JP2008196319A - Tube support structure of heat exchanger for EGR cooler - Google Patents

Abstract

[PROBLEMS] To prevent cracks due to the amplitude of a flat tube affected by vibrations of an engine or the like by suppressing the movement of each flat tube, and deformation of the flat tube due to heat when brazing the flat tube to an end plate. It is an object of the present invention to provide a tube support structure for a heat exchanger for an EGR cooler in which the cooling water easily flows in the core.
A metal elongated coil or elongated thin wire formed into a roughly coiled coil spring shape is formed between the inner wall surface of the shell of the heat exchanger and the outer flat surfaces of both flat tubes located on the outermost side of the tube assembly. A corrugated plate formed by bending a plate material into a wave shape is interposed as a tube support member, and the longitudinal direction of the tube support member is provided in a direction crossing the flow of the cooling water, and the cooling water in the heat exchanger is provided. Is configured to prevent stagnation of cooling water by passing between the roughly wound wire rods of the tube support member or the corrugated side surface of the corrugated plate.
[Selection] Figure 1

Description

  The present invention relates to a tube support structure in a heat exchanger for an EGR cooler having a tube support member formed in a shape in which it is difficult to inhibit the flow of cooling water in the heat exchanger for an EGR cooler having a plurality of flat tubes.

The tube assembly of a heat exchanger for an EGR cooler having a conventional flat tube overlaps the dowels of flat tubes having a plurality of convex dowels arranged on the surface, and the end plate while maintaining the clearance between the flat tubes However, when the tube assembly is assembled to the shell, there is no convex dowel on the shell side, so the clearance between the outermost two flat tubes and the shell is increased, and the tube assembly is attached to the shell. It will be in the state which is not restrained.
Therefore, in a tube support structure (hereinafter simply referred to as a tube support structure) of a heat exchanger for an EGR cooler having a conventional flat tube, teeth 1a of a baffle plate 1 formed in a comb shape as shown in FIGS. A large number of flat tubes 2,..., 2 are arranged at equal intervals so that the flat tube 2 is sandwiched between the teeth 1a, and both ends of the arranged flat tubes 2,. In order to increase the cooling effect by causing the plate 1 to meander the flow of the cooling water to make the flow of the cooling water meander (Patent Documents 1, 2, and 3). And the crack by the amplitude of the flat tube 2 which the vibration of an engine etc. exerts on this baffle plate 1 or the flat tube 2 by the heat | fever at the time of assembling | attaching each flat tube 2, ..., 2 to the end plates 4 and 4 and brazing. Deformation was prevented.

JP 11-013549 A JP 2002-107091 A JP 2004-177060 A

[Problems of the prior art]
In the tube support structure having such a configuration, the flat tubes 2,..., 2 are sandwiched by the comb-shaped baffle plate 1 to suppress the movement of the flat tubes 2,. In addition, it was possible to prevent the deformation of the flat tube 2 due to heat when the flat tubes 2, 2, 2 are assembled to the end plates 4, 4 and brazed, but the cooling water is supplied from the cooling water inlet 5. By flowing into the shell 3 and flowing through a flow path in which a large meandering path is formed by the baffle plates 1,... 1 and discharging from the cooling water outlet 6, it becomes a factor that hinders the flow of cooling water for heat exchange. However, the flow of cooling water is not smooth, and stagnation of the cooling water occurs around the support part of the baffle plate 1, and the heat exchange performance is not satisfactory, and the heat exchange performance is boiled. It has been a concern.

  The present invention has been made in view of the above-mentioned problems in the prior art, and the technical problem specifically set in order to solve this problem is to suppress the movement of each flat tube and to vibrate the engine etc. EGR cooler heat that prevents cracks due to the amplitude of the flat tubes exerted by the tube and deformation of the flat tubes due to heat when brazing each flat tube to the end plate and makes it easier for cooling water to flow through the core It is to provide a tube support structure for an exchanger.

In order to specify an EGR cooler having an air vent structure that effectively solves the above-described problems in the present invention, all the matters recognized as necessary are covered and specifically configured as the problem solving means.
A first problem-solving means related to a tube support structure of an EGR cooler heat exchanger is an EGR cooler heat exchanger in which a shell assembly in which a plurality of flat tubes are stacked is built in a shell. Between the wall surface and the outer flat surfaces of both flat tubes located on the outermost side of the tube assembly, a metal elongated coil formed in the shape of a coarsely wound coil spring is interposed as a tube support member. A longitudinal direction of the member is provided in a direction crossing the flow of the cooling water, and the cooling water in the heat exchanger passes between the roughly wound wires of the tube support member to prevent the cooling water from staying. It is characterized by doing.

  The second problem-solving means related to the tube support structure of the EGR cooler heat exchanger is the same as that of the EGR cooler heat exchanger in which a shell assembly in which a plurality of flat tubes are stacked is built in the shell. Between the inner wall surface and the outer flat surfaces of both flat tubes located on the outermost side of the tube assembly, a corrugated plate formed by bending a thin thin plate material into a wave shape is interposed as a tube support member, and this tube support Both the longitudinal direction of the member and its wavy side face are provided in the direction intersecting the flow of the cooling water, and the cooling water in the heat exchanger passes through the wavy side face of the tube support member to prevent the cooling water from staying. It is characterized by doing.

  The third problem-solving means related to the tube support structure of the heat exchanger for EGR cooler is the same as that described above, and at least one of the tube support members is disposed between at least one of the shell of the heat exchanger and the flat tubes. It is characterized by that.

  The fourth problem-solving means according to the tube support structure of the EGR cooler heat exchanger is characterized in that one or more tube support members are arranged between the stacked flat tubes.

  Further, the fifth problem-solving means according to the tube support structure of the EGR cooler heat exchanger is provided with a plurality of tube support members having a length shorter than the flat width of the flat tube as the tube support member. Features.

  In the first problem solving means according to the tube support structure of the heat exchanger for the EGR cooler, the cooling water in the heat exchanger passes between the roughly wound wires of the tube support member to prevent the cooling water from staying. The cooling water can be prevented from boiling from the tube, and the tube support member can be bent when a load is applied to prevent stress concentration, preventing cracks in the flat tube caused by vibrations from the engine, etc. Even if the tube is integrally brazed to the end plate, the tube support member can flexibly cope with deformation of the flat tube, and deformation of the flat tube due to heat can be prevented.

  In the second problem solving means related to the tube support structure of the heat exchanger for EGR cooler, the cooling water in the heat exchanger passes through the waved side surface of the tube support member to prevent the cooling water from staying, and the cooling water boils. Can be prevented, and stress concentration can be prevented by bending the corrugated plate surface when a load is applied, and it is flexible against the deformation and cracking of flat tubes caused by vibrations and heat of engines etc. And deformation of the flat tube can be prevented.

  In the third problem solving means relating to the tube support structure of the heat exchanger for the EGR cooler, the tube support members can be attached by various arrangement methods such as changing the number or the installation position, and depending on the applied load. Due to the buffering action that causes the tube support member to be deformed to release the force, it is possible to prevent the flat tube from being cracked by vibrations of the engine or the like, and to prevent the flat tube from being deformed by heat.

  In the fourth problem solving means according to the tube support structure of the heat exchanger for EGR cooler, the tube support member is deformed with respect to the load by adding the tube support member between the laminated flat tubes. The occurrence of cracks in the flat tube caused by vibration of the engine or the like can be prevented, and deformation of the flat tube due to heat can also be prevented.

  Further, in the fifth problem solving means relating to the tube support structure of the heat exchanger for the EGR cooler, a plurality of tube support members having a length shorter than the width of the flat surface of the flat tube are provided as the tube support member. The water becomes easier to flow in the heat exchanger, and the buffering action of the tube support member is more effectively exhibited, preventing the cooling water from staying and preventing the cooling water from boiling, and the flat tube It is possible to prevent cracking and deformation.

Hereinafter, the best embodiment according to the present invention will be described in detail.
However, this embodiment is specifically described for better understanding of the gist of the invention, and does not limit the content of the invention unless otherwise specified.
The same components as those described in the prior art are denoted by the same reference numerals, and a specific description thereof is omitted.

  The heat exchanger for an EGR cooler in this embodiment has a stainless steel (heat exchanger) main body 10 as shown in FIGS. 1 to 4, and the main tube 10 is a flat tube 2 incorporated in a tube assembly 11. .., 2 are introduced into the EGR gas, and cooling water is introduced from the cooling water inlet 5 provided at the lower part of one end of the shell 3, and passes along the outer surfaces of the flat tubes 2,. Then, the EGR gas is cooled through the outer surface of each of the flat tubes 2,..., 2, and the cooling water is discharged from the cooling water outlet 6 provided at the upper part on the other end side of the shell 3. Can be lowered.

〔Constitution〕
Inside the main body 10, a metal wire is formed at a substantially central portion of the wide flat surfaces 2 a, 2 a of the flat tubes 2, 2 located on the outermost side of the tube assembly 11 in which a large number of flat tubes 2, 2 are bundled. The tube support members 12 and 12 formed into a long and thin coil spring-shaped coil or the tube support members 13 and 13 formed into a corrugated plate by bending a long and thin thin plate material into a corrugated or bellows shape are used as the shell 3 and the flat tube of the heat exchanger. 2 so that there is no gap between them. In assembling, the length of the tube support member 12 or 13 is determined according to the width of the wide flat surface 2a, 2a of the flat tube 2 regardless of the presence or absence of the dowel, and attached to a predetermined position.
The tube support member 12 is formed by roughly winding a metal wire having the same diameter into a long coil spring-shaped coil.
The corrugated tube support member 13 is a thin corrugated sheet material that is formed into a corrugated or bellows shape by reversing the belt-shaped material of the same thickness by 180 degrees and bending them in the opposite direction in order.

Inside the main body 10, a tube assembly 11 in which a large number of flat tubes 2, 2, 2 are supported at both ends by substantially equal intervals by end plates 4, 4 is accommodated. And the inside of the shell 3 is partitioned so that cooling water can be passed through the outer surface side of each of the flat tubes 2,... 2, and an EGR gas passage is formed inside the flat tube 2.
A cooling water inlet 5 and a cooling water outlet 6 are connected to the space between the end plates 4 and 4 in the shell 3, and the cooling water flowing into the shell 3 from the cooling water inlet 5 is caused to flow by the tube assembly 11. Each of the flat tubes 2,..., 2 accommodated in the main body 10 through the formed space is cooled from the outer surface side, and the EGR gas flowing inside each flat tube 2,. Thus, the temperature of the EGR gas is lowered.

[Support member mounting method]
Hereinafter, the case of a metal wire coil as the tube support member will be described, but the same applies to the case of the corrugated tube support member 13.
(1) When providing one each in the flat tube located in the outermost surface side As shown in FIG. 3, each flat tube 2, ..., 2 of the tube assembly 11 is a large number provided in the wide plane 2a, 2a. The dowels 14,..., 14 are abutted and bundled so that the flat tubes 2,..., 2 are bundled at equal intervals, and the dowels 14 on the outer surface of the flat tubes 2, 2 located on the outermost side. .., 14 are arranged at positions where the tube support member 12 having the same length as the width of the wide plane is arranged with the longitudinal direction of the tube support member 12 facing the width direction of the plane, To fix.

(2) When one is provided on one side and two are provided on the other side, as shown in FIG. 5, a number of dowels 14 provided on the wide flat surfaces 2a, 2a of the flat tubes 2,. , ... are bundled at equal intervals by the flat tubes 2, ..., 2, and the dowels 14, ..., 14 are arranged on the outer surface of one of the flat tubes 2, 2 located on the outermost side. And the dowels 14 at positions corresponding to 1/3 of the length of the tube assembly 11 from the end plates 4 and 4 on the surface located outside the other flat tube 2. The tube support members 12 and 12 having the same length as the widths of the wide planes 2a and 2a are respectively disposed at positions where the ... 14 are not provided, and the planes 2a and 2a having a wide longitudinal direction of the tube support member 12 are provided. Placed in the width direction of Securing the contact of each other.

(3) When two each are provided in the flat tube located in the outermost surface side As shown in FIG. 6, many dowels provided in the wide plane 2a, 2a of each flat tube 2, ..., 2 of the tube assembly 11 The flat tubes 2, 2 are bundled at equal intervals by 14,.., 14, and the dowels 14,. And a position corresponding to one-third of the length of the tube assembly 11 from the outer end plates 4 and 4 (locations that uniformly support the end plates 4 and 4) The tube support members 12,..., 12 having the same length as the widths of the wide flat surfaces 2a, 2a of the flat tubes 2, 2 are respectively connected to the long flat surfaces 2a, 2a in the longitudinal direction of the tube support member 12. To the width direction And location, to secure the contact of each other.

(4) When provided between flat tubes As shown in FIG. 7, on the outer surface side of the flat tubes 2, 2 positioned on the outermost surface side of the flat tubes 2,. In addition to providing the tube support member 12 having the same length as the width of the wide flat surfaces 2a, 2a of the flat tubes 2, 2 on the wide flat surfaces 2a, 2a, the flat tubes 15, ..., 15 having no dowels are bundled together. Between the flat tubes 15,..., 15 of the tube assembly 16 to be formed, the longitudinal direction of each flat tube 15,..., 15 is set such that the longitudinal direction of the tube support member 12 is directed in the width direction of the wide flat surfaces 2a, 2a. It is inserted so as to be sandwiched between the central portions, and the contact portions are fixed.

(5) When providing the tube support member 12 shorter than the width of the wide flat surface of the flat tube As shown in FIG. 8, the flat tube located at the outermost position among the flat tubes 2,. The tube support member 17 having a length shorter than the width of the wide planes 2a and 2a positioned on the outer planes 2 and 2 is evenly distributed between the end plates 4 and 4 of the tube assembly 11. A plurality of supporting positions are arranged side by side in the coaxial direction, and the respective contact positions are fixed.
Among these, even if the number of the tube support members 12 or 17 of (3) and (5) is larger than the number described in (3) and (5), the tube support members 12 or 17 should be disposed in the same manner. Thus, a larger number of tube support members 12 or 17 can be arranged.

[Function and effect]
In such a tube support structure of the heat exchanger for an EGR cooler, when the tube support members 12, 13 or the short tube support member 17 is provided on the wide side plane, at least the outermost part of the tube assembly 11 is used. Are provided on the outer plane of the flat tubes 2, 2, so that the projected cross-sectional area of the tube support members 12, 13 or the short tube support member 17 with respect to the flow of cooling water flowing in the heat exchanger Becomes very small, and the cooling water that flows outside the flat tubes 2,..., 2 flows smoothly to prevent stagnation of the cooling water and avoids boiling locally. Thus, good heat exchange performance can be obtained, and the bending of the tube support members 12, 13 or the short tube support member 17 can be obtained. It is possible to suppress the deformation of the flat tubes 2, 2 side under a load of the tube more coming from the vibration of the engine.

In addition to the support member mounting method (1), according to the support member mounting methods (2) to (5), the EGR cooler mounting state, the length and size of the heat exchanger for the EGR cooler, the tube width, Appropriate tube support members 12, 13 or short tube support members 17 can be used according to the tube interval, and cracks in the flat tube due to engine vibrations can be prevented by devising usage. can do.
Furthermore, when using such a heat exchanger, the flat tube 2 is used in the vertical direction in consideration of air bleed. However, when brazing, the flat tube 2 is laid down in a furnace and stacked. Since many pieces are heated, the tube support members 12, 13 can prevent the flat tubes 2, ..., 2 from drooping when brazed together. For this reason, only when the heat exchanger for the EGR cooler is used. In addition, deformation of the tube due to heat during brazing can also be prevented.

It is a perspective view at the time of seeing the tube support structure of the heat exchanger for EGR coolers which concerns on the embodiment of this invention from diagonally downward. It is an enlarged side view of the A section in FIG. It is a perspective view which shows the attachment state (attachment method (1)) of the tube support member in the embodiment of this invention. It is a perspective view which shows the example of the tube support member in the embodiment of this invention, (A) is a tube support member of a helical metal wire, (B) is a tube support member of a corrugated sheet. It is a perspective view which shows the attachment state (attachment method (2)) of the tube support member in the embodiment of this invention. It is a perspective view which shows the attachment state (attachment method (3)) of the tube support member in the embodiment of this invention. It is a perspective view which shows the attachment state (attachment method (4)) of the tube support member in the embodiment of this invention. It is a perspective view which shows the attachment state (attachment method (5)) of the tube support member in the embodiment of this invention. It is perspective explanatory drawing which shows the attachment method of the baffle plate in the tube support structure of the conventional heat exchanger for EGR coolers. It is side surface explanatory drawing which shows the flow of the cooling water in the tube support structure of the conventional heat exchanger for EGR coolers.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Baffle plate 1a Teeth 2 Flat tube 2a (Wide) plane 3 Shell 4 End plate 5 Cooling water inlet 6 Cooling water outlet 10 Main body 11 (of EGR heat exchanger) Tube assembly 12 (Coil-shaped) tube support member 13 (Corrugated) tube support member 14 dowel 15 flat tube 16 without dowel (formed by bundling flat tubes without dowel) tube assembly 17 (short length) tube support member

Claims (5)

  In a heat exchanger for an EGR cooler in which a tube assembly in which a plurality of flat tubes are stacked is incorporated in a shell, the inner wall surface of the shell of the heat exchanger and the outer flat surfaces of both flat tubes positioned on the outermost layer of the tube assembly In between, a metal elongated coil formed into a coarse coil spring shape is interposed as a tube support member, and the longitudinal direction of this tube support member is provided in a direction crossing the flow of cooling water, A tube support structure for a heat exchanger for an EGR cooler, characterized in that the coolant in the heat exchanger passes between the roughly wound wires of the tube support member to prevent the coolant from staying.   In a heat exchanger for an EGR cooler in which a tube assembly in which a plurality of flat tubes are stacked is incorporated in a shell, the inner wall surface of the shell of the heat exchanger and the outer flat surfaces of both flat tubes positioned on the outermost layer of the tube assembly In the meantime, a corrugated sheet formed by bending an elongated thin sheet material into a corrugated shape is interposed as a tube support member, and the longitudinal direction of the tube support member and its corrugated side face both in the direction intersecting the coolant flow. A tube support structure for a heat exchanger for an EGR cooler, wherein the cooling water in the heat exchanger passes through the waved side surface of the tube support member to prevent the cooling water from staying.   The heat exchanger for an EGR cooler according to claim 1 or 2, wherein at least one of the tube support members is disposed between at least one of the shell of the heat exchanger and the flat tubes. Tube support structure.   The tube support structure for a heat exchanger for an EGR cooler according to claim 1 or 2, wherein one or more of the tube support members are disposed between the laminated flat tubes.   5. The tube support structure for a heat exchanger for an EGR cooler according to claim 1, wherein a plurality of tube support members having a length shorter than a flat width of the flat tube are provided as the tube support member. .

Images