Information
-
Patent Grant
-
6283200
-
Patent Number
6,283,200
-
Date Filed
Thursday, December 2, 199924 years ago
-
Date Issued
Tuesday, September 4, 200123 years ago
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Inventors
-
Original Assignees
-
Examiners
- Lazarus; Ira S.
- McKinnon; Terrell
Agents
- Harness, Dickey & Pierce, PLC
-
CPC
-
US Classifications
Field of Search
US
- 165 173
- 165 151
- 165 153
- 165 148
- 165 176
- 165 175
-
International Classifications
-
Abstract
A heat exchanger has plural tubes and a header tank communicating with each tube. The tank has an opening through which coolant is introduced, and an elevated portion formed in the vicinity of the opening by elevating a wall of the tank outwardly, so that a dimension of the tank including the elevated portion becomes larger than a dimension of the tank excluding the elevated portion in a direction perpendicular to a longitudinal direction of the tank. As a result, a volume and a sectional area of the tank in the vicinity of the opening are increased, thereby decreasing pressure loss of coolant flowing into the tank. Therefore, even when a size of the tank is reduced to reduce a size of the heat exchanger, pressure loss of coolant flowing into the tank is restricted from increasing.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
This application relates to and claims priority from Japanese Patent Application Nos. 10-344472 filed on Dec. 3, 1998 and 11-287207 filed on Oct. 7, 1999, the contents of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a heat exchanger, and is suitably applied to a radiator which cools engine coolant of a vehicle engine.
2. Related Art
Conventionally, a radiator has plural tubes, a first header tank connected to one flow-path end of each tube and a second header tank connected to the other flow-path end of each tube. Coolant introduced into the first header tank is distributed into each tube and is heat-exchanged with air while flowing through each tube. After heat exchange, coolant is discharged from each tube and is collected into the second header tank.
Recently, while the number of devices disposed in an engine compartment of a vehicle has been increased, size reduction of each device such as a radiator has been demanded to enlarge a passenger compartment of the vehicle without increasing a vehicle body size. It is proposed to reduce a volume of the header tank to reduce a size of the radiator.
However, the header tank has an opening through which coolant flows into the header tank, and the opening is open in a direction perpendicular to a longitudinal direction of the header tank, for example. Therefore, when coolant flows into the header tank, coolant changes a flow direction by approximately 90 degrees at the opening. Further, a sectional area of the header tank is relatively small due to volume reduction of the header tank in comparison with an area of the opening, a sectional area of a coolant flow passage of the radiator is largely decreased in the header tank. As a result, coolant may largely lose pressure thereof in the header tank, and flow resistance of coolant in the header tank may be increased.
SUMMARY OF THE INVENTION
In view of the foregoing problems, it is an object of the present invention to provide a heat exchanger having a header tank reduced in size and decreasing pressure loss of fluid in the header tank.
According to the present invention, a heat exchanger has plural tubes through which fluid flows and a tank communicating with each tube. The tank has an opening open in a direction at a preset angle to a longitudinal direction of the tank, and an elevated portion elevated outwardly in the vicinity of the opening. A dimension of the tank including the elevated portion in a direction perpendicular to the longitudinal direction of the tank is larger than a dimension of the tank excluding the elevated portion in the direction perpendicular to the longitudinal direction of the tank.
As a result, a volume of the tank and a sectional area of the tank in the vicinity of the opening are increased. Therefore, when fluid enters the tank while changing a flow direction through the opening, pressure loss of fluid is decreased. Further, since the sectional area of the tank in the vicinity of the opening is increased, a sectional area of a fluid flow passage of the heat exchanger is restricted from being largely decreased in the tank. As a result, pressure loss of fluid in the tank is further decreased. Thus, a size of the tank is reduced while pressure loss of fluid in the tank is decreased.
Preferably, an inner diameter of an inserted portion of a pipe inserted into the opening is increased toward an inside of the tank. As a result, fluid flows smoothly at a connection portion between the pipe and the tank, and pressure loss of fluid in the tank is further decreased.
More preferably, the opening is formed in the elevated portion. As a result, a width of the heat exchanger including the pipe in an air flow direction is maintained even when a width of the tank in the air flow direction is increased by the elevated portion.
BRIEF DESCRIPTION OF THE DRAWINGS
This and other objects and features of the present invention will become more readily apparent from a better understanding of the preferred embodiments described below with reference to the accompanying drawings, in which:
FIG. 1
is a front view showing a radiator according to a first preferred embodiment of the present invention;
FIG. 2
is an enlarged view showing a portion indicated by arrow II in
FIG. 1
;
FIG. 3
is a sectional view taken along line III—III in
FIG. 2
;
FIG. 4
is a sectional view taken along line IV—IV in
FIG. 2
;
FIG. 5
is a sectional view showing a header tank and a pipe of a radiator according to a modification of the first embodiment;
FIGS. 6A and 6B
are sectional views each showing a header tank in which an oil cooler is disposed and a pipe of a radiator according to another modification of the first embodiment;
FIG. 7
is a partial front view showing a radiator according to a second preferred embodiment of the present invention; and
FIG. 8
is a sectional view taken along line VIII—VIII in FIG.
7
.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferred embodiments of the present invention are described hereinafter with reference to the accompanying drawings.
(First Embodiment)
A first preferred embodiment of the present invention will be described with reference to
FIGS. 1-6B
. In the first embodiment, the present invention is applied to a radiator for cooling engine coolant of a vehicle engine. In
FIG. 1
, a radiator
100
is viewed from a downstream air side with respect to air passing through the radiator
100
, that is, from a rear side of the same.
As shown in
FIG. 1
, the radiator
100
has plural aluminum tubes
111
through which engine coolant flows, and plural aluminum corrugated fins
112
disposed between adjacent tubes
111
to facilitate heat exchange between air and engine coolant. The tubes
111
and the fins
112
form a heat exchange core portion
110
which cools engine coolant through heat exchange between engine coolant and air. Each fin
112
is clad with brazing material on both side surfaces thereof, and is brazed to the tubes
111
using the brazing material. Plates
113
are attached to the core portion
110
to reinforce strength of the core portion
110
.
A first header tank
121
is disposed at one flow-path end of each tube
111
, that is, a right end of each tube
111
in FIG.
1
. The first header tank
121
extends in a direction perpendicular to a longitudinal direction of each tube
111
, and communicates with each tube
111
. Engine coolant from the engine flows into the first header tank
121
and is distributed to each tube
111
. A second header tank
122
is disposed at the other flow-path end of each tube
111
. The second header tank
122
also extends in the direction perpendicular to the longitudinal direction of each tube
111
, and communicates with each tube
111
. After engine coolant is heat-exchanged with air, engine coolant is discharged from each tube
111
, and is collected into the second header tank
122
. Hereinafter, the first and second header tanks
121
,
122
are collectively referred to as a tank
120
.
As shown in
FIG. 1
, the tank
120
has an opening
123
at a lower end of the tank
120
in a longitudinal direction thereof. As shown in
FIG. 3
, the opening
123
is open in a direction perpendicular to the longitudinal direction of the tank
120
. A cylindrical connection pipe
130
is inserted into the opening
123
and is connected to the tank
120
. The pipe
130
is also connected to an external pipe (not shown) which is connected to the engine. Further, as shown in
FIGS. 3 and 4
, an inner diameter of an inserted portion of the pipe
130
is increased toward an inside of the tank
120
. The tank
120
and the pipe
130
are made of aluminum, and are integrally brazed to each other by brazing.
Further, as shown in
FIGS. 2-4
, the tank
120
has an elevated portion
124
formed by elevating a wall of the tank
120
outwardly in the vicinity of the opening
123
. As shown in
FIG. 3
, the tank
120
has a dimension Li in a direction perpendicular to the longitudinal direction of the tank
120
(i.e., in an air flow direction) where the elevated portion
124
is formed. On the other hand, the tank
120
has a dimension L in the direction perpendicular to the longitudinal direction of the tank
120
where the elevated portion
124
is not formed. The dimension Li is larger than the dimension L. Further, as shown in
FIG. 2
, the opening
123
is disposed in a lower portion of the elevated portion
124
to be adjacent to the lower end of the tank
120
. Referring back to
FIG. 1
, the tank
120
also has an elevated portion in the vicinity of an opening through which coolant is discharged. The opening is disposed at an upper end of the tank
120
in the longitudinal direction thereof in FIG.
1
.
Referring to
FIG. 3
, the number of the tubes
111
connected to a portion of the tank
120
between a center of the elevated portion
124
in the longitudinal direction of the tank
120
and the lower end of the tank
120
(hereinafter referred to as the lower tank portion) is smaller than the number of the tubes
111
connected to a portion of the tank
120
between the center of the elevated portion
124
and an upper end of the tank
120
in the longitudinal direction of the tank
120
(hereinafter referred to as the upper tank portion). As a result, when coolant flows into the tank
120
, coolant mostly flows into the upper tank portion and less flows into the lower tank portion. The opening
123
is disposed in the elevated portion
124
to be shifted toward the lower tank portion.
According to the first embodiment, the tank
120
has the opening
123
and the elevated portion
124
formed in the vicinity of the opening
123
. The dimension Li of the tank
120
including the elevated portion
124
is larger than the dimension L of the tank
120
excluding the elevated portion
124
. Therefore, a volume of the tank
120
and a sectional area of the tank
120
in the vicinity of the opening
123
are increased. As a result, when coolant enters the tank
120
through the opening
123
and changes a flow direction at the opening
123
, pressure loss of coolant is decreased. Also, since the sectional area of the tank
120
in the vicinity of the opening
123
is increased, a sectional area of a coolant flow passage of the radiator
100
is restricted from largely decreasing in the tank
120
. Therefore, pressure loss of coolant in the tank
120
is decreased. Thus, even if a size of the tank
120
is decreased to reduce a size of the radiator
100
, pressure loss of coolant in the tank
120
is restricted from increasing.
The elevated portion
124
may be formed opposite to the opening
123
, that is, at the right side in FIG.
3
. Also in this case, the volume of the tank
120
and the sectional area of the tank
120
in the vicinity of the opening
123
are increased. However, as shown in
FIG. 3
, a width Lo of the radiator
100
including the pipe
130
in the air flow direction is the sum of the dimension L and a dimension of the pipe
130
in an axial direction thereof. Therefore, if the elevated portion
124
is formed opposite to the opening
123
, the width Lo is increased by a difference between the dimension L and the dimension Li.
According to the first embodiment, the elevated portion
124
is formed on the same side of the tank
120
as the opening
123
, that is, the opening
123
is formed in the elevated portion
124
. Therefore, the width Lo is not increased by the elevated portion
124
, while pressure loss of coolant in the tank
120
is decreased. When the dimension L is smaller than a diameter D of the opening
123
(i.e., an inner diameter of the pipe
130
), pressure loss of coolant in the tank
120
is effectively decreased. In the present embodiment, the diameter D is approximately twice as large as the dimension L.
Further, in the first embodiment, as shown in
FIG. 3
, the opening
123
is positioned in the lower portion of the elevated portion
124
to be shifted toward the lower tank portion into which less coolant flows. As a result, the upper tank portion into which coolant mostly flows is enlarged by the elevated portion
124
. Therefore, when coolant enters the tank
120
and changes the flow direction, pressure loss of coolant is effectively decreased.
Further, in the first embodiment, the inner diameter of the inserted portion of the pipe
130
inserted into the opening
123
is increased toward the inside of the tank
120
. Therefore, coolant flows more smoothly at a connection portion between the pipe
130
and the tank
120
, and pressure loss of coolant in the tank
120
is further decreased. Furthermore, in the first embodiment, the tank
120
also has the elevated portion in the vicinity of the opening through which coolant is discharged. As a result, a flow resistance of coolant in the radiator
100
is further reduced. Further, the first and second header tanks
121
,
122
are formed using common parts, thereby reducing manufacturing cost.
As shown in
FIG. 5
, the opening
123
may be opened in a direction at 45 degrees or the like to the longitudinal direction of the tank
120
. Further, as shown in
FIGS. 6A and 6B
, an oil cooler
200
may be disposed in the tank
120
. Hydraulic oil such as engine lubricant oil or automatic transmission fluid flowing in the oil cooler
200
exchanges heat with engine coolant flowing in the tank
120
so that hydraulic oil is cooled.
(Second Embodiment)
A second preferred embodiment of the present invention will be described with reference to
FIGS. 7 and 8
. In this embodiment, components which are substantially the same as those in the previous embodiment are assigned the same reference numerals, and the explanation thereof is omitted.
In the second embodiment, as shown in
FIGS. 7 and 8
, the opening
123
is disposed at an upper longitudinal end of the tank
120
in a longitudinal direction thereof. Also in this case, the similar effect as with the first embodiment is obtained.
The present invention may be applied to other heat exchangers such as a condenser.
Although the present invention has been fully described in connection with preferred embodiments thereof with reference to the accompanying drawings, it is to be noted that various changes and modifications will become apparent to those skilled in the art. Such changes and modifications are to be understood as being within the scope of the present invention as defined by the appended claims.
Claims
- 1. A heat exchanger comprising:a plurality of tubes through which fluid flows; a tank disposed at a flow-path end of each tube to extend in a direction perpendicular to a longitudinal direction of each tube and communicating with each tube, the tank including an opening open in a direction at a preset angle to a longitudinal direction of the tank and connectable to an external pipe, and an elevated portion elevated outwardly in the vicinity of the opening, wherein a dimension of the tank including the elevated portion in a direction perpendicular to the longitudinal direction of the tank is larger than a dimension of the tank excluding the elevated portion in the direction perpendicular to the longitudinal direction of the tank; and wherein the elevated portion is provided on the same surface of the tank as the opening portion.
- 2. The heat exchanger according to claim 1, wherein the opening is disposed in the elevated portion.
- 3. The heat exchanger according to claim 1, further comprising a pipe inserted into the opening and connected to the tank, wherein an inner diameter of an inserted portion of the pipe inserted into the opening is increased toward an inside of the tank.
- 4. The heat exchanger according to claim 3, wherein the pipe is formed into a cylindrical shape.
- 5. The heat exchanger according to claim 1, wherein:the number of the tubes connected between the opening and a first end of the tank in the longitudinal direction of the tank is less than the number of the tubes connected between the opening and a second end of the tank in the longitudinal direction of the tank; and the opening is disposed in the elevated portion to be shifted from a center of the elevated portion in the longitudinal direction of the tank toward the first end of the tank.
- 6. The heat exchanger according to claim 1, wherein the tank is made of metal.
- 7. The heat exchanger according to claim 1, wherein the opening is open in a direction substantially perpendicular to the longitudinal direction of the tank.
- 8. The heat exchanger according to claim 1, wherein the opening is open in a direction at approximately 45 degrees to the longitudinal direction of the tank.
- 9. The heat exchanger according to claim 1, further comprising an oil cooler disposed in the tank, wherein an oil flowing in the oil cooler exchanges heat with the fluid flowing in the tank to be cooled.
- 10. The heat exchanger according to claim 1, wherein the fluid flows into the tank through the opening.
- 11. The heat exchanger according to claim 10, wherein the opening is disposed at a lower end portion of the tank in the longitudinal direction of the tank.
- 12. The heat exchanger according to claim 10, wherein the opening is disposed at an upper end portion of the tank in the longitudinal direction of the tank.
- 13. The heat exchanger according to claim 1, wherein the tank has a pipe protruding from the elevated portion and having the opening at a front end thereof, the opening being open in the direction that is non-perpendicular to the longitudinal direction of the tank so that the fluid introduced from the external pipe through the opening is turned at an outside angle to enter the tube when the external pipe is connected to the opening.
- 14. The heat exchanger according to claim 1, wherein the elevated portion has the opening at a front end thereof.
- 15. The heat exchanger according to claim 1, wherein a direction in which the elevated portion is elevated is approximately parallel to the direction in which the opening is open.
- 16. The heat exchanger according to claim 1, wherein the elevated portion is elevated in a direction that is approximately perpendicular to the longitudinal direction of each tube.
- 17. A heat exchanger comprising:a plurality of tubes through which fluid flows; a tank disposed at a flow-path end of each tube to extend in a direction perpendicular to a longitudinal direction of each tube and communicating with each tube, the tank including an opening open in a direction at a preset angle to a longitudinal direction of the tank and connectable to an external pipe, and an elevated portion elevated outwardly in the vicinity of the opening, wherein a dimension of the tank including the elevated portion in a direction perpendicular to the longitudinal direction of the tank is larger than a dimension of the tank excluding the elevated portion in the direction perpendicular to the longitudinal direction of the tank; the opening is formed into a substantially circular shape; and the dimension of the tank excluding the elevated portion is smaller than a diameter of the opening.
- 18. The heat exchanger according to claim 17, wherein the diameter of the opening is approximately twice as large as the dimension of the tank excluding the elevated portion.
- 19. A heat exchanger comprising:a plurality of tubes through which fluid flows; a first tank disposed at a first flow-path end of each tube to extend in a direction perpendicular to a longitudinal direction of each tube and communicating with each tube, the first tank including a first opening disposed at an end of the first tank in a longitudinal direction thereof, and a first elevated portion elevated outwardly in the vicinity of the first opening, the first elevated portion being provided on the same surface of the first tank as the first opening; a second tank disposed at a second flow-path end of each tube to extend in the direction perpendicular to the longitudinal direction of each tube and communicating with each tube, the second tank including a second opening disposed at an end of the second tank in a longitudinal direction thereof, and a second elevated portion elevated outwardly in the vicinity of the second opening, the second elevated portion being provided on the same surface of the second tank as the second opening, wherein: the fluid flows into the first opening and is discharged from the second opening; the first opening and the second opening are disposed diagonally; a dimension of the first tank including the first elevated portion in a direction perpendicular to the longitudinal direction of the first tank is larger than a dimension of the first tank excluding the first elevated portion in the direction perpendicular to the longitudinal direction of the first tank; and a dimension of the second tank including the second elevated portion in a direction perpendicular to the longitudinal direction of the second tank is larger than a dimension of the second tank excluding the second elevated portion in the direction perpendicular to the longitudinal direction of the second tank.
Priority Claims (2)
Number |
Date |
Country |
Kind |
10-344472 |
Dec 1998 |
JP |
|
11-287207 |
Oct 1999 |
JP |
|
US Referenced Citations (10)