U.S. patent application number 11/449660 was filed with the patent office on 2007-01-04 for heat exchange unit.
This patent application is currently assigned to Xenesys, Inc.. Invention is credited to Toyoaki Matsuzaki, Taro Watanabe.
Application Number | 20070000654 11/449660 |
Document ID | / |
Family ID | 37074560 |
Filed Date | 2007-01-04 |
United States Patent
Application |
20070000654 |
Kind Code |
A1 |
Matsuzaki; Toyoaki ; et
al. |
January 4, 2007 |
Heat exchange unit
Abstract
A heat exchange unit includes first and second plates, which is
identical to each other in configuration in a peripheral area
thereof, but different from each other in a central irregularity
pattern section. The irregularity pattern section has a
projection-recess pattern on its surface and a recess-projection
pattern corresponding thereto on another surface. These patterns
are different from each other in configuration. The
projection-recess pattern of the first plate has a reverse
relationship in projections and recesses to the projection-recess
pattern of the second plate so as to be symmetrical to each other.
The first and second plates are placed alternately one upon another
so that the peripheral areas of the first and second plates are
directed to a same direction and projections of the irregularity
pattern section of the first plate come, on peaks thereof, into
contact with projections of the irregularity pattern section of the
second plate.
Inventors: |
Matsuzaki; Toyoaki;
(Tagata-Gun, JP) ; Watanabe; Taro; (Suginami-ku,
JP) |
Correspondence
Address: |
RADER FISHMAN & GRAUER PLLC
LION BUILDING
1233 20TH STREET N.W., SUITE 501
WASHINGTON
DC
20036
US
|
Assignee: |
Xenesys, Inc.
Hyogo-Ken
JP
|
Family ID: |
37074560 |
Appl. No.: |
11/449660 |
Filed: |
June 9, 2006 |
Current U.S.
Class: |
165/167 |
Current CPC
Class: |
F28F 2250/104 20130101;
F28D 9/0043 20130101; F28F 3/04 20130101 |
Class at
Publication: |
165/167 |
International
Class: |
F28F 3/08 20060101
F28F003/08 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 29, 2005 |
JP |
2005-190168 |
Claims
1. A heat exchange unit, comprising a plurality of heat exchange
plates having a predetermined pattern of irregularity, which are
formed of a metallic thin sheet and combined in parallel and
integrally with each other so that first spaces through which a
first heat exchange fluid is to pass and second spaces through
which a second heat exchange fluid is to pass are provided
alternately between respective heat exchange plates, wherein: said
heat exchange plates comprises first plates and second plates, said
first and second plates being substantially identical to each other
in configuration in a peripheral area thereof, but different from
each other in a central irregularity pattern section; said
irregularity pattern section of each of said first and second
plates has a projection-recess pattern on a surface thereof and a
recess-projection pattern corresponding thereto on another surface
thereof, said projection-recess pattern being different in
configuration from said recess-projection pattern so as to be
asymmetrical thereto, and the projection-recess pattern of the
first plate having a reverse relationship in projections and
recesses to the projection-recess pattern of the second plate so as
to be symmetrical to each other; and said first and second plates
are placed alternately one upon another so that the peripheral
areas of the first and second plates are directed to a same
direction, and kept apart from each other by a predetermined
distance, and projections of the irregularity pattern section of
the first plate come, on peaks thereof, into contact with
projections of the irregularity pattern section of the second
plate.
2. The heat exchange unit as claimed in claim 1, wherein: each of
said first and second plates has a shape of rectangular or square;
and at least the irregularity pattern section of each of the first
and second plates has a symmetrical shape with respect to a central
position between a pair of opposite sides of the plate or another
pair of opposite sides thereof.
3. The heat exchange unit as claimed in claim 1, wherein: the
irregularity pattern section of each of the heat exchange plates
has said projections that project outward from the surface of the
heat exchange plate in a form of a truncated cone or a truncated
pyramid, and a plurality of intermediate protrusions each of which
is placed between two projections that are adjacent to each other
at a shortest distance, each of the intermediate protrusions being
defined by one or more flat or curved portions that extend to
opposing surfaces of the two projection, and each of the
intermediate protrusions having one or more peak portions that are
placed in a lower position than a top of the projection; there is
made arrangement providing simultaneously a plurality of
combinations of the projection and another projection adjacent
thereto at the shortest distance between which the intermediate
protrusion is placed; and a plurality of non-protruded portions
each of which is placed between adjacent intermediate protrusions,
each of the non-protruded portions being placed in a lowest
position relative to a projecting direction of the projections, the
non-protruded portions providing said recesses surrounded by the
projections and the intermediate protrusions.
4. The heat exchange unit as claimed in claim 2, wherein: the
irregularity pattern section of each of the heat exchange plates
has said projections that project outward from the surface of the
heat exchange plate in a form of a truncated cone or a truncated
pyramid, and a plurality of intermediate protrusions each of which
is placed between two projections that are adjacent to each other
at a shortest distance, each of the intermediate protrusions being
defined by one or more flat or curved portions that extend to
opposing surfaces of the two projection, and each of the
intermediate protrusions having one or more peak portions that are
placed in a lower position than a top of the projection; there is
made arrangement providing simultaneously a plurality of
combinations of the projection and another projection adjacent
thereto at the shortest distance between which the intermediate
protrusion is placed; and a plurality of non-protruded portions
each of which is placed between adjacent intermediate protrusions,
each of the non-protruded portions being placed in a lowest
position relative to a projecting direction of the projections, the
non-protruded portions providing said recesses surrounded by the
projections and the intermediate protrusions.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates a heat exchange unit, which
includes a plurality of heat transfer plates, which are formed of a
metallic thin sheet and combined in parallel and integrally with
each other, and especially to such a heat exchange unit in which
fluid passages having different configurations formed between the
plates are ensured in the combined state of the plates and an
appropriate heat exchange can be made between heat exchange fluids
in correspondence with differences in characteristic properties
thereof, thus improving a heat exchange effectiveness.
[0003] 2. Description of the Related Art
[0004] If there is a demand that heat transfer coefficient is
increased to enhance heat exchange effectiveness, utilizing a heat
exchanger by which transfer of heat (i.e., heat exchange) is made
between a high temperature fluid and a low temperature fluid, a
plate-type heat exchanger has conventionally been used widely. The
plate-type heat exchanger has a structure in which a plurality of
heat transfer plates having a plate-shape are placed parallelly one
upon another at prescribed intervals so as to form passages, which
are separated by means of the respective heat transfer plate. A
high temperature fluid and a low temperature fluid flow alternately
in the above-mentioned passages to make heat exchange through the
respective heat transfer plates. An example of such a conventional
plate-type heat exchanger is discussed as a prior art in Japanese
Patent Provisional Publication No. H3-91695, with reference to
FIGS. 5 and 6 thereof.
[0005] In the conventional plate-type heat exchanger, gasket
members formed of elastic material are placed between the two
adjacent plates to make the distance between them constant and
define passages for fluid.
[0006] A pattern of irregularity of herringbone type has
conventionally and widely applied to the heat transfer plates of
the plate-type heat exchanger. However, such a pattern of
irregularity could not achieve a balance of decrease in pressure
loss and assured resistance to pressure. Accordingly, various kinds
of different pattern of irregularities have been proposed. Japanese
Patent Provisional Publication No. 2000-257488 describes an example
of such different pattern of irregularities.
[0007] The plates for the above-mentioned conventional heat
exchanger has a structure in which the plate includes a plurality
of heat transfer sections each of which has a mound configuration
provided at its top with a flat portion in a thickness direction of
the plate (i.e., a cross section thereof) and a rectangular shape
in a plan view of the plate, in the inner side of the sealing
member (i.e., the gasket member). These plates are combined to each
other so as to be placed one upon another to form a single heat
exchanger.
[0008] The conventional heat exchanger has the structure as
described in the above-mentioned prior art documents. With respect
to the conventional plates described in Japanese Patent Provisional
Publication No. 2000-257488, when manufacturing the heat exchanger,
the plates are placed one upon another to form a heat exchanger so
that alternating plates are turned upside down and upper end
portions (i.e., tip ends of projections) of heat transfer sections
of the plate faces flowing passage-intersections (i.e., root ends
of the projections) of the adjacent plate. The plates are combined
to each other so that the heat transfer sections protrude the same
direction, with the result that the flowing passages formed between
the two adjacent plates have the same pattern.
[0009] Two kinds of liquids used usually in a heat exchanger are
different from each other in chemical composition, resulting not
only in difference in characteristic property, but also in quite
difference in conditions in use such as pressure and flow rate
during a heat exchange process. It is therefore theoretically
preferable to make heat exchange, with consideration given to heat
transfer in accordance with the respective fluids. However, the
same pattern of flowing passages formed on the opposite surfaces of
the plate leads to substantially the same heat transfer conditions
for the plate. Consequently, there is no choice but to make heat
exchange under the same heat transfer conditions for the two kinds
of liquids flowing the passages. It is therefore difficult to apply
optimized heat transfer conditions in accordance with difference in
temperature and characteristic properties of the two kinds of heat
exchange liquids between which heat exchange is to be made through
the plate, thus causing a problem of no achievement of effective
heat exchange.
SUMMARY OF THE INVENTION
[0010] An object of the present invention, which was made to solve
the above-mentioned problems, is therefore to provide a heat
exchange unit, which utilizes two kinds of plates having a
symmetrical relationship in configuration of heat transfer sections
to cope with a problem of difference in characteristic properties
of fluids that flow on the opposite surfaces of the plate,
respectively, and ensure sufficient heat transfer performance, thus
obtaining a high heat exchange efficiency.
[0011] In order to attain the aforementioned object, a heat
exchange unit according to the first aspect of the present
invention, comprises a plurality of heat exchange plates having a
predetermined pattern of irregularity, which are formed of a
metallic thin sheet and combined in parallel and integrally with
each other so that first spaces through which a first heat exchange
fluid is to pass and second spaces through which a second heat
exchange fluid is to pass are provided alternately between
respective heat exchange plates, wherein: the heat exchange plates
comprises first plates and second plates, the first and second
plates being substantially identical to each other in configuration
in a peripheral area thereof, but different from each other in a
central irregularity pattern section; the irregularity pattern
section of each of the first and second plates has a
projection-recess pattern on a surface thereof and a
recess-projection pattern corresponding thereto on another surface
thereof, the projection-recess pattern being different in
configuration from the recess-projection pattern so as to
asymmetrical thereto, and the projection-recess pattern of the
first plate having a reverse relationship in projections and
recesses to the projection-recess pattern of the second plate so as
to be symmetrical to each other; and the first and second plates
are placed alternately one upon another so that the peripheral
areas of the first and second plates are directed to a same
direction, and kept apart from each other by a predetermined
distance, and projections of the irregularity pattern section of
the first plate come, on peaks thereof, into contact with
projections of the irregularity pattern section of the second
plate.
[0012] According to the first aspect of the present invention,
there are used two kinds of plates for the heat exchange plates,
i.e., the first and second plates that are substantially identical
to each other in configuration in a peripheral area thereof, but
provided with the respective central irregularity pattern sections
that are symmetrical to each other so as to have the reverse
relationship in projection-recess pattern. Assembling such two
kinds of plates, i.e., the first and second plates by placing
alternately them one upon another so that the peripheral areas of
the first and second plates are directed to the same direction, and
fastening them, with gasket members placed between the peripheral
areas of the plates or brazing them at the contacting peripheral
areas thereof provides two kinds of gaps formed between the plates,
which gaps are different in configuration and size on the opposite
surface sides of the plate in accordance with the adjacently
combined two plates having the central irregularity pattern
sections. Two adjacent gaps provide flow passages having different
characteristics from each other, thus causing different heat
transfer performances. Formation of the flow passages in accordance
with characteristic properties of heat exchange fluids makes it
possible to cause heat transfer between the plates and the heat
exchange fluids to effectively progress, thus making an effective
heat exchange between the fluids. In the combined states of the
plates in which the projections of the adjacent plates come into
contact with each other, and in addition, projections formed on the
backsides of the recesses come into contact with each other. The
plates can be brought into contact with each other not only at the
peripheral areas, but also at a number of connecting areas in the
irregularity pattern sections of the plates. The irregularity
pattern section of the heat exchange plate can be held by the two
other adjacent plates, so as to improve remarkably strength of the
unit, thus maintain the appropriate configurations of the gaps to
perform a proper heat exchange, even when heat exchange fluids
introduced into the gaps between the plates have high pressure.
[0013] In the second aspect of the heat exchange unit of the
present invention, there may be adopted a structure in which each
of the first and second plates has a shape of rectangular or
square; and at least the irregularity pattern section of each of
the first and second plates has a symmetrical shape with respect to
a central position between a pair of opposite sides of the plate or
another pair of opposite sides thereof.
[0014] According to the second aspect of the present invention, the
irregularity pattern section of each of the first and second plates
has a symmetrical shape with respect to a central position between
a pair of opposite sides of the plate or another pair of opposite
sides thereof Tuning the plate inside out provides a reverse
relationship in projection-recess pattern with respect to that of
the plate as not turned, with the positions of the projections and
recesses unchanged, thus permitting to provide the same
configuration of the irregularity pattern section as the other
plate not turned. It is therefore possible to use the same
press-forming die for at least the irregularity pattern section in
a press-forming method so as to manufacture the heat exchange
plates. As a result, the same die can be applied to the
irregularity pattern section having a complicated configuration in
manufacture of two kinds of different plates, thus reducing costs
and remarkably improving production efficiency.
[0015] In the third aspect of the heat exchange unit of the present
invention, there may be adopted a structure in which the
irregularity pattern section of each of the heat exchange plates
has the projections that project outward from the surface of the
heat exchange plate in a form of a truncated cone or a truncated
pyramid, and a plurality of intermediate protrusions each of which
is placed between two projections that are adjacent to each other
at a shortest distance, each of the intermediate protrusions being
defined by one or more flat or curved portions that extend to
opposing surfaces of the two projection, and each of the
intermediate protrusions having one or more peak portions that are
placed in a lower position than a top of the projection; there is
made arrangement providing simultaneously a plurality of
combinations of the projection and another projection adjacent
thereto at the shortest distance between which the intermediate
protrusion is placed; and a plurality of non-protruded portions
each of which is placed between adjacent intermediate protrusions,
each of the non-protruded portions being placed in a lowest
position relative to a projecting direction of the projections, the
non-protruded portions providing the recesses surrounded by the
projections and the intermediate protrusions.
[0016] According to the third aspect of the present invention, the
irregularity pattern section of each of the heat exchange plates
has the projections that project outward from one surface of the
heat exchange plate in a form of a truncated cone or a truncated
pyramid, and the plurality of intermediate protrusions each of
which is placed between two projections that are adjacent to each
other at a shortest distance. When the heat exchange plates are
arranged in parallel with each other, there is provided between the
two adjacent plates a gap in which a unit of the similar pattern of
irregularity is repeated in aligning directions of the projections,
thus providing linear passages extending in the above-mentioned
directions so as to cross each other. More specifically, each of
the linear passages extending in a reticulation shape includes
expanded areas and throat areas that are placed alternately in the
same direction, on the one hand, and the linear passage extending
in the perpendicular direction to the above-mentioned direction
includes expanded areas and throat areas that are placed
alternately in the same perpendicular direction, in the similar
manner. Using the thus assembled plates can impart substantially
the same behavior to the heat exchange fluid, irrespective the
flowing system of the heat exchange fluid, i.e., any one of the
parallel flowing system, the counter-flowing system and the cross
flowing system. As a result, it is possible to perform a smooth
heat transfer at a low pressure loss to make an effective heat
exchange, even when the heat exchange fluids are combined in any
manner in their flowing directions, thus providing a high degree of
freedom in design of the heat exchanger and becoming excellent in
general purpose use. In addition, the heat exchange fluid ca flow
freely in the above-mentioned two directions along the plate, and
the constant heat transfer property can be obtained, irrespective
of the flowing direction of the heat exchange fluid. It is
therefore possible to cause the heat exchange fluid to spread over
the entire area of the plate so that such an entire area can serve
as an effective heat transfer section, and vary flowing conditions
through the intermediate protrusions in comparison with a simple
combination of cones or pyramids so as to provide an improved heat
transfer, thus increasing remarkably an amount of heat transfer per
area and achieving a high performance. Further, the projections of
the plate, which come into contact with the other plate, are
provided in the form of the truncated cone or truncated pyramid so
as to disperse force applied to the projections in the direction on
the surface the truncated cone or truncated pyramid. As a result,
the strength of the assembled plates can be improved remarkably in
comparison with the conventional heat exchange plate, and it is
therefore possible to keep the distance between the two adjacent
plates constant, even when there exists a large difference in
pressure between the heat exchange fluids, thus enhancing a
pressure-resistant property.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a plan view illustrating a schematic structure of
the first plate of a heat exchange unit according to an embodiment
of the present invention;
[0018] FIG. 2 is a plan view illustrating a schematic structure of
the second plate of a heat exchange unit according to an embodiment
of the present invention;
[0019] FIG. 3 is a perspective view illustrating a state in which
the heat exchange plates for the heat exchange unit according to
the embodiment of the present invention are arranged;
[0020] FIG. 4 is a side view illustrating a state in which the heat
exchange plates are assembled into the heat exchange unit according
to the embodiment of the present invention;
[0021] FIG. 5 is an enlarged partial view of the first plate of the
heat exchange unit according to the embodiment of the present
invention;
[0022] FIG. 6 is a cross-sectional view cut along the line VI-VI in
FIG. 5;
[0023] FIG. 7 is a cross-sectional view cut along the line VII-VII
in FIG. 5;
[0024] FIG. 8 is a cross-sectional view cut along the line
VIII-VIII in FIG. 5;
[0025] FIG. 9 is an enlarged partial view of the second plate of
the heat exchange unit according to the embodiment of the present
invention;
[0026] FIG. 10 is a cross-sectional view cut along the line X-X in
FIG. 9;
[0027] FIG. 11 is a cross-sectional view cut along the line XI-XI
in FIG. 9;
[0028] FIG. 12 is a cross-sectional view cut along the line XII-XII
in FIG. 9; and
[0029] FIG. 13 is an enlarged partial cross-sectional view
illustrating the irregularity pattern sections of the heat exchange
plates for the heat exchange unit according to the embodiment of
the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] Now, the embodiment of the present invention will be
described in detail below with reference to FIGS. 1 to 13. FIG. 1
is a plan view illustrating a schematic structure of the first
plate of a heat exchange unit according to an embodiment of the
present invention; FIG. 2 is a plan view illustrating a schematic
structure of the second plate of a heat exchange unit according to
an embodiment of the present invention; FIG. 3 is a perspective
view illustrating a state in which the heat exchange plates for the
heat exchange unit according to the embodiment of the present
invention are arranged; FIG. 4 is a side view illustrating a state
in which the heat exchange plates are assembled into the heat
exchange unit according to the embodiment of the present invention;
FIG. 5 is an enlarged partial view of the first plate of the heat
exchange unit according to the embodiment of the present invention;
FIG. 6 is a cross-sectional view cut along the line VI-VI in FIG.
5; FIG. 7 is a cross-sectional view cut along the line VII-VII in
FIG. 5; FIG. 8 is a cross-sectional view cut along the line
VIII-VIII in FIG. 5; FIG. 9 is an enlarged partial view of the
second plate of the heat exchange unit according to the embodiment
of the present invention; FIG. 10 is a cross-sectional view cut
along the line X-X in FIG. 9; FIG. 11 is a cross-sectional view cut
along the line XI-XI in FIG. 9; FIG. 12 is a cross-sectional view
cut along the line XII-XII in FIG. 9; and FIG. 13 is an enlarged
partial cross-sectional view illustrating the irregularity pattern
sections of the heat exchange plates for the heat exchange unit
according to the embodiment of the present invention.
[0031] The heat exchange unit 1 according to the embodiment of the
present invention is composed of two kinds of heat exchange plates
10, 20, which serve as the first and second plates, respectively,
and are placed in parallel with each other through gasket members
60 and combined together. The heat exchange plates 10, 20 have
irregularity pattern sections 30, 40 and peripheral areas 50 with
which the irregularity pattern sections 30, 40 are surrounded,
respectively. Each of the plates 10, 20 has opposite surfaces,
which are to be come into contact with heat exchange fluids,
respectively.
[0032] The heat exchange plates 10, 20, which are formed of a
metallic thin sheet having a rectangular shape, are subjected to a
press forming process to form irregularity pattern sections 30, 40
in a central portion thereof and the peripheral areas 50 by which
the irregularity pattern sections 30, 40 are surrounded,
respectively. The irregularity pattern section 30 of the first heat
exchange plate 10 has a reverse relationship in projections and
recesses to the irregularity pattern section 40 of the second heat
exchange plate 20 so as to be symmetrical to each other. As a
result, the heat exchange plates 10, 20 are provided in the form of
two different kinds of plates that are identical to each other in
configuration of the peripheral area 50, but different from each
other in configuration in the central irregularity pattern sections
30, 40 having the reverse relationship in projections and recesses
therein to each other.
[0033] The first heat exchange plate 10 has openings 11, 12, 13, 14
formed at four corners of the plate on the inside of the peripheral
area 50, respectively in the same manner as the conventional plate,
so as to enable a heat exchange fluid to pass through therein. The
second heat exchange plate 20 also has openings 21, 22, 23, 24
formed in the same manner.
[0034] The above-mentioned irregularity pattern sections 30, 40
have a common fundamental configuration in projection-recess
pattern. The above-mentioned irregularity pattern section 30
includes a plurality of projections 31, a plurality of intermediate
protrusions 33 and a plurality of recesses 34. The projections 31
are formed on the basis of a matrix arrangement in which the
projections 13 project in the form of truncated pyramid from the
surface of the plate so that four pyramidal surfaces of the
projection faces the respective surrounding pyramidal surfaces of
the adjacent projections and are aligned at regular intervals in
four directions corresponding to the four pyramidal surfaces of the
projection. Each of the intermediate protrusions 33 is placed in
the form of a mound portion between the opposing pyramidal surfaces
of the two adjacent projections 31 so that a pair of foot portions
of the intermediate protrusion is located in the lowest positions
at which corresponding ridgelines of the opposing pyramidal
surfaces intersect and a peak portion of the intermediate
protrusion is located between the intersecting points of the
above-mentioned ridgelines. The peak portion of the intermediate
protrusion 33 is placed in a lower position than the top 32 of the
projection 31. Each of the recesses 34 is provided in the form of a
non-protruded portion in a central position between the projections
that are placed adjacently to each other without placing the
intermediate protrusion 33 therebetween. The recess 34 is
surrounded by the pyramidal surfaces of the projections 31 and
inclines surfaces of the intermediate protrusions 33 so as to be
placed in the lowest position in the direction perpendicular to the
plane of the plate.
[0035] The irregularity pattern section 40, which is symmetrical to
the irregularity pattern section 30 on assumption that the
peripheral areas of the heat exchange plates 10, 20 face to the
same direction, includes a plurality of recesses 41, a plurality of
intermediate valley portions 42 and a plurality of projections 43.
The recesses 41 are formed on the basis of a matrix arrangement so
as to dent in the form of a truncated pyramid. Each of the
intermediate valley portion 42 is placed in the form of a dent
portion between the opposing pyramidal surfaces of the two adjacent
recesses 41 so that a bottom of the intermediate valley portion 42
is located in an upper position than the bottom of the recess 41.
Each of the projections 43 is provided, in the highest place in the
direction perpendicular to the plane of the plate, between the
recesses 41 that are placed adjacently to each other without
placing the intermediate valley portion 42 therebetween. The
recesses 41 of the irregularity pattern section 40 match with the
configuration just on the backside of the projections 31 of the
irregularity pattern section 30. The intermediate valley portions
42 match with the configuration on the backside of the intermediate
protrusions. The projections 43 match with the configuration on the
backside of the recesses 34.
[0036] The projection 31 and the recess 34 are placed so as to
deviate from each other by a half of a distance between two
adjacent projections in the alignment direction thereof. The recess
41 and the projection 43 are also placed so as to deviate from each
other by a half of a distance between two adjacent projections in
the alignment direction thereof. The projections 31, 43 and the
recesses 34, 41 are formed at regular intervals based on a matrix
arrangement. However, in the above-mentioned irregularity pattern
sections 30, 40, recess portions formed on the backsides of the
projections 31, 42 are different in configuration from the recesses
34, 41 and projections portions formed on the backsides of the
recesses 34, 41 are different in configuration from the projections
31, 43. The opposite surfaces of each of the plates having the
irregularity pattern section are asymmetrical to each other.
[0037] In addition, not only the direction along which the two
adjacent projections 31 of the irregularity pattern section 30 are
aligned so as to place the recess 34 therebetween, but also the
direction along which the two adjacent recesses 41 of the
irregularity pattern section 40 are aligned so as to place the
projection 43 therebetween are in parallel with or perpendicular to
the side of the rectangular plate. The irregularity pattern
sections 30, 40 may have a structure in which the above-mentioned
directions are inclined by an angle of 45 degrees or a desired
angle relative to the side of the plate.
[0038] The peripheral area 50 of each of the heat exchange plates
10, 20 is provided in the form of a flat portion along the
respective side edges. The plates are placed on upon another so as
to face to the same direction, with gasket members 60 placed
between the peripheral areas 50 of the plates. The surface of the
heat exchange plate 10, from which the projections 31 project,
serves as a front surface, and the surface of the heat exchange
plate 20, from which the projections 43 project, serves as a front
surface.
[0039] The heat exchange plates 10, 20 are placed one upon another
with the front surfaces thereof directed to the same direction and
combined together into a heat exchange unit 1. In such an assembled
state, the peripheral areas 50 of the adjacent two plates 10, 20
come into contact with each other, the projections 31 of the
irregularity pattern section 30 the heat exchange plate 10 come
into contact with the projection portions formed on the backsides
of the recesses 41 of the irregularity pattern section 40 of the
heat exchange plate 20, and the projection portions formed on the
backsides of the recesses 34 of the irregularity pattern section 30
of the heat exchange plate 10 come into contact with the
projections 43 of the irregularity pattern section 40 of the other
heat exchange plate 20. As a result, a gap in which a heat exchange
fluid is to flow is formed between the two adjacent plates 10, 20,
excluding the contacting portions thereof.
[0040] In the first gap section 61 in which the projections 31 of
the irregularity pattern section 30 project, the intermediate
protrusions 33 having a smaller height than the projections 31 face
the backsides of the corresponding intermediate valley portions 42,
with a constant distance kept therebetween, and the recesses 34
having a further smaller height than the intermediate valley
portions 42 face the backsides of the corresponding projections 43,
with another constant distance kept therebetween. The gap section
formed on the front surface side of the intermediate protrusions 33
communicates with the gap section formed on the front surface side
of the recesses 34 to form linear passages. Each of the linear
passages, which has a passage opening increasing from the
intermediate protrusion 33 toward the recess 34, includes expanded
areas and throat areas that are placed alternately to extend
linearly, on the one hand, and the linear passage extending in the
perpendicular direction to the above-mentioned direction includes
expanded areas and throat areas that are placed alternately in the
same perpendicular direction, in the similar manner. The first gap
section 61 communicates with the other first gap section 61 and the
outside at the openings 11, 13, 21, 23 provided at two corners on
the same side of the heat exchange plates 10, 20.
[0041] In the second gap section 62 in which the projections 43 of
the irregularity pattern section 40 project, a tunnel-shaped gap
section formed between the intermediate valley portion 42 and the
backside of the corresponding intermediate protrusion 33 connects
spaces provided between the recesses 41 and the backsides of the
corresponding projections 31 to each other, so as to form linear
passages. Each of the linear passages, which has a passage opening
increasing from the intermediate protrusion 42 toward the recess
41, includes expanded areas and throat areas that are placed
alternately to extend linearly in the direction along which the
recesses 41 are aligned, on the one hand, and the linear passage
extending in the perpendicular direction to the above-mentioned
direction includes expanded areas and throat areas that are placed
alternately in the same perpendicular direction, in the similar
manner. The second gap section 62 communicates with the other
second gap section 62 and the outside at the openings 12, 14, 22,
24 provided at the other corners than those provided with the
above-mentioned openings 11, 13, 21, 23.
[0042] The opposite surfaces of each of the first and second plates
having the projection-recess pattern are asymmetrical from each
other and the first and second plates are placed alternately one
upon another so that the corresponding surfaces of these plates,
which are symmetrical to each other, face to each other, and
combined together into a unit. As a result, the first gap section
61 and the second gap section 62 are different from each other in
configuration and size. Differences between the first gap section
61 and the second gap section 62 in configuration and size impart
these sections different heat transfer properties. Previously
forming of the projection-recess patterns of the plates to
determine the configuration and size of the gap sections taking
into consideration characteristic properties of two kinds of fluids
between which heat exchange is to be made makes it possible to
provide suitable flowing conditions and heat transfer properties
for these fluids. The heat exchanger is designed so that the heat
exchange fluids having the respective characteristic properties are
introduced into the corresponding first and second gap sections 61,
62, respectively.
[0043] The heat exchange plates 10, 20 have further additional
features that each of these plates is symmetrical in areas of the
opening and the irregularity pattern sections 30, 40 with respect
to a center of the short sides of the plate. Accordingly, turning
the first heat exchange plate 10 inside out by an angle of 180
degrees so that the long sides of the plate change their places
provides a state in which only a relationship in projections and
recesses is reversed relative to the plate as not-turned, with
places of the projection and recesses kept unchanged. The thus
turned plate 10 and the other plate 20 as not-turned are identical
to each other in an area inside the peripheral areas 50.
[0044] A design is made so that, when the first plate is turned
inside out, the same configuration as the second plate in the
predetermined area containing the irregularity pattern sections 30,
40 can be obtained. It is therefore possible to form the
irregularity pattern sections 30, 40 for the two kinds of heat
exchange plates 10, 20 in the same manner. In this case, it is
possible to form such sections 30, 40 by using a press-forming
apparatus in which portions of a die of the press-forming apparatus
corresponding to the peripheral areas 50 of the plate can be
adjusted in position relative to the other portions, for example a
press-forming apparatus an invention of which was made by the
inventors of the present invention and described in Japanese Patent
Provisional Publication No. 2003-275824. In use of such an
apparatus, a positional adjustment of auxiliary die sections for
forming the peripheral areas 50 relative to a central main die
section for forming the irregularity pattern sections 30, 40 in a
pressing direction is made in the pressing apparatus and then, a
press forming process is carried out. In such a case, it is
possible to manufacture the two different kinds of plates with the
use of the same dies, thus providing a remarkably enhanced
manufacturing efficiency.
[0045] Now, assembling steps for the heat exchange unit according
to the present invention will be described below. It is assumed
that the two kinds of heat exchange plates 10, 20, i.e., a
plurality of plates 10 and a plurality of plates 20, which have the
same configuration in the peripheral area 50, but the symmetrical
irregularity pattern sections 30, 40 in the central portion thereof
have previously been prepared by a press-forming method.
[0046] The heat exchange plates 10, 20 in a predetermined number
are alternately one upon another, with gasket members 60 placed
between the peripheral areas 50 of the plates and peripheries of
the openings, and then fastened from the opposing directions in the
aligning direction of the plates to prepare a heat exchange unit 1
in which all the plates are water-tightly combined together, in the
same manner as the conventional plate-type heat exchanger, except
that the heat exchange plates 10, 20 are alternately one upon
another so that the plates 10 are turned inside out relative to the
plates 20 and the long sides of each plates 10 change their places,
as a result that the surfaces for defining the irregularity pattern
sections 30, 40, respectively face each other.
[0047] In the thus obtained heat exchange unit 1, the first gap
section 61 is formed on the side of the projections 31 of each heat
exchange plate 10 and the openings 11, 13, 21, 23 communicate with
this first gap section 61. The second gap section 62 is formed on
each sides placed adjacently to the first gap section 61 through
the heat exchange plates 10, 20 and the openings 12, 14, 22, 24
communicate with this second gap section 62. When the heat exchange
unit 1 composed of the plates as combined in a manner as described
above is placed in use so that one of the both sides of each plate
is placed horizontally or vertically, the main passages in the gap
sections 61, 62 between the plates, i.e., the gaps continuously
extending along the recesses 34 and the intermediate protrusions 33
of the heat exchange plate 10, and the gaps continuously extending
along the recesses 41 and the intermediate valley portions 42 of
the heat exchange plate 20 are kept in an inclined state.
[0048] Now, an operation of the heat exchange unit according to the
embodiment of the present invention serving as the heat exchanger
will be described below. A heat exchange fluid is introduced into
the first gap section 61 through the two openings 11, 13, 21, 23 of
the respective heat exchange plates 10, 20 for forming the heat
exchange unit 1, and discharged therefrom, on the one hand, and
another heat exchange fluid is introduced into the second gap
section 62 through the remaining two openings 12, 14, 22, 24 of the
respective heat exchange plates 10, 20, and discharged therefrom,
on the other hand.
[0049] In the gap sections 61, 62 in which the heat exchange fluids
flow, the passages linearly extend in the oblique direction along
which the projections 31, 42 and the recesses 34, 41 are aligned,
mainly around the recesses and the intermediate protrusions 33 or
the intermediate valley portions 42. The heat exchange fluids flow
in the above-mentioned passages. As a result, the heat exchange
fluids flows in the oblique direction in the passages that have
specific configurations with the repeated expanded areas and throat
areas in the gap sections 61, 62, and naturally repeats divergence
and confluence to smoothly spread over every areas on the upper and
lower surfaces of the plate of the irregularity pattern sections
30, 40 of the heat exchange plates 10, 20. Even when a flowing
relationship of the two kinds of heat exchange fluids is based on
any one of a parallel flowing system, a counter-flowing system and
a cross flowing system, it is therefore possible to impart
substantially the same conditions to the heat exchange fluids and
reduce pressure loss and achieve smooth flow of the heat exchange
fluids.
[0050] The heat exchange fluids spread over every area in the gap
sections 61, 62 formed between the plates, to improve heat transfer
between the plates and the heat exchange fluids. In addition, the
heat exchange fluids spread over every area in the gap sections 61,
62 that are formed between the plates and have the specific shapes
in which expanded areas and throat areas are placed alternately,
thus providing the opposite surfaces of each plate with the
respective passages having the different configurations from each
other for heat transfer properties in full consideration of the
characteristic properties of the heat transfer fluids. It is
therefore possible to cause an effective heat transfer to progress
between the respective heat exchange fluids flowing through the gap
sections and the respective heat exchange plates 10, 20, with the
result that heat exchange can be made smoothly between the heat
exchange fluids through the heat exchange plates 10, 20.
[0051] According to the heat exchange unit of the embodiment of the
present invention, there are used two kinds of plates for the heat
exchange plates 10, 20, i.e., the first and second plates that are
substantially identical to each other in configuration in a
peripheral area thereof, but provided with the respective central
irregularity pattern sections 30, 40 that are symmetrical to each
other so as to have the reverse relationship in projection-recess
pattern. Assembling such two kinds of plates, i.e., the first and
second plates by placing alternately them one upon another so that
the peripheral areas 50 of the first and second plates are directed
to the same direction, and fastening them, with gasket members 60
placed between the peripheral areas 50 of the plates 10, 20 two
kinds of gaps 61, 62 formed between the plates, which gaps are
different in configuration and size on the opposite surface sides
of the plate in accordance with the adjacently combined two plates
having the central irregularity pattern sections. Two adjacent gaps
provide flow passages having different characteristics from each
other, thus causing different heat transfer performances. Formation
of the flow passages in accordance with characteristic properties
of heat exchange fluids makes it possible to cause heat transfer
between the plates and the heat exchange fluids to effectively
progress, thus making an effective heat exchange between the
fluids.
[0052] In the heat exchange unit according to the embodiment of the
present invention, the irregularity pattern section 30 has a basic
structure in which the projection 31 is surrounded by four adjacent
projections 31 through the intermediate protrusions 33 and the
recesses 34 are placed so as to deviate from the projections by a
half of the distance between the two adjacent projections and the
irregularity pattern sections 40 also have the similar arrangement.
However, the present invention is not limited only to such an
embodiment. Any desired structure may be adopted, except for the
specific design in which the irregularity pattern sections 30, 40
of the heat exchange plates 10, 20 have the symmetrical
configurations to each other, and for example, there may be made
adjustment in shape of the projections of the irregularity pattern
section, existence or inexistence of the intermediate protrusions
between the projections, the number of the other projections by
which the projection is surrounded. Such a modified structure
permits adjustment to cope appropriately with the characteristic
properties of the heat exchange fluids introduced into the gaps
between the plates.
[0053] In the heat exchange unit according to the embodiment of the
present invention, each of the projections 31 of the irregularity
pattern section 30 has a truncated pyramid shape. However, the
projection may have a shape of prismoid such as a pentagonal
prismoid or a hexagonal prismoid, or a shape of truncated cone so
as to be adapted to the desired performance of the heat
exchanger.
[0054] In the heat exchange unit according to the embodiment of the
present invention, the two kinds of plates having the irregularity
pattern sections 30, 40 that are symmetrical in configuration to
each other are used in the type of the heat exchange unit in which
the heat exchange plates 10, 20 are placed alternately one upon
another, with the gasket members 60 placed between the plates.
However, the present invention is not limited only to such an
embodiment. In case where the plates are placed in parallel with
each other and brazed in a water-tight manner, it is also possible
to use two kinds of plates, which are identical to each other in
configuration in the peripheral areas thereof, but symmetrical to
each other in the irregularity pattern sections thereof, thus
providing the heat exchange unit having the same heat exchange
properties as the heat exchange unit as described above and a high
pressure proof property.
* * * * *