U.S. patent application number 11/440153 was filed with the patent office on 2006-11-30 for heat exchanger for dryer and condensing type dryer using the same.
This patent application is currently assigned to LG Electronics Inc.. Invention is credited to Yoon-Seob Eom, Hyun-Uk Lee, Jung-Geun Oh.
Application Number | 20060266506 11/440153 |
Document ID | / |
Family ID | 36919529 |
Filed Date | 2006-11-30 |
United States Patent
Application |
20060266506 |
Kind Code |
A1 |
Lee; Hyun-Uk ; et
al. |
November 30, 2006 |
Heat exchanger for dryer and condensing type dryer using the
same
Abstract
A heat exchanger for a dryer includes a core in which a
plurality of tube units and a plurality of fin units are
alternately stacked. Front and rear covers are attached at front
and rear sides of the core. A front plate is positioned between the
core and the front cover and a rear plate is positioned between the
core and the rear cover. The plates have openings at locations
corresponding to the opened ends of the tube units. The plates are
physically coupled with the front and rear covers. The plates are
also attached to the core with a cladding material by a brazing
operation.
Inventors: |
Lee; Hyun-Uk;
(Gyeongsangnam-Do, KR) ; Oh; Jung-Geun;
(Gyeongsangnam-Do, KR) ; Eom; Yoon-Seob;
(Gyeongsangnam-Do, KR) |
Correspondence
Address: |
FLESHNER & KIM, LLP
P.O. BOX 221200
CHANTILLY
VA
20153
US
|
Assignee: |
LG Electronics Inc.
|
Family ID: |
36919529 |
Appl. No.: |
11/440153 |
Filed: |
May 25, 2006 |
Current U.S.
Class: |
165/166 |
Current CPC
Class: |
F28F 9/0219 20130101;
F28D 7/1684 20130101; D06F 58/24 20130101 |
Class at
Publication: |
165/166 |
International
Class: |
F28F 3/00 20060101
F28F003/00 |
Foreign Application Data
Date |
Code |
Application Number |
May 27, 2005 |
KR |
10-2005-45238 |
Jun 13, 2005 |
KR |
10-2005-50558 |
Jun 22, 2005 |
KR |
10-2005-54141 |
Claims
1. A heat exchanger, comprising: a core comprising a plurality of
tube units configured to conduct a flow of moist heated air and a
plurality of fin units configured to conduct a flow of ambient air,
wherein the plurality of tube units and plurality of fin units are
stacked together in an alternating fashion to form the core; a
front cover coupled to a front of the core and configured to
conduct a flow of air into the plurality of tube units; a rear
cover coupled to a rear of the core and configured to conduct a
flow of air out of the plurality of tube units; and at least one
plate positioned between the core and one of the front cover and
the rear cover, wherein a plurality of openings are formed in the
plate at locations that correspond to open ends of the plurality of
tube units.
2. The heat exchanger of claim 1, wherein the at least one plate is
bonded to the core by a cladding material.
3. The heat exchanger of claim 2, wherein the cladding material
melts at a temperature that is lower than melting points of the
tube units, the fin units and the at least one plate.
4. The heat exchanger of claim 2, wherein the cladding material
comprises a metal having good heat conductivity.
5. The heat exchanger of claim 1, wherein the at least one plate
includes serrated tabs on its exterior periphery which are
configured to be bent to attach the at least one plate to one of
the front cover and the rear cover.
6. The heat exchanger of claim 1, wherein the at least one plate
comprises: a front plate coupled to the front of the core and to
the front cover; and a rear plate coupled to the rear of the core
and to the rear cover.
7. The heat exchanger of claim 6, wherein the front and rear plates
are coupled to the core by a cladding material, and wherein the
front and rear plates are coupled to the front and rear covers,
respectively, by mechanical attachment means.
8. A dryer comprising the heat exchanger of claim 1.
9. A heat exchanger, comprising: a core comprising a plurality of
tube units configured to conduct a flow of moist heated air and a
plurality of fin units configured to conduct a flow of ambient air,
wherein the plurality of tube units and plurality of fin units are
stacked together in an alternating fashion to form the core; a
front cover coupled to a front of the core and configured to
conduct a flow of air into the plurality of tube units, wherein a
protrusion is formed on a side of the front cover adjacent the
core; a front cover plate positioned between the core and the front
cover and mechanically attached to the protrusion on the front
cover; a rear cover coupled to a rear of the core and configured to
conduct a flow of air out of the plurality of tube units, wherein a
protrusion is formed on a side of the rear cover adjacent the core;
and a rear cover plate positioned between the core and the rear
cover and mechanically attached to the protrusion on the rear
cover.
10. The heat exchanger of claim 9, wherein the front cover plate
and the rear cover plate are both attached to the core by a
cladding material.
11. The heat exchanger of claim 10, wherein the cladding material
has a melting point that is lower than melting points of the core,
the front cover plate and the rear cover plate.
12. The heat exchanger of claim 11, wherein the cladding material
comprises a metal and has excellent heat conducting properties.
13. The heat exchanger of claim 9, wherein a plurality serrated
tabs are formed on an exterior periphery of the front cover plate
and the rear cover plate, and wherein the serrated tabs are bent
around the protrusions on the front cover and rear cover to attach
the front cover plate to the front cover and to attach the rear
cover plate to the rear cover.
14. The heat exchanger of claim 13, wherein the protrusions on the
front cover and rear cover extend substantially around the
periphery of the front cover and rear cover.
15. The heat exchanger of claim 9, wherein the core, the front
cover plate and the rear cover plate are all made of metal having
excellent heat conducting properties.
16. The heat exchanger of claim 9, wherein the front cover plate
and the rear cover plate both have a plurality of openings that
correspond to opened ends of the plurality of tube units.
17. A dryer comprising the heat exchanger of claim 9.
18. A heat exchanger, comprising: a core comprising a plurality of
tube units configured to conduct a flow of moist heated air and a
plurality of fin units configured to conduct a flow of ambient air,
wherein the plurality of tube units and plurality of fin units are
stacked together in an alternating fashion to form the core; a
front cover coupled to a front of the core and configured to
conduct a flow of air into the plurality of tube units; a front
cover plate positioned between the core and the front cover; a
front sealing member positioned between the front cover and the
front cover plate, wherein the front sealing member is configured
to prevent condensate from the tube units from entering the fin
units; a rear cover coupled to the rear of the core and configured
to conduct a flow of air out of the plurality of tube units; a rear
cover plate positioned between the core and the rear cover; and a
rear sealing member positioned between the rear cover and the rear
cover plate, wherein the rear sealing member is configured to
prevent condensate from the tube units from entering the fin
units.
19. The heat exchanger of claim 18, wherein at least one of the
front cover plate and the rear cover plate have a plurality of
apertures at locations that correspond to opened ends of the
plurality of tube units.
20. The heat exchanger of claim 18, wherein the front cover plate
and the rear cover plate are coupled to the core by a cladding
material.
21. The heat exchanger of claim 20, wherein the front cover plate
and the rear cover plate are mechanically attached, respectively,
to the front and rear covers.
22. The heat exchanger of claim 21, wherein tabs are formed on the
exterior periphery of the front and rear cover plates, and wherein
the tabs are bent to attach the front and rear cover plates to the
front and rear covers, respectively.
23. The heat exchanger of claim 18, wherein the front and rear
sealing members are formed of polyurethane.
24. The heat exchanger of claim 18, wherein the front and rear
sealing members are formed of a material that is capable of
withstanding temperatures above 80.degree. C.
25. A dryer comprising the heat exchanger of claim 18.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a heat exchanger for a
dryer and, more particularly, to a heat exchanger with a new
structure capable of improving heat transfer efficiency.
[0003] 2. Description of the Related Art
[0004] In general, a dryer performs a drying operation on clothing
by blowing hot air generated by a heater into a drum. Dryers can be
divided into exhaust type dryers and condensing type dryers,
depending on a method for processing the humid air generated by the
drying operation.
[0005] In case of the exhaust type dryer, humid air exhausted from
a drum is discharged to outside of the dryer. In the condensing
type dryer, humid air discharged from the drum is condensed to
remove moisture, and the moisture-removed dried air is transferred
back into the drum so as to be re-circulated.
[0006] The condensing type dryer includes a drum for drying
laundry, a filter for filtering out foreign materials, a heat
exchanger (or condenser) for removing moisture of the laundry
through a heat exchange operation, a fan for facilitating drying by
generating air flow, a heater for heating the air flow to shorten
the drying time, and piping for connecting the components.
[0007] FIGS. 1a and 1b show an example of a condensing type dryer.
As shown in FIGS. 1a and 1b, an arrow I indicates a flow of
external air and an arrow II indicates a flow of air that is
re-circulated through the drum of the dryer. As shown, a drum 11 in
which laundry is to be received is rotatably installed inside a
main body 10, and a door 12 is installed at a front side of the
main body 10. The drum 11 is rotated by a belt 19 connected to a
motor 17 installed at a lower portion of the main body 10.
[0008] A heat exchanger (or condenser) 13 is installed at the lower
portion of the main body 10 and condenses hot and humid air
circulated through the drum 11 to remove moisture from the air.
Front and rear sides of the heat exchanger 13 are connected with a
circulation duct 14. The circulation duct 14 is connected with both
front and rear sides of the drum 11, so that when air is discharged
through the drum 11, it can be re-introduced into the drum 11 after
passing through the heat exchanger 13.
[0009] A heater 15 for heating air which has passed through the
heat exchanger 13 and a circulation fan 16 for forcibly circulating
air through a circulation duct 14 are installed at the circulation
duct 14. The circulation fan 16 is connected with a different shaft
of the motor 17 for driving the drum 11.
[0010] In order to condense air circulated through the circulation
duct 14, external cold air must be supplied to the heat exchanger
13. For this purpose, an external air supply duct 18 connected with
an outer side of the main body 10 is connected with one side of the
heat exchanger 13. A cooling fan 20 for forcibly sucking external
air through the external air supply duct 18 and discharging it into
the main body 10 and a cooling fan driving motor 21 are installed
at the opposite side of the heat exchanger 13 to which the external
air supply duct 18 connected.
[0011] Reference numeral 22 is a filter for filtering out foreign
materials such as waste thread or the like from the air exhausted
to the circulation duct 14 through the front side of the drum 11. A
water receiver (not shown) for collecting condensed water generated
during a condensing process is installed at a lower side of the
heat exchanger 13. A pump 23 for sending the condensed water
collected in the water receiver to a storage tank 2 is also
installed at the lower side of the heat exchanger 13.
[0012] The purpose of the dryer is to dry laundry quickly with as
little power consumption as possible. In order to reduce power
consumption and shorten the laundry drying time, a method for
increasing a capacity of the heater or the fan has been considered.
However, doing so adds additional cost to the dryer and electrical
charges increase due to an increase in the power consumption. In
addition, noise can also increase.
[0013] FIG. 2 shows an example of a heat exchanger that can be used
in a condensing type clothes dryer. As shown, the heat exchange
includes an external air inflow unit 13a and a humid air inflow
unit 13b. Dry ambient air is introduced into the external air
inflow unit 13a and humid air that is circulated through the dyrer
is introduced through the humid air inflow unit 13b. The heat
exchanger allows heat from the humid air to be transferred to the
flow of external air. As a result, water droplets condense on the
inner surface of the heat exchanger. In the condensing type dryer,
the heat exchanger is a core component playing an important role in
the overall drying efficiency.
BRIEF DESCRIPTION OF THE INVENTION
[0014] One object of the present invention is to provide a heat
exchanger structure capable of increasing heat exchange
efficiency.
[0015] Another object of the present invention is to obtain
economical efficiency in the mass production of such devices and in
the materials used.
[0016] Still another object of the present invention is to enhance
drying efficiency by using a heat exchanger with better performance
in a dryer or a washing machine that includes a drying
function.
[0017] To achieve at least the above objects in whole or in part,
the present invention provides a heat exchanger for a dryer which
includes humid air flowing units having a duct form with both ends
opened. The heat exchanger also includes external air flowing
units, which are alternately stacked with the humid air flowing
units to form a core. Front and rear covers are attached at front
and rear sides of the core. Plates are positioned between the core
of the heat exchange unit and the front cover and between the core
and the rear cover. The plates have a plurality of openings
corresponding to the opened ends of the humid air flowing
units.
[0018] Preferably, the plates are bonded to the core of the heat
exchange unit by a cladding material. Also, preferably, serrated
extending tabs formed along peripheral edges of the plates are bent
around extending protrusions on the front and rear covers to
physically couple the plates with their respective covers.
[0019] The core of the heat exchange unit and the plates may be
made of a metal material with excellent heat conductivity, and the
cladding material may include a metal component having a melting
point lower than that of the plates and the core of the heat
exchange unit.
[0020] A condensing type dryer or a washing machine that includes a
drying function that embodies the invention includes: a drum
rotatably installed inside a cabinet; a heat exchanger for
condensing moisture from a flow of humid air; a fan for generating
a flow of air; and a heat source for applying heat to the
re-circulated air. In this dryer, the heat exchanger includes a
plurality of tube units which conduct a flow of humid air through
the heat exchanger, and a plurality of fin units that conduct a
flow of exterior air through the heat exchanger. The tube units and
fin units are alternately stacked to form a core of the heat
exchanger. Front and rear covers are attached at front and rear
sides of the heat exchange unit, the center thereof being opened.
Plates are positioned between the core of the heat exchange unit
and the front and rear covers. The plates have a plurality of
openings corresponding to opened ends of the tube units.
[0021] The heat exchanger according to the present invention has
advantages in that the bonding between the heat exchange unit and
the front and rear covers is strong, heat exchange performance is
excellent. Also, the technique used to bond the plates and attached
front and rear covers to the heat exchanger core takes considerably
less time than traditional methods that rely upon an epoxy,
resulting in more efficient mass production. As a result, a
fabrication cost of a dryer or a washing machine employing the heat
exchanger can be reduced.
[0022] Additional advantages, objects, and features of the
invention will be set forth in part in the description which
follows and in part will become apparent to those having ordinary
skill in the art upon examination of the following or may be
learned from practice of the invention. The objects and advantages
of the invention may be realized and attained as particularly
pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The invention will be described in detail with reference to
the following drawings in which like reference numerals refer to
like elements, and wherein:
[0024] FIG. 1a is a sectional view showing an example of a clothes
dryer;
[0025] FIG. 1b is a plan view of the clothes dryer in FIG. 1;
[0026] FIG. 2 is a perspective view showing an example of a heat
exchanger;
[0027] FIG. 3 is an exploded view showing components of a heat
exchanger according to the present invention;
[0028] FIG. 4 is a front view of a plate of the heat exchanger
according to the present invention;
[0029] FIG. 5a is a perspective view of a front cover of the heat
exchanger according to the present invention;
[0030] FIG. 5b is a side view of the front cover of the heat
exchanger according to the present invention;
[0031] FIG. 5c is a front view of a sealing member formed at a rear
side of the front cover of the heat exchanger according to the
present invention;
[0032] FIG. 6 is a front view of a different plate of the heat
exchanger according to the present invention;
[0033] FIG. 7 is a side view of the heat exchanger with a plate
coupled therewith;
[0034] FIG. 8 is a side view of a different sealing member of the
heat exchanger according to the present invention; and
[0035] FIG. 9 is a side view of the heat exchanger including the
sealing member in FIG. 8.
DETAILED DESCRIPTION OF THE INVENTION
[0036] The present invention will be described in detail with
reference to the accompanying drawings.
[0037] FIG. 3 shows components of a heat exchanger according to the
present invention. A heat exchange unit 30, in which heat is
exchanged between external air and internal air, includes a
plurality of tube units 32 and a plurality of fin units 34 that are
alternately stacked. Both ends of the tube units 32 are opened and
the tube units 32 have a duct structure which may have a
rectangular cross-sectional shape. Of course, other cross-sectional
shapes could also be used. A pipe (not shown) which re-circulates
air through the dryer is connected with both ends of the tube units
32. The fin units 34 include a plurality of air passages with heat
exchanging fins in the air passages. The fin units 34 can be formed
by repeatedly bending a thin metal plate in a zigzag fashion. The
tube units 32 and the fin units 34 are repeatedly stacked on one
another in an alternating fashion to form the core of the heat
exchanger. The tube units 32 and the fin units 34 can be made of a
metal material with excellent heat transfer characteristics, and
preferably are made of aluminum or an aluminum alloy.
[0038] Front and rear covers 40 and 42 are coupled with the front
and rear surfaces of the heat exchange unit 30. The front and rear
covers 40 and 42 perform a coupling medium function to allow the
heat exchange unit 30 to be easily coupled with the re-circulation
pipe or other components. The front and rear covers 40 and 42 may
be made of a plastic group such as ABS-GF and are formed typically
according to an injection molding method. A sealing member can be
additionally formed at the portion where the front and rear covers
40 and 42 are coupled at the sides of the heat exchange unit 30 in
order to prevent a leakage of air.
[0039] The front and rear covers 40 and 42 can be attached to the
heat exchange unit 30 through a mechanical method, but are usually
attached using an adhesive (bonding agent) as a coupling medium to
prevent a leakage of air or heat. For example, the front and rear
covers 40 and 42 can be attached using epoxy bonding. Where an
epoxy bonding agent is used, usually an organic bonding agent which
has weak heat transfer characteristics is used. In addition, the
organic bonding agents require a significant amount of time to
bond. As a result, the assembly time is long and productivity is
hurt. For example, some epoxy bonds take as long as two days to
fully cure.
[0040] In the present invention, a thin metal coupling plate,
instead of a bonding agent, is used to attach the front and rear
covers 40 and 42 to the core of the heat exchange unit 30. FIG. 4
shows the structure of one embodiment of a coupling plate according
to the present invention. As shown, the plate 50 is a thin metal
plate including a plurality of openings 52 therein. The openings 52
have a size and location that corresponds to the opened ends of the
tube units 32 of the heat exchange unit 30. As such, the openings
serve as a flow passage for humid air circulated through the tube
units 32. In addition, bars 51 located between the openings 52 of
the plate have a size and location corresponding to the fin units
34 of the heat exchange unit 30. Thus the bars 51 serve as one side
of an air passage through the fin units to prevent external air
passing through the fin units 34 from flowing out the sides of the
fin units 34.
[0041] The plate 50 is formed to have a size and shape that matches
the front and rear end portions of the heat exchange unit 30.
Preferably, the plate 50 is thin and made of light metal or a metal
alloy with excellent heat conductivity. If possible, the plate 50
is made of the same material as the core of the heat exchange unit
30.
[0042] Preferably, the plate 50 is attached to the core of the heat
exchange unit 30 without using an epoxy type bonding agent that
might degrade heat transfer. Instead, in the present invention, the
plated 50 and the core of the heat exchange unit 30 are attached to
each other through a brazing method. The brazing allows the two
metals to be firmly bonded within a very short time. In the present
invention, a metal cladding material is preferably used as a
brazing medium. The cladding material has a melting point lower
than the melting points of the materials of the core of the heat
exchange unit 30 and the plate 50. Also, the cladding material
layer is preferably very thin.
[0043] For example, when the material of the plate 50 and the core
of the heat exchange unit 30 is aluminum, a cladding material
having a melting point lower than the melting point of aluminum,
which is approximately 550.degree. C., is selectively used. But the
present invention is not limited thereto.
[0044] During the brazing process, a cladding material may be
coated onto the plate 50, to which the core of the heat exchange
unit 30 is attached. Preferably, the cladding material layer has a
thickness of about 100 micrometers or less. Then, the attached
plate 50 and heat exchange unit 30 are heated to a temperature
higher than the melting point of the cladding material, but lower
than 550.degree. C. (the melting point of aluminum). The cladding
material becomes molten, and when the assembly is cooled, the plate
50 and the heat exchange unit 30 are firmly bonded together.
Typically, there is little cladding material remaining after the
brazing process. Even if a very small amount of cladding material
remains at the bonding portion between the plate 50 and the heat
exchange unit 30, the metal component of the cladding material does
not interfere with heat transfer, so the heat exchanger is not
affected negatively.
[0045] FIGS. 5a and 5b show the structure of the front cover 40 (or
the rear cover 42) according to the present invention. As shown,
the front cover 40 has a cross-sectional similar to a rectangular
shape and includes an opening therein. The opening has almost the
same shape as the cross-sectional shape of the core of the heat
exchange unit and serves as a passage to allow internal circulated
humid air of the dryer to flow to other parts of the dryer after
passing through the tube units 32.
[0046] Preferably, the opening formed at the front portion 44a of
the front cover 40 does not have a channel corresponding to the
regions of the tube units 32. It is preferable to form the channel
regions using the plate, which also serves as a means of connecting
the front cover 40 and the heat exchange unit 30. As shown in FIG.
5a, a central support wall 45 may formed at the central opening of
the front cover 40, but it is not an essential element. That is,
the central support wall 45 can be omitted according to
circumstances.
[0047] Because the front cover 40 (or the rear cover) is coupled to
the heat exchange unit 30 via the plate 50, it is preferred that
the front cover (or the rear cover) has a coupling structure that
facilitates its coupling with the plate 50. In the present
invention, a rear protrusion 44b is integrally formed to extend
with a certain length at a rear side of the front cover 40. The
rear protrusion 44b is used to physically couple the cover 40 to
the plate 50. As shown in FIG. 5a, in order to facilitate physical
coupling, a rim 44c can be formed to be thicker at an edge of the
rear protrusion 44b. In addition, the rim 44c can be formed of a
sealing member. The sealing member 44c can be made of a material
with elasticity, and can be additionally (or integrally) attached
at an outer circumferential surface of the coupling part of the
front cover 40 (or the rear cover) to make its coupling with the
plate 50 firm as well as to prevent a leakage space that may be
generated at the coupling part with the plate 50.
[0048] FIG. 5c is a plan view showing a form of the sealing member
44c and it is noted that the shape of the sealing member 44c is
similar to the shape of the front cover. Preferably, the sealing
member 44c is made of a material with elasticity for exerting tight
coupling. The sealing member 44c should also be heat resistant for
enduring a high temperature of, for example, above 80.degree. C.,
such as heat resistant rubber or urethane, etc.
[0049] The rear protrusion 44b is formed such that it has a form
and area similar to those of the heat exchange unit 30. Preferably,
the rear protrusion 44b is also formed so that it has overall
dimensions smaller than the dimensions of the plate (to be
described in detail).
[0050] The structure of the plate 50 needs to be designed to allow
the front cover 40 (or the rear cover) and the plate to be
physically combined. The front cover 40 and/or the rear cover 42
are made of a material such as plastic formed through a general
injection molding, so a chemical bonding method through heating is
not recommended.
[0051] Thus, in one embodiment of the present invention, for the
physical coupling, the plate 50 has the structure as shown in FIG.
6. As shown in FIG. 6, a plurality of protrusions 54 are formed in
a serrated form around an outer circumference of the plate 50.
Because the protrusions 54 can be easily bent, the protrusions 54
are bent and coupled with an edge of the end of the front cover 40
so that the plate 50 can be firmly attached with the front cover
40. The rear cover 42 can also be attached in the same manner. The
bent portions of the plate can be bent around the protrusion that
extends from the cover.
[0052] Because the plate 50 is coupled with the heat exchange unit
30 by brazing or soldering, and is coupled to the front cover 40
(or the rear cover 42) in the above-described mechanical coupling
manner, the firmness of the coupling can be maintained without
degrading heat transfer characteristics. In addition, since the
plate 50 and the core of the heat exchange unit 30 can be very
quickly coupled through the brazing process, assembly time is fast,
which helps productivity. Also, because the plate 50 and the front
cover 40 (or the rear cover 42) are coupled through the physical or
mechanical method, the fabrication of the overall heat exchanger is
inexpensive.
[0053] Next, the heat exchanger according to another feature of the
present invention will now be described with reference to FIG. 8.
As shown in FIG. 8, the sealing member 45 is coupled at an outer
surface of the front cover 40 additionally or integrally. The
sealing member 45 plays an important role with respect to the
overall heat exchange system. Condensed water generated in the tube
units 32 of the heat exchange unit 30 can leak into the fin units
34. When condensed water flows into the fin units 34, external air
flow is restricted and the heat exchange operation is impaired. As
a result, the condensing efficiency of the heat exchanger is
degraded, which leads to degradation of drying efficiency of a
dryer employing the heat exchanger.
[0054] The sealing member 45 is designated to prevent condensed
water from leaking/flowing into the fin units 34. Thus, preferably,
the sealing member 45 is designated such that hot humid air inside
the dryer that flows to the tube units 32 is prevented from flowing
to the fin units 34. With reference to FIG. 9, a sealing member 45b
attached on the front cover 40, has an exterior peripheral edge
that flares outward as it approaches the heat exchanger. Likewise,
a sealing member 45b is attached on the rear cover 42 such that the
rear peripheral edges flare outward.
[0055] The two sealing members 45a and 45b are made of a material
that can endure high temperature and have excellent durability, and
preferably are made of a material such as heat resistant rubber or
urethane. The sealing members can be additionally coupled or
integrally formed on the outer circumferential surface of the front
cover 40 or the rear cover 42.
[0056] Accordingly, in a heat exchanger for a dryer embodying the
invention, the core of the heat exchange unit 30 and the front and
rear covers 40 and 42 are coupled by the plates 50. A heat
exchanger embodying the invention also prevents leakage of
condensed water, which prevents an introduction of leaked condensed
water to other components.
[0057] As so far described, the heat exchanger for a dryer
according to the present invention has many advantages as
follows.
[0058] The new coupling structure for coupling the front and rear
covers to the core can reduce the material costs be as much as 20
percent, and the manufacturing time can be considerably reduced.
This translates into economical efficiency in terms of mass
productivity and materials.
[0059] Because the front and rear covers are attached to the core
by brazing, in a very short period of time, the fabrication process
can be simplified.
[0060] In addition, because the plates and the core of the heat
exchange unit can be completely coupled and sealed, the heat
exchange performance of the heat exchanger can be improved.
[0061] When the heat exchanger is used in a dryer or a washing
machine that includes a drying function, the unit cost of the
overall system can be lowered and the drying efficiency can be
enhanced.
[0062] The foregoing embodiments and advantages are merely
exemplary and are not to be construed as limiting the present
invention. The present teaching can be readily applied to other
types of apparatuses. The description of the present invention is
intended to be illustrative, and not to limit the scope of the
claims. Many alternatives, modifications, and variations will be
apparent to those skilled in the art. In the claims,
means-plus-function clauses are intended to cover the structure
described herein as performing the recited function and not only
structural equivalents but also equivalent structures.
* * * * *