JP2001235081A - Joint for double pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a joint for a double pipe suited for applying to the double pipe integrally molding an outer/inner pipe and a connection rib. SOLUTION: This joint 50 for a double pipe, used for connecting the double pipe 100 integrally molding an outer/inner pipe 101, 102 and a connection rib 103 by extrusion work or drawing work, has a main unit part 110 mounting one end in an outer pipe end part 101a exposing the inner pipe by removing partly the outer pipe, a wall surface part 112 provided in the other end of the main unit part to insert the exposed inner pipe, and a connection pipe 120 mounted in an opening 113 provided in the main unit part. The opening is formed in a position determined in accordance with an arranged condition of the connection pipe, so as to use in common the main unit part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a two-piece type wherein an outer tube, an inner tube provided inside the outer tube, and a connecting rib for connecting the two tubes are integrally formed by extrusion or drawing. The present invention relates to a double pipe joint used to connect heavy pipes.

[0002]

2. Description of the Related Art As is well known, a double pipe comprises an outer pipe through which a first fluid flows and an inner pipe provided inside the outer pipe and through which a second fluid flows. Have.
Broadly classified according to the manufacturing method, there are two types of double tubes. One is to manufacture the outer tube and the inner tube separately and independently, iron the outer tube with the inner tube inserted into the outer tube, and press the projection formed on the inner wall of the outer tube against the outer wall of the inner tube. It is a type of double pipe. The other one is an outer tube, an inner tube,
This is a double pipe of a type in which a connecting rib for connecting the outer pipe and the inner pipe is integrally formed by extrusion or drawing. In recent years, outer tubes,
A double pipe of the latter type, in which an inner pipe and a connecting rib are integrally formed, is often used.

Japanese Patent No. 2,595,578 describes a joint of a piping system having a double pipe structure of an outer hose and an inner hose made of rubber.

[0004] However, the joint structure described in the above publication can be applied when the outer tube and the inner tube are formed separately, but the joint structure in which the outer tube, the inner tube and the connecting rib are integrally formed. Not applicable to heavy pipes.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a double pipe joint which is preferably applied to a double pipe in which an outer pipe, an inner pipe and a connecting rib are integrally formed.

[0006]

The object of the present invention is achieved by the following means.

(1) An outer pipe through which a first fluid flows, an inner pipe provided inside the outer pipe through which a second fluid flows, and a connecting rib for connecting the two pipes are formed by extrusion or drawing. In the double-pipe joint used to connect the integrally-formed double pipe, one end is attached to an outer pipe end portion where a part of the outer pipe is removed to expose the inner pipe, and the exposed outer pipe is attached. A body portion surrounding the inner tube and having a passage for flowing the first fluid, a wall portion provided at the other end of the body portion, through which the exposed inner tube penetrates, and a body portion provided on the body portion. Opening, a connecting pipe attached to the opening and communicating with the passage, and a first connecting part provided at an end of the connecting pipe and connecting the connecting pipe to a first external pipe guiding the first fluid. And is provided at the end of the inner tube penetrating the wall portion,
A second connecting portion that connects the inner tube to a second outer tube that guides the second fluid, wherein the opening is formed at a position determined according to an arrangement state of the connecting tube, and the main body portion is formed. This is a double pipe joint characterized by being shared.

(2) The second connecting portion has a connecting portion formed integrally with the inner tube by processing a terminal portion of the inner tube and connected to the second outer tube. Is the joint for a double pipe according to the above (1).

(3) The double-pipe joint according to the above (1), wherein the wall surface has a concave portion for holding a joining material for joining the penetrating inner pipe.

(4) The double pipe according to the above (1), wherein the connection pipe has a connection part joined to the edge of the opening and expanded radially outward. It is a joint.

(5) The double-pipe joint according to (4), wherein the opening is formed so that an attachment position of the connection pipe with respect to the opening is adjustable.

(6) The double pipe joint according to (1), wherein the first connection portion and the second connection portion are configured as a flange type or a union type.

(7) The double pipe joint according to (6), wherein the first connection portion of the flange type and the second connection portion of the flange type are integrally formed. is there.

(8) The second connecting portion configured as a flange type has a through hole for inserting a fastening means, and the through hole is formed in a direction different from a direction in which the inner pipe penetrates a wall portion. The joint for a double pipe according to the above (6) or (7), wherein the joint is formed along.

(9) The outer pipe through which the first fluid flows, the inner pipe provided inside the outer pipe through which the second fluid flows, and the connecting rib connecting the two pipes are formed by extrusion or drawing. In the double pipe joint used to connect the integrally formed double pipe, a part of the outer pipe is removed, the outer pipe is attached to an outer pipe end that exposes the inner pipe, and the first fluid flows. A block-shaped main body having an internal passage formed therein; a first opening formed in the main body, which communicates the first external pipe for guiding the first fluid with the internal passage; and a first opening formed in the main body. A second opening communicating the inner fluid with a second outer pipe for guiding the second fluid, wherein the inner pipe exposed from the outer pipe terminal portion is substantially straight across the inner passage. A double pipe joint characterized by being stretched.

[0016]

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

FIG. 1 is a schematic configuration diagram showing an air conditioner for a vehicle according to an embodiment to which the joint for a double pipe of the present invention is applied, FIG. 2 is a cross-sectional view showing the joint for a double pipe according to the first embodiment, FIG. 3 is a perspective view showing a double pipe.

The vehicle air conditioner shown in FIG.
This is a dual-type automotive air conditioner used in a so-called one-box car or the like, and includes a front seat air conditioner 10 that mainly performs front seat air conditioning and a rear seat air conditioner 20 that mainly performs rear seat air conditioning. Prepare. The rear-seat air conditioner 20 is installed near the center or the rear of the vehicle interior. In each of the air conditioners 10 and 20 for the front seat and the rear seat, the air taken in by the intake units 11 and 21 is guided to the unit case,
The air is cooled by passing through the evaporators Ef and Er in the unit case, and the cooled air is heated by the heater cores Hf and Er.
After being heated by Hr or by bypassing the heater cores Hf and Hr, the air is mixed with the heated air to obtain warm air at a predetermined temperature, and then blown into the vehicle interior from various outlets 12 and 22. On the front surface of the heater cores Hf and Hr,
Mix doors 13 and 23 are provided rotatably for branching cooling air at a predetermined ratio into air passing through the heater cores Hf and Hr and air flowing bypassing the heater cores Hf and Hr.

The "evaporators Ef, Er" are, as is well known, a low-temperature, low-pressure refrigerant decompressed by expansion valves Vf, Vr and the like, and the air introduced therein is cooled by heat exchange with the refrigerant. Is what you do. Also, "Heater core H
“f, Hr” means that high-temperature engine cooling water flows through the inside, and the air introduced here is heated by heat exchange with high-temperature engine cooling water.

A cooling cycle is constituted by connecting the front evaporator Ef, the rear evaporator Er, the compressor 31, the condenser 32, the liquid tank 33, and the expansion valves Vf and Vr by refrigerant pipes. The relatively high-temperature and high-pressure liquid refrigerant flowing out of the liquid tank 33 is guided to each of the front evaporator Ef and the rear evaporator Er through refrigerant pipes 34 and 35 branched in the engine room. Also, the front evaporator Ef
The gaseous refrigerant having a relatively low temperature and a low pressure flowing out of each of the rear evaporator Er and the refrigerant is merged in the engine room through the refrigerant conduits 36 and 37, and is sucked into the compressor 31.

In the present embodiment, a double pipe is used for the refrigerant pipe connecting the rear evaporator Er and the cooling cycle, and the first double pipe 10 connected to the refrigerant pipes 35 and 37 is used.
0 and a second double pipe 200 connected to the rear evaporator Er. These two double tubes 100, 2
00 are mutually connected via a joint 40. Then, the low-pressure gaseous refrigerant from the rear evaporator Er (first
The fluid (corresponding to the fluid) flows through the outer tubes 101 and 201, and the high-pressure liquid refrigerant (corresponding to the second fluid) from the liquid tank 33 flows through the inner tubes 102 and 202. At the end of the first double pipe 100, via the double pipe joint 50,
The outer pipe 101 is connected to the refrigerant conduit 37 and the inner pipe 102 is connected to the refrigerant conduit 3.
5 respectively. At the end of the second double pipe 200, the outer pipe 201 is connected via the double pipe joint 60.
Is connected to the outlet pipe 24 of the rear evaporator Er, and the inner pipe 202 is connected to the expansion valve inlet pipe 25.

As shown in FIG. 3, the double pipe 100 has an outer pipe 101, an inner pipe 102, and a connecting rib 103 for connecting the outer pipe 101 and the inner pipe 102, which are extruded or drawn from an aluminum material. It is formed integrally by processing. The outer diameter of the outer tube 101 is about 16 to 25 mm, and the outer diameter of the inner pipe 102 is about 6 to 12 mm. Connecting rib 1
Numeral 03 is provided so as to divide a space formed between the outer tube 101 and the inner tube 102 into three parts. Connecting rib 103
Are provided, the balance with respect to triaxial bending is good, and the degree of freedom in bending design is increased. Also, the balance at the time of extrusion processing or the like is good. Since the double tube 200 is formed in the same manner, the description is omitted.

When the double pipes 100 and 200 are used for the refrigerant conduit connecting the rear evaporator Er and the cooling cycle, the refrigerant conduit for flowing the low-pressure refrigerant and the refrigerant conduit for flowing the high-pressure refrigerant are provided separately. There are the following advantages as compared with. That is, since the rigidity against bending is increased, restrictions on the bending speed and the like at the time of manufacturing are relaxed, and the productivity is improved. Since two pipes become a single conduit, the number of bending steps is reduced by half, and the processing cost is reduced. Due to the increased rigidity, deformation is less likely to occur during transportation or mounting to the vehicle body, and there is no need to fix one refrigerant conduit to the other refrigerant conduit via a bracket or the like, reducing costs and mounting to the vehicle body. Workability is also improved.

Next, the double pipe joint 5 according to the first embodiment will be described.
The configuration of 0 and 60 will be described. In addition, the double pipe joint 5
Since 0 and 60 are formed in the same manner, in the following description, the joint 50 for a double pipe will be described as an example.

As shown in FIG. 2, the double pipe joint 50 is
This is a flange-type joint, and has a main body 110 to which one end (the right end in FIG. 2) is attached to an outer tube end portion 101a where a part of the outer tube 101 and the connecting rib 103 is removed to expose the inner tube 102. The main body 110 has a pipe shape surrounding the exposed inner pipe 102, and has a passage 111 formed therein for flowing the low-pressure gaseous refrigerant flowing out of the outer pipe terminal 101a. At the other end (left end in FIG. 2) of the main body 110, a wall surface 112 through which the exposed inner tube 102 penetrates is provided. An opening 113 is provided on the peripheral surface of the main body 110, and a connection pipe 120 communicating with the passage 111 is attached to the opening 113. The main body 110 is processed by pressing or forging, and has a relatively high degree of freedom in shape.

The connecting pipe 120 has an elbow shape so as to extend in the same direction as the inner pipe 102. At an end of the connection pipe 120, a first connection portion 130 that connects the connection pipe 120 to a refrigerant conduit 37 (corresponding to a first external pipe) that guides the low-pressure gaseous refrigerant is provided. At the end of the inner pipe 102 penetrating the wall 112, a refrigerant pipe 35 (corresponding to a second outer pipe) for guiding the high-pressure liquid refrigerant is connected to the inner pipe 1
02 is provided.

The opening 113 is connected to the connecting pipe 120.
Connecting pipe 120 such as length, stretching direction, layout, etc.
Is formed at a position determined according to the arrangement state.

The wall 112 is formed by the inner pipe 102 penetrating therethrough.
Has a concave portion 112a in which a brazing material 114 (corresponding to a joining material) for joining is formed. The concave portion 112a is formed by connecting the inner peripheral edge of the center hole 112b through
It is formed by bending inward.

The connecting pipe 120 has a joint 120a joined to the edge of the opening 113 and expanded radially outward. The connection pipe 120 is
By brazing a to the edge of the opening 113, it is connected to the peripheral surface of the main body 110.

The first connecting portion 130 and the second connecting portion 140 in the illustrated example are both formed in a flange type, and are further integrally formed. A first base portion 131 brazed to an end of the connection pipe 120;
A first annular projection 132 is provided to protrude from the first base 131 and communicates with the outer pipe 101 via the connection pipe 120 and the passage 111. The second connecting part 140 includes a second base 141 that is brazed to an end of the inner pipe 102 and a second base 14 that is brazed to the end of the inner pipe 102.
1 and has a second annular projection 142 communicating with the inner tube 102. First base 131 and second base 141
Are integrated with each other to form the base 150.

A seal member such as an O-ring 133 is attached to the ring groove 132a formed in the first annular projection 132. The O-ring 133 prevents the refrigerant from leaking from the connection point with the refrigerant conduit 37. Similarly, a ring groove 142 formed in the second annular projection 142
A seal member composed of an O-ring 143 and the like is attached to “a”, and leakage of the refrigerant from a connection point with the refrigerant conduit 35 is prevented.

The base 150 has a through hole 150a through which a fastening means such as a bolt 151 or a screw is inserted. Structure 1 to which refrigerant conduits 35 and 37 are connected
By connecting bolts 151 to the flange 52 or the flange, the connection pipe 120 is connected to the refrigerant conduit 37 via the first connection part 130, and the inner pipe 102 is connected to the refrigerant conduit 35 via the second connection part 140. .

The operation will be described.

Structure 1 to which refrigerant conduits 35 and 37 are connected
When the double pipe 100 is connected to the pipe 52 or the like, first, the first annular projection 132 and the second annular projection 142 of the double pipe joint 50 are connected to the holes 152a, 152 formed in the structural body.
b. Next, if the bolt 151 is fastened, the connection of the double pipe 100 is completed.

The joint 50 for a double pipe according to the first embodiment has a main body section 110 attached to an outer pipe end section 101a where the inner pipe 102 is exposed.
At the same time, the exposed inner tube 102 is
, The outer pipe 101, the inner pipe 102, and the connecting rib 103 are applied to the integrally formed double pipe 100 to provide a suitable double pipe joint.

Further, since the connecting pipe 120 is brazed to the opening 113 of the main body 110, the opening 113 only needs to be formed at a position determined according to the arrangement state of the connecting pipe 120. And the degree of freedom in determining the layout increases. Further, even in the case of a double pipe joint in which the arrangement state of the connection pipe 120 is different, the main body 11
Since it is possible to share 0, it is possible to reduce costs through sharing of components.

The recess 112a allows the wall 112
The brazing material 114 is securely held at the joint between the inner tube 102 and the inner tube 102, and the joint between the wall surface portion 112 and the inner tube 102 after brazing becomes strong, and refrigerant leakage from the joint is reliably prevented. be able to.

Further, since the connecting portion 120a of the connecting pipe 120 is expanded radially outward, the connecting pipe 120
The passage resistance of the connection pipe 120 can be reduced without using the connection pipe 120 having an unnecessarily large inner diameter without being an obstacle for narrowing the passage in the passage 0.

FIG. 4 is a sectional view showing a modified example in which the opening of the main body is formed as a long hole. As shown, the opening 113
Is longer than the inner diameter of the connecting pipe 120 and the connecting pipe 12
It may be formed in a long hole having a size to be closed by the zero joint portion 120a. According to such a configuration, the joining portion 120
The connection pipe 12 with respect to the opening 113 within the range of the size of a
The mounting position of 0 can be adjusted. Therefore, even in the case of a double-pipe joint in which the arrangement state of the connecting pipes 120 is different, the sharing of the main body 110 can be further achieved, and the cost of parts can be further reduced. The opening 113
Is not limited to a long hole. The opening 113 only needs to be formed so that the mounting position of the connection pipe 120 with respect to the opening 113 can be adjusted. For example, the opening 113 may be formed in a round hole.

FIG. 5 is a view showing a modified example of the first and second connection portions 130 and 140 formed in a flange type. As illustrated, the ends of the inner pipe 102 and the connection pipe 120 are bent in a direction Y substantially perpendicular to a direction X in which the inner pipe 102 penetrates the wall 112.
Therefore, the through hole 150 a through which the fastening means such as the bolt 151 is inserted is formed along the direction Y different from the direction X in which the inner pipe 102 penetrates the wall surface portion 112.
According to such a configuration, in the fastening direction Y of the bolt 151,
Obstacles such as the double tube 100 and the main body 110 are not present. And, since it is easy to insert a fastening tool such as a wrench or an operator's hand, it is easy to perform fastening work of the bolt 151,
The connection work of the double pipe 100 is simplified.

Since the connecting pipe 120 is manufactured separately from the double pipe 100, the shape and the like of the connecting pipe 120 can be appropriately determined in consideration of workability at the time of connection. Therefore, at least the second connection part 140 has a through hole 150a through which the fastening means 151 is inserted, and the through hole 150a is
02 is a direction Y different from the direction X through the wall 112
What is necessary is just to be formed along.

First and second connecting portions 13 of flange type
The reference numerals 0 and 140 are not limited to the case where they are integrally formed, and may be separated flange types as shown in FIG. The first connecting portion 13 of the double pipe joint 50a
0 is the first annular projection 132 similar to that shown in FIG.
Is formed by brazing the first base portion 134 provided with the end to the end of the connection pipe 120. On the other hand, the second connection unit 140
Is a second base 144 that is swaged and fixed to the inner tube 102,
It has a connecting portion 145 connected to the refrigerant conduit 35,
The connecting portion 145 is formed integrally with the inner tube 102 by processing the inner tube terminal portion 102a itself.
The connecting portion 145 is formed with a ring groove 145a for mounting the O-ring 143 by punching or rolling the inner tube end portion 102a. Each of the first and second bases 134 and 144 has through holes 134a and 144a through which fastening means such as bolts are inserted. Since the connecting portion 145 is formed integrally with the inner tube terminal portion 102a, a separately manufactured connecting member can be used as the inner tube terminal portion 102a.
The manufacture of the joint is easier than in the case of joining to a. In addition, the inner pipe terminal part 102a is processed into a terminal, and
The configuration of 45 is also applicable to the integral flange type shown in FIG.

Further, the first connecting portion 130 and the second connecting portion 140 are not limited to the flange type,
As shown in FIG. 7, it may be configured as a union type.
In this double pipe joint 50b, a union screw 136 is attached to an end of the connection pipe 120, and the refrigerant pipe 37
The union nut (not shown) attached to the end of the connection pipe 120 is fastened, and the connection pipe 120 is connected to the refrigerant pipe 37. Also,
The union screw 146 is also attached to the inner tube terminal 102a, and a union nut (not shown) attached to the end of the refrigerant conduit 35 is fastened, and the inner tube 102 is connected to the refrigerant conduit 35. The inner tube end portion 102a has an expanded flare portion 147 fitted on the inner peripheral surface of the union screw 146. The flare section 147 is connected to the inner tube terminal section 102a.
Is formed by flare processing by punching.

As shown in FIG. 8, when the inner pipe 102 is exposed for a long time, a separate pipe 300 may be used. In the illustrated example, the tip of the pipe 300 is the inner tube terminal 1.
02a. The proximal end of the pipe 300 is
2 and the wall 112 together with the brazing material 114.

As described above, the double pipe joint 5 of the first embodiment
0, 50a, and 50b are in accordance with the mating structure of the mating side,
It can be selected from each type of integral flange, separate flange and nut union, and has a wide range of applications.

FIG. 9 is a sectional view showing a joint for a double pipe according to the second embodiment.

The double-pipe joint 50c according to the second embodiment has the inner pipe 10
2 has a main body 160 which is attached by brazing to the outer tube terminal portion 101a with the second portion exposed. The main body 160 is formed of, for example, an aluminum material. Main body 16
Reference numeral 0 denotes a block shape, in which an internal passage 1 through which the low-pressure gaseous refrigerant flowing out of the outer tube terminal portion 101a flows.
61 is formed by cutting. Internal passage 161
Is closed with a blind plug 162 brazed. The main body 160 further includes a first opening 163 communicating the refrigerant conduit 37 for guiding the low-pressure gaseous refrigerant and the internal passage 161, and a second opening 163 communicating the refrigerant conduit 35 for guiding the high-pressure liquid refrigerant and the inner pipe 102. An opening 164 is formed. The first and second openings 163 and 164 are provided in the internal passage 16.
It extends along a direction substantially perpendicular to 1 and is formed by cutting.

The inner tube 102 exposed from the outer tube terminal portion 101a extends substantially straight across the inner passage 161 and is attached to the second opening 164. The inner tube terminal portion 102a has an expanded flare portion 165 fitted to the inner peripheral surface of the second opening 164. The flare portion 165 is formed by flaring the inner tube end portion 102a by punching. Flare part 1
The 65 end is brazed to the second opening 164.

The main body 160 has a screw hole 160a for fastening a fastening means such as a bolt or a screw. Structure 16 to which refrigerant conduits 35 and 37 are connected
6 or the flange is fastened to the main body 160 by fastening means, the outer pipe 101 is connected to the refrigerant conduit 37 via the internal passage 161 and the first opening 163, and the inner pipe 102 is connected to the refrigerant via the second opening 164. Connected to conduit 35.

Even in this double pipe joint 50c, the main body 160 is attached to the outer pipe end 101a where the inner pipe 102 is exposed.
At the same time, the inner tube 102 is
, The outer pipe 101, the inner pipe 102, and the connecting rib 103 are applied to the integrally formed double pipe 100 to provide a suitable double pipe joint.

FIGS. 10 to 12 are sectional views showing modified examples of the block type main body.

In the double-pipe joint 50d shown in FIG. 10, the flare section 165 of the inner pipe end section 102a has a straight pipe shape, and a recess 170 is formed between the flare section 165 and the main body section 160. Have been. A ring-shaped brazing material 171 fitted in the flare portion 165 in advance is located in the concave portion 170. In such a configuration, the flare section 165
It is not necessary to further expand the terminal. In addition, by fitting the ring-shaped brazing material 171 into the flare portion 165 in advance, the outer tube end portion 101a and the main body portion 160 are formed.
And the brazing connection between the inner tube end portion 102a and the main body 160 can be performed simultaneously. Further, since the open end of the internal passage 161 is formed on the double pipe 100 side, three places including the brazing joint between the blind plug 162 and the main body 160 can be brazed at the same time.

In the double pipe joint 50e shown in FIG. 11, the double pipe 100 has the first
The second openings 183 and 184 are attached to the side wall 180a of the main body 180 so as to be substantially orthogonal to the axis. The outer tube terminal 101a is brazed to the side wall 180a. The distal end of the inner tube terminal portion 102a is
4 is brazed to an end of an internal passage 181 communicating with the inner passage 4. In such a configuration, since the double pipe 100 is directly attached to the open end formed on the side wall 180a for cutting the internal passage 181, it is not necessary to close the open end with a blind plug. Therefore, the number of brazing points is reduced by one,
To that extent, quality control is simplified, which is advantageous in terms of cost.

In the double pipe joint 50f shown in FIG. 12, the double pipe 100 has first and second openings 193, 194 formed in the main body 190, similarly to the joint shown in FIG.
Is attached to the side wall 190a of the main body 190 so as to be substantially perpendicular to the axis of the main body 190. The outer tube terminal 101a is brazed to the side wall 190a, and the tip of the inner tube terminal 102a is brazed to the end of the internal passage 191 communicating with the second opening 194. The first and second openings 193 in the illustrated example,
194 is formed on a convex portion having a male shape. According to such a configuration, as described above, the quality control is simplified as the number of brazing points is reduced by one, which is advantageous in terms of cost.

Next, an outline of the terminal processing of the double pipe 100 will be described.

First, as shown by the phantom line in FIG. 3, a slit 104 is formed at a position corresponding to the exposed length of the inner tube 102 from the end of the double tube until the inner tube outer peripheral surface 102a is reached. Next, the base end of the connecting rib 103 connected to the outer peripheral surface 102a of the inner pipe is cut along the axial direction from the end of the double pipe.
At this time, a cutting tool that moves along the axial direction while rotating using the inner peripheral surface 102b as a guide is used. Since the cutting tool rotates using the inner peripheral surface 102b of the inner tube as a guide, even if the position of the inner tube 102 is displaced in the radial direction, the thickness of the inner tube 102 is kept uniform and the connecting rib 103
Can be cut in the axial direction. Connecting rib 1
03 is cut to the slit 104, the outer tube 101 and the connecting rib 103 are removed from the inner tube 102, and the inner tube 1 is cut.
02 is exposed.

In the conventional processing method of cutting the outer tube 101 and the connecting rib 103 in the axial direction from the end of the double tube, a burr is formed on the outer tube end portion 101a from which a part of the outer tube 101 and the connecting rib 103 is removed. Therefore, finish processing for removing the burrs is required. On the other hand, if the slit 104 is formed in advance as in the present embodiment,
Since burrs do not occur on the outer tube terminal 101a, finishing is not required, and the working can be simplified accordingly.

Then, the exposed inner tube end portion 102a is subjected to punching or rolling to form a ring groove 1
A connecting portion 145 having 45a is formed. Alternatively, a flare process is performed by punching, and the flare portion 147,
The inner tube terminal portion 102a having the 165 is formed.

In the above conventional processing method, the inner pipe 1
When the position of 02 is shifted in the radial direction, the thickness of the exposed inner tube end portion 102a is not uniform, and when the inner tube end portion 102a is subjected to punching or the like, cracks or the like are generated. It is virtually impossible to perform punching or the like. On the other hand, the inner pipe inner peripheral surface 10
Connecting rib 103 using a cutting tool with 2b as a guide surface
Is cut, the thickness of the inner tube 102 can be made uniform, and thus, for example, punching can be performed. For this reason, the processing operation of the inner tube terminal portion 102a can be performed quickly and easily as compared with the conventional processing method.

[0060]

As described above, according to the first aspect of the present invention, it is possible to provide a suitable double pipe joint by applying the present invention to a double pipe in which the outer pipe, the inner pipe and the connecting rib are integrally formed. .
In addition, since the connection pipe is attached to the opening of the main body, it is only necessary to form the opening at a position determined according to the arrangement state of the connection pipe, so that the degree of freedom in dimension design increases and the freedom in determining the layout More often. Furthermore, even in the case of a double-pipe joint in which the arrangement of the connecting pipes is different, the main body can be shared, so that the cost can be reduced through the sharing of parts.

According to the second aspect of the present invention, since the inner tube has a connecting portion formed integrally with the inner tube by processing the end portion, the separately manufactured connecting member can be connected to the inner tube terminal. As compared with the case of joining to the joint, the manufacture of the joint is facilitated.

According to the third aspect of the present invention, the joining material is securely held at the joint between the wall surface portion and the inner tube by the concave portion, and the joint between the wall surface portion and the inner tube after joining is strong. Thus, refrigerant leakage from the joint can be reliably prevented.

According to the fourth aspect of the invention, the passage in the connecting pipe is not narrowed, and the passage resistance of the connecting pipe can be reduced without using a connecting pipe having an inner diameter larger than necessary. .

According to the fifth aspect of the present invention, the mounting position of the connection pipe with respect to the opening can be adjusted within the range of the size of the joint portion, and the main body can be further shared, and parts can be further improved. Further cost reductions can be achieved.

According to the invention as set forth in claim 6 or 7, according to the mating structure of the mating side, it is possible to select from the types of integral flange, separation flange, and nut union, and to apply a double It becomes a pipe joint.

According to the eighth aspect of the present invention, there is no obstacle such as the double pipe or the main body in the fastening direction of the fastening means, so that it is easy to insert a fastening tool such as a spanner or a hand of an operator. In addition, the fastening work becomes easier and the connection work of the double pipe becomes easier.

According to the ninth aspect, the outer tube,
A suitable double pipe joint can be provided by applying the present invention to a double pipe in which the inner pipe and the connecting rib are integrally formed.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating an air conditioner for a vehicle according to an embodiment to which a double pipe joint according to the present invention is applied.

FIG. 2 is a cross-sectional view illustrating the double pipe joint according to the first embodiment.

FIG. 3 is a perspective view showing a double pipe.

FIG. 4 is a cross-sectional view showing a modified example in which the opening of the main body is formed as a long hole.

FIG. 5 is a view showing a modified example of the first and second connecting portions configured as a flange type.

FIG. 6 is a cross-sectional view showing a modified example in which the first and second connection portions are configured as a separated flange type.

FIG. 7 is a cross-sectional view showing a modified example in which the first and second connection portions are configured as a union type.

FIG. 8 is a cross-sectional view showing a modification in which a separate pipe is used when the inner pipe is exposed for a long time.

FIG. 9 is a cross-sectional view showing a double pipe joint according to a second embodiment.

FIG. 10 is a sectional view showing a modification of the block-type main body.

FIG. 11 is a sectional view showing another modification of the block-type main body.

FIG. 12 is a sectional view showing still another modification of the block-type main body.

[Explanation of symbols]

 35: refrigerant pipe (second outer pipe) 37: refrigerant pipe (first outer pipe) 50, 60: double pipe joint 100: double pipe 101: outer pipe 101a: outer pipe terminal 102: inner pipe 102a: inside Tube end 103 103 Connecting rib 110 Main body 111 Passage 112 Wall 112 a Depressed 113 113 Opening 114 Brazing material (joining material) 120 Connecting pipe 120 a Joining 130 130 First connecting part 140 Second Connection part 145 Connection part 151 Bolt (fastening means) 150a Through hole 160, 180, 190 Block main body part 161, 181, 191 Internal passage 162 Blind plug 163, 183, 193 First opening 164 , 184, 194... Second opening

Claims (9)

[Claims] An outer tube (101) through which a first fluid flows, and the outer tube (101)
A double pipe (100) in which an inner pipe (102) provided inside the (101) and through which a second fluid flows and a connecting rib (103) connecting the two pipes are integrally formed by extrusion or drawing. In the double pipe joint used to connect the outer pipe (101), one end is attached to an outer pipe end portion (101a) in which a part of the outer pipe (101) is removed to expose the inner pipe (102). A main body (110) surrounding the inner pipe (102) and a passage (111) through which the first fluid flows, and provided at the other end of the main body (110), A wall portion (112) through which the inner pipe (102) penetrates; an opening (113) provided in the main body (110); and a connection pipe (attached to the opening (113) and communicating with the passage (111)). A first connection part (130) provided at an end of the connection pipe (120) and connecting the connection pipe (120) to a first external pipe (37) for guiding the first fluid; The inner pipe (10 The inner pipe is provided at a second outer pipe (35) which is provided at an end of the second pipe and guides the second fluid.
(102), and the opening (113) is formed at a position determined according to the arrangement state of the connection pipe (120), and the main body (110) is Double pipe joint characterized by being shared. 2. The second connecting part (140) is connected to the inner pipe (102).
The end portion (102a) of the inner tube (10
The joint for a double pipe according to claim 1, further comprising a connecting portion (145) formed integrally with the second outer pipe and connected to the second outer pipe (35). 3. The inner pipe penetrating the wall portion (112).
The joint for a double pipe according to claim 1, further comprising a concave portion (112a) in which a joining material (114) for joining the (102) is held. 4. The connecting pipe (120) has a joint (120a) joined to an edge of the opening (113) and expanded radially outward. 2. The double-pipe joint according to 1. 5. The double-pipe joint according to claim 4, wherein the opening (113) is formed so that a mounting position of the connection pipe (120) with respect to the opening (113) can be adjusted. . 6. The first connection part (130) and the second connection part.
The joint for a double pipe according to claim 1, wherein the (140) is configured as a flange type or a union type. 7. The first connection part (130) of the flange type.
The joint for a double pipe according to claim 6, wherein the second connecting portion (140) of the flange type is integrally formed. 8. The second connecting portion (140) configured as a flange type has a through hole (150a) through which a fastening means (151) is inserted, and the through hole (150a) is connected to the inner pipe (150). The joint for a double pipe according to claim 6 or 7, wherein the (102) is formed along a direction (Y) different from a direction (X) penetrating the wall portion (112). 9. An outer tube (101) through which a first fluid flows, and said outer tube
A double pipe (100) in which an inner pipe (102) provided inside the (101) and through which a second fluid flows and a connecting rib (103) connecting the two pipes are integrally formed by extrusion or drawing. ), A part of the outer pipe (101) is removed, the inner pipe (102) is exposed to the outer pipe end (101a), and the first pipe is connected to the first pipe joint. A block-shaped main body (16) having an internal passage (161) for flowing fluid
0), a first external pipe (37) formed in the main body (160) for guiding the first fluid and communicating with the internal passage (161).
An opening (163), a second opening formed in the main body (160) and communicating the second outer pipe (35) for guiding the second fluid and the inner pipe (102);
(164), wherein the inner tube (102) exposed from the outer tube terminal portion (101a) extends substantially straight across the inner passage (161). Pipe fittings.