joining and short tube branch for flange/valve mounting are brazed to the tip part of short tube shape fitting main body. CONSTITUTION: In brazing a flange 2 and short tube branch 3, a copper cooling cylinder 10, in which a main body inner diameter is made to a ventillating part 11 and is slightly larger than the outer diameter of fitting main bodies 1, 1' and a tip inner diameter part is made to an engaging/closing part 12 and is reduced to the diameter to be fitted/brought into tight contact with the groove 1c of hose mounting part 1b of fitting main bodies 1, 1', is mounted on the hose mounting part 1b of fitting main bodies 1, 1'. While a compressed air A is continuously supplied from a supplying hole 13 of the tip part of cooling cylinder 10 to the inside and is injected from rear end side, the brazing is executed by heating the inner peripheral part of flange 2 and peripheral part of short tube branch 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aluminum hose fitting, and more particularly, a hose for piping for connecting a compressor, an evaporator, etc., which is a main component of a car cooler, to circulate a refrigerant. To a brazing method for manufacturing an Al hose fitting.

[0002]

2. Description of the Related Art A hose fitting for a piping hose for connecting a compressor, an evaporator or the like, which is a main component of a car cooler, to circulate a refrigerant, is made of Al, which is lightweight and excellent in specific strength. As shown in (a) of the perspective view of FIG. 4, a plurality of parts for caulking the hose (H) are provided at the front end while the insertion part (1a) for the counterpart device is provided at the front end. Hose fitting part formed by surrounding the groove (1c)
It has a short tubular base body (1) provided with (1b), an insertion hole (2a) and a fastening bolt hole (2b), and the tip of the base body (1) is inserted into the insertion hole (2a). And a flange (2) fixed by brazing to the tip portion following the insertion portion (1a) of the mouthpiece body (1), as shown in (b) FIG.
In addition to the above flange (2), the flange (2) of the base body (1)
Widely used is a structure in which a branch short pipe (3) for mounting a refrigerant charge valve is attached by brazing at a site located between the hose fitting part (1b) and the hose fitting part (1b). There is.

And, in these Al hose fittings,
On its base body (1), the flange (2) and the branch short pipe (3)
When brazing, generally heat the larger mass, that is, when brazing the flange (2) on the base body (1) by brazing, the inner circumference of the flange (2) When the branch short pipe (3) is inserted into the prepared hole provided in the mouthpiece main body (1) and brazed, the mouthpiece main body (1) around the branch short pipe (3) is Brazing is performed by heating.

The hose (H) connected to these Al hose fittings has its tip end fitted to the hose fitting portion (1b) of the base body (1) as shown in the diagram (c). ), And a metal outer cylinder that covers the outer circumference
By being crimped by (S), its inner peripheral side is bited into the groove (1c) of the hose fitting portion (1b), and firmly so that airtightness with the mouthpiece main body (1) can be secured. It is crimped. Further, the tip of the outer cylinder (S) is locked in the groove (1c) at the forefront of the hose fitting portion (1b) by caulking.

[0005]

By the way, since the Al material is also excellent in thermal conductivity, in the hose mouth fitting having the above structure, the tip of the mouthpiece body is heated by the heating during brazing work of the flange and the branch short pipe. The heat is easily transferred not only to the hose fitting part on the rear end side, but especially to the hose fittings where the distance between the brazing part and the hose fitting part is short. By the heat
There is a problem that the hardness of the hose fitting portion of the base body is softened. Therefore, if the hose is left as it is, it will be easily deformed at the time of crimping the hose, and it will be difficult to ensure airtightness, that is, it will not be able to satisfy the specified hardness. The effect hardness (T6 treatment) is applied to satisfy the specified hardness, which is an obstacle to improving productivity and reducing cost.

The present invention has been made in order to solve the above-mentioned problems of the prior art. The hose is fitted to the rear end of the mouthpiece by heating when brazing the flange and the branch short pipe to the tip of the base body. A method for brazing an aluminum hose fitting, which can suppress the temperature rise of the part and decrease in hardness, thereby improving productivity and reducing costs by eliminating the T6 treatment after brazing, which has been performed in the prior art. The purpose is to provide.

[0007]

In order to achieve the above object, the present invention has the following constitution. That is, the brazing method for manufacturing an Al hose fitting according to the present invention is
A short tube-shaped mouthpiece body having an insertion portion into the other device at the tip and a hose fitting portion having a plurality of grooves around the rear end for crimping the hose, and this mouthpiece body A brazing method of an Al hose mouth fitting comprising a connecting flange brazed to the tip portion following the insertion portion of the above, or a branch short pipe for mounting the flange and the valve, the method comprising: When brazing the flange and the branched short pipe to the tip portion, the inner diameter of the main body portion is made slightly larger than the outer diameter of the hose fitting portion on the hose fitting portion at the rear end portion of the mouthpiece body, and A cooling cylinder whose inner diameter is reduced so as to be in close contact with the outer circumference of the hose fitting part is arranged, and compressed air is continuously fed to the inside through an air supply hole provided at the tip of this cooling cylinder. The inner peripheral surface of the cooling cylinder and the outer peripheral surface of the hose fitting portion While spraying from the rear end side through the gap of No. 1, while heating the mouthpiece main body portion around the flange inner circumference and the branch short pipe, the flange and the branch short pipe are brazed to the tip end of the mouthpiece main body. .

Further, the cooling cylinder is made of a metal material and is vertically divided into two parts, and the inner diameter of the main body is larger than the outer diameter of the hose fitting part within a range of 0.4 mm to 4.0 mm. The diameter of the hose, and the inner diameter of the tip is reduced to a diameter that fits and fits in the groove of the hose fitting part, and the reduced diameter part is fitted in the groove located at the forefront of the hose fitting part. May be arranged on the hose fitting portion.

Further, the pressure of the compressed air fed into the cooling cylinder may be 0.1 MPa to 0.3 MPa.

[0010]

According to the present invention, when the flange and the branch short pipe are brazed to the front end of the short tubular mouthpiece body having the hose fitting portion at the rear end, the hose fitting portion at the rear end portion is brazed. A cooling cylinder having an inner diameter of the main body portion slightly larger than the outer diameter of the hose fitting portion and a diameter of the tip inner diameter reduced to a diameter in close contact with the outer periphery of the hose fitting portion is arranged. At the same time, compressed air is continuously supplied to the inside through an air supply hole provided at the tip of the cooling cylinder, and is ejected from the rear end side through the gap between the inner peripheral surface of the cooling cylinder and the outer peripheral surface of the hose fitting portion. While letting
The flange and the branch short pipe are brazed to the tip of the base by heating the inner circumference of the flange and the base of the branch short pipe. Even if it is transmitted to the hose fitting part, the hose fitting part is cooled by heat exchange by compressed air flowing between the outer peripheral surface of the hose fitting part and the inner circumferential surface of the cooling cylinder, and the hose fitting part is prevented from rising in temperature and decreasing in hardness. it can. Further, since the compressed air sent into the cooling cylinder is jetted from the rear end side, it does not hinder the heating of the inner peripheral portion of the flange on the front end side and the main body of the branch short pipe, and the rear end side. While effectively cooling the hose fitting part, the flange and the branch short pipe can be brazed to the tip part with desired efficiency.

The cooling cylinder is made of a metal material and is vertically divided into two parts, and the inner diameter of the main body is larger than the outer diameter of the hose fitting part within a range of 0.4 mm to 4.0 mm. At the same time, the inner diameter of the tip portion is reduced to a diameter that fits and adheres into the groove of the hose fitting portion, and the reduced diameter portion is fitted into the groove located at the forefront of the hose fitting portion, By arranging the cooling cylinder on the hose fitting part, the cooling cylinder can be easily attached to and detached from the hose fitting part of the base body and positioned in the axial direction, and the thermal conductivity of the cooling cylinder itself is enhanced to achieve a cooling effect. Can be improved. Here, the inner diameter of the main part of this cooling cylinder is 0.4 mm to 4.0 mm smaller than the outer diameter of the hose fitting part.
A large diameter within the range of mm means that the gap between the inner peripheral surface and the outer peripheral surface of the hose fitting is 0.2 mm or less, the flow resistance to the flow of compressed air becomes too high, and However, if the flow rate is 2.0 mm or more, compressed air will blow out from the rear end side without evenly contacting the outer peripheral surface of the hose fitting, and the cooling effect will be uneven. Because it will be.

The pressure of the compressed air fed into the cooling cylinder is 0.1 MPa when brazing only the flange, that is, when the flange is heated and brazed. By doing so, it is possible to sufficiently cool the hose fitting part and suppress hardness decrease, but when brazing a short branch pipe between the flange and the hose fitting part, that is, the base body part around the short branch pipe. When heating and brazing too,
Since the amount of heat transferred from the heating part to the hose fitting part increases, it is necessary to feed the hose fitting part at a pressure of at least 0.2 MPa in order to sufficiently cool the hose fitting part and suppress the decrease in hardness. On the other hand, if the pressure is higher than 0.3 MPa, the cooling effect on the hose fitting part on the rear end side becomes excessive, and the temperature on the front end side decreases accordingly, resulting in the brazing of the flange and the branch short pipe. It is not practical because it increases the heat input for the brazing, prolongs the brazing time, and also produces noise when ejecting from the rear end side of the cooling cylinder, so it is not practical. Pressure is 0.1MPa
The pressure is set within the range of to 0.3 MPa, preferably 0.2 MPa or more and less than 0.3 MPa.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. [FIG. 1] is a conceptual explanatory view of an embodiment of a brazing manufacturing method of the present invention. (A) and (b) are explanatory views of brazing work, and (c) is used for brazing. It is a perspective view showing a schematic structure of a cooling cylinder. First, outer diameter 14.5 mm, inner diameter 10.0 mm
It is made of Al pipe material and its tip is inserted into the other device.
(1a) is provided, and a plurality of grooves (1c) for caulking the hose (H) are provided at the rear end of the hose fitting (1a).
A 60 mm long base body (1) with b) and the same Al tube material. In addition to the above configuration, a 100 mm long base body (1 d) with a branching pilot hole (1 d) in the middle part ') And Al material,
The outer shape of the plane is a pair of large and small discs,
The larger disc has a through hole (2a) for inserting the base body (1), (1 '), and the smaller disc has a bolt hole (2b) for passing a fastening bolt. Flange (2), outer diameter 12m
A branch short pipe (3) having a length of 20 mm and made of an Al pipe material having a diameter of 8 mm and an inner diameter of 8 mm was prepared. Where the base body
(1), (1 ') has a hardness of Hv85, and the hose fitting portion (1b) at the rear end has four grooves (1c),
The length from the rear end to the end of the foremost groove (1c) is 30 mm, while the branching pilot hole (1d) of the base body (1 ') has a hose fitting (1
It is provided at a portion spaced 20 mm from the groove (1c) at the forefront of b).

On the other hand, the cooling cylinder (10) shown in FIG. 1 (c) is prepared. The cooling cylinder (10) is made of a copper material, and is divided into two parts in the vertical direction as shown in the same figure (c), and can be opened and closed by a hinge not shown here, and its main body is The inner diameter of the part is set as the ventilation part (11) to be 2.0 mm larger than the outer diameter of the mouthpiece main body (1), (1 '), and the inner diameter of the tip part is set to the engagement blocking part (12 ), The groove (1c) of the hose fitting (1b) of the base body (1), (1 ')
It is reduced in diameter and width so that it fits and fits inside. Also,
An air supply hole (13) that communicates the inside and the outside is provided at the tip of the ventilation part (11) near the engagement blocking part (12) side, and the length thereof is the base body (1), (1 ') Hose fitting part at the rear end
The length is set so that most of (1b) can be encapsulated.

Then, in the present embodiment, the flange (2) is brazed to the tip portion of the mouthpiece body (1) following the insertion portion (1a) by the following procedure, and (a) in FIG. ) Manufacture a hose mouth fitting having the configuration shown in the figure, that is, a hose mouth fitting having only a flange, and attach the flange (2) to the tip of the mouthpiece body (1 ') following the insertion portion (1a). , Furthermore, braze the branch short pipe (3) to the branch pilot hole (1d),
A hose mouth fitting having a structure shown in FIG. 4 (b), that is, a hose mouth fitting of a type including a flange and a branch short pipe was manufactured.

First, in brazing work of a hose mouth fitting of a type having only a flange, the tip of the mouthpiece main body (1) has a tip of 6 mm as shown in (a) of FIG.
Insert it so that it protrudes through the insertion hole (2a) of the flange (2),
I temporarily stopped in that state. Then, the cooling cylinder (10) is mounted on the hose fitting portion (1b) at the rear end of the base body (1). At this time, as shown in the same figure, the engagement closing part (12) at the tip of the cooling cylinder (10) is fitted into the groove (1c) located at the forefront part of the hose fitting part (1b). Then, the axial mounting position of this cooling cylinder (10) is determined, and the ventilation part (11)
While the front end side was closed, the rear end side was opened. Next, compressed air (A) from an air supply device (not shown here) is continuously supplied to the internal ventilation part (11) through the air supply hole (13) provided at the tip of the cooling cylinder (10). As shown by the arrow in the figure, while the gas is ejected from the rear end side through the gap between the inner peripheral surface of the ventilation part (11) and the outer peripheral surface of the hose fitting part (1b), inside the flange (2). The peripheral portion was heated and the flange (2) was brazed to the tip of the base body (1).

Further, in the brazing work of a hose mouth fitting of a type including a flange and a branch short pipe, the mouthpiece main body is used.
As shown in (b) of [Fig. 1], insert the tip of (1 ') into the insertion hole (2a) of the flange (2) and temporarily fix it, as well as the branch pilot hole. Insert the base end of the branched short pipe (3) into (1d) and temporarily fix it, and then on the hose fitting part (1b) at the rear end of the mouthpiece body (1 '), in the same way as above. After installing (10), first braze the flange (2) in the same procedure as above, and then continue to supply compressed air (A) to the cooling tube (10) while branching the short pipe (3). ) The periphery of the base body (1 ′) was heated and the branched short pipe (3) was brazed to the tip of the base body (1 ′).

Here, in this embodiment, the heating time around the flange (2) and the branch short pipe (3) performed under the above procedure is set to 40 seconds and 17 seconds which are standard in the conventional method. On the other hand, the pressure of the compressed air (A) sent to the cooling cylinder (10) was variously changed to perform brazing, and for comparison with the conventional technique, without using the cooling cylinder (10), that is, A comparative example was also carried out in which the hose fitting portion (1b) was brazed in the atmosphere without sending compressed air.

Then, for each obtained hose mouth fitting,
From the flange (2) of the base body (1) for the type with only a flange, from the branch short pipe (3) of the base body (1 ') for the type with a flange and a branch short pipe, respectively. The hardness of the part 30 mm away from the hose, that is, each hose fitting part (1b) was measured. The results are shown in the graph of FIG. The graph of FIG. 2 is a graph showing the relationship between the hardness of the hose fitting portion of the hose fitting of the present embodiment and the feed pressure of compressed air, and the plots with black circles in the graph are flanges. An example of brazing of a hose fitting having only one and the plots with open circles show an example of brazing of a hose fitting having a flange and a branch short pipe, respectively.

As shown in the graph of FIG. 2, in a hose mouth fitting of a type including only a flange, the flange side is heated during brazing, and the mouthpiece body is indirectly heated, so that it is fed to the cooling cylinder. Even if the compressed air to be used is a low pressure of 0.1MPa, the hose fitting part is sufficiently cooled to suppress the decrease in hardness and satisfy the specified hardness (Hv70 or more), while a flange and a branch short pipe are provided. When brazing a branch short pipe, a hose mouth fitting of the type directly heats the mouthpiece main body around the branch short pipe, so the amount of heat transferred from the heating section to the hose fitting section increases, and the hose fitting section is It was found that a pressure of 0.2 MPa or more is necessary to sufficiently cool and suppress the decrease in hardness. On the other hand, when feeding at a pressure of 0.3 MPa or more, the hose fitting part of both types is
It receives a cooling effect that can maintain the hardness (Hv85) before brazing, but if it exceeds 0.3 MPa, the cooling will be excessive and the brazing part on the tip side will also have a cooling effect, so the heating time of the brazing part It has been found that it is difficult to apply it practically because it needs to be greatly extended, and noise is generated when it is ejected from the rear end side of the cooling cylinder. Therefore, the pressure of the compressed air sent to the cooling cylinder is within the range of 0.1 MPa to 0.3 MPa for the hose mouth fitting of the type having only the flange, and 0.2 M for the hose mouth fitting of the type having the flange and the branch short pipe.
Within the range of Pa-0.3MPa, preferably 0.2M for both types
By setting the pressure within the range of more than Pa and less than 0.3 MPa, it is possible to prevent the hardness of the hose fitting part on the rear end side from rising due to heating during brazing and to reduce the hardness. It is possible to satisfy the specified hardness without performing T6 treatment after attachment.

Furthermore, in the above-mentioned embodiment, regarding the hose mouth fitting of the type having only the flange, the flange is provided under the condition that the pressure of the compressed air sent to the cooling cylinder is 0.2 MPa.
The heating time when brazing (2) was variously changed, and the relationship between the heating time and the hardness of the hose fitting part (1b) was investigated. The hardness was measured at a position 30 mm away from the rear end of the brazed flange (2) in the same manner as described above. The results are shown in the graph of FIG. The graph of FIG. 3 is a graph showing the relationship between the heating time of the brazing part and the hardness of the hose fitting part.

As shown in the graph of FIG. 3, when heating a portion close to the hose fitting portion with a distance of 14 mm, it is possible to perform indirect heating under optimal cooling conditions with a cooling cylinder. However, in order to secure the specified hardness (Hv70 or more), it was found that the heating time was limited to 50 seconds or less, and considering the safety due to work variations, it was about 40 seconds. On the other hand, the heating time of 40 seconds is the time standardized by the conventional method as described above, and from this, the deterioration of workability due to the cooling using the cooling cylinder is not recognized, and the brazing is performed. It was confirmed that the effect of the present invention can be sufficiently achieved as long as the heating time is appropriately controlled in accordance with the model and size of the hose mouth fitting to be constructed. The hose fitting in this embodiment has a very short distance between the brazing part and the hose fitting part of 14 mm to 20 mm, but when the distance is long, the hose fitting is Since the amount of heat transferred to the hose fitting portion is relatively small, it goes without saying that the heating time of the brazing portion can be appropriately lengthened accordingly. Further, as shown in FIG. 4, the hose mouth fitting obtained in this example has a hose (H) crimped to the hose fitting portion (1b) at the rear end and a branch short pipe ( In the one provided with 3), a charge valve is attached to the branch short pipe (3) and is used as a piping member for circulating the Kirkler's refrigerant.

In the above embodiment, the cooling cylinder (10) has a main body whose inner diameter is the ventilation portion (11), and is 2.0 mm larger than the outer diameter of the die body (1) to be constructed, and , The inner diameter of the tip, as the engaging block (12), the base body (1)
The hose fitting part (1a) has a configuration in which the diameter and width are reduced by fitting and fitting in the groove (1c) of the hose fitting part (1a), but this is an example, and the inner diameter of the main body part as the ventilation part is It has been confirmed through trials prior to the present example that the outer diameter of the hose fitting portion of the mouthpiece main body to be constructed should be larger within the range of 0.4 mm to 4.0 mm. And the reason is that if the gap between the inner peripheral surface of the ventilation part of the cooling cylinder and the outer peripheral surface of the hose fitting part is 0.2 mm or less, the flow path resistance against the flow of compressed air becomes too high, and the flow rate is correspondingly increased. The cooling effect decreases as the size decreases, and on the other hand, at 2.0 mm or more, compressed air blows out from the rear end side without evenly contacting the outer peripheral surface of the hose fitting, so the cooling effect becomes uneven. Is. Further, the cooling cylinder is made of a copper material, and the inner diameter of the tip portion is formed as an engagement closing portion which is fitted and closely fitted in the groove of the hose fitting portion. This is a preferable example, and thermal conductivity is high. It is possible to use metal materials other than copper materials as long as
Also, as long as the compressed air introduced into the ventilation part of the cooling cylinder can be closed so as not to be ejected to the brazing tip side, for example, the inner diameter of the tip part is the outer circumference of the hose fitting part of the mouthpiece body to be attached. It may be reduced in diameter so as to be in close contact with.

[0024]

As described above, according to the brazing manufacturing method of the present invention, the hose fitting on the rear end side is caused by the heating at the time of brazing the flange and the branch short pipe to the tip portion of the base body. It is possible to suppress a decrease in hardness due to a rise in temperature of the welded portion, and thus it is possible to improve productivity and reduce cost of the Al hose mouth fitting without the need for the T6 treatment after brazing, which has been performed in the prior art. .

[Brief description of drawings]

FIG. 1 is a conceptual explanatory view of an embodiment of a brazing manufacturing method of the present invention, wherein (a) and (b) are explanatory views of brazing work, and (c) is a cooling used for brazing. It is a perspective view showing a schematic structure of a cylinder.

FIG. 2 is a graph showing the relationship between the hardness of the hose fitting portion and the compressed air supply pressure in the hose fitting according to the embodiment of the present invention.

FIG. 3 is a graph showing the relationship between the heating time of the brazing part and the hardness of the hose fitting part in the hose fitting according to the embodiment of the present invention.

FIG. 4 is a perspective view showing a typical configuration of an aluminum hose fitting for a car cooler.

[Explanation of symbols]

 (1) --Mouthpiece body (1 ')-Mouthpiece body (1a)-Insert part (1b)-Hose fitting part (1c)-Groove (1d)-Branching pilot hole (2)- -Flange (2a)-Insertion hole (2b)-Bolt hole (3)-Branch short pipe (10)-Cooling tube (11)-Vent (12)-Engagement block (13) --Air supply port (A) --Compressed air

Claims (3)

[Claims] 1. A short tubular mouthpiece main body having a distal end provided with an insertion portion for a counterpart device and a rear end provided with a hose fitting portion having a plurality of grooves for caulking a hose. And a brazing flange for connection or a branch short pipe for mounting the flange and a flange for connection, which is brazed to the tip portion following the insertion portion of the mouthpiece main body, and a brazing method for brazing an Al hose mouth fitting. When brazing the flange and the branch short pipe to the tip portion of the mouthpiece body, the main body inner diameter is slightly larger than the outer diameter of the hose fitting portion on the hose fitting portion at the rear end portion of the mouthpiece body. A cooling cylinder with a diameter that is reduced in diameter so that the inner diameter of the tip is in close contact with the outer circumference of the same hose fitting part is provided, and the inside is compressed through the air supply hole provided at the tip of this cooling cylinder. Air is continuously fed to the inner surface of the cooling cylinder and the hose. While spraying from the rear end side through the gap with the outer peripheral surface of the fitting part, heat the inner body of the flange and the main body of the base of the branch short pipe, and braze the flange and the short branch pipe to the tip of the base of the base. Al characterized by
Brazing method for hose mouth fittings. 2. The cooling cylinder is made of a metal material and is vertically divided into two parts, and the inner diameter of the main body is larger than the outer diameter of the hose fitting part within a range of 0.4 mm to 4.0 mm. At the same time, the inner diameter of the tip part is reduced to a diameter that fits and fits closely into the groove of the hose fitting part, and by fitting the reduced diameter part into the groove located at the forefront part of the hose fitting part. The brazing method for manufacturing an Al hose mouth fitting according to claim 1, wherein the brazing method is provided on the hose fitting portion. 3. The Al according to claim 1, wherein the pressure of the compressed air fed into the cooling cylinder is 0.1 MPa to 0.3 MPa.
Brazing method for hose mouth fittings.