JP2002013896A - Heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat exchanger having a joint efficiently provided at a tank. SOLUTION: The heat exchanger comprises the tank 200 having the joint 210 provided to introduce or discharge a medium, and a tube 300 coupled to the tank in such a manner that heat exchanging of the medium is conducted by a heat to be transferred to the tube. The tank is made of a tubular member closed at both ends, the joint has a tubular pipe 211 inserted into and brazed to the tank, an outer diameter LA of the pipe is larger than an inner diameter LB of the tank, and a distal end 211a of the pipe is formed thinner than the other site of the pipe and projected into the tank. The exchanger is a radiator of a refrigerating cycle, and its internal pressure exceeds a critical point of the medium.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger including a tank provided with a joint for flowing in or out of a medium, and a tube connected to the tank, and performing heat exchange of the medium by heat transmitted to the tube. .

[0002]

2. Description of the Related Art Generally, a heat exchanger is known in which a plurality of flat tubes are connected to a tubular tank and heat exchange of a medium is performed by heat transmitted to the tubes. This type of heat exchanger is used, for example, as a radiator of an automobile or a radiator of a refrigeration cycle.

[0003] Further, a pair of joints for connecting external pipes are provided at key points of the tank, and the medium flows in from one joint and flows through the tube while performing heat exchange. From the other joint. The tank is constituted by a tubular member having both ends closed. The joint has a pipe inserted and brazed into the tank. Such a configuration of the joint portion is also disclosed, for example, in Japanese Patent Application Laid-Open No. 6-229696.

[0004]

In recent years, a refrigerating cycle using CO ₂ as a medium (that is, a refrigerant) has been used, and the pressure inside the radiator varies depending on the use conditions such as air temperature. The configuration is above the critical point. In particular, when the pressure exceeds the critical point of the medium inside the radiator, the medium is not condensed. Note that a refrigeration cycle using CO ₂ as a medium is described in, for example, JP-A-11-94.
No. 380 and Japanese Patent Application Laid-Open No. 11-226684.

A radiator whose internal pressure exceeds the critical point of the medium as described above requires extremely high pressure resistance.

[0006] In the case of a heat exchanger requiring high pressure resistance, the members constituting the tank must be sufficiently thick and relatively small in diameter in order to ensure the required pressure resistance. Not get. In this regard, the joint portion has a problem that the diameter of the pipe portion is relatively large with respect to the diameter of the tank, which makes it difficult to insert and braze the pipe portion into the tank.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a heat exchanger in which a joint is efficiently provided in a tank.

[0008]

According to the first aspect of the present invention, there is provided a tank provided with a joint for flowing in or out of a medium, and a tube connected to the tank. In a heat exchanger for exchanging heat of the medium, the tank is formed of a tubular member having both ends closed, and the joint portion includes a tubular pipe portion inserted and brazed into the tank, The outer diameter of the portion is larger than the inner diameter of the tank, and the tip of the pipe portion is formed narrower than the other portion of the pipe, and is a heat exchanger configured to protrude into the tank. According to such a configuration, the joint portion is efficiently provided in the tank.

[0009] That is, with respect to the joint portion provided in the tank, if the outer diameter of the pipe portion is larger than the inner diameter of the tank, there is a disadvantage that insertion and brazing to the tank become difficult. Such an inconvenience is avoided because the tip of the part is formed slender and protrudes into the tank.

In particular, according to the brazing, since the brazing material accumulates in the form of a fillet between the tip of the pipe portion and the inner surface of the tank, the strength and airtightness of the brazing portion are surely improved.

According to a second aspect of the present invention, in the first aspect, the orthographic projection of the tip of the pipe portion with respect to the longitudinal direction of the tank is a heat exchanger having a curved configuration. According to the configuration, the flow path resistance of the medium is reduced.

That is, if the tip of the pipe protrudes into the tank, this may cause an increase in the flow resistance of the medium, but in the present invention, the medium is transferred from the pipe to the inside of the tank or Such an inconvenience is avoided because the fluid flows smoothly from the inside to the pipe portion.

According to a third aspect of the present invention, in the first or second aspect, the heat exchanger is a radiator of a refrigeration cycle, and an internal pressure exceeds a critical point of the medium. Heat exchanger. The radiator cools the medium.

Here, the critical point is a limit on a high temperature side (that is, a limit on a high pressure side) where a gas layer and a liquid layer coexist.
One end of the vapor pressure curve. The pressure, temperature, and density at the critical point are the critical pressure, critical temperature, and critical density, respectively. If the pressure exceeds the critical point of the medium inside the radiator, the medium will not condense.

That is, the present heat exchanger is provided with a joint portion in which the outer diameter of the pipe portion is larger than the inner diameter of the tank, and is suitable as a radiator in which the internal pressure exceeds the critical point of the medium. Used for

[0016]

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

The heat exchanger 1 of the present embodiment shown in FIG. 1 is a radiator used for a refrigeration cycle for cooling the interior of an automobile.
CO ₂ is used as the medium, and the pressure inside the heat exchanger 1 exceeds the critical point of the medium depending on the use conditions such as the temperature.

The heat exchanger 1 is configured such that tubes 300 and fins 400 are alternately stacked in parallel and each tube 300 is connected to a pair of tanks 200.

A side plate 500 as a reinforcing member is provided on the layer composed of the tubes 300 and the fins 400.

One of the tanks 200 is provided with a joint 210 for flowing the medium from the compressor of the refrigeration cycle, and the other tank 200 is provided with a joint 210 for flowing the medium to the pressure reducer of the refrigeration cycle. Is provided.

The medium is supplied to the joint 21 of one tank 200.
0 and the fin 4
Tube 300 while performing heat exchange by heat transmitted to
After flowing through the joint portion 210 of the other tank 200 to the outside. The white arrows in FIG. 1 indicate the flow direction of the medium.

Each tank 200 is composed of a tubular extruded member having both ends closed by caps, and each tube 300
Is a flat shape having a plurality of small flow paths.

Each tube 300 is connected by inserting one end into one tank 200 and inserting the other end into the other tank 200. Each tank 200 is provided with holes for inserting the ends of the tubes 300 at a predetermined pitch in the longitudinal direction.

Further, each joint part 210 is formed by inserting a pipe part 211 at a key point of the tank 200. A hole of a predetermined shape into which the pipe portion 211 is inserted is provided at a key point of the tank 200. In particular, in this example, in consideration of the smooth flow of the medium, the joint 210 for inflowing the medium is provided substantially at the center of one of the tanks 200, and the outflow 210 for the medium is provided near the lower end of the other tank 200. Provided.

The pipe portion 211 is a tubular portion for introducing the flow path of the medium into the inside of the tank 200, and in this embodiment, is constituted by a drawing tube.

At the base end of the pipe portion 211 located outside the tank 200, a block for connecting an external pipe is provided. The external piping connects the heat exchanger 1 and the compressor, or connects the heat exchanger 1 and the decompressor.

Then, the tank 200, the joint part 210, the tube 300, the fin 400, and the side plate 50
No. 0 is obtained by assembling the members constituting these components, and heat-treating this assembled body in a furnace to braze it to form an integral body. The brazing material is provided by cladding each member in advance.
In addition, the solder may be appropriately placed at a location.

FIGS. 1 and 2 are a perspective view and a sectional view, respectively, showing the essential parts of the tank 200. As shown in these figures,
Joint 210 of the present embodiment, the outer diameter _{L A} of the pipe 211 parts is larger than the inside diameter _{L B} of the tank 200.

The pipe portion 211 has a taper whose wall thickness decreases toward its tip 211a.
Of the pipe 20 due to this taper.
0 is thinner than other parts. Pipe section 21
The inner diameter of 1 is constant in the longitudinal direction. The tip 211 a of the pipe 211 protrudes into the tank 200.

Positioning when inserting the pipe portion 211 into the tank 200 is performed by pressing a taper against a hole of the tank 200.

According to the brazing, the brazing material R accumulates in a fillet shape between the tip end 211a of the pipe portion 211 and the inner surface of the tank 200.

As described above, according to the heat exchanger of this embodiment,
The tank is formed of a tubular member closed at both ends, and the joint portion includes a tubular pipe portion inserted and brazed into the tank, the outer diameter of the pipe portion is larger than the inner diameter of the tank, and Since the tip is formed thinner than the other part of the pipe and protrudes into the tank, the tank can be provided with a joint portion efficiently.

That is, with respect to the joint portion provided in the tank, if the outer diameter of the pipe portion is larger than the inner diameter of the tank, there is a disadvantage that it becomes difficult to insert and braze the tank portion. Such an inconvenience can be avoided because the tip of the portion is formed slender and protrudes into the tank.

In particular, according to the brazing, since the brazing material accumulates in the form of a fillet between the tip of the pipe portion and the inner surface of the tank, the strength and airtightness of the brazing portion can be surely improved. it can.

Further, the heat exchanger is a radiator of a refrigeration cycle, and the internal pressure exceeds the critical point of the medium. That is, the present heat exchanger is one in which a joint part in which the outer diameter of the pipe part is larger than the inner diameter of the tank is efficiently provided, and is preferably used as a radiator in which the internal pressure exceeds the critical point of the medium. be able to.

Next, a second embodiment of the present invention will be described with reference to FIG. In the specific example described above, the distal end 211a of the pipe portion 211 is formed to be narrow by a taper, but in this example, it is formed to be narrow by a steep step.
Since other basic configurations are the same as those of the above-described specific example, common members are denoted by the same reference numerals, and description thereof is omitted.

As described above, the end 21 of the pipe portion 211
1a may be formed slenderly by such a step.

Next, a third embodiment of the present invention will be described with reference to FIG. In the case of this example, the tip 211 of the pipe portion 211
With respect to a, the orthogonal projection of the tank 200 in the longitudinal direction is curved. Other basic configurations are
Since it is the same as the above-described specific example, the common members are denoted by the same reference numerals, and the description thereof is omitted.

According to the heat exchanger of this embodiment, since the orthogonal projection of the tip of the pipe portion in the longitudinal direction of the tank exhibits a curve, the flow resistance of the medium can be reduced.

That is, if the tip of the pipe protrudes into the tank, this may cause an increase in the flow resistance of the medium, but in this example, the medium flows from the pipe into the tank or into the tank. Since the fluid flows smoothly from the inside to the pipe portion, such inconvenience can be avoided.

Next, a fourth embodiment of the present invention will be described with reference to FIG. The joint part 210 of this example is a block body formed by cutting a forged member and mounted on the outer peripheral surface of the tank 200. Since other basic configurations are the same as those of the above-described specific example, common members are denoted by the same reference numerals, and description thereof is omitted.

The external pipe 600 is provided with a block 610 corresponding to the joint 210, and the joint 210 and the block 610 are screwed using a plurality of screw bodies 620. The joint 210 and the block 610 are provided with a through hole 611 through which the screw body 620 is inserted and a screw hole 213 into which the screw body 620 is screwed.

An O-ring 630 for ensuring the airtightness of the medium is interposed between the opening 212 of the joint 210 and the external pipe 600.

As described above, the joint 210 may be a block attached to the outer peripheral surface of the tank. According to such a configuration, the supporting strength of the joint 210 can be further improved, and the structure of the joint 210 can be simplified.

[0045]

According to the first aspect of the present invention, there is provided a tank provided with a joint for flowing in or out of a medium, and a tube connected to the tank. In a heat exchanger that performs heat exchange, the tank is formed of a tubular member having both ends closed, and the joint portion includes a tubular pipe portion inserted and brazed into the tank, and an outer diameter of the pipe portion. Is a heat exchanger having a configuration that is larger than the inner diameter of the tank, and the tip of the pipe portion is formed narrower than other parts of the pipe, and protrudes into the tank. According to the configuration, the joint portion can be efficiently provided in the tank.

According to a second aspect of the present invention, in the heat exchanger according to the first aspect, an orthographic projection of the tip of the pipe portion in the longitudinal direction of the tank exhibits a curve. According to such a configuration, the flow path resistance of the medium can be reduced.

According to a third aspect of the present invention, in the first or second aspect, the heat exchanger is a radiator of a refrigeration cycle, and an internal pressure exceeds a critical point of the medium. Heat exchanger. That is, the present heat exchanger is one in which a joint part in which the outer diameter of the pipe part is larger than the inner diameter of the tank is efficiently provided, and is preferably used as a radiator in which the internal pressure exceeds the critical point of the medium. be able to.

[Brief description of the drawings]

FIG. 1 is a front view showing a heat exchanger according to a specific example of the present invention.

FIG. 2 is a perspective view showing a main part of a tank according to a specific example of the present invention.

FIG. 3 is a cross-sectional view illustrating a main part of a tank according to a specific example of the present invention.

FIG. 4 is a cross-sectional view showing a main part of a tank according to a specific example of the present invention.

FIG. 5 is a cross-sectional view showing a main part of a tank according to a specific example of the present invention.

FIG. 6 is a cross-sectional view showing a main part of a tank and external piping according to a specific example of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Heat exchanger 200 Tank 210 Joint part 211 Pipe part 211a Tip 212 Opening 213 Screw hole 300 Tube 400 Fin 500 Side plate 600 External piping 610 Block 611 Through hole 620 Threaded body 630 O-ring LA Outer diameter of _A pipe L Inside diameter of _B tank R Brazing material

Claims (3)

[Claims] 1. A tank provided with a joint part for flowing in or out of a medium, and a tube connected to the tank,
In a heat exchanger that performs heat exchange of the medium by heat transmitted to the tube, the tank is formed of a tubular member having both ends closed, and the joint portion is a tubular pipe portion inserted and brazed into the tank. The outer diameter of the pipe portion is larger than the inner diameter of the tank, and the tip of the pipe portion is formed thinner than other parts of the pipe, and protrudes into the tank. Characterized heat exchanger. 2. The heat exchanger according to claim 1, wherein an orthographic projection of the tip of the pipe portion in a longitudinal direction of the tank exhibits a curve. 3. The heat exchanger according to claim 1, wherein the heat exchanger is a radiator of a refrigeration cycle, and an internal pressure is higher than a critical point of the medium.