U.S. patent application number 11/260322 was filed with the patent office on 2006-05-11 for heat exchanger core with expanded metal spacer component.
This patent application is currently assigned to VENMAR VENTILATION INC.. Invention is credited to Benoit Arpin, Frederick Bedard, Michel Julien, Pierre Nadeau.
Application Number | 20060096746 11/260322 |
Document ID | / |
Family ID | 36315134 |
Filed Date | 2006-05-11 |
United States Patent
Application |
20060096746 |
Kind Code |
A1 |
Arpin; Benoit ; et
al. |
May 11, 2006 |
Heat exchanger core with expanded metal spacer component
Abstract
A plate-type heat exchanger element for a plate-type air to air
heat exchanger. The heat exchanger element comprises a heat
exchange partition sheet and a spacer member comprising a
corrugated mesh of expanded sheet metal. The corrugated mesh has an
upstream side edge and a downstream side edge. The upstream side
edge and the downstream side edge are folded over edges.
Inventors: |
Arpin; Benoit;
(Drummondville, CA) ; Bedard; Frederick;
(Ste-Clothilde-de-Horton, CA) ; Julien; Michel;
(Drummondville, CA) ; Nadeau; Pierre;
(Drummondville, CA) |
Correspondence
Address: |
BCF LLP
25th Floor
1100 Rene-Levesque Boulevard West
Montreal
QC
H3B 5C9
CA
|
Assignee: |
VENMAR VENTILATION INC.
|
Family ID: |
36315134 |
Appl. No.: |
11/260322 |
Filed: |
October 28, 2005 |
Current U.S.
Class: |
165/166 |
Current CPC
Class: |
F28D 9/0062 20130101;
F28D 21/0015 20130101; F28F 3/027 20130101; F24F 13/30
20130101 |
Class at
Publication: |
165/166 |
International
Class: |
F28F 3/00 20060101
F28F003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 9, 2004 |
CA |
2,487,459 |
Claims
1. A plate-type air to air heat exchanger, comprising a plurality
of stacked heat exchange partition sheets, each partition sheet
being spaced apart from an adjacent partition sheet by respective
spacing apart means so as to thereby form a plurality of first and
second passageways for a first air stream and a second air stream
to pass there through, respectively; means for sealing two opposing
sides of said first passageways thereby allowing the first air
stream to pass there through in a first direction; means for
sealing two opposing sides of said second passageways thereby
allowing the second air stream to pass there through in a second
direction and wherein said spacing apart means for each of said
first and second passageways comprises a corrugated mesh of
expanded sheet metal having an upstream side edge and a downstream
side edge characterized in that said upstream side edge and said
downstream side edge are folded over edges.
2. A plate-type heat exchanger as defined in claim 1 wherein said
partition sheets are of material having heat conductivity and
moisture permeability.
3. A plate-type heat exchanger as defined in claim 1 wherein said
corrugated mesh is of aluminum.
4. A plate-type heat exchanger as defined in claim 2 wherein said
partition sheets are of paper and said corrugated mesh is of
aluminum.
5. A plate-type heat exchanger element for a plate-type air to air
heat exchanger, said heat exchanger element comprising a heat
exchange partition sheet and a spacer member, said spacer member
comprising a corrugated mesh of expanded sheet metal, said
corrugated mesh having an upstream side edge and a downstream side
edge characterized in that said upstream side edge and said
downstream side edge are folded over edges.
6. A plate-type heat exchanger element as defined in claim 5
wherein said partition sheet is of material having heat
conductivity and moisture permeability.
7. A plate-type heat exchanger element as defined in claim 5
wherein said corrugated mesh of aluminum.
8. A plate-type heat exchanger element as defined in claim 5
wherein said partition sheet is of paper and said corrugated mesh
is of aluminum.
9. A plate-type heat exchanger element for a plate-type air to air
heat exchanger, said heat exchanger element comprising a heat
exchange partition sheet and a spacer member, said spacer member
comprising a corrugated mesh of expanded sheet metal, said
corrugated mesh having an upstream side edge, a downstream side
edge and a pair of opposed wall side edges connecting said upstream
side edge to said downstream side edge, characterized in that said
upstream side edge and said downstream side edge are folded over
edges and said heat exchange partition sheet is attached to said
corrugated mesh at each of said wall side edges so as to define an
exchanger air flow barrier element.
10. A plate-type heat exchanger element as defined in claim 9
wherein said partition sheet is of material having heat
conductivity and moisture permeability.
11. A plate-type heat exchanger element as defined in claim 9
wherein said corrugated mesh is of aluminum.
12. A plate-type heat exchanger element as defined in claim 9
wherein said partition sheet is of paper and said corrugated mesh
is of aluminum.
13. A spacer member for a plate-type air to air heat exchanger,
said spacer member comprising a corrugated mesh of expanded sheet
metal having an upstream side edge and a downstream side edge
characterized in that said upstream side edge and said downstream
side edge are folded over edges.
14. A spacer member as defined in claim 13 wherein said corrugated
mesh is of aluminum.
Description
[0001] The present invention relates to air to air heat exchangers
for use in a ventilation system able to provide fresh air to an
enclosure, such as for example, the interior of one or more rooms
of a house or building. Thus, the invention is concerned with a
heat exchanger which can exchange heat between the outgoing air
discharged to the outside and the incoming air introduced from the
outside of an enclosure to thereby recover the heat which otherwise
is carried away by the outgoing air.
[0002] More particularly, the present invention relates to
plate-type air to air heat exchangers which are capable of
exchanging actual (i.e. sensible) heat or a combination of actual
heat and latent heat (i.e. humidity) between outgoing air and
incoming fresh air in relation to an enclosure. The following will,
however, by way of example only, discuss the invention in relation
to the transfer of sensible heat and humidity between discharge air
and fresh air.
[0003] Plate-type air to air heat exchangers are known; such
exchangers are for example described in U.S. Pat. Nos. 4,022,050,
4,040,804, 4,051,898, 4, 377, 400, 4,434,835, 4,460,388, 4,848,450,
6,394,179, and 6,536,514 as well as U.S. patent application Ser.
No. 10/160,370 published under no. 2002/0185266 and carrying a
publication date of Dec. 12, 2002 (the entire contents of these
patent documents are incorporated herein by reference). See also
U.S. Pat. Nos. 3,931,854, 4,016,928, 4,966,231, 5,279,361,
5,474,639, and 6,032,730 (the entire contents of these patent
documents are also incorporated herein by reference).
[0004] Plate-type air to air heat exchangers generally comprise a
plurality of stacked heat exchange partition sheets or plates. Each
partition plate or sheet may for example be spaced apart from an
adjacent partition sheet or plate by respective spacing apart means
so as to thereby form a plurality of first and second passageways
(e.g. alternating first and second passageways) for a first air
stream and a second air stream to pass there through, respectively.
This type of known exchanger also comprises means for sealing two
opposing sides of the first passageways thereby allowing the first
air stream to pass there through in a first direction; and
additional means for sealing two opposing sides of said second
passageways thereby allowing the second air stream to pass there
through in a second direction.
[0005] Thus, a plate-type heat exchanger may create or define
alternating flow passageways for the fresh air stream and exhaust
air stream to pass there through. The flow passageways are
typically either parallel or perpendicular to one another (e.g. for
counter flow or for cross flow of air there through). For a cross
flow heat exchanger, the alternating flow passages are generally
perpendicular to one another. However, if the alternating flow
passageways are parallel to one another and the air streams flow in
the same direction, then the heat exchanger may be referred to as a
co-flow heat exchanger. Additionally, if the alternating flow
passageways are parallel to one another but the air streams flow in
opposite directions, then the heat exchanger may be referred to as
a counter flow heat exchanger.
[0006] In any event regardless of the direction of the air flow
patterns, as the outgoing and incoming air streams pass through
respective passageways and along opposite sides of the heat
exchange plates or sheets, the heat or energy in one air stream is
transferred to the other air stream. Depending upon the material of
the plates or sheets, the plates or sheets can transfer sensible
heat or both sensible and latent heat. Specifically, the plates or
sheets may be made of a material that is only capable of
transferring sensible heat. On the other hand, the plates or sheets
may be made of a material that is capable of transferring latent
heat, as well as sensible heat. For example, metal plates or
sheets, such as aluminum plates, absorb a portion of the thermal
energy in one air stream and transfer such energy to the other air
stream without allowing any moisture to pass there through.
Alternatively, the plates or sheets may be made of paper capable of
transferring sensible heat as well as latent heat (i.e. moisture)
between air streams. Such paper materials suitable for such
exchanger plates or sheets are for example described in U.S. Pat.
Nos. 4,040,804 and 4,051,898; the paper may for example be Japanese
paper.
[0007] It is also known to use a corrugated mesh of expanded sheet
metal as a spacer member to space apart adjacent exchanger plates
or sheets.
[0008] Expanded metal is a well-known commercial item and may, for
example, be fabricated from a roll of sheet metal (e.g. metal foil)
by cutting a plurality of rows of slits in the sheet metal stock,
the slits of each row of slits being offset from those of the
adjacent rows by half the distance between slits, and then exerting
a tensile stress across the sheet metal stock perpendicular to the
slits therein to expand the metal by opening the slits to create
the plurality of openings or apertures therein, i.e. to create an
expanded metal sheet mesh. See for example U.S. Pat. Nos. 4,016,928
and 6,629,016. Expanded metal may be formed from many metals, e.g.
aluminum and copper. See also U.S. Pat Nos. 4,315,356, 4,526,347,
4,921,118, and 5,302,466, (the entire contents of these patent
documents are incorporated herein by reference).
[0009] A roll of expanded sheet metal mesh may, for example, be cut
into appropriately sized essentially flat or planar sheet metal
mesh elements. These sheet metal mesh elements may be passed
through the nip of a pair of opposed rollers having alternating
male and female elements which are configured to provide the sheet
metal mesh elements with a desired or predetermined corrugated
configuration suitable for its use as a spacer member, e.g. a
corrugated configuration whereby the mesh element has a cross
section which resembles a square wave.
[0010] However, the process of expanding a metal sheet and/or
cutting the expanded metal sheet to size (i.e. rectangular sheets)
for use as a spacer member results in a sheet metal mesh element
having opposed peripheral side edges which have a jagged shape or
contour; such contour presents a handling hazard since the contour
may effectively act as a sharp cutting edge which may result in
injury to person handling or manipulating the sheet metal mesh.
[0011] Thus, for example, it is known to use such a corrugated mesh
of expanded sheet metal as a spacer member for a plate-type air to
air heat exchanger as described above. However the incorporation of
such sheet metal mesh into a heat exchanger provides an exchanger
wherein jagged edges are exposed on the upstream and downstream
sides of the above mentioned first and second passageways. Such
exposed jagged edges may as mentioned present a safety hazard to a
person manually handling such an exchanger, i.e. if improperly
handled such exchanger may cause hand injury for example.
[0012] Thus it would be advantageous to have available corrugated
expanded sheet metal mesh which avoids or attenuates such jagged
edge contour. It would further be advantageous to have an exchanger
wherein the upstream and downstream edges of a spacer member
comprising a corrugated mesh of expanded sheet metal which avoids
or attenuates such jagged edge contour. It would further be
advantageous to have a method for the fabrication of a spacer
member as well as a plate-type heat exchanger element for a
plate-type air to air heat exchanger comprising a corrugated mesh
of expanded sheet metal which avoids or attenuates such jagged edge
contour.
STATEMENT OF INVENTION
[0013] Thus the present invention in an aspect provides a spacer
member for a plate-type air to air heat exchanger, said spacer
member comprising a corrugated mesh of expanded sheet metal having
an upstream side edge and a downstream side edge
characterized in that said upstream side edge and said downstream
side edge are folded over edges.
[0014] The present invention in another aspect provides a
plate-type heat exchanger element for a plate-type air to air heat
exchanger, said heat exchanger element comprising a heat exchange
partition sheet and a spacer member, said spacer member comprising
a corrugated mesh of expanded sheet metal, said corrugated mesh
having an upstream side edge and a downstream side edge
characterized in that said upstream side edge and said downstream
side edge are folded over edges.
[0015] The present invention in particular provides a plate-type
heat exchanger element for a plate-type air to air heat exchanger,
said heat exchanger element comprising a heat exchange partition
sheet and a spacer member, said spacer member comprising a
corrugated mesh of expanded sheet metal, said corrugated mesh
having an upstream side edge, a downstream side edge and a pair of
opposed wall side edges connecting said upstream side edge to said
downstream side edge,
[0016] characterized in that said upstream side edge and said
downstream side edge are folded over edges
[0017] and
[0018] said heat exchange partition sheet is attached to said
corrugated mesh at each of said wall side edges so as to define an
exchanger air flow barrier element.
[0019] The present invention in a further aspect provides
plate-type air to air heat exchanger, comprising
[0020] a plurality of stacked heat exchange partition sheets, each
partition sheet being spaced apart from an adjacent partition sheet
by respective spacing apart means so as to thereby form a plurality
of first and second passageways for a first air stream and a second
air stream to pass there through, respectively;
[0021] means for sealing two opposing sides of said first
passageways thereby allowing the first air stream to pass there
through in a first direction;
[0022] means for sealing two opposing sides of said second
passageways thereby allowing the second air stream to pass there
through in a second direction
[0023] and
[0024] wherein said spacing apart means for each of said first and
second passageways comprises a corrugated mesh of expanded sheet
metal having an upstream side edge and a downstream side edge
[0025] characterized in that said upstream side edge and said
downstream side edge are folded over edges.
[0026] It is to be understood herein that the expressions `folded
over edge`, `folded over edges` and the like refers to an edge
which, relative to the initial jagged edge, is a (relatively) dull
edge.
[0027] In accordance with the present invention a partition sheet
may be of material having heat conductivity and moisture
permeability; a partition sheet may for example be of paper (i.e.
of heat and moisture permeable paper).
[0028] In accordance with the present invention a corrugated mesh
may be of expanded (sheet) aluminum.
[0029] In accordance with the present invention a plate-type air to
air heat exchanger may take on a quadrilateral configuration and in
particular a rectangular configuration (e.g. the partition sheets
as well as the spacer members may have a rectangular
configuration).
[0030] In accordance with the present invention, a spacer member
may, for example, be fabricated by exploiting any known, desired or
appropriate, sheet metal expansion technique to provide a mesh of
expanded sheet metal (sometimes referred to herein simply as sheet
metal mesh) having opposed jagged or sharp edges; the sheet metal
mesh may, for example, be in the form of a roll thereof or an
elongated sheet thereof. Such initial mesh of expanded sheet metal
may for example be a mesh of expanded aluminum foil.
[0031] An initial mesh of expanded sheet metal may be subjected to
a folding treatment stage at an edge folding station (of any
suitable or desired, configuration) which is able to impart opposed
folded over edges to a sheet metal mesh, i.e. provide opposed
folded edges having a dulled aspect relative to any initial jagged
edges. At such edge folding station, opposed edge margin portions
of the sheet metal mesh are each folded over themselves so as to
form or define a respective folded over edge; each opposed edge
margin portion comprises a longitudinally extending edge portion of
a respective jagged or sharp edge. The edge folding station may if
desired be a manual folding station wherein folding is accomplished
manually or by hand. Preferably however the folding station is a
mechanical edge folding station.
[0032] The edge folding station may, for example, comprise any
suitable means for progressively moving (i.e. feeding) a mesh of
expanded sheet metal through a folding apparatus; it is to be
understood herein that movement of the mesh in an upstream
direction means movement of the mesh through the folding station.
The folding apparatus may, for example, comprise two spaced apart
folding members disposed for folding engagement with a respective
opposed edge margin portion of the sheet metal mesh. In this
manner, opposed edges of the sheet metal mesh may be more or less
simultaneously folded over as the folding members are disposed
directly opposite to each other. Alternatively, the folded over
edges may be obtained by folding over one edge followed by folding
over of the other edge, i.e. the folding members are offset
relative to each other.
[0033] In any event, each folding member may comprise or take the
form of a guide flange having a guide surface which initially
tapers upwardly in the upstream direction, then inwardly over the
metal sheet mesh and finally downwardly towards the metal sheet
mesh until the guide surface is essentially parallel to the opposed
surface of the sheet metal mesh. In other words a folding member
may have a guiding type surface which is able to engage a
respective edge margin portion of the sheet metal mesh so as to
effect a gradual and continuous displacement (i.e. curling over) of
a respective margin portion of the sheet metal mesh upwardly and
eventually over the adjacent portion of the sheet mesh until the
margin portion is folded over the sheet metal mesh as desired.
Preferably, the spacing between the upper parallel portion of the
guide surface and the sheet metal mesh is such as to provide a
permanent crimped edge. The folding members may be considered as
each being one-half of a funnel the purpose of which is to fold
over a respective edge margin portion.
[0034] If desired or necessary the obtained sheet metal mesh with
opposed folded edges may then be fed through the nip of a pair of
opposed compression rollers in order to not only consolidate the
folds but if so desired to reduce the thickness of the sheet metal
mesh.
[0035] If the sheet metal mesh with opposed folded edges is
obtained in the form of a roll or as an elongated sheet, the sheet
metal mesh may as desired or necessary be passed through a cutting
station wherein a guillotine type cutter may, for example cut the
sheet metal mesh, transversely (e.g. perpendicular) to the opposed
folded edges, into smaller desired parallelogram forms (e.g. a
rectangular form such as for example a square) or any other four
sided or quadrilateral type forms as desired or needed. The
obtained sheet metal mesh elements with opposed folded edges will
in any event have opposed major sides which present a generally
flat or planar aspect.
[0036] On the other hand, the edges of the sheet metal mesh
elements formed by the cutting process may give rise to a further
pair of jagged edges as described herein, i.e. give rise to a sheet
metal mesh element with a pair of opposed folded edges and a pair
of opposed jagged edges. These further jagged edges may as desired
or necessary be subjected to a folding process the same as or
analogous to that described above. Alternatively, these jagged
edges may, for example, be covered by the heat transfer partition
sheet as shall be described below.
[0037] An obtained metal sheet mesh element with opposed folded
edges may, for example, be fed, folded edge first, through a
corrugation station so as to provide the sheet metal mesh with
corrugations which extend from one folded edge to the other folded
edge; the folded edges thus being able to take on the role of an
upstream or downstream edge as described herein. The corrugation
station may for example comprise a pair of compression rollers. The
compression rollers may each have a plurality of female and male
members which are able to mate with the corresponding male or
female members of the opposed compression roller. The compression
rollers are configured and disposed so as to be able to impart to
the sheet metal mesh, passing through the nip, defined by
compression rollers, a desired corrugated configuration (e.g. a
square wave like cross sectional shape, a sinusoidal wave like
cross sectional shape, a saw tooth wave like cross sectional shape,
and the like). The obtained corrugated sheet metal mesh may then be
used as a spacer member to form, along with a heat transfer
partition sheet, a plate-type heat exchanger element for a
plate-type air to air heat exchanger.
[0038] A corrugated sheet metal mesh element (i.e. expanded
aluminum foil) with opposed folded edges and opposed jagged edges
may, for example, be of rectangular form, i.e. rectangular when
viewed from above or below. The sheet metal mesh may, for example,
be corrugated such that the jagged side edges are each defined by a
respective marginal edge portion of the sheet metal mesh element
wherein the marginal edge portions more or less reflect the planes
of the initial major sides of the un-corrugated sheet metal mesh.
In this case a square crest of the corrugated sheet metal mesh is
disposed immediately adjacent to each marginal edge portion. The
corrugations of the corrugated sheet metal mesh element may, for
example, when the mesh is viewed in cross section, also have a
rectangular (e.g. square) wave like presentation, i.e. have
rectangular crests and valleys of the same height and depth.
[0039] A rectangular plate type heat exchanger element may, for
example, be fabricated by placing a rectangular (e.g. square)
corrugated sheet metal mesh element (as described immediately
above) onto the surface of a rectangular heat transfer partition
sheet which is sized so that the mesh and partition are able to be
disposed edge to edge fashion. The folded over edges of the sheet
metal mesh and the adjacent edges of the underlying partition sheet
may be more or less coterminous. On the other hand, the partition
sheet may also be sized or dimensioned such that the marginal edge
portions of the partition sheet which are adjacent to the jagged
edges of the sheet metal mesh element remain uncovered by
respective jagged edges of the sheet metal mesh, i.e. the jagged
edges of the sheet metal mesh are inwardly offset with respect to
the adjacent marginal edge portions of the partition sheet so as to
leave these edges of the partition sheet uncovered. The jagged
edges may be sufficiently offset such that the uncovered edge
portions of the underlying partition sheet may be folded over the
jagged edges so as to function as or be part of a side wall sealing
means as shall be discussed below.
[0040] Once the rectangular corrugated sheet metal mesh element is
suitably disposed on top of the underlying partition sheet (e.g. of
paper), a bead of a hot thermoplastic adhesive (e.g. a hot melt
glue or a similar or analogous type thermoplastic adhesive) may,
for example, be applied to the upper surface of each of the above
mentioned sheet metal mesh marginal edge portions in an elongated
longitudinally extending bead extending from one folded over edge
to the other folded over edge. The bead may be applied to the mesh
marginal edges so as to more or less match the height of the
adjacent square crest of the sheet metal mesh. While each of the
adhesive beads is still soft, each of the adjacent uncovered edge
portions of the partition sheet may be folded over the adhesive
bead so as to be fixed thereby to the expanded metal sheet mesh
(e.g. aluminum mesh).
[0041] However, it is to be noted that the width of the uncovered
edge portions of the partition sheet, the height of the adjacent
rectangular crests and the thickness of the adhesive bead may, in
this case, be predetermined such that once the uncovered edge
portions of the partition sheet cover and are fixed to the hot melt
adhesive, the so attached uncovered edge portions (once the
adhesive solidifies) extend at least to a respective rectangular
crest so as to define a side air flow barrier (e.g. a side wall
impermeable to air) which is the same height as the adjacent
rectangular crest. For example, the uncovered edge portions of the
partition sheet, when folded over, may only extend to the top of
the adjacent rectangular crest so as to leave all of the
rectangular crests of the corrugate sheet metal mesh element
uncovered and exposed. On the other hand, an axis perpendicular to
both of the uncovered folded over edges may be considered to be an
air flow axis, i.e. an axis along which air will be free to flow
from one (upstream) folded over edge to the other (downstream)
folded over edge. It is nevertheless also to be understood herein
that if it is desired to provide or define an above described side
air flow barrier any other manner of fixing the uncovered edge
portions of the partition sheet may be utilized keeping in mind the
intended purpose of the barrier; e.g. the partition sheet may be
sized so as to be able extend over all of the crests, i.e. the
partition sheet can be wrapped fully around the sheet metal mesh
leaving the above mentioned air flow axis.
[0042] A rectangular plate type heat exchanger element as described
above may, for example, be used to construct a plate type air heat
exchanger.
[0043] Thus, for example, a cross flow, plate-type air to air heat
exchanger may be formed by stacking a plurality of the above
described rectangular plate type heat exchanger elements one on top
of the other such that the major faces of the exchanger elements
abut each other; i.e. one major face of an exchanger element being
defined by the exposed rectangular crests thereof and the other by
the underlying partition sheet. The rectangular plate type heat
exchanger elements may be stacked such that the partition sheet of
an exchanger element overlying an adjacent like exchanger element
abuts exposed rectangular crests of the corrugated sheet metal mesh
element of the underlying exchanger element. The rectangular plate
type heat exchanger elements may also be stacked such that adjacent
exchanger elements are oriented such that the air flow axis of one
exchanger element is perpendicular to the air flow axis of the
other adjacent exchanger element. In this manner each side wall of
the exchanger will comprise a plurality of alternating air openings
and air flow barrier elements (as alluded to above), so as to
thereby form a plurality of first and second passageways for a
first air stream and a second air stream to pass there through,
respectively.
[0044] As may be surmised each partition sheet is thus spaced apart
from an adjacent partition sheet by an intermediate spacing apart
means defined by a corrugated mesh of expanded sheet metal; as may
also be surmised respective air flow barriers define means for
sealing two opposing sides of the first and second passageways
thereby allowing the first and second air streams to pass there
through in respective first and second directions. As may also be
understood each of the first and second passageways comprises an
upstream folded over edge and a downstream folded over edge as
described herein.
[0045] The elements of a stacked exchanger as described above may
be held in place in any suitable manner; see for example Canadian
patent nos. 2,030,577 and 2,122,392 (the entire contents of these
Canadian patent are incorporated herein by reference). The elements
may for example be held together by any (known) type of casing
frame which allows for air access to the air passageways. For
example, the corners of the exchanger may abut correspondingly
shaped elongated angle elements or members which are suitably fixed
to one another; alternatively, elongated angel elements may be
suitably fixed to top and/or bottom cover plate members which abut
the major face of an adjacent exchanger element; please see for
example U.S. Pat. No. 4,051,898.
[0046] In drawings which illustrate example embodiments of the
various aspects of the present invention:
[0047] FIG. 1 schematically illustrates a corrugated expanded metal
sheet mesh section having rectangular crests and valleys of the
same height and depth but without folded over upstream and
downstream edges, the mesh members being only partially shown;
[0048] FIG. 1a schematically illustrates an enlarged partial top
view of the top of a rectangular crest of the expanded metal sheet
mesh section of FIG. 1 showing a jagged edge of an upstream side
edge;
[0049] FIG. 2 schematically illustrates a stacked exchanger having
partition sheets spaced apart by corrugated expanded metal sheet
mesh sections as shown in FIG. 1, the corrugated expanded metal
sheet mesh sections being shown in outline only;
[0050] FIG. 3a schematically illustrates a corrugated expanded
metal sheet metal section having rectangular crests and valleys of
the same height and depth but with folded over upstream and
downstream edges in accordance with the present invention, the mesh
members being only partially shown;
[0051] FIG. 3b is a photograph of a piece of expanded metal sheet
mesh showing one side edge which is a folded over side edge, the
remaining three side reflecting jagged side edges;
[0052] FIG. 4 shows a cross section through the corrugated expanded
metal sheet mesh section of FIG. 3 along the line 4-4 in FIG.
3a;
[0053] FIG. 5 schematically illustrates a plate-type heat exchanger
element, in accordance with the present invention, for a plate-type
air to air heat exchanger, said heat exchanger element comprising a
spacer member comprising a corrugated expanded sheet metal mesh
section as shown in FIG. 3a, the mesh members being only partially
shown;
[0054] FIG. 6 shows a cross section through the plate-type heat
exchanger element of FIG. 5 along the line 6-6 in FIG. 5;
[0055] FIG. 7 schematically illustrates a stacked exchanger of the
present invention comprising a plurality of plate-type heat
exchanger element as shown in FIG. 5, the corrugated expanded metal
sheet mesh sections being shown in outline only;
[0056] FIG. 8 schematically illustrates an expanded sheet metal
mesh in an initially essentially flat or planar form, the mesh
members being only partially shown, in the process of having
opposed side edges being folded over onto themselves;
[0057] and
[0058] FIGS. 9 and 10 schematically illustrate a number of stage of
the fabrication of the plate-type heat exchanger element of FIG. 5
using the corrugated expanded sheet metal mesh section of FIG.
3a.
[0059] Referring to FIG. 1, this figure illustrates a top
perspective view of a rectangular corrugated sheet metal mesh
element 1; the sheet metal mesh element 1 is an expanded sheet
metal as described herein. The corrugations of the corrugated sheet
metal mesh element 1 take the aspect of rectangular crests (some of
which are generally designated by the reference numeral 3) and
rectangular valleys (some of which are generally designated by the
reference numeral 5) of the same height and depth.
[0060] The sheet metal mesh element 1 has an upstream edge 7 and an
opposed downstream edge 9 as well as two interconnecting side edges
11 and 13; i.e. these upstream and downstream edges 7 and 9 are
intended to be respectively disposed on the upstream and downstream
sides of the first and second passageways of a stacked exchanger
such as shown in FIG. 2. The edges 7, 9, 11 and 13 are not folded
over edges and thus each present a jagged aspect as discussed
herein; FIG. 1a illustrates the jagged nature of these edges, the
jagged edge being generally designated in FIG. 1a by the reference
numeral 15. Reference may also be made to FIG. 3b, which is a photo
of a piece of mesh of expanded sheet metal (i.e. aluminum) showing
by way of example such jagged edges along three sides thereof.
[0061] Referring now to FIG. 2, there is illustrated a plate-type
air to air heat exchanger 17. The exchanger 17 comprises a stack of
heat-and-moisture exchange elements superposed on one another so as
to form a multi-layer cross flow heat-and-moisture exchanger. In
the arrangement as shown, the exchanger has a plurality of first
air passageways (generally designated by the reference numeral 19
for a first air stream. The exchanger also has a plurality of
second air passageways (generally designated by the reference
numeral 21 for a second air stream. A plurality of pairs of opposed
side wall barrier elements (one element of each pair being
generally designated by the reference numeral 23) help define the
first passageways 19 thereby allowing the first air stream to pass
through the first passageways in a first airflow direction
generally designated by the reference numerals 25a and 25b; the
arrow 25a being indicative of airflow into the downstream side of
the first passageway and the arrow 25b being indicative of airflow
from the upstream side of the first passageway. A further plurality
of pairs of opposed side wall barrier elements (one element of each
pair being generally designated by the reference numeral 27) help
define the second passageways 21 thereby allowing the second air
stream to pass through the second passageways in a second air flow
direction generally designated by the reference numeral 29a and
29b; the arrow 29a being indicative of airflow into the downstream
side of the second passageway and the arrow 29b being indicative of
airflow from the upstream side of the second passageway. As may be
appreciated the two air flow directions are in crossing
perpendicular relationship with respect to each.
[0062] Each of the first and second passageways are also defined by
heat exchange partition sheets. The heat exchange partition sheets
are spaced apart by a plurality of rectangular corrugated sheet
metal mesh elements; these sheet metal mesh elements have the
structure as illustrated in FIG. 1. In the illustrated exchanger 17
the jagged edges of the upstream and downstream sides of the
corrugated sheet metal mesh elements extend out of the respective
upstream and downstream sides of the first and second passageways
such that the jagged edges are exposed (not shown) and may inflict
injury to a person handling or manipulating the exchanger 17 if the
exchanger 17 is not carefully handled.
[0063] Referring to FIG. 3a, this figure illustrates a top
perspective view of a rectangular corrugated sheet metal mesh
element 40 in accordance with the present invention; the sheet
metal mesh element 40 is also an expanded sheet metal as described
herein. Referring also to FIG. 4, the corrugations of the
corrugated sheet metal mesh element 40 also take the aspect of
rectangular crests (some of which are generally designated by the
reference numeral 42) and rectangular valleys (some of which are
generally designated by the reference numeral 44) of the same
height and depth.
[0064] The sheet metal mesh element 40 has an upstream edge 46 and
an opposed downstream edge 48 as well as two interconnecting side
edges 50 and 52; i.e. these upstream and downstream edges 46 and 48
are also intended to be respectively disposed on the upstream and
downstream sides of the first and second passageways of a stacked
exchanger such as shown in FIG. 7. The edges 46 and 48 are folded
over edges of metal mesh as contemplated by the present invention;
these folded over edges are each shown as an edge band generally
designated respectively by the reference numerals 58 and 60. The
photo of FIG. 3b illustrates an example folded over edge of a piece
of mesh of expanded sheet metal (i.e. aluminum) showing one folded
edge along one side thereof and jagged edges along the three
remaining sides. The folded over edges 46 and 48 also lend a
reinforced nature to the upstream and downstream side edges of the
corrugated sheet metal mesh element 40, i.e. being thicker than the
rest of the body of the corrugated sheet metal mesh element 40.
[0065] Turning again to FIGS. 3a and 4, the interconnecting edges
50 and 52, on the other hand, are not folded over edges and thus
each present a jagged aspect as discussed herein, i.e. edge 50 and
52 are jagged edges. These jagged edges 50 and 52 are each defined
by a respective marginal edge portion of the sheet metal mesh
element 40; the marginal edge portions are generally designated by
respective reference numerals 62 and 64 (see for example FIG. 4).
The marginal edge portions 62 and 64 more or less reflect the
planes of the initial major sides of the un-corrugated sheet metal
mesh. As may be seen from FIG. 4, a square crest 42 of the
corrugated sheet metal mesh element 40 is disposed immediately
adjacent to each marginal edge portion 62 and 64.
[0066] Referring to FIGS. 5 and 6, these figures illustrates an
example a rectangular plate type heat exchanger element 67
comprising a rectangular (e.g. square) corrugated sheet metal mesh
element 40 (as shown in FIG. 3a) attached along the marginal edge
portions 62 and 64 thereof to a rectangular heat transfer partition
sheet 68 by respective adhesive beads 70 and 72. The beads 70 and
72 are covered by edge portions of the partition sheet 68 which
extend up to the top of respective adjacent rectangular crests 42
so as to leave all of the rectangular crests of the corrugate sheet
metal mesh element uncovered and exposed as well as to define side
air flow barriers (respectively indicated by the reference numerals
76 and 78) which are the same height as the adjacent rectangular
crests 42. The axis designated by the reference numeral 82 is
perpendicular to both of the uncovered folded over edges may be
considered to be an air flow axis, i.e. an axis along which air
will be free to flow from one (upstream) folded over edge to the
other (downstream) folded over edge.
[0067] Referring to now to FIG. 7, there is illustrated a
plate-type air to air heat exchanger 86 in accordance with the
present invention. The exchanger 86 comprises a stack of
heat-and-moisture exchange elements 67 (as illustrated in FIGS. 5
and 6) superposed on one another so as to form a multi-layer cross
flow heat-and-moisture exchanger. In the arrangement as shown, the
exchanger has a plurality of first air passageways (generally
designated by the reference numeral 88 for a first air stream. The
exchanger also has a plurality of second air passageways (generally
designated by the reference numeral 90 for a second air stream. A
plurality of the pairs of opposed side wall barrier elements 76 and
78 (only element 76 is seen) help define the first passageways 88
thereby allowing the first air stream to pass through the first
passageways in a first airflow direction generally designated by
the reference numerals 94a and 94b; the arrow 94a being indicative
of airflow into the downstream side of the first passageway and the
arrow 94b being indicative of airflow from the upstream side of the
first passageway. A further plurality of pairs of opposed side wall
barrier elements 76 and 78 (only element 78 is seen) help define
the second passageways 90 thereby allowing the second air stream to
pass through the second passageways in a second air flow direction
generally designated by the reference numeral 98a and 98b; the
arrow 98a being indicative of airflow into the downstream side of
the second passageway and the arrow 98b being indicative of airflow
from the upstream side of the second passageway. As may be
appreciated the two air flow directions are in crossing
perpendicular relationship with respect to each, i.e. the air flow
axis (element 82 in FIG. 5) of one heat-and-moisture exchange
elements 40 is perpendicular to an adjacent of heat-and-moisture
exchange elements 40.
[0068] Each of the first and second passageways are 88 and 90 also
defined by heat exchange partition sheets (element 68 in FIGS. 5
and 6). The heat exchange partition sheets 68 are, however, spaced
apart by a plurality of rectangular corrugated sheet metal mesh
elements (element 40 in FIG. 3a); these sheet metal mesh elements
thus have the structure as illustrated in FIGS. 3a and 4. In the
illustrated exchanger 86 the upstream and downstream sides of the
corrugated sheet metal mesh elements 40 have folded over edges
(elements 58 and 60 in FIGS. 3a and 5) in accordance with the
present invention.
[0069] Turning to FIG. 8, this figure illustrates an expanded sheet
metal mesh 100 in an initially essentially flat or planar form, in
the process of having opposed side edges designated generally by
respective reference numerals 102 and 104 being folded over onto
themselves at an edge folding station. The folding station
comprises any suitable means (not shown) for progressively moving
(i.e. feeding) the mesh 100 through a folding apparatus or
system.
[0070] The folding apparatus comprises two spaced apart folding
members 106 and 108 fixed in place by any suitable means relative
to the moving mesh 100. As may be seen the folding members 106 and
108 are disposed for folding engagement with edge portions of a
respective opposed edge 102 and 104 of the sheet metal mesh 100. In
this manner, the opposed edges 102 and 104 of the sheet metal mesh
100 may be more or less simultaneously folded over since the
folding members 106 and 108 are disposed directly opposite to each
other.
[0071] Each folding member 106 and 108 takes the form of a guide
flange having a guide surface which initially tapers upwardly in
the upstream direction (indicated by the arrow 110), then inwardly
over the metal sheet mesh and finally downwardly towards the metal
sheet mesh until the guide surface is essentially parallel to the
opposed surface of the sheet metal mesh 100. In other words a
folding member 106 or 108 may have a guiding type surface which is
able to engage a respective edge margin portion of edge 102 or 104
of the sheet metal mesh 100 so as to effect a gradual and
continuous displacement (i.e. curling over) of a respective margin
portion of the sheet metal mesh 100 upwardly and eventually over
the adjacent portion of the sheet metal mesh 100 until the margin
portion is folded over the sheet metal mesh as desired, e.g. to
form edge portion 58 or 60 (see FIG. 3a). The spacing between the
upper parallel portion of the guide surface and the sheet metal
mesh 100 is such as to provide a permanent crimped edge. The
folding members may be considered as each being one-half of a
funnel the purpose of which is to fold over a respective edge
margin portion.
[0072] The fabrication of a rectangular plate type heat exchanger
element (designated by reference numeral 67 in FIG. 5) will now be
discussed by referring to FIGS. 9 and 10 as well as FIGS. 3a, 5 and
6. Referring in particular to FIGS. 9 and 10, a corrugated sheet
metal mesh element 40 (FIG. 3a) is placed onto the surface of a
rectangular heat transfer partition sheet 68 (FIG. 5). As may be
seen heat transfer partition sheet 68 is sized so that the sheet
metal mesh element 40 and partition sheet 68 are able to be
disposed edge to edge fashion. The edges 46 and 48 of the sheet
metal mesh 40 and the adjacent edges of the underlying partition
sheet 68 are more or less coterminous. On the other hand, the
partition sheet 68 is sized or dimensioned such that the marginal
edge portions 110 and 112 of the partition sheet 68 are offset with
respect to the marginal edge portions 62 and 64 of the sheet metal
mesh element 40 such that the marginal edge portions 110 and 112
remain uncovered, i.e. the jagged edges 50 and 52 of the sheet
metal mesh element 40 are inwardly offset with respect to the
adjacent marginal edge portions 110 and 112 of the partition sheet
68. The jagged edges 50 and 52 are sufficiently offset such that
the uncovered edge portions 110 and 112 of the underlying partition
sheet may be folded over the jagged edges 50 and 52 so as to
function as or be part of a side wall sealing means as shall be
discussed below.
[0073] Once the rectangular corrugated sheet metal mesh element 40
is suitably disposed on top of the underlying partition sheet (e.g.
of paper) as discussed above, a bead of a hot thermoplastic
adhesive (e.g. a hot melt glue or a similar or analogous type
thermoplastic adhesive) is applied from an applicator (designated
by the reference numeral 18) to the upper surface of each of the
above mentioned sheet metal mesh marginal edge portions 62 and 64
in an elongated longitudinally extending bead (120 and 122)
extending from folded over edge 46 to the other folded over edge
48. The beads 120 and 122 are applied to the marginal edges 62 and
64 so as to more or less match the height of the adjacent square
crests 42 of the sheet metal mesh element 40. While each of the
adhesive beads 120 and 122 is still soft, each of the adjacent
uncovered edge portions 110 and 112 of the partition sheet 68 may
be folded over a respective adhesive bead 120 and 122 so as to be
fixed thereby to the expanded metal sheet mesh 40 (e.g. aluminum
mesh).
[0074] However, it is to be noted that the width of the uncovered
edge portions 110 and 112 of the partition sheet, the height of the
adjacent rectangular crests and the thickness of the adhesive bead
is such that once the uncovered edge portions 110 and 112 of the
partition sheet 68 cover and are fixed to the hot melt adhesive,
the so attached uncovered edge portions (once the adhesive
solidifies) extend to a respective rectangular crest 42 so as to
define a side air flow barrier 76 and 78 (see FIG. 6) which is the
same height as the adjacent respective rectangular crest 42. Thus
as may be seen form FIGS. 5 and 6 the uncovered edge portions 110
and 112 of the partition sheet, when folded over, only extend to
the top of the adjacent rectangular crest 42 so as to leave all of
the rectangular crests of the corrugate sheet metal mesh element 40
uncovered and exposed.
[0075] A rectangular plate type heat exchanger element as described
above may be used to construct a plate type air heat exchanger also
as described above.
* * * * *