U.S. patent application number 13/214298 was filed with the patent office on 2012-02-23 for evaporator with cool storage function.
This patent application is currently assigned to SHOWA DENKO K.K.. Invention is credited to Naohisa Higashiyama, Takashi Hirayama, Osamu Kamoshida.
Application Number | 20120042687 13/214298 |
Document ID | / |
Family ID | 45557489 |
Filed Date | 2012-02-23 |
United States Patent
Application |
20120042687 |
Kind Code |
A1 |
Kamoshida; Osamu ; et
al. |
February 23, 2012 |
EVAPORATOR WITH COOL STORAGE FUNCTION
Abstract
An evaporator with a cool storage function includes a cool
storage material container disposed at least one of air-passing
clearances formed between adjacent refrigerant flow tubes, and fins
disposed in air-passing clearances on opposite sides of the cool
storage material container. The cool storage material container
includes a container body portion joined to the corresponding
refrigerant flow tubes, and an outward extending portion which
extends from the front edge of the container body portion and
projects frontward in relation to the refrigerant flow tubes. Each
of the fins has a fin body portion joined to the corresponding
refrigerant flow tubes, and an outward extending portion which
extends from the front edge of the fin body portion body and
projects frontward in relation to the refrigerant flow tubes. The
outward extending portions of the fins are brazed to opposite sides
of the outward extending portion of the cool storage material
container.
Inventors: |
Kamoshida; Osamu;
(Oyama-shi, JP) ; Higashiyama; Naohisa;
(Oyama-shi, JP) ; Hirayama; Takashi; (Oyama-shi,
JP) |
Assignee: |
SHOWA DENKO K.K.
Tokyo
JP
|
Family ID: |
45557489 |
Appl. No.: |
13/214298 |
Filed: |
August 22, 2011 |
Current U.S.
Class: |
62/524 |
Current CPC
Class: |
F28D 20/02 20130101;
F28D 2020/0013 20130101; F25B 39/02 20130101; F28D 1/05391
20130101; F28D 2021/0085 20130101; Y02E 60/14 20130101; Y02E 60/145
20130101; F25B 2400/24 20130101 |
Class at
Publication: |
62/524 |
International
Class: |
F25B 39/02 20060101
F25B039/02 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 23, 2010 |
JP |
2010-185876 |
Nov 12, 2010 |
JP |
2010-253602 |
Dec 13, 2010 |
JP |
2010-276604 |
Dec 24, 2010 |
JP |
2010-287770 |
Feb 10, 2011 |
JP |
2011-027165 |
Claims
1. An evaporator with a cool storage function in which a plurality
of vertically extending flat refrigerant flow tubes are disposed in
parallel such that their width direction coincides with an
air-passing direction and they are spaced from one another,
air-passing clearances are formed such that each air-passing
clearance is provided between adjacent refrigerant flow tubes, a
cool storage material container filled with a cool storage material
is disposed in at least one of the air-passing clearances, and
outer fins are disposed in the remaining air-passing clearances,
wherein the cool storage material container includes a container
body portion joined to the corresponding refrigerant flow tubes,
and an outward extending portion which extends from a
downstream-side edge of the container body portion and projects
downstream in relation to the refrigerant flow tubes; an outer fin
disposed in an air-passing clearance adjacent to the air-passing
clearance in which the cool storage material container is disposed
has a fin body portion joined to the corresponding refrigerant flow
tubes, and an outward extending portion which extends from a
downstream-side edge of the fin body portion body and projects
downstream in relation to the refrigerant flow tubes; and the
outward extending portion of the outer fin is in contact with a
corresponding side surface of the outward extending portion of the
cool storage material container.
2. An evaporator with a cool storage function according to claim 1,
wherein each of the outer fins disposed in air-passing clearances
located on opposite sides of the air-passing clearance in which the
cool storage material container is disposed has the fin body
portion and the outward extending portion; and the outward
extending portions of the outer fins are in contact with the
opposite side surfaces of the outward extending portion of the cool
storage material container.
3. An evaporator with a cool storage function according to claim 1,
wherein the outward extending portion of the cool storage material
container bulges over the entire length in the vertical direction,
the outward extending portion bulging outward in relation to the
container body portion with respect to a direction along which the
refrigerant flow tubes are arrayed; and the outward extending
portion has a dimension in a thickness direction thereof greater
than a dimension of the container body portion in a thickness
direction thereof.
4. An evaporator with a cool storage function according to claim 1,
wherein the outward extending portion of the cool storage material
container has a base portion whose dimension in a thickness
direction thereof is equal to a dimension of the container body
portion in a thickness direction thereof, and a plurality of
projecting portions which are provided on the base portion such
that the projecting portions are spaced from one another in the
vertical direction and which bulge outward from the base portion
with respect to a direction along which the refrigerant flow tubes
are arrayed.
5. An evaporator with a cool storage function according to claim 1,
wherein the outward extending portion of the corresponding outer
fin is brazed to the outward extending portion of the cool storage
material container.
6. An evaporator with a cool storage function according to claim 1,
wherein the cool storage material container is composed of two
metal plates whose peripheral edge portions are joined together;
and the container body portion and the outward extending portion of
the cool storage material container are provided by means of
outward bulging at least one of the two metal plates.
7. An evaporator with a cool storage function according to claim 1,
wherein an inner fin extending from the container body portion to
the outward extending portion of the cool storage material
container is disposed in the cool storage material container.
8. An evaporator with a cool storage function according to claim 7,
wherein the inner fin assumes a corrugated shape, and has crest
portions extending in the air-passing direction, trough portions
extending in the air-passing direction, and connection portions
connecting the crest portions and the trough portions.
9. An evaporator with a cool storage function according to claim 7,
wherein the inner fin assumes a staggered shape, and is composed of
a plurality of corrugated strips, each of which has crest portions
extending in the air-passing direction, trough portions extending
in the air-passing direction, and connection portions connecting
the crest portion and the trough portion, the corrugated strips
being arranged in the air-passing direction and integrally
connected with one another such that the crest portions and the
trough portions of one of two strips adjacent to each other in the
air-passing direction are positionally shifted in the vertical
direction from those of the other strip.
10. An evaporator with a cool storage function according to claim
1, wherein the container body portion of the cool storage material
container is brazed to the corresponding refrigerant flow tubes;
and grooves are formed in portions of outer surfaces of the
container body portion of the cool storage material container,
which portions are brazed to the corresponding refrigerant flow
tubes.
11. An evaporator with a cool storage function according to claim
10, wherein the grooves formed in each of the portions of the outer
surfaces of the container body portion of the cool storage material
container, which portions are brazed to the corresponding
refrigerant flow tubes, form a grid.
12. An evaporator with a cool storage function according to claim
1, comprising a plurality of refrigerant flow tube sets each
including a plurality of flat refrigerant flow tubes disposed such
that their width direction coincides with the air-passing direction
and they are spaced from one another in the air-passing direction;
and the container body portion of the cool storage material
container is disposed to extend over all the refrigerant flow tubes
of the corresponding set, and is joined to the refrigerant flow
tubes.
13. An evaporator with a cool storage function according to claim
1, wherein the container body portion of the cool storage material
container has an internal-volume reducing portion which is formed
through partial inward deformation of a wall of the cool storage
material container and which reduces an internal volume of the cool
storage material container.
14. An evaporator with a cool storage function according to claim
13, wherein the internal-volume reducing portion of the container
body portion of the cool storage material container is configured
to bulge due to an increase in internal pressure when the
internal-volume reducing portion is exposed to a high temperature
exceeding a temperature range of use environment.
15. An evaporator with a cool storage function according to claim
1, wherein a cool storage material charging ratio, which is the
ratio of the volume of the charged cool storage material to the
internal volume of the cool storage material container is 70 to
90%.
16. An evaporator with a cool storage function according to claim
15, wherein the cool storage material charging ratio is 70 to
80%.
17. An evaporator with a cool storage function according to claim
1, wherein each of the refrigerant flow tubes in thermal contact
with the cool storage material container has a plurality of
refrigerant flow channels which are arranged in the width direction
of the refrigerant flow tube and are separated from one another by
partitions; and a relation 0.1.ltoreq.t.ltoreq.0.4 and a relation
0.64.ltoreq.h/H.ltoreq.0.86 are satisfied, where t represents a
thickness (mm) of each partition, h represents a height (mm) of
each partition, and H represents a tube height (mm), which is a
dimension of each refrigerant flow tube in a thickness direction
thereof.
18. An evaporator with a cool storage function according to claim
17, wherein a relation 0.07.ltoreq.(n.times.t)/W.ltoreq.0.31 is
satisfied, where n represents the number of the partitions of each
refrigerant flow tube, and W represents a width (mm) of each
refrigerant flow tube.
19. An evaporator with a cool storage function according to claim
17, wherein the tube height H of each refrigerant flow tube is 12
to 25 mm, and the width W of each refrigerant flow tube is 1.3 to
3.0 mm.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to an evaporator with a cool
storage function for use in a car air conditioner for a vehicle in
which an engine serving as a drive source for a compressor is
temporarily stopped when the vehicle is stopped.
[0002] In the present specification and appended claims, the upper
and lower sides of FIG. 1 will be referred to as "upper" and
"lower," respectively.
[0003] In recent years, in order to protect the environment and
improve fuel consumption of automobiles, there has been proposed an
automobile designed to automatically stop the engine when the
automobile stops, for example, so as to wait for a traffic light to
change.
[0004] Incidentally, an ordinary car air conditioner has a problem
in that, when an engine of an automobile in which the air
conditioner is mounted is stopped, a compressor driven by the
engine is stopped, and supply of refrigerant to an evaporator
stops, whereby the cooling capacity of the air conditioner sharply
drops.
[0005] As one measure to solve such a problem, imparting a cool
storage function to the evaporator has been considered, to thereby
enable cooling of a vehicle compartment by making use of cool
stored in the evaporator, when the compressor stops as a result of
stoppage of the engine.
[0006] An evaporator with a cool storage function has been proposed
(see, for example, Japanese Patent No. 4043776). The proposed
evaporator includes a pair of refrigerant header sections disposed
apart from each other, and a plurality of flat refrigerant flow
tubes disposed between the two refrigerant header sections such
that their width direction coincides with an air-passing direction,
and they are spaced from one another in the longitudinal direction
of the refrigerant header sections. Opposite ends of the
refrigerant flow tubes are connected to the two refrigerant header
sections, respectively. The evaporator further includes a plurality
of hollow cool storage material containers disposed such that their
width direction coincides with the air-passing direction. Each of
the cool storage material containers is fixedly provided on one
side of a corresponding refrigerant flow tube and contains a cool
storage material therein. The dimension of each cool storage
material container in the thickness direction thereof is made
uniform over the entirety of the cool storage material container. A
plurality of sets each composed of refrigerant flow tubes and a
cool storage material container are disposed apart from one
another, and a space between adjacent pairs each composed of
refrigerant flow tubes and a cool storage material container serves
as an air-passing clearance. A fin is disposed in the air-passing
clearance, and is joined to the refrigerant flow tubes and the cool
storage material container.
[0007] In the case of the evaporator with a cool storage function
disclosed in the publication, when refrigerant of low temperature
flows through the refrigerant flow tubes, cool is stored in the
cool storage material within the cool storage material
container.
[0008] However, the evaporator with a cool storage function
disclosed in the publication has a problem in that, as compared
with an ordinary evaporator which has the same effective core area
and which does not has a cool storage material container, the
number of refrigerant flow tubes decreases, whereby cooling
performance deteriorates.
[0009] In order to solve the above-mentioned problem of the
evaporator with a cool storage function disclosed in the
publication, the present applicant has proposed an evaporator with
a cool storage function in which a plurality of flat refrigerant
flow tube portions which extend in the vertical direction and whose
width direction coincides with an air-passing direction are
disposed in parallel such that they are spaced apart from one
another; air-passing clearances are formed between adjacent
refrigerant flow tube portions; a cool storage material container
filled with a cool storage material is disposed in each of some
air-passing clearances selected from all the air-passing
clearances, the selected air-passing clearances being not adjacent
to one another; and fins are disposed in the remaining air-passing
clearances (see Japanese Patent Application Laid-Open (kokai) No.
2010-149814).
[0010] However, the evaporator with a cool storage function
disclosed in the publication has the following problem. Effective
ways of increasing the quantity of a cool storage material charging
into a cool storage material container, without changing the size
of the heat exchange core section, to thereby improve cooling
storage performance are increasing the number of cool storage
material containers and increasing all the container heights of the
entire cool storage material containers. However, in either case,
the air passage area of the air-passing clearances decreases, and
air-passing resistance increases.
SUMMARY OF THE INVENTION
[0011] An object of the present invention is to solve the above
problems and to provide an evaporator with a cool storage function
which can restrain an increase in air-passing resistance, as
compared with the evaporator with a cool storage function disclosed
in the publication, while restraining deterioration of cooling
performance.
[0012] To fulfill the above object, the present invention comprises
the following modes.
[0013] 1) An evaporator with a cool storage function in which a
plurality of vertically extending flat refrigerant flow tubes are
disposed in parallel such that their width direction coincides with
an air-passing direction and they are spaced from one another,
air-passing clearances are formed such that each air-passing
clearance is provided between adjacent refrigerant flow tubes, a
cool storage material container filled with a cool storage material
is disposed in at least one of the air-passing clearances, and
outer fins are disposed in the remaining air-passing clearances,
wherein
[0014] the cool storage material container includes a container
body portion joined to the corresponding refrigerant flow tubes,
and an outward extending portion which extends from a
downstream-side edge of the container body portion and projects
downstream in relation to the refrigerant flow tubes;
[0015] an outer fin disposed in an air-passing clearance adjacent
to the air-passing clearance in which the cool storage material
container is disposed has a fin body portion joined to the
corresponding refrigerant flow tubes, and an outward extending
portion which extends from a downstream-side edge of the fin body
portion body and projects downstream in relation to the refrigerant
flow tubes; and
[0016] the outward extending portion of the outer fin is in contact
with a corresponding side surface of the outward extending portion
of the cool storage material container.
[0017] 2) An evaporator with a cool storage function according to
par. 1), wherein each of the outer fins disposed in air-passing
clearances located on opposite sides of the air-passing clearance
in which the cool storage material container is disposed has the
fin body portion and the outward extending portion; and the outward
extending portions of the outer fins are in contact with the
opposite side surfaces of the outward extending portion of the cool
storage material container.
[0018] 3) An evaporator with a cool storage function according to
par. 1), wherein the outward extending portion of the cool storage
material container bulges over the entire length in the vertical
direction, the outward extending portion bulging outward in
relation to the container body portion with respect to a direction
along which the refrigerant flow tubes are arrayed; and the outward
extending portion has a dimension in a thickness direction thereof
greater than a dimension of the container body portion in a
thickness direction thereof.
[0019] 4) An evaporator with a cool storage function according to
par. 1), wherein the outward extending portion of the cool storage
material container has a base portion whose dimension in a
thickness direction thereof is equal to a dimension of the
container body portion in a thickness direction thereof, and a
plurality of projecting portions which are provided on the base
portion such that the projecting portions are spaced from one
another in the vertical direction and which bulge outward from the
base portion with respect to a direction along which the
refrigerant flow tubes are arrayed.
[0020] 5) An evaporator with a cool storage function according to
par. 1), wherein the outward extending portion of the corresponding
outer fin is brazed to the outward extending portion of the cool
storage material container.
[0021] 6) An evaporator with a cool storage function according to
par. 1), wherein the cool storage material container is composed of
two metal plates whose peripheral edge portions are joined
together; and the container body portion and the outward extending
portion of the cool storage material container are provided by
means of outward bulging at least one of the two metal plates.
[0022] 7) An evaporator with a cool storage function according to
par. 1), wherein an inner fin extending from the container body
portion to the outward extending portion of the cool storage
material container is disposed in the cool storage material
container.
[0023] 8) An evaporator with a cool storage function according to
par. 7), wherein the inner fin assumes a corrugated shape, and has
crest portions extending in the air-passing direction, trough
portions extending in the air-passing direction, and connection
portions connecting the crest portions and the trough portions.
[0024] 9) An evaporator with a cool storage function according to
par. 7), wherein the inner fin assumes a staggered shape, and is
composed of a plurality of corrugated strips, each of which has
crest portions extending in the air-passing direction, trough
portions extending in the air-passing direction, and connection
portions connecting the crest portion and the trough portion, the
corrugated strips being arranged in the air-passing direction and
integrally connected with one another such that the crest portions
and the trough portions of one of two strips adjacent to each other
in the air-passing direction are positionally shifted in the
vertical direction from those of the other strip.
[0025] 10) An evaporator with a cool storage function according to
par. 1), wherein the container body portion of the cool storage
material container is brazed to the corresponding refrigerant flow
tubes; and grooves are formed in portions of outer surfaces of the
container body portion of the cool storage material container,
which portions are brazed to the corresponding refrigerant flow
tubes.
[0026] 11) An evaporator with a cool storage function according to
par. 10), wherein the grooves formed in each of the portions of the
outer surfaces of the container body portion of the cool storage
material container, which portions are brazed to the corresponding
refrigerant flow tubes, form a grid.
[0027] 12) An evaporator with a cool storage function according to
par. 1), comprising a plurality of refrigerant flow tube sets each
including a plurality of flat refrigerant flow tubes disposed such
that their width direction coincides with the air-passing direction
and they are spaced from one another in the air-passing direction;
and the container body portion of the cool storage material
container is disposed to extend over all the refrigerant flow tubes
of the corresponding set, and is joined to the refrigerant flow
tubes.
[0028] 13) An evaporator with a cool storage function according to
par. 1), wherein the container body portion of the cool storage
material container has an internal-volume reducing portion which is
formed through partial inward deformation of a wall of the cool
storage material container and which reduces an internal volume of
the cool storage material container.
[0029] 14) An evaporator with a cool storage function according to
par. 13), wherein the internal-volume reducing portion of the
container body portion of the cool storage material container is
configured to bulge due to an increase in internal pressure when
the internal-volume reducing portion is exposed to a high
temperature exceeding a temperature range of use environment.
[0030] 15) An evaporator with a cool storage function according to
par. 1), wherein a cool storage material charging ratio, which is
the ratio of the volume of the charged cool storage material to the
internal volume of the cool storage material container is 70 to
90%.
[0031] 16) An evaporator with a cool storage function according to
par. 15), wherein the cool storage material charging ratio is 70 to
80%.
[0032] 17) An evaporator with a cool storage function according to
par. 1), wherein each of the refrigerant flow tubes in thermal
contact with the cool storage material container has a plurality of
refrigerant flow channels which are arranged in the width direction
of the refrigerant flow tube and are separated from one another by
partitions; and
[0033] a relation 0.1 .ltoreq.t.ltoreq.0.4 and a relation
0.64.ltoreq.h/H.ltoreq.0.86 are satisfied, where t represents a
thickness (mm) of each partition, h represents a height (mm) of
each partition, and H represents a tube height (mm), which is a
dimension of each refrigerant flow tube in a thickness direction
thereof.
[0034] 18) An evaporator with a cool storage function according to
par. 17), wherein a relation 0.0 .ltoreq.(n.times.t)/W.ltoreq.0.31
is satisfied, where n represents the number of the partitions of
each refrigerant flow tube, and W represents a width (mm) of each
refrigerant flow tube.
[0035] 19) An evaporator with a cool storage function according to
par. 17), wherein the tube height H of each refrigerant flow tube
is 12 to 25 mm, and the width W of each refrigerant flow tube is
1.3 to 3.0 mm.
[0036] According to the evaporator with a cool storage function of
any one of pars. 1) to 19), the cool storage material container
includes a container body portion joined to the corresponding
refrigerant flow tubes, and an outward extending portion which
extends from a downstream-side edge of the container body portion
and projects downstream in relation to the refrigerant flow tubes.
Therefore, the quantity of the cool storage material which can be
charged into one cool storage material container can be increased
by an amount corresponding to the internal volume of the outward
extending portion, as compared with the cool storage material
container of the evaporator with a cool storage function disclosed
in the above-described publication. Accordingly, even when the
quantity of the cool storage material charged into the cool storage
material container is increased without changing the size of the
heat change core section, it is unnecessary to increase the number
of the cool storage material containers and all the container
heights of the entire storage material containers. Therefore, as
compared with the evaporator with a cool storage function disclosed
in the above-described publication, a decrease in the air passing
area of the air-passing clearances can be restrained, whereby an
increase in air-passing resistance can be restrained.
[0037] In addition, a plurality of vertically extending flat
refrigerant flow tubes are disposed in parallel such that their
width direction coincides with an air-passing direction and they
are spaced from one another, air-passing clearances are formed such
that each air-passing clearance is provided between adjacent
refrigerant flow tubes, a cool storage material container filled
with a cool storage material is disposed in each of at least some
of all the air-passing clearances which are not adjacent to one
another, and outer fins are disposed in the remaining air-passing
clearances. Therefore, even when the effective core area is made
equal to that of the evaporator with a cool storage function
disclosed in the above-described publication, the number of the
refrigerant flow tubes does not decreases. Accordingly,
deterioration of cooling performance can be restrained.
[0038] Moreover, an outer fin disposed in an air-passing clearance
adjacent to the air-passing clearance in which the cool storage
material container has a fin body portion joined to the
corresponding refrigerant flow tubes, and an outward extending
portion which extends from a downstream-side edge of the fin body
portion body and projects downstream in relation to the refrigerant
flow tubes; and the outward extending portion of the outer fin is
in contact with a corresponding side surface of the outward
extending portion of the cool storage material container. When cool
is stored in the cool storage material within the cool storage
material container upon operation of a compressor, the cool storage
material is cooled by refrigerant flowing through the refrigerant
flow tubes, and is also cooled by air which flows through the
air-passing clearances and whose temperature is lowered. Therefore,
the cool storage material can be cooled efficiently, whereby cool
storage performance is enhanced. Meanwhile, when the compressor
stops as a result of stoppage of an engine, the cool stored in the
cool storage material within the container body portion of the cool
storage material container is transferred to air passing through
the adjacent air-passing clearances via the refrigerant flow tubes
located on the opposite sides of the cool storage material
container, and the cool stored in the cool storage material within
the outward extending portion of the cool storage material
container is transferred from the outward extending portion to the
outer fin joined to one side surface of the outward extending
portion, and then transferred to air passing through the
air-passing clearance in which the outer fin is disposed.
Therefore, cool release performance is enhanced.
[0039] According to the evaporator with a cool storage function of
par. 2), both cool storage performance (performance of storing cool
in the cool storage material within the cool storage material
container when the compressor operates) and cool release
performance (performance of releasing cool from the cool storage
material within the cool storage material container when the
compressor stops) are enhanced further.
[0040] According to the evaporator with a cool storage function of
each of pars. 3) and 4), the quantity of the cool storage material
within the cool storage container can be increased further.
[0041] According to the evaporator with a cool storage function of
par. 4), the heat transfer area between the opposite side walls of
the outward extending portion of the cool storage material
container and the cool storage material within the outward
extending portion increases.
[0042] According to the evaporator with a cool storage function of
par. 6), the cool storage material container can be manufactured
relatively easily.
[0043] According to the evaporator with a cool storage function of
par. 7), an inner fin extending from the container body portion to
the outward extending portion of the cool storage material
container is disposed in the cool storage material container.
Therefore, the cool storage material within the outward extending
portion is also cooled quickly by refrigerant flowing through the
refrigerant flow tubes. Accordingly, the cool storage material
within the cool storage material container can be cooled
efficiently.
[0044] According to the evaporator with a cool storage function of
each of pars. 8) and 9), the cool storage material within the
outward extending portion is cooled more effectively by refrigerant
flowing through the refrigerant flow tubes.
[0045] According to the evaporator with a cool storage function of
each of pars. 10) and 11), a melted flux or melted brazing filler
material becomes more likely to flow through the grooves over the
entire interface between the container body portion of the cool
storage material container and the refrigerant flow tubes.
Therefore, the container body portion of the cool storage material
container and the refrigerant flow tubes can be brazed more
reliably.
[0046] According to the evaporator with a cool storage function of
each of pars. 13) and 14), the container body portion of the cool
storage material container has an internal-volume reducing portion
which is formed through partial inward deformation of a wall of the
cool storage material container and which reduces the internal
volume of the cool storage material container. Therefore, the
internal volume of the cool storage material container decreases as
compared with the case where the internal-volume reducing portion
is not provided. As a result, even when the quantity of the cool
storage material charged into the cool storage material container
is determined to attain a cool storage material charging ratio
suitable for the case where the internal-volume reducing portion is
not provided (e.g., 70 to 90%), the cool storage material exists
even in the vicinity of the upper end of the cool storage material
container. Therefore, cool can be stored even in the vicinity of
the upper end of the cool storage material container. Thus, when
the compressor stops, an increase in the temperature of air flowing
through portions of the air-passing clearances corresponding to the
vicinity of the upper end of the cool storage material container
can be restrained, whereby variation of discharge air temperature,
which is the temperature of air having passed through the
evaporator with a cool storage function, can be restrained.
[0047] Even the evaporator with a cool storage function of par. 13)
or 14) is designed such that within an ordinary temperature range
of use environment (e.g., -40 to 90.degree. C.), the cool storage
material container does not break even when the internal pressure
increases because of a change in the density of the cool storage
material in the liquid phase, and thermal expansion of air
remaining in the cool storage material container. When the cool
storage material container is exposed to a temperature (e.g.,
100.degree. C.) higher than the ordinary temperature range of use
environment, the change in the density of the liquid-phase cool
storage material and the thermal expansion of air remaining in the
cool storage material container become remarkable, whereby the
internal pressure of the cool storage material container increases
excessively. In such a case, the internal-volume reducing portion
of the cool storage material container deforms through bulging,
whereby breakage of the cool storage material container due to an
increase in the internal pressure of the cool storage material
container can be prevented. In addition, since the strength of the
internal-volume reducing portion is lower than that of the
remaining portion, when the cool storage material container is
exposed to a higher temperature, the cool storage material
container breaks at the internal-volume reducing portion, and the
cool storage material leaks. However, since leakage of the cool
storage material occurs at a previously determined location (the
internal-volume reducing portion), the leaked cool storage material
can be coped relatively easily.
[0048] According to the evaporator with a cool storage function of
each of pars. 15) and 16), breakage of the cool storage material
container due to the internal pressure thereof can be prevented
even when the density of the liquid-phase cool storage material
changes and air remaining in the cool storage material container
expands within the temperature range of use environment (e.g., -40
to 90.degree. C.).
[0049] According to the evaporator with a cool storage function of
par. 16), breakage of the cool storage material container due to
the internal pressure thereof within the temperature range of use
environment can be prevented effectively.
[0050] According to the evaporator with a cool storage function of
any one of pars. 17) to 19), when cool is stored, cool is
efficiently transferred from refrigerant flowing through the flow
channels of the refrigerant flow tubes to the opposite side
surfaces of the cool storage material container, and, when cool is
released, the cool stored in the cool storage material within the
cool storage material container efficiently passes through the
refrigerant flow tubes in the tube height direction, whereby both
cool storage performance and cool release performance become
excellent. In addition, cooling performance at the time of ordinary
cooling when the compressor is operating is not sacrificed
[0051] According to the evaporator with a cool storage function of
par. 18), both cool storage performance and cool release
performance become more excellent.
BRIEF DESCRIPTION OF THE DRAWINGS
[0052] FIG. 1 is a partially cut-away perspective view showing the
overall structure of an evaporator with a cool storage function
according to the present invention;
[0053] FIG. 2 is an enlarged sectional view taken along line A-A of
FIG. 1;
[0054] FIG. 3 is an exploded perspective view showing a cool
storage material container of the evaporator with a cool storage
function of FIG. 1;
[0055] FIG. 4 is a graph showing results of computer simulation
calculation performed for determining a cool storage material
charging ratio, which is the ratio of the volume of a charged cool
storage material to the internal volume of the cool storage
material container;
[0056] FIG. 5 is a graph showing results of computer simulation
calculation which is different from that shown in FIG. 4 and is
performed for determining the cool storage material charging ratio,
which is the ratio of the volume of the charged cool storage
material to the internal volume of the cool storage material
container;
[0057] FIG. 6 is a graph showing results of computer simulation
calculation performed for determining the thickness of the
partitions of each refrigerant flow tube;
[0058] FIG. 7 is a graph showing results of computer simulation
calculation which is different from that shown in FIG. 6 and is
performed for determining the thickness of the partitions of each
refrigerant flow tube;
[0059] FIG. 8 is a graph showing results of computer simulation
calculation performed for determining the ratio of the height of
the partitions to a tube height, which is a dimension of each
refrigerant flow tube in the thickness direction thereof;
[0060] FIG. 9 is a graph showing results of computer simulation
calculation which is different from that shown in FIG. 8 and is
performed for determining the ratio of the height of the partitions
to the tube height, which is the dimension of each refrigerant flow
tube in the thickness direction thereof;
[0061] FIG. 10 is an exploded perspective view showing a first
modification of the cool storage material container;
[0062] FIG. 11 is an exploded perspective view showing a second
modification of the cool storage material container; and
[0063] FIG. 12 is an exploded perspective view showing a third
modification of the cool storage material container.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0064] An embodiment of the present invention will next be
described with reference to the drawings. Notably, the same
reference numerals are used throughout the drawings to refer to the
same portions and members, and their repeated descriptions are
omitted.
[0065] In the following description, the downstream side with
respect to an air-passing direction (a direction represented by
arrow X in FIGS. 1 and 2) will be referred to as the "front," and
the opposite side as the "rear." Further, the left-hand and
right-hand sides as viewed rearward from the front side; i.e., the
left-hand and right-hand sides of FIG. 1, will be referred to as
"left" and "right," respectively.
[0066] Furthermore, the term "aluminum" as used in the following
description encompasses aluminum alloys in addition to pure
aluminum.
[0067] FIG. 1 shows the overall configuration of an evaporator with
a cool storage function according to the present invention, and
FIGS. 2 and 3 show the configuration of an essential portion of the
evaporator.
[0068] As shown in FIG. 1, an evaporator with a cool storage
function 1 includes a first header tank 2 and a second header tank
3 formed of aluminum and disposed apart from each other in the
vertical direction such that they extend in the left-right
direction; and a heat exchange core section 4 provided between the
two header tanks 2 and 3.
[0069] The first header tank 2 includes a refrigerant inlet header
section 5 located on the front side (downstream side with respect
to the air-passing direction); and a refrigerant outlet header
section 6 located on the rear side (upstream side with respect to
the air-passing direction) and united with the refrigerant inlet
header section 5. A refrigerant inlet 7 is provided at the right
end of the refrigerant inlet header section 5, and a refrigerant
outlet 8 is provided at right end of the refrigerant outlet header
section 6. The second header tank 3 includes a first intermediate
header section 9 located on the front side, and a second
intermediate header section 11 located on the rear side and united
with the first intermediate header section 9. The respective
interiors of the first and second intermediate header sections 9
and 11 of the second header tank 3 are connected together via a
communication member 12 which extends across and is joined to the
right ends of the intermediate header sections 9 and 11 and which
has a flow passage formed therein.
[0070] As shown in FIGS. 1 and 2, in the heat exchange core section
4, a plurality of flat refrigerant flow tubes 13 which extend in
the vertical direction, whose width direction coincides with the
air-passing direction (the front-rear direction), and which are
formed of aluminum extrudate are disposed in parallel such that
they are spaced from each other in the left-right direction. That
is, a plurality of pairs 14 each composed of a plurality of (in the
present embodiment, two) refrigerant flow tubes 13 spaced from one
another in the front-rear direction are disposed at predetermined
intervals in the left-right direction. An air-passing clearance 15
is formed between adjacent two of the pairs 14 each composed of the
front and rear refrigerant flow tube 13. An upper end portion of
each front refrigerant flow tube 13 is connected to the refrigerant
inlet header section 5, and a lower end portion of each front
refrigerant flow tube 13 is connected to the first intermediate
header section 9. Similarly, an upper end portion of each rear
refrigerant flow tube 13 is connected to the refrigerant outlet
header section 6, and a lower end portion of each rear refrigerant
flow tube 13 is connected to the second intermediate header section
11.
[0071] Each refrigerant flow tube 13 includes a plurality of
refrigerant flow channels 33 which are arranged in the width
direction of the refrigerant flow tube 13 (the front-rear
direction), and are separated from one another by partitions 34.
When the thickness of each partition 34 is represented by t (mm),
the height of each partition 34 is represented by h (mm), and a
tube height, which is the dimension of each refrigerant flow tube
13 in the thickness direction thereof, is represented by H (mm),
preferably, a relation 0.1.ltoreq.t.ltoreq.0.4 and a relation
0.64.ltoreq.h/H.ltoreq.0.86 are satisfied. Furthermore, when the
number of the partitions 34 of each refrigerant flow tube 13 is
represented by n and the width of each refrigerant flow tube 13 is
represented W (mm), preferably, a relation
0.07.ltoreq.(n.times.t)/W.ltoreq.0.31 is satisfied. Notably,
preferably, the tube height H of each refrigerant flow tube 13 is
12 to 25 mm, and the width W of each refrigerant flow tube 13 is
1.3 to 3.0 mm.
[0072] A cool storage material container 16 formed of aluminum
filled with a cool storage material (not shown) is disposed in each
of air-passing clearances 15 selected from all the air-passing
clearances 15, the selected passing clearances 15 being not
adjacent from one another, such that the cool storage material
container 16 extends over the front and rear refrigerant flow tubes
13 of the corresponding pairs 14. Also, a corrugated outer fin 17,
which is formed from an aluminum brazing sheet having a brazing
material layer on each of opposite surfaces thereof, is disposed in
each of the remaining air-passing clearances 15 such that the
corrugated outer fin 17 extends over the front and rear refrigerant
flow tubes 13 of the corresponding pairs 14. The corrugated outer
fin 17 disposed in each air-passing clearance 15 is brazed to the
front and rear refrigerant flow tubes 13 of the left-side and
right-side pairs 14 which define the air-passing clearance 15. That
is, the outer fin 17 is disposed in each of the air-passing
clearances 15 located on both sides of the air-passing clearance 15
in which the cool storage material container 16 is disposed. Also,
the outer fin 17, which is formed from an aluminum brazing sheet
having a brazing material layer on each of opposite surfaces
thereof, is disposed on the outer side of the pair 14 of the
refrigerant flow tubes 13 located at the left end, and is disposed
on the outer side of the pair 14 of the refrigerant flow tubes 13
located at the right end. These outer fins 17 are brazed to the
corresponding front and rear refrigerant flow tubes 13.
Furthermore, a side plate 18 formed of aluminum is disposed on the
outer side of each of the outer fins 17 located at the left and
right ends, respectively, and is brazed to the corresponding outer
fin 17.
[0073] As shown in FIGS. 2 and 3, each cool storage material
container 16 includes a container main body portion 21 and an
outward extending portion 22. The container main body portion 21 is
located rearward of the front edges of the front refrigerant flow
tubes 13, and is brazed to the front and rear refrigerant flow
tubes 13 of the corresponding pairs 14. The outward extending
portion 22 extends frontward from the front edge of the container
body portion 21, and projects frontward (downstream) in relation to
the front edges of the front rear refrigerant flow tubes 13. The
container body portion 21 of the cool storage material container 16
has a constant dimension in the thickness direction (the left-right
direction) over the entirety thereof. The outward extending portion
22 of the cool storage material container 16 has a dimension in the
vertical direction equal to that of the container body portion 21,
has a dimension in the left-right direction greater than that of
the container body portion 21, and bulges in relation to the
container body portion 21 to the outer side with respect to the
left-right direction (the outer side with respect to the direction
along which the refrigerant flow tubes 13 are arranged). The
dimension of the outward extending portion 22 in the left-right
direction is equal to a value obtained by adding the dimension of
the container body portion 21 of the cool storage material
container 16 in the left-right direction to a tube height, which is
the dimension of each refrigerant flow tube 13 in the thickness
direction (the left-right direction). For example, a paraffin-based
latent heat storage material having an adjusted freezing point of
about 5 to 10.degree. C. is used as a cool storage material charged
into the cool storage material container 16. Specifically,
pentadecane, tetradecane, or the like is used. The quantity of the
cool storage material charged into the cool storage material
container 16 is desirably determined such that the cool storage
material fills the interior of the cool storage material container
16 to a point near the upper end thereof. For example, a cool
storage material charging ratio, which is the ratio of the volume
of the charged cool storage material to the internal volume of the
cool storage material container 16, is preferably 70 to 90%, more
preferably, 70 to 80%. Notably, the cool storage material charging
ratio is that at room temperature.
[0074] The reason why it is preferred that the cool storage
material charging ratio, which is the ratio of the volume of the
charged cool storage material to the internal volume of one sealed
internal space 16a of the cool storage material container 16, is
set to 70 to 90% is that results as shown in FIGS. 4 and 5 were
obtained through computer simulation calculation.
[0075] Computer simulation calculation, the results of which are
shown in FIG. 4, was performed for the case where pentadecane was
used as a cool storage material, and the ambient temperature at the
time of charging (at the beginning) was 20.degree. C. The
calculation was performed, while the charging ratio of the cool
storage material charged into the cool storage material container
16 and the temperature of the atmosphere in which the cool storage
material container was disposed were changed.
[0076] Computer simulation calculation, the results of which are
shown in FIG. 5, was performed for the case where pentadecane was
used as a cool storage material, under the conditions that the
temperature of air flowing into the evaporator (1) with a cool
storage function was 25.degree. C., the relative humidity (RH) of
the air was 50%, and the quantity of air as measured on the
upstream side of the evaporator 1 with a cool storage function was
200 m.sup.3/h. The calculation was performed, while the charging
ratio of the cool storage material charged into the cool storage
material container 16 was changed.
[0077] The horizontal axis of the graph shown in FIG. 4 shows the
temperature of the atmosphere in which the cool storage material
container 16 was disposed (ambient temperature), and the vertical
axis thereof represents the internal pressure of the cool storage
material container 16. The horizontal axis of the graph shown in
FIG. 5 shows a cool storage time required to store a required
quantity of cool in the cool storage material within the cool
storage material container 16, and the vertical axis thereof
represents a cool release time over which a required quantity of
cool is released from the cool storage material within the cool
storage material container 16.
[0078] The graph shown in FIG. 4 reveals that, only in the case
where the charging ratio of the cool storage material charged into
the cool storage material container 16 is equal to or less than
90%, a sharp increase in the internal pressure can be prevented
even at an ambient temperature higher than 90.degree. C., which is
the upper limit of an ordinary temperature range of for use of a
car air conditioner including the evaporator 1 with a cool storage
function. Also, the graph shown in FIG. 5 reveals that, only in the
case where the charging ratio of the cool storage material charged
into the cool storage material container 16 is equal to or greater
than 70%, a required cool release time (T) can be attained by a
relatively short cool storage time.
[0079] The cool storage material container 16 is composed of two
generally rectangular aluminum plates 24 and 25, each of which is
formed, through press work, from an aluminum brazing sheet having a
brazing material layer on each of opposite sides thereof, and whose
peripheral edge portions are brazed together. A first bulging
portion 26 bulging rightward is provided over a portion of the
right-hand-side aluminum plate 24, which constitutes the cool
storage material container 16, the portion forming the container
body portion 21; i.e., the greater portion of the right-hand-side
aluminum plate 24 excluding a front portion thereof. Similarly, a
second bulging portion 27 is provided over a portion of the
right-hand-side aluminum plate 24 forming the outward extending
portion 22; i.e., the front portion of the right-hand-side aluminum
plate 24, such that the second bulging portion 27 extends over the
entire length in the vertical direction. The second bulging portion
27 extends frontward from the first bulging portion 26, bulges
rightward, and has a bulging height greater than that of the first
bulging portion 26. Furthermore, grooves 28 are formed, in a
grid-like pattern, on an outer surface of the portion of the
right-hand-side aluminum plate 24 forming the container body
portion 21, in regions to which the refrigerant flow tubes 13 are
brazed. The left-hand-side aluminum plate 25, which constitutes the
cool storage material container 16, has a shape which is a mirror
image of the shape of the right-hand-side aluminum plate 24, and
the same portions are denoted by the same reference numerals.
[0080] The two aluminum plates 24 and 25 are assembled and brazed
together such that openings of the first and second bulging
portions 26 and 27 face each other, whereby the cool storage
material container 16 is formed. The first bulging portions 26 of
the two aluminum plates 24 and 25 form the container body portion
21, and the second bulging portions 27 of the two aluminum plates
24 and 25 form the outward extending portion 22.
[0081] An inner fin 29 made of aluminum and extending from the rear
end of the container body portion 21 to the front end of the
outward extending portion 22 is disposed in the cool storage
material container 16 such that the inner fin 29 extends over
substantially the entirety of the cool storage material container
16 in the vertical direction. The inner fin 29 assumes a corrugated
shape, and has crest portions extending in the front-rear
direction, trough portions extending in the front-rear direction,
and connection portions connecting the crest portions and the
trough portions. The inner fin 29 has a constant fin height over
the entirety thereof, and is brazed to the inner surfaces of left
and right walls of the container body portion 21 of the cool
storage material container 16.
[0082] Each of the outer fins 17 assumes a corrugated shape, and
has crest portions extending in the front-rear direction, trough
portions extending in the front-rear direction, and connection
portions connecting the crest portions and the trough portions.
Each of the outer fins 17 has a fin body portion 31 and an outward
extending portion 32. The fin body portion 31 is located rearward
of the front edges of the front refrigerant flow tubes 13, and is
brazed to the front and rear refrigerant flow tubes 13 of the
corresponding pairs 14. The outward extending portion 32 extends
from the front edge of the fin body portion 31, and projects
frontward in relation to the front edges of the front refrigerant
flow tubes 13 (outward in the air-passing direction). The outward
extending portions 32 of the outer fins 17 disposed in two
air-passing clearances 15 located adjacent to and on opposite sides
of each air-passing clearance 15 in which the cool storage material
container 16 is disposed are brazed to the left and right side
surfaces of the outward extending portion 22 of the cool storage
material container 16. Furthermore, a spacer 35 made of aluminum is
disposed between the outward extending portions 32 of adjacent ones
of the outer fins 17, and is brazed to the outward extending
portions 32.
[0083] The above-described evaporator 1 with a cool storage
function constitutes a refrigeration cycle in combination with a
compressor driven by an engine of a vehicle, a condenser
(refrigerant cooler) for cooling the refrigerant discharged from
the compressor, and an expansion valve (pressure-reducing unit) for
reducing the pressure of the refrigerant having passed through the
condenser. The refrigeration cycle is installed, as a car air
conditioner, in a vehicle, such as an automobile, which temporarily
stops the engine, which serves as a drive source of the compressor,
when the vehicle is stopped. In the case of such a car air
conditioner, when the compressor is operating, low pressure,
two-phase refrigerant (a mixture of vapor refrigerant and liquid
refrigerant) having been compressed by the compressor and having
passed through the condenser and the expansion valve passes through
the refrigerant inlet 7, and enters the inlet header section 5 of
the evaporator 1. The refrigerant then passes through all the front
refrigerant flow tubes 13, and enters the first intermediate header
section 9. The refrigerant having entered the first intermediate
header section 9 passes through the communication member 12, and
enters the second intermediate header section 11. After that, the
refrigerant passes through all the rear refrigerant flow tubes 13,
enters the outlet header section 6, and flows out via the
refrigerant outlet 8. When the refrigerant flows through the
refrigerant flow tubes 13, the refrigerant performs heat exchange
with air passing through the air-passing clearances 15, and flows
out of the refrigerant flow tubes 13 in a vapor phase.
[0084] At that time, the cool storage material within the container
body portion 21 of each cool storage material container 16 is
cooled by the refrigerant flowing through the refrigerant flow
tubes 13, and the cool stored in the cooled cool storage material
within the container body portion 21 is transferred to the cool
storage material within the outward extending portion 22 of the
cool storage material container 16 via the inner fin 29.
Furthermore, the cool storage material within the outward extending
portion 22 of the cool storage material container 16 is cooled by
air having been cooled by the refrigerant while passing through the
air-passing clearances 15. As a result, cool is stored in the
entire cool storage material within the cool storage material
container 16.
[0085] When the compressor stops, the cool stored in the cool
storage material within the container body portion 21 and outward
extending portion 22 of each cool storage material container 16 is
transferred to the left and right walls of the container body
portion 21 and outward extending portion 22 via the inner fine 29.
The cool transferred to the left and right walls of the container
body portion 21 is transferred to air passing through the
corresponding air-passing clearances 15 via the corresponding
refrigerant flow tubes 13 and the fin body portions 31 of the outer
fins 17 brazed to the refrigerant flow tubes 13. The cool
transferred to the left and right walls of the outward extending
portion 22 is transferred to air passing through the corresponding
air-passing clearance 15 via the outward extending portions 32 of
the outer fins 17 brazed to the left and right side surfaces of the
outward extending portion 22. Accordingly, even when the
temperature of air having passed through the evaporator 1
increases, the air is cooled, so that a sharp drop in the cooling
capacity can be prevented.
[0086] As described above, when the thickness of the partitions 34
of the refrigerant flow tubes 13 is represented by t (mm),
satisfaction of the relation 0.1.ltoreq.t.ltoreq.0.4 is preferred,
because the results as shown in FIGS. 6 and 7 were obtained through
computer simulation calculation. This computer simulation
calculation was performed, while the thickness t of the partitions
34 was changed under the conditions that the width W of the
refrigerant flow tubes 13 was 16.95 mm, the tube height H thereof
was 1.4 mm, and the number n of the partitions 34 was 13.
[0087] The left side vertical axis of the graph shown in FIG. 6
represents the average temperature of air having passed through the
heat exchange core section 4 during a cool release period in which
the compressor stops, and cool is released from the cool storage
material within the cool storage material container 16. The left
side vertical axis of the graph shown in FIG. 7 represents the
quantity of moving cool which is transferred to each cool storage
material container 16, via the corresponding refrigerant flow tubes
13, from the outer fins 17 disposed in the air-passing clearances
15 adjacent to the air-passing clearance 15 in which the cool
storage material container 16 is disposed, during a cool storage
period in which the compressor operates, and cool is stored in the
cool storage material within the cool storage material container
16. The right side vertical axes of the graphs shown in FIGS. 6 and
7 each represent the quantity of moving cool transferred from each
cool storage material container 16, via the corresponding
refrigerant flow tubes 13, to the outer fins 17 disposed in the
air-passing clearances 15 adjacent to the air-passing clearance 15
in which the cool storage material container 16 is disposed, during
a cool release period in which the compressor stops, and cool is
released from the cool storage material within the cool storage
material container 16. The graph shown in FIG. 6 reveals that, when
the thickness of the partitions 34 is 0.1 to 0.4 mm, the average
temperature of air having passed through the heat change core
section 4 at the time of cool release decreases efficiently. When
the thickness of the partitions 34 exceeds 0.4 mm, the degree of
drop of the average temperature decreases. Also, the graph shown in
FIG. 7 reveals that, when the thickness of the partitions 34 is 0.1
to 0.4 mm, excellent cool storage performance and excellent cool
release performance are attained. That is, during a cool storage
period, a large quantity of cool is transferred to each cool
storage material container 16, via the corresponding refrigerant
flow tubes 13, from the outer fins 17 disposed in the air-passing
clearances 15 adjacent to the air-passing clearance 15 in which the
cool storage material container 16 is disposed, whereby excellent
cool storage performance is attained; and during a cool storage
period, a large quantity of cool is transferred from each cool
storage material container 16, via the corresponding refrigerant
flow tubes 13, to the outer fins 17 disposed in the air-passing
clearances 15 adjacent to the air-passing clearance 15 in which the
cool storage material container 16 is disposed, whereby excellent
cool release performance is attained. Notably, the reason why the
lower limit of the thickness t of the partitions 34 is set to 0.1
mm is that, when the thickness of the partitions 34 is less than
0.1 mm, manufacture becomes difficult.
[0088] Also, when the tube height, which is the dimension of the
refrigerant flow tubes 13 in the thickness direction, is
represented by H (mm) and the height of the partitions is
represented by h (mm), satisfaction of the relation
0.64.ltoreq.h/H.ltoreq.0.86 is preferred, because the results as
shown in FIGS. 8 and 9 were obtained through computer simulation
calculation. This computer simulation calculation was performed,
while the ratio of the height h of the partitions 34 to the tube
height H was changed, under the conditions that the width W of the
refrigerant flow tubes 13 was 16.95 mm, the tube height H thereof
was 1.4 mm, the number n of the partitions 34 was 13, and the
thickness t of the partitions 34 was 0.2 mm.
[0089] The left side vertical axis of the graph shown in FIG. 8
represents the average temperature of air having passed through the
heat exchange core section 4 during a cool release period in which
the compressor stops, and cool is released from the cool storage
material within the cool storage material container 16. The left
side vertical axis of the graph shown in FIG. 9 represents the
quantity of moving cool which is transferred to each cool storage
material container 16, via the corresponding refrigerant flow tubes
13, from the outer fins 17 disposed in the air-passing clearances
15 adjacent to the air-passing clearance 15 in which the cool
storage material container 16 is disposed, during a cool storage
period in which the compressor operates, and cool is stored in the
cool storage material within the cool storage material container
16. The right side vertical axes of the graphs shown in FIGS. 8 and
9 each represent the quantity of moving cool transferred from each
cool storage material container 16, via the corresponding
refrigerant flow tubes 13, to the outer fins 17 disposed in the
air-passing clearances 15 adjacent to the air-passing clearance 15
in which the cool storage material container 16 is disposed, during
a cool release period in which the compressor stops, and cool is
released from the cool storage material within the cool storage
material container 16. The graph shown in FIG. 8 reveals that, when
the ratio h/H is 0.64 to 0.86, the average temperature of air
having passed through the heat change core section 4 at the time of
cool release decreases efficiently. When the ratio is less than
0.64, the degree of drop of the average temperature decreases.
Also, the graph shown in FIG. 9 reveals that, when the ratio h/H is
0.64 to 0.86, excellent cool storage performance and excellent cool
release performance are attained. That is, during a cool storage
period, a large quantity of cool is transferred to each cool
storage material container 16, via the corresponding refrigerant
flow tubes 13, from the outer fins 17 disposed in the air-passing
clearances 15 adjacent to the air-passing clearance 15 in which the
cool storage material container 16 is disposed, whereby excellent
cool storage performance is attained; and during a cool storage
period, a large quantity of cool is transferred from each cool
storage material container 16, via the corresponding refrigerant
flow tubes 13, to the outer fins 17 disposed in the air-passing
clearances 15 adjacent to the air-passing clearance 15 in which the
cool storage material container 16 is disposed, whereby excellent
cool release performance is attained. Notably, the reason why the
upper limit of the ratio h/H is set to 0.86 is that, when the ratio
h/H exceeds the limit, manufacture becomes difficult.
[0090] The above-described embodiment may be modified such that, as
in the case of a so-called laminate-type evaporator, the
refrigerant flow tubes of the evaporator with a cool storage
function are provided in flat hollow bodies each formed of two
aluminum plates which face each other and whose peripheral edge
portions are brazed together. That is, each of the refrigerant flow
tubes may be one formed between the two aluminum plates which
constitute the flat hollow body and having a bulged shape.
[0091] The above-described evaporator 1 with a cool storage
function may be disposed in an inclined posture such that the upper
ends of the refrigerant flow tubes 13 and the cool storage material
containers 16 of the heat exchange core section 4 are located on
the upstream side or the downstream side (for example, upstream
side) in relation to the lower ends thereof. In this case,
preferably, the height of the liquid level of the cool storage
material within the inclined cool storage material container 16 is
equal to or higher than 90% the vertical height of a edge portion
of the cool storage material container 16 located on the side
toward the inclination direction, and desirably, the height of the
liquid level of the cool storage material within the inclined cool
storage material container 16 is equal to the vertical height of
the edge portion of the cool storage material container 16 located
on the side toward the inclination direction.
[0092] FIGS. 10 to 12 show modifications of the cool storage
material container.
[0093] In the case of a cool storage material container 40 shown in
FIG. 10, an outward extending portion 41, which extends from the
front edge of the container body portion 21 and projects frontward
(downstream) in relation to the front edges of the front
refrigerant flow tubes 13, is composed of a base portion 42 and a
plurality of projection portions 43. The dimensions of the base
portion 42 in the vertical and left-right directions are equal to
those of the container body portion 21. The projection portions 43
are provided on the base portion 42 such that the projection
portions 43 are spaced from one another in the vertical direction,
and are bulged outward from the base portion 42 in the left-right
direction. The projection portions 43 assume an oblong shape, and
are inclined downward toward the front side, as viewed from the
outer side with respect to the left-right direction. The dimension
of the projection portions 43 of the outward extending portion 41
in the left-right direction is equal to a value obtained by adding
the dimension of the container body portion 21 of the cool storage
material container 40 in the left-right direction to the tube
height, which is the dimension of each refrigerant flow tube 13 in
the left-right direction.
[0094] The outward extending portion 32 of the corresponding outer
fin 17 is brazed to projecting end surfaces of the projection
portions 43 of the outward extending portion 41.
[0095] The first bulging portion 26 bulging rightward is provided
over a portion of the right-hand-side aluminum plate 24, which
constitutes the cool storage material container 40, the portion
forming the container body portion 21; i.e., the greater portion of
the right-hand-side aluminum plate 24 excluding a front portion
thereof. Also, a second bulging portion 44 is provided over a
portion of the right-hand-side aluminum plate 24 forming the
outward extending portion 41; i.e., the front portion of the
right-hand-side aluminum plate 24, such that the second bulging
portion 44 extends over the entire length in the vertical
direction. The second bulging portion 44 extends frontward from the
first bulging portion 26, bulges rightward, and has a bulging
height equal to that of the first bulging portion 26. Furthermore,
by means of deforming the bulging top wall of the second bulging
portion 44, a plurality of third bulging portions 45 bulging
rightward in relation to the second bulging portion 44 are provided
on the bulging top wall of the second bulging portion 44 such that
they are spaced from one another in the vertical direction. The
left-hand-side aluminum plate 25, which constitutes the cool
storage material container 40, has a shape which is a mirror image
of the shape of the right-hand-side aluminum plate 24, and the same
portions are denoted by the same reference numerals.
[0096] The structure of the remaining portion is identical with
that of the cool storage material container 16 of the
above-described embodiment.
[0097] In the case of a cool storage material container 50 shown in
FIG. 11, a staggered inner fin 51 made of aluminum and extending
from the rear end of the container body portion 21 to the front end
of the outward extending portion 22 is disposed in the cool storage
material container 50 such that the inner fin 51 extends over
substantially the entirety thereof in the vertical direction. The
inner fin 51 is composed of a plurality of corrugated strips 52,
each of which has crest portions 52a extending in the front-rear
direction (air-passing direction), trough portions 52b extending in
the front-rear direction, and connection portions 52c connecting
the crest portion 52a and the trough portion 52b. The corrugated
strips 52 are arranged in the air-passing direction and integrally
connected with one another such that the crest portions 52a and the
trough portions 52b of one of two strips 52 adjacent to each other
in the front-rear direction are positionally shifted in the
vertical direction from those of the other strip 52.
[0098] The structure of the remaining portion is identical with
that of the cool storage material container 16 of the
above-described embodiment.
[0099] In the case of a cool storage material container 60 shown in
FIG. 12, through inward deformation of the left and right side
walls of the cool storage material container 60, an internal-volume
reducing portion 61 for reducing the internal volume of the cool
storage material container 60 is formed at a lower portion of the
container body portion 21, the lower portion being located upstream
of the center of the clearance between the front and rear
refrigerant flow tubes 13. The dimension of the internal-volume
reducing portion 61 in the left-right direction is smaller than the
dimension of the container body portion 21 in the left-right
direction. Thus, the internal volume of the cool storage material
container 60 decreases, as compared with the case where the
internal-volume reducing portion 61 is not provided. The amount by
which the internal volume of the cool storage material container 60
is reduced by the internal-volume reducing portion 61 is determined
such that the cool storage material exists in the vicinity of the
upper end of the cool storage material container 60, even when the
cool storage material charging ratio (the ratio of the volume of
the charged cool storage material to the internal volume of the
sealed internal space of the cool storage material container 60)
for an assumed case where the internal-volume reducing portion 61
is not provided (that is, the thickness of the container body
portion 21 in the left-right direction is constant over the
entirety thereof) is 70 to 90%, preferably, 70 to 80%.
[0100] The internal-volume reducing portion 61 is provided by means
of forming a recess portion 62, which is formed through inward
deformation of the bulging top wall 26a of the first bulging
portion 26 of each of the two aluminum plates 24 and 25
constituting the cool storage material container 60.
[0101] Furthermore, at a location where the internal-volume
reducing portion 61 is provided, the inner fin 29 deforms in a
buckled shape, so that the strength of the cool storage material
container 60 decreases at a location thereof where the
internal-volume reducing portion 61 is provided. However, the cool
storage material container 60 is designed to have a sufficient
strength such that, within an ordinary temperature range (e.g., -40
to 90.degree. C.) of use environment, the cool storage material
container 60 does not break even when the internal pressure
increases because of a change in the density of the cool storage
material in the liquid phase and thermal expansion of air remaining
in the cool storage material container 60.
[0102] In the case of the cool storage material container 60, a
portion of the container body portion 21 located frontward of the
internal-volume reducing portion 61 and being in contact with the
front refrigerant flow tubes 13 are brazed to the refrigerant flow
tubes 13 over the entire height.
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