U.S. patent application number 11/574822 was filed with the patent office on 2007-11-08 for header tank for heat exchanger.
This patent application is currently assigned to CALSONIC KANSEI CORPORATION. Invention is credited to Shiro Ikuia, Seiji Mashiko, Kazutaka Uebayashi.
Application Number | 20070256821 11/574822 |
Document ID | / |
Family ID | 36036430 |
Filed Date | 2007-11-08 |
United States Patent
Application |
20070256821 |
Kind Code |
A1 |
Mashiko; Seiji ; et
al. |
November 8, 2007 |
Header Tank for Heat Exchanger
Abstract
A header tank for a heat exchanger includes tank forming
sections that are joined into a tubular shape with a substantially
square cross-section. The header tank has a refrigerant low path
formed inside the tank forming sections include a tank upper
section (31) in which tube insertion holes (31a) for connecting
tubes of a heat exchanger core are formed. The tank lower section
(33) having a substantially U-shaped refrigerant split-flow groove
(33A) that has, in its longitudinal direction, communication holes
(33a, 33b) for the refrigerant. The tank forming sections include a
plate section (35) for closing an opening of the refrigerant
split-flow groove (33A) to form a refrigerant split-flow path (37)
inside the tank lower section.
Inventors: |
Mashiko; Seiji; (Kanagawa,
JP) ; Uebayashi; Kazutaka; (Gunma, JP) ;
Ikuia; Shiro; (Tochigi, JP) |
Correspondence
Address: |
FOLEY AND LARDNER LLP;SUITE 500
3000 K STREET NW
WASHINGTON
DC
20007
US
|
Assignee: |
CALSONIC KANSEI CORPORATION
5-24-15, Minamidai, Nakano-ku,
Tokyo
JP
164-8602
|
Family ID: |
36036430 |
Appl. No.: |
11/574822 |
Filed: |
September 7, 2005 |
PCT Filed: |
September 7, 2005 |
PCT NO: |
PCT/JP05/16442 |
371 Date: |
May 11, 2007 |
Current U.S.
Class: |
165/160 ;
29/890.052 |
Current CPC
Class: |
F25B 39/04 20130101;
F28F 9/0273 20130101; Y10T 29/49389 20150115; F28F 9/02 20130101;
F28F 9/0214 20130101 |
Class at
Publication: |
165/160 ;
029/890.052 |
International
Class: |
F28F 9/02 20060101
F28F009/02 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 8, 2004 |
JP |
2004-260961 |
Claims
1. A header tank for a heat exchanger, comprising: a plurality of
tank constituent portions joined into a cylindrical shape with a
substantially square cross-section; and a refrigerant passage
formed within the plurality of tank constituent portions; wherein
the plurality of tank constituent portions include: a tank upper
portion with a plurality of tube insertion holes for connection of
tubes of the heat exchanger core formed; a tank lower portion
including a refrigerant distribution groove with a substantially
U-shaped section which has a plurality of refrigerant communication
holes in a longitudinal direction; a plate portion closing an
opening of the refrigerant distribution groove to form a
refrigerant distribution passage within the tank lower portion.
2. A header tank for a heat exchanger, comprising: a plurality of
tank constituent portions joined into a cylindrical shape with a
substantially square section; wherein the plurality of tank
constituent portions include: a tank upper portion with a plurality
of tube insertion holes for connection of tubes of the heat
exchanger core formed; a tank lower portion including a refrigerant
distribution portion with a substantially circular section
integrally formed with a body of the lower portion, the refrigerant
distribution portion having a plurality of refrigerant
communication holes in a longitudinal direction.
3. A header tank of a heat exchanger, comprising: a header tank
formed of a single constituent material into a tubular shape with a
substantially square section, wherein an upper face of the header
tank includes a plurality of tube insertion holes for connection of
tubes of the heat exchanger core; and a lower face of the header
tank integrally includes a refrigerant distribution portion with a
substantially circular section with a tank body, the refrigerant
distribution portion includes a plurality of refrigerant
communication holes along a longitudinal direction.
4. The header tank according to claim 2, wherein the refrigerant
distribution portion includes a part of a plate material as a tank
constituent member which is shaped to have a substantially
.OMEGA.-shaped section; and the tank includes a plurality of joints
in a portion where portions of the plate material are laid on each
other in the substantially .OMEGA.-shaped section.
5. The header tank for a heat exchanger according to claim 1,
wherein the refrigerant communication holes include: first
communication holes through which refrigerant in gas phase passes;
and second communication holes through which refrigerant in liquid
phase passes, and the refrigerant distribution groove includes: the
first communication holes in upper part in a direction of gravity
when the refrigerant flows within the header tank; and the second
communication holes in lower part in the direction of gravity.
6. The header tank for a heat exchanger according to claim 1,
wherein each of the refrigerant communication holes is positioned
to have half or more of a sectional area overlapped on a range of
thickness of the tubes.
7. The header tank for a heat exchanger according to claim 1,
wherein the communication holes and the tubes match each other in
terms of longitudinal positions in the header tank.
8. The header tank for a heat exchanger according to claim 4,
wherein the joint portions are caulked.
9. The header tank for a heat exchanger according to claim 4,
wherein each of the joint portions includes a hole; and a
protrusion fit in the hole.
10. The header tank for a heat exchanger according to claim 4,
wherein each of the joint portions includes a hole; and a
protrusion which pierces the hole and has a crushed tip.
11. The header tank for a heat exchanger according to claim 2,
wherein the refrigerant distribution portion includes: a
refrigerant distribution pipe; a support portion supporting the
refrigerant distribution pipe; and communication holes which
communicates with refrigerant passages on both sides of the support
portion.
12. The header tank for a heat exchanger according to claim 9,
wherein the communication holes have an equivalent diameter of 1.0
mm or more.
13. The header tank for a heat exchanger according to claim 2,
wherein the refrigerant distribution portion includes: a
refrigerant distribution pipe including a refrigerant distribution
passage defined inside; a support portion supporting the
refrigerant distribution pipe; and a communication holes allowing
refrigerant passages on both sides of the support portion and the
refrigerant distribution passage to communicate with each
other.
14. A method of manufacturing a header tank for a heat exchanger,
comprising the steps of: opening a hole in a first portion of a
sheet; forming a protrusion in a second portion of the sheet;
winding a third portion between the first and second portions of
the sheet to bring the first and second portions close to each
other to form a refrigerant distribution passage; piercing the hole
with the protrusion; crushing a tip of the protrusion piercing the
hole; and bending fourth and fifth portions outside of the first
and second portions in the sheet toward the wound third portion to
form a refrigerant passage.
15. The method of manufacturing a header tank for a heat exchanger
according to claim 14, wherein communication holes are opened in
the third portion of the sheet.
Description
TECHNICAL FIELD
[0001] The present invention relates to a header tank for a heat
exchanger used in vehicles and the like and specifically relates to
a structure of a header tank having a function to equally
distribute refrigerant to each tube.
BACKGROUND ART
[0002] A general heat exchanger used in vehicles and the like
includes a heat exchanger core having flat tubes and fins
alternately arranged and header tanks causing refrigerant to flow
into the heat exchanger core. The header tanks among these are
separated into an inlet header tank and an outlet header tank. The
inlet header tank causes externally supplied refrigerant to flow
into each tube of the heat exchanger core. The outlet header tank
joins together flows of refrigerant which has exchanged heat with
cooling air while passing through the tubes of the heat exchanger
core and discharges the same to the outside. The arrangement of the
header tanks includes various types depending on path of
refrigerant, and a general structure is described herein.
[0003] The inlet header tank supplies the refrigerant from one end
thereof. In the inlet header tank, more refrigerant is flown into
tubes located further back in a supply direction of the
refrigerant. The amount of refrigerant flowing into tubes located
in the front side is less than that of the tubes located in the
back side. Accordingly, the following header tank is proposed.
Specifically, a refrigerant distribution pipe provided with a
plurality of refrigerant passage holes is inserted in the header
tank, and refrigerant is equally distributed from the refrigerant
passage holes to the individual tubes (for example, see the
Japanese Patent Laid-open Publications No. 8-86591 and No.
9-166368).
DISCLOSURE OF THE INVENTION
[0004] However, the header tank including the refrigerant
distribution pipe inside requires the refrigerant distribution pipe
and a holding plate holding the same, increasing component cost.
Moreover, the header tank requires a process to attach these
components to the inside of the header tank, increasing assembly
cost. Accordingly, the aforementioned related example cannot avoid
an increase in cost.
[0005] When the header tank with the refrigerant distribution pipe
assembled thereto is brazed in a furnace, there is a temperature
difference caused between the header tank and the refrigerant
distribution pipe during heating or cooling. Differences in
expansion and shrinkage due to the temperature difference distort
the refrigerant distribution pipe inside the tank, thus reducing
the distribution efficiency.
[0006] An object of the present invention is to reduce the
manufacturing cost and improve the distribution efficiency in a
header tank including a function inside to distribute
refrigerant.
[0007] A first aspect of the present invention provides a header
tank for a heat exchanger. The header tank includes a plurality of
tank constituent portions joined into a cylindrical shape with a
substantially square cross-section. The header tank includes a
refrigerant passage formed within the plurality of tank constituent
portions. The plurality of tank constituent portions include a tank
upper portion (31) with a plurality of tube insertion holes (31a)
for connection of tubes (21) of a heat exchanger core formed. The
plurality of tank constituent portions include a tank lower portion
(33) including a refrigerant distribution groove (33A) with a
substantially U-shaped section which has a plurality of refrigerant
communication holes (33a, 33b) in a longitudinal direction. The
plurality of tank constituent portions include a plate portion (35)
which closes an opening of the refrigerant distribution groove
(33A) to form a refrigerant distribution passage (37) within the
tank lower portion.
[0008] A second aspect of the present invention provides a header
tank for a heat exchanger. The header tank includes a plurality of
tank constituent portions joined into a cylindrical shape with a
substantially square section. The plurality of tank constituent
portions include a tank upper portion (51) with a plurality of tube
insertion holes (51a) for connection of tubes (21) of a heat
exchanger core formed. The plurality of tank constituent portions
include a tank lower portion (53) including a refrigerant
distribution portion (53A) with a substantially circular section
integrally formed with a body of the lower portion, the refrigerant
distribution portion having a plurality of refrigerant
communication holes (53a, 53b) in a longitudinal direction.
[0009] A third aspect of the present invention provides a header
tank (83) of a heat exchanger. The header tank (83) includes the
header tank (83) formed of a single constituent material into a
tubular shape with a substantially square section. An upper face of
the header tank includes a plurality of tube insertion holes (61a)
for connection of tubes (21) of a heat exchanger core. A lower face
of the header tank integrally includes a refrigerant distribution
portion (63A) with a substantially circular section with a tank
body, the refrigerant distribution portion (63A) including a
plurality of refrigerant communication holes (63a, 63b) in a
longitudinal direction.
[0010] The refrigerant distribution portion (53A) includes a part
of a plate material as a tank constituent member which is shaped
into a substantially Q-shaped section. The tank may include a
plurality of joints (55A) in a portion where portions of the plate
material are laid on each other in the substantially Q-shaped
section.
[0011] The refrigerant communication holes (33a, 33b) include:
first communication holes (33a) through which refrigerant in gas
phase passes. The communication holes include second communication
holes (33b) through which refrigerant in liquid phase passes. The
refrigerant distribution groove (33A) includes the first
communication holes (33a) in upper part in a direction of gravity
when the refrigerant flows within the header tank. The refrigerant
distribution groove (33A) includes the second communication holes
(33b) in lower part in the direction of gravity.
[0012] Each of the refrigerant communication holes (33a, 33b) may
be positioned to have half or more of a sectional area overlapping
a range of thickness (t) of the tubes (21).
[0013] The communication holes (33a, 33b) and the tubes (21) may
match each other in terms of longitudinal positions in the header
tank.
[0014] The joint portion (55A) may be caulked.
[0015] Each of the joint portions (55A) may include a hole and a
protrusion fit in the hole.
[0016] Each of the joint portions (55C) may include a hole (55a)
and a protrusion (55b) which pierces the hole (55a) and has a
crushed tip.
[0017] The refrigerant distribution portion (53B) includes a
refrigerant distribution pipe (37). The refrigerant distribution
portion (53B) includes a support portion (55) supporting the
refrigerant distribution pipe (37). The refrigerant distribution
portion (53B) may include communication holes (53p) communicating
with refrigerant passages on both sides of the support portion
(55).
[0018] The communication holes (53p) may have an equivalent
diameter of 1.0 mm or more.
[0019] The refrigerant distribution portion (53F) includes a
refrigerant distribution pipe (57) having a refrigerant
distribution passage defined inside. The refrigerant distribution
portion (53F) includes a support portion (55) supporting the
refrigerant distribution pipe (57). The refrigerant distribution
portion (53F) may include communication holes (53q) allowing
refrigerant passages on both sides of the support portion 55 and
the refrigerant distribution passage to communicate with each
other.
[0020] A fourth aspect of the present invention provides a method
of manufacturing a header tank for a heat exchanger including the
following steps. In a first step, a hole (55a) is opened in a first
portion (101d) of a sheet (101). In a second step, a protrusion
(55b) is formed in a second portion (101e) of the sheet (101). In a
third step, a third portion (101a) between the first and second
portions (55a, 55b) of the sheet (101) is wound to bring the first
and second portions (101d, 101e) close to each other to form a
refrigerant distribution passage. In a fourth step, the hole (55a)
is pierced with the protrusion (55b). In a fifth step, a tip of the
protrusion (55b) piercing the hole (55a) is crushed. In a sixth
step, fourth and fifth portions (101b, 101c) outside of the first
and second portions (101d, 101e) in the sheet (101) are bent toward
the wound third portion (101a) to form a refrigerant passage. In a
seventh step, a communication hole (53f) may be opened in the third
portion (101a) of the sheet (101).
[0021] According to the first aspect of the present invention, the
refrigerant distribution groove is formed in the tank lower
portion, and the refrigerant communication holes are provided for
the refrigerant distribution groove. Moreover, the opening is
closed by the plate portion to form the refrigerant distribution
passage. Such a structure eliminates the need to manufacture a
refrigerant distribution pipe, a holding plate, and the like as
separate components, thus reducing component cost. Such a structure
eliminates the need for a process to attach the refrigerant
distribution pipe, holding plate, and the like to the inside of the
tank, thus reducing assembly cost. Accordingly, the lower header
tank 13 has the same function as a header tank including the
refrigerant distribution pipe inside while further reducing
manufacturing cost. The integration of the refrigerant distribution
portion and the tank lower portion prevents occurrence of
distortion in the refrigerant distribution groove due to the
temperature difference during brazing and prevents reduction of the
distribution efficiency due to the distortion within the tank as is
observed in the refrigerant distribution pipe.
[0022] According to the second aspect of the present invention, the
lower tank lower and the refrigerant distribution portion with a
substantially circular section are integrally formed, and the
refrigerant communication holes are formed in the refrigerant
distribution portion. Such a structure eliminates the need to
manufacture the refrigerant distribution pipe, holding plate, and
plate as separate components, thus reducing component cost. Such a
structure eliminates the need for a process to attach the
refrigerant distribution pipe, holding plate, and the like to the
inside of the tank, thus reducing assembly cost. Accordingly, this
structure has the same function as that of the header tank
including the refrigerant distribution pipe inside while further
reducing the manufacturing cost. Integration of the tank lower
portion and refrigerant distribution portion prevents occurrence of
distortion in the refrigerant distribution portion due to the
temperature difference during brazing and prevents reduction of the
distribution efficiency due to the distortion within the tank as is
observed in the refrigerant distribution pipe.
[0023] According to the third aspect of the present invention, the
tank upper portion and tank lower portion are integrally formed,
and the body of the header tank and the refrigerant distribution
portion with a substantially circular section are integrally
formed. Furthermore, the refrigerant communication holes are formed
in this refrigerant distribution portion. Such a structure
eliminates the need to manufacture not only the refrigerant
distribution pipe, holding plate, and plate but also the tank upper
portion and tank lower portion as separate components, thus
reducing the number of components. The component cost can be
therefore reduced. Such a structure eliminates the need for a
process to attach the refrigerant distribution pipe, holding plate,
and the like to the inside of the tank, thus reducing assembly
cost. Accordingly, this structure has the same function as that of
the header tank including the refrigerant distribution pipe inside
while further reducing the manufacturing cost. Integration of the
body of the header tank and refrigerant distribution portion
prevents occurrence of distortion in the refrigerant distribution
groove due to the temperature difference during brazing and
prevents reduction of the distribution efficiency due to the
distortion within the tank as is observed in the refrigerant
distribution pipe.
[0024] The joint portions prevent separation of portions of the
plate materials laid on each other to improve the brazing
properties.
[0025] The individual communication holes allow gas and liquid of
the refrigerant to be efficiently discharged therethrough.
[0026] The positioning of the communication holes and tubes allows
refrigerant having passed through the communication hole to
efficiently flow into the tubes.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 is an external perspective view showing an entire
structure of a heat exchanger according to a first embodiment.
[0028] FIG. 2 is a cross sectional view of a lower header tank
taken along a line II-II of FIG. 1.
[0029] FIG. 3 is a longitudinal sectional view taken along a line
III-III of FIG. 2.
[0030] FIG. 4 is a cross sectional view of an upper header tank
taken along a line IV-IV of FIG. 1
[0031] FIG. 5 is a cross sectional view of a lower header tank for
a heat exchanger according to a second embodiment.
[0032] FIG. 6 is a cross sectional view of a join portion of the
lower header tank of the heat exchanger according to the second
embodiment.
[0033] FIG. 7 is a cross sectional view of a lower header tank
according to a third embodiment.
[0034] FIG. 8 is a perspective view of a header tank according to a
fourth embodiment.
[0035] FIG. 9 is a transverse cross-sectional view of a
distribution pipe having a joint portion of another aspect in the
header tank of FIG. 8.
[0036] FIG. 10 is a longitudinal cross-sectional view of the header
tank of FIG. 8.
[0037] FIG. 11 is a cross sectional view of a distribution pipe of
a header tank according to a fifth embodiment.
[0038] FIG. 12 is a cross sectional view of the distribution pipe
of FIG. 11 with a protrusion and a caulking hole being not attached
thereto.
[0039] FIG. 13 is a side view of a metal sheet as a raw
material.
[0040] FIG. 14A is a schematic view showing a first step of a
method of manufacturing a header tank.
[0041] FIG. 14B is a schematic view showing a second step of the
method of manufacturing a header tank.
[0042] FIG. 14C is a schematic view showing a third step of the
method of manufacturing a header tank.
[0043] FIG. 14D is a schematic view showing a fourth step of the
method of manufacturing a header tank.
[0044] FIG. 14E is a schematic view showing a fifth step of the
method of manufacturing a header tank.
[0045] FIG. 14F is a schematic view showing a sixth step of the
method of manufacturing a header tank.
[0046] FIG. 15 is a perspective view of a header tank according to
a sixth embodiment.
[0047] FIG. 16 is a cross sectional view of the header tank of FIG.
15.
[0048] FIG. 17 is a perspective view showing a header tank of a
different aspect from the header tank of FIG. 15.
[0049] FIG. 18 is a cross sectional view of the header tank of FIG.
17.
BEST MODE FOR CARRYING OUT THE INVENTION
[0050] Hereinafter, a description is given of embodiments showing
best modes for carrying out a header tank for a heat exchanger
according to the present invention.
First Embodiment
[0051] FIG. 1 is an external perspective view showing an entire
structure of a heat exchanger according to an embodiment. A heat
exchanger 11 roughly includes a lower header tank 13, an upper
header tank 15, and a heat exchanger core 17. The heat exchanger
core 17 includes a plurality of tubes 21, through which refrigerant
19 flows, and cooling fins 23. The tubes 21 and cooing fins 23 are
alternately arranged. The lower end of the heat exchanger core 17
is connected to the lower header tank 13 and communicates with an
end of each tube 21. The upper end of the heat exchanger core 17 is
connected to the upper header tank 15 and communicates with the
other end of each tube 21.
[0052] Both ends of the lower header tank 13 are closed by end
plates 25. One of the both ends is connected to an inlet pipe 27,
which supplies the refrigerant 19. The both ends of the upper
header tank 15 are also closed by end plates 25. One of the both
ends is connected to an outlet pipe 29, which discharges the
refrigerant 19.
[0053] In FIG. 1, the refrigerant 19 supplied from the inlet pipe
27 is distributed to each tube 21 while flowing through a not-shown
refrigerant distribution passage and a refrigerant passage of the
lower header tank 13 and passes within each tube 21. During this
time, a not-shown heat exchange medium such as cooling air flows
among the tubes 21 and fins 23 of the heat exchanger core 17. The
heat exchange medium exchanges heat with the refrigerant 19 passing
within each tube of the heat exchanger core 17. Flows of the
refrigerant 19 are joined together within the upper header tank 15
and then discharged through the outlet pipe 29 to the outside.
[0054] In the embodiment, the refrigerant 19 is supplied to the
lower header tank 13 and passes within the heat exchanger 11. The
heat exchanger 11, in which flows of the refrigerant 19 are joined
together within the upper header tank 15 and discharged to the
outside, is described. The path through which the refrigerant 19
flows is not limited to that of the embodiment and may be anther
path. For example, the refrigerant 19 may be supplied to the upper
header tank 15 and passed within the heat exchanger 17. Such flows
of the refrigerant 19 may be then joined together in the lower
header tank 13 and discharged to the outside.
[0055] Next, a description is given of structures of the lower and
upper header tanks 13 and 15.
[0056] FIG. 2 is a cross-sectional view along a line II-II of FIG.
1 and shows a structure of the lower header tank 13. The lower
header tank 13 includes a lower tank upper 31, a lower tank lower
33, and a plate 35.
[0057] The lower tank upper 31 as a tank constituent member is
shaped to have a square U-shaped section by bending a plate at both
ends. Flat part thereof includes tube insertion holes 31a for
connection of the tubes 21. The tube insertion holes 31a are formed
at regular intervals in a longitudinal direction.
[0058] The lower tank lower 33 as a tank constituent member
includes a refrigerant distribution groove 33A with a U-shaped
section, which is shaped by pressing center part of a plate
material. The peripheral wall of the refrigerant distribution
groove 33A includes refrigerant communication holes 33a and 33b,
which are formed along the longitudinal direction. Herein, the
communication holes 33a allow passage of gas of the refrigerant.
The communication holes 33a are positioned in upper part in the
direction of gravity when the refrigerant is flown within the lower
header tank 13. The communication holes 33b allow passage of liquid
of the refrigerant. The communication holes 33b are positioned in
lower part in the direction of gravity. Refrigerant such as carbon
dioxide is fed to the header tank with gas and liquid phases being
mixed. The communication holes 33a and 33b, which are arranged as
shown in FIG. 2, efficiently discharge the gas and liquid of the
refrigerant, respectively.
[0059] FIG. 3 is a cross-sectional view along a line III-III of
FIG. 2, showing a positional relation among the tubes 21 and
communication holes 33a and 33b. The communication holes 33a and
33b are positioned so as to fully or partially match the tube
insertion holes 31a in the longitudinal direction of the header
tank or in a plan view thereof. Half or more of sectional areas of
the communication holes 33a and 33b only needs to overlap a
thickness range t of tube width. Such arrangement allows the
refrigerant having passed through the communication holes 33a and
33b to efficiently flow into tubes 21. In this embodiment, the
communication holes 33a are provided at the top of the refrigerant
distribution groove 33A and on both sides thereof, but the number
of the communication holes may be properly determined. For example,
the communication hole may not be provided at the top the
communication holes but provided only on the both sides of the
top.
[0060] As shown in FIG. 2, the bottom face of the lower tank lower
33 includes a step portion 33B. The plate 35 is embedded in the
step portion 33B to close the opening of the refrigerant
distribution groove 33A, thus forming a refrigerant distribution
passage 37 within the tank.
[0061] Furthermore, the lower tank lower 33 is bent at both ends to
have a square C-shaped cross section. The both ends thereof
individually include flanges 33C for positioning of the tubes 21.
Each tube 21 may be positioned by setting width between both ends
of the lower tank lower 33 according to the tube width and abutting
the ends of the tubes 21 on the both ends of the lower tank lower
33.
[0062] As shown in FIG. 2, the lower tank upper 31, lower tank
lower 33, and plate 35 are combined and brazed to be joined into
the lower header tank 13 having a tubular shape with a square
section. The refrigerant distribution passage 37, which
communicates in the longitudinal direction within the tank, and a
refrigerant passage 39, through which the refrigerant distributed
from the refrigerant distribution passage 37 flows, are formed.
[0063] FIG. 4 is a cross-sectional view along III-III of FIG. 1,
showing the structure of the upper header tank 15. The upper header
tank 15 includes an upper tank upper 41 and an upper tank lower
43.
[0064] The upper tank upper 41 as a tank constituent member is
shaped to have a square C-shaped section by bending both ends of a
plate material. The both ends include flanges 41A for positioning
of the tubes 21. The upper tank lower 43 as a tank constituent
member is shaped to have a square U-shaped section also by bending
both ends of a plate material. Flat part thereof includes tube
insertion holes 43a for connection of the tubes 21. The tube
insertion holes 43a are formed at regular intervals in the
longitudinal direction.
[0065] The upper tank upper 41 and upper tank lower 43 are combined
and brazed to be joined into the upper header tank 15 having a
tubular shape with a square section. In the upper header tank 15, a
refrigerant passage 45, which communicates along the longitudinal
direction within the tank, is thus formed.
[0066] The lower and upper header tanks 13 and 15 are arranged to
face to each other as shown in FIG. 1 and individually connected to
the heat exchanger core 17, thus completing the heat exchanger 11.
When the refrigerant 19 is supplied from the inlet pipe 27 to the
heat exchanger 11, the refrigerant 19 flows through the refrigerant
distribution passage 37, which is formed in the lower header tank
13, to be introduced to the back of the tank. During this time, the
refrigerant 19 is discharged through the individual communication
holes 33a and 33b, which are positioned along the longitudinal
direction of the refrigerant distribution groove 33A, and equally
distributed to each tube 21.
[0067] In the lower header tank 13, the refrigerant distribution
groove 33A is formed in the lower tank lower 33 and provided with
the communication holes 33a and 33b. Moreover, the opening thereof
is closed with the plate 35 to form the refrigerant distribution
passage 37. Such a structure eliminates the need to manufacture a
refrigerant distribution pipe, a holding plate, and the like as
separate components, thus reducing component cost. Such a structure
eliminates the need for a process to attach the refrigerant
distribution pipe, holding plate, and the like to the inside of the
tank, thus reducing assembly cost. Accordingly, the lower header
tank 13 has the same function as a header tank including the
refrigerant distribution pipe inside while further reducing
manufacturing cost.
[0068] The integration of the refrigerant distribution groove 33A
and lower tank lower 33 prevents occurrence of distortion in the
refrigerant distribution groove 33A due to the temperature
difference during the brazing and prevents reduction of the
distribution efficiency due to the distortion within the tank as is
observed in the refrigerant distribution pipe.
Second Embodiment
[0069] Next, a description is given of a structure of a lower
header tank 73 according to a second embodiment. Hereinafter,
portions equivalent to those of the first embodiments are indicated
by same reference numerals, and redundant descriptions of the
structure and operational effects are properly omitted.
[0070] FIG. 5 is a cross-sectional view showing a structure of the
lower header tank 73, which corresponds to a cross-sectional view
along II-II of FIG. 1. This lower header tank 73 includes a lower
tank upper 51 and a lower tank lower 53.
[0071] The lower tank upper 51 as a tank constituent member is
shaped to have a square U-shaped section by bending both ends of a
plate material. The flat part thereof includes tube insertion holes
51a for connection of tubes 21. The tube insertion holes 51a are
formed at regular intervals along the longitudinal direction. The
lower tank lower 53 is shaped to have a Q-shaped section by bending
(or extruding) center part of a plate material, thus integrally
forming a refrigerant distribution portion 53A having a circular
section with the lower tank lower 53. A support potion 55 supports
between the refrigerant distribution portion 53A and the body of
the lower tank lower 53. Since this support portion 55 has a
structure in which portions of the plate material are laid on each
other by bending or the like, the support portion 55 may be
separated to form gap during brazing. As shown in FIG. 6,
therefore, the support portion 55 is caulked at predetermined
positions to form joint portions 55A. The joint portions 55A
temporarily join the portions of the plate material laid on each
other to prevent the separation of the plate material, thus
improving the brazing properties.
[0072] The refrigerant distribution portion 53A includes
refrigerant communication holes 53a and 53b along the longitudinal
direction. The communication holes 53a thereof allow passage of
refrigerant in gas phase. The communication holes 53a are
positioned in upper part in the direction of gravity when the
refrigerant is flown within the lower header tank 73. The
communication holes 53b allow passage of refrigerant in liquid
phase and are positioned in lower part in the direction of
gravity.
[0073] The lower tank lower 53 are bent at the both ends and shaped
to have a square C-shaped section. The both ends individually
include flange portions 53C for positioning of the tubes 21.
[0074] This lower tank upper 51 and lower tank lower 53 are
combined as shown in FIG. 5 and brazed to be joined into the lower
header tank 73 having a tubular shape with a square section. This
lower header tank 73 includes the refrigerant distribution passage
57, which communicates in the longitudinal direction within the
tank, and a refrigerant passage 59, through which the refrigerant
distributed from the refrigerant distribution passage 57 is flown,
and equally distributes externally supplied refrigerant to each
tube 21.
[0075] In this lower header tank 73, the lower tank lower 53 and
the refrigerant distribution portion 53A with a substantially
circular section are integrally formed, and the refrigerant
distribution portion 53A is provided with the refrigerant
communication holes 53a and 53b. This structure eliminates the need
to manufacture the refrigerant distribution pipe, holding plate,
and plate as separate components, thus reducing component cost.
This structure eliminates the need for a process to attach the
refrigerant distribution pipe, holding plate, and the like to the
inside of the tank, thus reducing assembly cost. Accordingly, the
lower header tank 73 has the same function as that of the header
tank including the refrigerant distribution pipe inside while
further reducing the manufacturing cost. In this embodiment, the
communication holes 53a are provided at the top of the refrigerant
distribution portion 53A and on both sides thereof, but the number
of communication holes may be properly determined. For example, the
communication holes may not be provided at the top the
communication holes but provided only on the both sides of the
top.
[0076] Integration of the lower tank lower 53 and refrigerant
distribution portion 53A prevents occurrence of distortion in the
refrigerant distribution portion 53A due to the temperature
difference during brazing and prevents reduction of the
distribution efficiency due to the distortion within the tank as is
observed in the refrigerant distribution pipe.
[0077] The support portion 55 of the structure in which the
portions of the plate material are laid on each other includes the
joint portions 55A formed by caulking. This structure temporarily
joins the portions of the plate material laid on each other in the
support portion 55 and prevents separation of the plate material to
improve the brazing properties.
Third Embodiment
[0078] FIG. 7 is a cross-sectional view showing a structure of a
lower header tank 83 according to a third embodiment, which
corresponds to a cross-sectional view along II-II of FIG. 1. The
lower header tank 83 is formed into a tubular shape with a square
section by bending a single plate material or a single pipe
material (in the case of the plate material, joining the seam after
bending). Flat part in the upper face includes tube insertion holes
61a for connection of the tubes 21. The tube insertion holes 61a
are formed at regular intervals in the longitudinal direction. The
center part in the lower face is shaped to have a Q-shaped section,
thus integrally forming a refrigerant distribution portion 63A with
a circular section with the body of the lower header tank 83.
[0079] The refrigerant distribution portion 63A includes a
plurality of refrigerant communication holes 63a and 63b in the
longitudinal direction. Among these, the communication holes 63a
allow passage of refrigerant in gas phase and are positioned in
upper part in the direction of gravity when the refrigerant is
flown within the lower header tank 83. The communication holes 63b
allow passage of refrigerant in liquid phase and are positioned in
lower part in the direction of gravity.
[0080] The lower header tank 83 is formed into a tubular shape with
a square section by bending a single plate material or a pipe
material. This lower header tank 83 includes a refrigerant
distribution passage 67, which communicates in the longitudinal
direction within the tank, and a refrigerant passage 69, through
which the refrigerant distributed from the refrigerant distribution
passage 67 flows, and equally distributes the externally supplied
refrigerant to each tube 21.
[0081] A support portion 65 supports between the refrigerant
distribution portion 63A and the body of the lower header tank 61.
The support portion 65 is caulked at predetermined positions to
form same joints as that in FIG. 6 (not shown) so that the portions
laid on each other are not separated to form a gap during
brazing.
[0082] In the lower header tank 83, the lower tank upper and lower
tank lower are integrally formed, and the body of the lower header
tank 83 and the refrigerant distribution portion 63A with a
substantially circular section are integrally formed. Furthermore,
the refrigerant holes 63a and 63b are provided for this refrigerant
distribution portion 63A. This structure eliminates the need to
manufacture not only the refrigerant distribution pipe, holding
plate, and plate but also the lower tank upper and lower tank lower
as separate components, thus reducing the number of components. The
component cost can be therefore reduced. This structure eliminates
the need for a process to attach the refrigerant distribution pipe,
holding plate, and the like to the inside of the tank, thus
reducing assembly cost. Accordingly, the lower header tank 83 has
the same function as that of the header tank including the
refrigerant distribution pipe inside while further reducing the
manufacturing cost. In this embodiment, the communication holes 63a
are provided at the top of the refrigerant distribution portion 53A
and on both sides thereof, but the number of communication holes
may be properly determined. For example, the communication holes
may not be provided at the top the communication holes but provided
only on the both sides of the top.
[0083] Integration of the lower tank lower 83 and refrigerant
distribution portion 63A prevents occurrence of distortion in the
refrigerant distribution groove 33A due to the temperature
difference during brazing and prevents reduction of the
distribution efficiency due to the distortion within the tank as is
observed in the refrigerant distribution pipe.
[0084] The support portion 65 of the structure in which portions of
the plate material are laid on each other is subjected to caulking
to include the joint portions 55A as shown in FIG. 6. This
structure temporarily joins the portions of the plate material laid
on each other in the support portion 65 and prevents separation of
the plate material, thus improving the brazing properties.
Fourth Embodiment
[0085] As shown in FIG. 8, a header tank 93A includes a first tank
51B with a U-shaped cross section. The header tank 93A includes a
second tank 53B, which is joined to the first tank 51B. The first
and second tanks 51B and 53B form a refrigerant passage 59
inside.
[0086] The second tank 53B is composed of a single metal sheet. The
second tank 53B includes sheet edge portions 53c and 53d each
having an L-shaped section. The sheet edge portions 53c and 53d are
combined to form a U-shaped outer wall. Side edges 53c1 and 53d1 of
the sheet edge portions 53c and 53d are joined with side edges 51c
and 51d of the first tank 51B, respectively.
[0087] The second tank 53B includes a support portion 55 formed by
joining the two sheets extending from the sheet end portions 53c
and 53d. The support portion 55 includes joint portions 55B shown
in FIG. 9. In each joint portion 55B, the two plates laid on each
other are punched to be caulked. This punching forms a first hollow
protrusion 55c in one of the sheets and forms a second hollow
protrusion 55d, which is fit in the first hollow protrusion 55c, in
the other sheet. Such temporary joint by caulking prevents
separation of the sheets in the support portion 55 and prevents
occurrence of gap therebetween, thus improving the brazing
properties.
[0088] The second tank 53 includes a distribution pipe 53e as a
refrigerant distribution portion 53A, which is continuous to each
sheet of the support portion 55. The distribution pipe 53e extends
in the longitudinal direction within the refrigerant passage 59 to
define the refrigerant distribution passage 57 within the same.
[0089] The distribution pipe 53e includes communication holes 53f
and 53g spaced apart at regular intervals in the longitudinal
direction. The communication holes 53f and 53g connect the
refrigerant distribution passage 57 and refrigerant passage 59. The
communication holes 53f have a diameter of, for example, 0.6 mm,
and the communication holes 53g have a diameter of, for example,
1.0 mm. The communication holes 53f are positioned at three to five
o'clock clockwise or counterclockwise with the support portion 55
being set at 0 o'clock. The communication holes 53g are positioned
at 0 to three o'clock clockwise or counterclockwise with the
support portion 55 being set as 0 o'clock. As shown in FIG. 10,
when width t of each tube 21 is laterally projected onto the
distribution pipe 53e and the longitudinal range thereof is
indicated by R1, the communication holes 53f are positioned so that
half or more of the sectional area thereof overlaps the range R1.
In other words, each communication holes 53f only needs to
partially match the range R1 in terms of the longitudinal
position.
[0090] According to this embodiment, integration of the
distribution pipe 53e and header tank 93A increases the heat
transfer efficiency during baking and reduces the temperature
difference between the distribution pipe 53e and header tank 93A
during heating or cooling. Such a reduced temperature difference
reduces differences in expansion and shrinkage and eliminates
distortion of the distribution pipe 53e.
[0091] The integration of the distribution pipe 53e and header tank
93A reduces the numbers of components and assembly steps, thus
reducing manufacturing cost.
[0092] The header tank 93 may be shaped into a tank shape by
bending a single metal sheet.
Fifth Embodiment
[0093] With reference to FIG. 11, a header tank of this embodiment
includes a similar structure to the fourth embodiment and is
characterized by joint portions 55C.
[0094] Each joint portion 55C includes a caulking hole 55a, which
is formed in one of the sheets of the support portion 55. The joint
portion 55C includes a protrusion 55b, which protrudes from the
other sheet of the support portion 55. The protrusion 55C is fit
into a caulking hole 55a. The tip of the protrusion 55b includes a
flange or a ring-shaped stopper 55b1 extending to the outer edge of
the caulking hole 55a. The stopper 55b1 prevents separation of the
sheets of the support portion 55.
[0095] Next, a description is given of a method of manufacturing
the header tank.
[0096] The both side edge portions of one metal sheet are bent to
face to each other, thus forming the first tank with a square
U-shaped section (see the first tank 51B of FIG. 8).
[0097] A description is given of a method of manufacturing the
second tank 53D.
[0098] With reference to FIG. 13, a metal sheet 101 as a raw
material is a clad material with a wax layer on the surface
thereof.
[0099] The sheet 101 includes a center portion 101a extending from
a centerline C1 toward the both side edges. The sheet 101 includes
edge portions 101b and 101c extending from the both side edges
toward the centerline C1. The sheet 101 includes middle portions
101d and 101e between the center portion 101a and the edge portions
101b and 101c, respectively.
[0100] With reference to FIG. 14A, a description is given of a
first step. The first step uses a first table 111 and a second
table 113. The first table 111 includes first processing holes
111a, 111b, 111c, and 111d, through which four punches 115a, 115b,
115c, and 115d pass, respectively. The second table 113 similarly
includes second processing holes 113a, 113b, 113c, and 113d
positioned to match the first processing holes 111a to 111d,
respectively.
[0101] The sheet 101 is placed on the first table 111 and centered
with respect to the first table 111. The second table 113 is placed
on the sheet 101 to place the sheet 101 between the first and
second tables 111 and 113. The punches 115a to 115d are inserted
from the first processing holes 111a to 111d of the first table 111
to pierce the center portion 101a of the sheet 101 with a
predetermined distance apart from the centerline C1 and enter the
second processing holes 113a to 113d of the second table 113. With
such piercing, four holes 101a1, 101a2, 101a3, and 101a4 are opened
in the sheet 101. Among these holes, the two holes 101a1 and 101a2
correspond to the communication holes 53g. The two holes 101a3 and
101a4 correspond to the communication holes 53f.
[0102] With reference to FIG. 14B, a description is given of a
second step. The second step uses a first press die 117 and a
second press die 119. The first press die 117 includes protrusion
portions 117a and 117b at both side edges. The first press die 117
includes a recess portion 117c between the protrusion portions 117a
and 117b. The second press die 119 includes arms 119a and 119b
extending from both side edges. The second press die 119 includes a
protrusion portion 119c in center part. The second press die 119
includes recess portions 119d and 119e between the protrusion
portion 119c and the arms 119a and 119b, respectively.
[0103] The sheet 101 is placed on the first press die 117. The
second press die 119 is moved down and pressed against the sheet
101 placed on the first press die 117. The arms 119a and 119b of
the second press die 119 bend the edge portions 101b and 101c of
the sheet 101 at right angles to press the same against the side
walls of the first press die 117. The protrusion portion 119c of
the second press die 119 dents the center portion 101a of the sheet
101 and press the same against the recess portion 117c of the first
press die 118. The protrusion portions 117a and 117b of the first
press die 117 and the recess portions 119d and 119e of the second
press die 119 hold the middle portions 101d and 101e
therebetween.
[0104] With reference to FIG. 14C, a description is given of a
third step. The third step uses a processing table 121, a press
tool 123, and a punch tool 125. The processing table 121 has a
similar structure to that of the first press die 117 and includes
first and second protrusion portions 121a and 121b at both side
edges. The first protrusion portion 121a includes a hole 121c, into
which the punch tool 125 is inserted. The second protrusion portion
121b includes a protrusion 121d thereon.
[0105] The sheet 101 is placed on the upper face of the processing
table 121. The punch tool 125 pierces the middle portion 101d on
the protrusion portion 121a to open the hole 101f in the middle
portion 101d. This hole 101f corresponds to the caulking hole 55a.
A recess 123a of the press tool 123 is pressed against the middle
portion 101e on the protrusion 121d of the protrusion portion 121b
to form a protrusion 101g in the middle portion 101e. This
protrusion 101g corresponds to the protrusion 55b. The protrusion
101g and hole 101f are formed just before a fifth step, or a
caulking step, thus increasing positional accuracy.
[0106] With reference to FIG. 14D, a description is give of a
fourth step. The fourth step uses a first press die 127 and a
second press die 129. The first press die 127 includes a recess
portion 127b with a semicircular cross section. The second press
die 129 includes a cuboid die 129a and a cylindrical die 129b at an
end of the cuboid die 129a.
[0107] The sheet 101 is placed on the processing table 127. The
second press die 129 is moved down to press the center portion 101a
of the sheet 101 against the recess portion 127b and shape a lower
half 101a1 of the center portion 101a so as to have a semicircular
section. The upper half of the center portion 101 and the middle
portions 101d and 101e are pressed against side walls of the cuboid
die 129a.
[0108] With reference to FIG. 14E, a description is given of a
fifth embodiment. The fifth embodiment uses a first press die 131,
second press dies 133a and 133b, and a third press die 135. The
first press die 131 includes a recess portion 131b with a
semicircular section in a top face 131a. The second press dies 133a
and 133b include recess portions 133a1 and 133b1 with quarter
circular sections, respectively. The third press die 135 includes
guides 135a and 135b extending from the both side edges.
[0109] The lower half of the middle portion 101a of the sheet 101
is set in the recess portion 131b of the first press die 131. The
second press dies 133a and 133b are applied to the upper half of
the center portion 101a and the middle portions 101d and 101e. The
upper half of the center potion 101a is brought into contact with
the recess portions 133a1 and 133b1. The middle portions 101d and
101e come into contact with each other, and the protrusion 101g of
the middle portion 101e is inserted into the hole 101e of the
middle portion 101d. The third press die 135 is moved down toward
the both edge portions 101b and 101c of the sheet 101 on the second
dies 133a and 133b. The guides 135a and 135b slide on the side
walls of the second press dies 133a and 133b to press the second
press dies 133a and 133b to the sheet 101. The second press dies
133a and 133b pressure-bond the middle portions 101d and 101e and
crushes and extends the tip of the protrusion 101g into a ring
shape (caulking). The ring-shaped tip corresponds to the stopper
55b1. The recess portions 133a1 and 133b1 shape the upper half of
the center portion 101a into an arc.
[0110] With reference to FIG. 14F, a description is given of a
sixth step. The sixth step uses a first press die 137 and a second
press die 139. The first press die 137 includes two components
combined.
[0111] The components of the first press die 137 individually
include convex outer walls 137a1 and 137a2. The first press die 137
includes a recess of a combination of a space 137c with a
rectangular section and a space 137b with a circular section. The
second press die 139 includes a recess portion 139a. The recess
portion 139a includes concave inner walls 139a1 and 139a2 on both
sides of the centerline C1.
[0112] The center portion 101a of the sheet 101 is set in the space
137b, and the middle portions 101d and 101e are set in the space
137c. The both edge portions 101b and 101c of the sheet 101 are set
on the outer walls 137a1 and 137a2.
[0113] The second press die 139 is moved down to the first press
die 137. The inner wall 139a1 and 139a2 press the both edge
portions 101b and 101c of the sheet 101 against the outer walls
137a1 and 137a2. With such a press, the both edge portions 101b and
101c are bent toward the center potion 101a.
[0114] Thereafter, the middle portions 101d and 101e of the sheet
101 are brazed to complete the second tank 53D. The wax material
may be applied to the middle portions 101d and 101e after the sixth
step.
[0115] The both side edges of the first tank and second tank 53D
are brazed to complete the header tank.
[0116] According to this embodiment, bringing the middle portions
101d and 101e of the sheet 101 into contact for caulking suppresses
the separation of the sheets of the support portion 55 before
baking and prevents bad brazing.
[0117] The protrusion 55b between the sheets of the support portion
55 stabilizes the fluidity of the wax to improve the brazing
properties. In other words, the members having a contact point
(joint) allows the wax material to easily flow on the entire
contact surface.
Sixth Embodiment
[0118] With reference to FIGS. 15 and 16, a description is given of
a header tank 93B according to this embodiment.
[0119] This header tank 93B is characterized by a second tank 53E.
Specifically, the second tank 53E includes communication holes 53p,
for example, with an equivalent diameter of 1.0 mm or more in the
support portion 55. The communication holes with an equivalent
diameter of 1.0 mm or more are holes having an opening area
equivalent to a circular hole with a diameter of 1.0 mm or more.
The communication holes 53p are formed at regular intervals in the
longitudinal direction. The distribution pipe 53e further includes
communication holes 53g between the communication holes 53f and
53p.
[0120] As shown in FIG. 16, the communication holes 53p communicate
with refrigerant passages 59 on both sides of the support portion
55 and allow transfer of the refrigerant in liquid phase between
the refrigerant passages 59.
[0121] With reference to FIGS. 17 and 18, a description is given of
a header tank 93C of another aspect. This header tank 93C is
characterized by a second tank 53F. Specifically, the second tank
53F includes communication holes 53q positioned so as to extend
from the support portion 55 to the distribution pipe 57. These
communication holes 53q also have a function to discharge liquid
refrigerant from the distribution pipe 57, so that holes to
discharge liquid refrigerant are eliminated.
[0122] According to the aforementioned embodiment, the
communication holes 53p and 53q, respectively, keep equal liquid
levels of the liquid refrigerant on each side of the support
portion 55 within the header tanks 53E and 53F and thus stabilize
the performance of the header tanks 53E and 53F.
[0123] This structure prevents accumulation of lubricant oil of a
compressor and protects the compressor.
[0124] This structure achieves weight reduction of the header tanks
53E and 53F.
INDUSTRIAL APPLICABILITY
[0125] The header tank of the heat exchanger of the present
invention is useful in terms of application to vehicle air
conditioners such as compressors and evaporators.
* * * * *