U.S. patent application number 11/948159 was filed with the patent office on 2008-11-06 for thermal energy exchanger.
Invention is credited to John Gietzen.
Application Number | 20080271874 11/948159 |
Document ID | / |
Family ID | 39938744 |
Filed Date | 2008-11-06 |
United States Patent
Application |
20080271874 |
Kind Code |
A1 |
Gietzen; John |
November 6, 2008 |
THERMAL ENERGY EXCHANGER
Abstract
A thermal energy exchanger assembly (100) includes an exchanger
housing (138). The exchanger housing (138) houses a pair of core
support assemblies (174) formed of individual core supports (200).
The core supports (200) are coupled together so as to form
apertures 228. Core tubes (180) are received within the apertures
(228). A fresh airstream (122) is made to flow through the core
tubes (180) while a stale airstream (114) is made to flow between
and around the core tubes (180). In this manner, an exchange of
thermal energy occurs between the fresh airstream (122) and the
stale airstream (114).
Inventors: |
Gietzen; John; (Holland,
MI) |
Correspondence
Address: |
VARNUM, RIDDERING, SCHMIDT & HOWLETT LLP
333 BRIDGE STREET, NW, P.O. BOX 352
GRAND RAPIDS
MI
49501-0352
US
|
Family ID: |
39938744 |
Appl. No.: |
11/948159 |
Filed: |
November 30, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11800287 |
May 4, 2007 |
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11948159 |
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Current U.S.
Class: |
165/54 |
Current CPC
Class: |
F28D 7/1615 20130101;
F28F 9/0221 20130101 |
Class at
Publication: |
165/54 |
International
Class: |
F24H 3/02 20060101
F24H003/02 |
Claims
1. A thermal energy exchanger assembly adapted for use for
exchanging energy between a stale airstream and a fresh airstream,
said exchanger assembly comprising: an exchanger housing; means for
providing an entry of a fresh airstream into said exchanger
housing; means for providing entry of a stale airstream into said
exchanger housing; a pair of core support assemblies, each core
support assembly comprising a series of core supports coupled
together and defining a series of apertures therein; a plurality of
core tubes extending between said pair of core support assemblies
and received within said core support apertures; and said fresh
airstream flows through said core tubes, and said stale airstream
flows between and around said core tubes, so that an exchange of
thermal energy occurs between said fresh airstream and said stale
airstream.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 11/800,287 filed on May 4, 2007.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
REFERENCE TO A MICROFISHE APPENDIX
[0003] Not applicable.
BACKGROUND OF THE INVENTION
[0004] 1. Field of the Invention
[0005] The invention relates to thermal energy exchangers and, more
particularly, to thermal energy exchangers adapted primarily for
use in residential, commercial and industrial interiors for
exchange of energy between stale air and fresh air.
[0006] 2. Background Art
[0007] The concept of employing thermal energy exchangers for
various applications is relatively well known. For example, thermal
energy exchangers are used in industrial facilities for insuring
that interior air does not build up to a dangerous level of
pollutants or toxicity. It is also becoming known to utilize
thermal energy exchangers in residential and general commercial
applications. For example, thermal energy exchangers serve very
useful purposes in restaurant facilities, particularly around
kitchen areas where various types of cooking functions are being
undertaken.
[0008] It is also known to employ thermal energy exchangers in
applications such as vehicles. For example, it is known to employ
vehicle thermal energy exchangers having a series of plastic tubes.
The tubes are arranged in a series of mutually parallel rows, with
a pair of plastic collector plates connected to the ends of the
tubes. However, manufacture of the collector plates in single
pieces can exhibit certain problems. For example, the high
precision collector plates may need to be stamped with a relatively
large number of holes (i.e. 200 to 2000). These holes may be of
relatively small diameter, namely on the order of 1.5 to 5 mm. It
is difficult to undertake such stamping processes, particularly
when it is also necessary to undertake periodic checks for
shrinkage and deformation. Still further, the stamping process must
be undertaken while avoiding the presence of molding/dripping into
the holes. Also, manufacture of each collector plate in a single
piece makes it difficult to automatically insert the ends of the
tubes in the holes of the collector plates.
[0009] To overcome these drawbacks, it is also known to undertake
activities where each collector plate is constructed from a number
of plastic terminal elements. The plastic terminal elements are
overlapped and welded together. Each of the terminal elements
includes a series of semi-circular seats separated from each other
by bonding portions, suitable for being welded to corresponding
bonding portions of a complimentary terminal element. The assembly
procedure for this type of thermal energy exchanger starts from a
first pair of terminal elements, engaging the ends of a first row
of tubes in the semi-circular seats of the terminal elements. A
second pair of terminal elements are then positioned above the
first row of tubes, and the bonded portions of the terminal
elements are then welded together. This operational sequence may be
repeated a number of times, in correspondence to the number of rows
of tubes that form the finished thermal energy exchanger.
[0010] With this process, adjacent terminal elements may be bonded
together by means of welding, ultrasonic or comparable processes.
These processes can cause the bonding portions in reciprocal
contact to melt together. Also, such welding operations are
extremely delicate, and require accurate calibration of the welding
parameters. For example, if too much material is fused, flash which
is formed by the plastic material can enter the ends of the tubes,
thereby causing perforations. In turn, these perforations can
result in heat exchange fluid leakage in the finished thermal
energy exchanger. In contrast, however, if the space between the
abutting surfaces of the bonding portions of the terminal elements
is not completely closed during welding, a hermetic seal between
the ends of the tubes and the collector plate is not achieved.
Accordingly, in this case as well as the prior, the finished
thermal energy exchanger may have heat exchange fluid leaks.
[0011] An attempt to overcome certain of the foregoing problems is
disclosed in Mannoni, et al, U.S. Patent Application Publication
No. U.S. 2002/0157817 A1, published Oct. 31, 2002. For purposes of
description, reference will be made to the reference numerals
utilized in the disclosure of the Mannoni, et al, patent
application publication. Therein, Mannoni, et al, disclose a
plastic thermal energy exchanger 10. The thermal energy exchanger
10 includes a number of tubes 12 forming a heat exchange core. The
tubes 12 can be characterized as being formed of thin plastic
"straws" arranged in a series of mutually parallel rows. The ends
of the tubes are bonded and sealed to a pair of collector plates
14. Two tanks 16 and 18 are then bonded to the respective collector
plates 14. The tank 18 is equipped with openings 20, providing for
the inlet and outlet of heat exchange fluid.
[0012] Each collector plate 14 can be characterized as being formed
by a series of plastic terminal elements 22. Each terminal element
includes a first and second row of semi-circular seats 24 and 26.
The seats 24 and 26 are separated from each other by bonding
portions 28 and 30. Each terminal element 22 is equipped with a
pair of space elements 32. In final assembly, the pair of space
elements 32 will rest against a surface 34 of an identical terminal
element 22. Assembly can be undertaken utilizing single layers.
Each layer can be realized by means of an operational sequence. The
operational sequence includes the following functional steps:
[0013] a. Preparing a first terminal element 22a. [0014] b. Placing
the ends of a row of tubes 12 in the seats 26 of the first terminal
element 22a. [0015] c. Offering up a second terminal element 22b,
such that the ends of the tubes 12 engage with the seats 24 of the
second terminal element 22b. [0016] d. Welding the bonding portions
28 and 30 of the first and second terminal elements 22a and 22b,
respectively, together along the welding plane or surface 34.
[0017] For the Mannoni, et al, assembly, the welding plane or
surface 34 represents or can be characterized as an "ideal" joint
plane, allowing the semi-circular seats 24 and 38 which face each
other to be united together. This assembly results in a formation
of circular seats, with a diameter equal to that of the external
diameter of the ends of the tubes 12.
[0018] Mannoni, et al, then go on to illustrate views of the two
complimentary bonding portions 28, 30 which are to be bonded
together by means of the welding process. Each bonding portion 28
of the terminal element 22a can be characterized as a butt surface
36, set back with respect to the welding plane 34. The volume
between the welding plane 34 and the butt surfaces 36 of the
terminal element 22a can be characterized as Va. Each bonding
portion 30 of the terminal element 22b has a welding portion 38.
The welding portion 38 projects beyond the welding plane 34. The
volume of material of each bonding portion 30 projecting beyond the
welding plane 34 is characterized as Vb. Mannoni, et al, then
further disclose the concept that a "fill ratio" R can be defined
as the ratio between the volumes Va and Vb. Mannoni, et al, then
further describe the concept that the fill ration R would be in the
range, for their embodiment, of 0.8 to 1.3.
[0019] Mannoni, et al, further describe and illustrate a bonding
zone between the bonding portions 28, 30, after completion of
welding. Mannoni, et al, further explain that the fact of having a
fill ratio which is relatively close to unity allows the volume Va
to be filled with material originating from the melting of volume
Vb. Mannoni, et al, characterize this fact as permitting a
substantially ideal bond between the terminal elements 22a and 22b.
Mannoni, et al, also describe the concept that, in particular,
problems of excess molten material occluding the ends of the tubes
that are not completely sealed due to an insufficient amount of
molten material, are avoided. To better describe this concept,
Mannoni, et al, illustrate and describe a situation following a
welding operation with a fill ratio that is considered to be too
high. That is, the fill ratio is in excess of 1.3. In such a case,
the excess molten material will exude laterally from the reciprocal
mating surfaces of the bonding portions, and thus invade the spaces
of the tubes. Such molten material may damage the walls of the
tubes and cause heat exchange fluid leaks.
[0020] In contrast, Mannoni, et al, also describe the concept where
the fill ratio is considered to be too low. That is, the fill ratio
is less than 0.8. In this situation, the material that is welded is
insufficient to fill the space between the butt surfaces of the
bonding portions, thus giving rise to openings that can cause heat
exchange fluid leaks by means of the collector plate.
[0021] As with Mannoni, et al, and other heat exchange assembly
processes for plastic tube exchangers, full plates are utilized,
with holes required for the insertion of the tubes through the
holes. The holes are then sealed with either a heated wire, glue or
the like. This is considered to be an extremely slow and labor
intensive process. Accordingly, it would be advantageous if a
design utilized for the end plate would be made of preformed
inserts, allow for the tubes to be quickly assembled and then
sealed with, for example, compression processes.
[0022] Various other types of systems employing heat exchanging
concepts have been developed and are known in the industry. For
example, Stark, U.S. Pat. No. 6,182,747 issued Feb. 6, 2001
discloses an air-to-air heat exchanging system utilizing a first
air stream and a second air stream. The system includes at least
two air-to-air thermal energy exchangers, with each having heat
conducting walls, secured to a frame. The system can be
characterized as having crossflow thermal energy exchangers with a
series of parallel channels alternately blocked and enclosed within
a housing. In this manner, one airstream is forced to be directed
through the exhaust air channels, and a second airstream is
directed through the supply air channels. This occurs in a
substantially crossflow arrangement, and can further be
characterized as a plate-type thermal energy exchanger system. In
addition to the foregoing, the Stark system includes arrangement of
a number of the thermal energy exchanger units in a side-by-side
configuration, with a manifold for purposes of dispersing and
gathering the related airstreams to a plenum chamber, so as to
reduce the size of the system and the energy requirements for
operating the system for conditioning a large volume of air.
[0023] Stark further describes what he considers to be prior art to
his own thermal energy exchanger system. For example, Stark
describes the concept that a number of different devices that
exchange heat between airstreams are relatively well known, whereby
stale air is exhausted from a building source as an energy source
for heating or cooling incoming outside air.
[0024] Stark further describes the concept that there currently
exists a number of crossflow plate-type air-to-air thermal energy
exchangers. These known devices can be constructed of plastic or
metal for heat exchange or alternatively, can be constructed of a
homogenous material (such as paper) for a latent energy exchange.
In the prior art thermal energy exchangers, Stark describes the
concept that a large space is generally required, for purposes of
housing the large plate crossflow thermal energy exchangers. As
plates of a plate thermal energy exchanger increase in size, and
for a given efficiency, the space in between the plates must
increase in distance. Correspondingly, such increase in plate
spacing results in a significant increase in the entirety of the
volume of the heat exchanging apparatus.
[0025] Stark further explains that volumetric efficiency quantifies
as the required equipment volume in a "per unit of capacity" at a
given performance level. In plate-type crossflow air-to-air thermal
energy exchangers, and for purposes of increase in the volume
efficiency and economy of the unit, the smallest possible plate
size should preferably be used. However, crossflow thermal energy
exchangers with smaller plates generally require additional length
(i.e., additional plates) for handling air volumes equal to those
of units having larger plates. However, increase in the plate size
will require a relatively larger installation space, which may then
limit the performance of the thermal energy exchanger. Also, when
using crossflow plate-type air-to-air thermal energy exchangers
with smaller plates, the length, or number of plates, typically
exceeds the allowable dimensions or number of plates.
[0026] In the Stark system, certain of the disadvantages associated
with systems known prior to Stark are allegedly obviated. More
specifically, Stark describes the concept of providing a plate-type
crossbow air-to-air thermal energy exchanger with a series of
plates, while maintaining a seal between the intake channel and
exhaust channels. Stark also describes the concept that the thermal
energy exchanger facilitates installation in a system which
utilizes a relatively small number of units, so as to reduce the
size required for installation, while correspondingly providing a
relatively efficient operating and economical system for recovering
heat in buildings, such as homes and offices.
[0027] In summary, the apparatus described in Stark can be utilized
as a thermal energy exchanger, where intake air is heated or cooled
in a plate thermal energy exchanger, using the heat energy in the
exhaust air. The exhaust air flow travels through the exhaust
channel, of which at least one wall of the channel represents the
wall separating the intake channel from the exhaust channel. It is
through this wall that the heat exchange process occurs.
[0028] A series of conducting walls are arranged face to face, and
then also arranged in a side-by-side configuration, in rows so as
to complete the necessary amount of heat exchange space. The number
of intake and exhaust channels is determined by the amount of
plates provided, which is variable with respect to the
installation. Stark describes the concept that a square shape for
the thermal energy exchanger is preferably positioned on a point of
the square, so that a diagonal running from one corner of the
square to its opposite corner is generally vertical when the unit
is installed.
[0029] The thermal energy exchanger plates are disclosed as being
spaced apart by a series of corrugations extending between the
walls and in thermal contact with each of the walls. The
corrugations serve the dual purpose of enhancing heat transfer
between the walls, and also providing flow paths for the airstream
to seal the intake channels from the exhaust channels. Stark
describes the concept of the preferred arrangement as a crossflow,
where the air path and intake channels are arranged at right angles
to the air path and exhaust channels. In this manner, the flow path
through the heat conducting walls is defined so that the intake air
flow is substantially in a crossflow arrangement from the exhaust
air flow. Stark also discloses the concept that the Stark
configuration may use two manifolds, consisting of entrance and
exit ports for the intake airstream and entrance and exit ports for
the exhaust airstream. The flow pattern through the apparatus is
considered to be a function of how the manifolds are baffled in
relation to one another. The flow pattern may be arranged for
either crossflow or parallel flow.
[0030] Thunberg, U.S. Pat. No. 4,391,321 issued Jul. 5, 1983
discloses another thermal energy exchanger for use in ventilating
interior structures. The thermal energy exchanger is utilized in
combination with a two duct system, for bringing relatively cold
outside air into an enclosure, while exhausting relatively warm
room air from the enclosure. The thermal energy exchanger is
positioned so as to recover heat from the exhaust air into the
incoming cold fresh air. Specifically, Thunberg discloses the
concept of employing a valving system which switches the incoming
cold air with the warm exhaust air in the flow paths of the thermal
energy exchanger. Thunberg describes the concept that this valving
configuration allegedly solves the problem of moisture from the
exhaust air condensing on the walls of the ducting system for the
exhaust air.
[0031] Martin, et. al., U.S. Pat. No. 4,336,748 issued Jun. 29,
1982 discloses an exchanger for exchanging a first fluid with a
second fluid, in varying proportions. A first duct carries the
first fluid, while a second duct carries the second fluid. A
transfer chamber is connected to both ducts through which some or
all of the second fluid is able to be transferred back into the
first duct. A variable control system is provided in the form of
first and second damper blades in the chamber which can be swung
together, thus dividing the chamber and preventing transfer. The
blades can correspondingly be swung apart so as to provide for
varying proportions of the transfer. The chamber also has an inlet
means for inlet of the first fluid, and outlet means for discharges
of the second fluid.
[0032] Goldsmith, U.S. Pat. No. 3,934,798 discloses a heat
exchanging system for use with a forced draft home heating system.
Air is directed from a return register to the return plenum through
a thermal energy exchanger interposed in the line of the flue. The
thermal energy exchanger includes an enlarged casing extending
between tapered collars, and enclosing heat exchange tubes having
approximately the same cross sectional area as the flue.
[0033] George, U.S. Pat. No. 4,334,577 issued Jun. 15, 1982
discloses a ventilation system for a livestock house. The system
includes a thermal energy exchanger whereby, prior to entering the
thermal energy exchanger, warm moist air from the interior passes
through a filter device that removes particulates. In this manner,
the particulates do not combine with condensation in the thermal
energy exchanger, so as to block the thermal energy exchanger.
Fresh air, received from the outside, and after being warmed in the
thermal energy exchanger, passes into an elongated distribution
plenum located slightly below the ceiling of the livestock house.
This plenum contains apertures which direct the fresh air
horizontally into the housing area. The upper surface of the plenum
is located directly below an elongated opening in the ceiling.
Along each side of the opening, baffles are hinged to the ceiling.
The baffles extend obliquely outwardly and downwardly, and contact
the upper surface of the plenum at their lowermost edges. With this
configuration, warm moist air from the building is prevented from
escaping through the opening and into an attic area above the
ceiling. However, when exhaust fans are energized to exhaust air
from the living area, the withdrawn air is replaced by air from the
attic. This air is passed into the living area by lifting the
baffles and flowing outwardly over the horizontal upper surface of
the plenum.
[0034] With an appropriate accommodation of tube designs and core
plate designs, assembly speed can not only be facilitated, but
other problems can also be overcome. For example, it would be
advantageous to have the capability of eliminating the need for
defrosting units in cold weather. If this problem could be
eliminated, it would greatly reduce the overall cost of plastic
tube exchanges, compared to other types of thermal energy
exchangers on the market. Elimination of the defrost cycle and
related parts would allow for the use of all plastic housing and
axial fan components. Accordingly, an "all plastic" thermal energy
exchanger or "heat recovery ventilator" ("HRV") could be made
available. Such a thermal energy exchanger would have numerous
advantages. For example, one of the by-products of air-to-air heat
exchange is condensation on the inside of housing and tubes. With
metal housings, units are subjected to rust, eventually resulting
in the mixing of the airstreams and ultimate failure of the HRV
unit. With an all plastic assembly, the longevity of the HRV or
thermal energy exchanger is increased, due to the elimination of
components subject to rust.
[0035] Another aspect of air-to-air thermal energy exchanger
assemblies is that the longer the air can stay within the core, the
"more efficient" the actual exchange will function. In this regard,
it would be advantageous to have some type of assembly or design
which would improve exchange rates between the two airstreams.
Another aspect of providing for more efficient exchange of thermal
energy relates to surface areas of surfaces which separate fresh
airstreams from stale airstreams. That is, the greater the surface
area of the material which separates the stale airstream from the
fresh airstream, the higher will be the flow rate of thermal energy
between the airstreams.
[0036] In addition, it would also be advantageous to undertake tube
designs which will improve relative cleanliness. Known plate core
designs accumulate dirt and dust particles, which eventually plug
up the core and reduce exchange efficiency and air flow. Such known
thermal energy exchangers are then relatively difficult to clean,
because such cleaning requires the disassembly of the unit
periodically so as to maintain efficiency. In this regard, it would
be advantageous to utilize a tube design which reduces the
frequency of necessary cleaning, and also facilitates cleaning when
required.
[0037] In accordance with all the foregoing, it would be
advantageous to utilize a core end plate and tube design which
facilitates assembly, runs efficiently, and is of a relatively low
cost. In this regard, it would be advantageous for such a thermal
energy exchanger to have relatively few moving parts, and not be
susceptible to wear, such as rust processes.
[0038] In accordance with the foregoing, it is advantageous to
provide for a thermal energy exchanger meeting these advantages. In
this regard, and with reference to the core, a thin wall plastic
tube may utilize "film heat transfer" technology, so as to pass
heat from one airstream to another, without mixing the air at a
rate comparable to that of aluminum. Such a tube design has
advantages over other plastic cores on the market, because it
provides for a greater surface area than current plate technology.
Also, due to the internal diameter of the tube, it will reject
"freeze-up" in cold weather, which require defrosting cycles.
[0039] More specifically, with the use of plastic tubes having
relatively thin walls, the internal diameter of each tube is
relatively larger than would exist with tubes having relatively
thicker walls. Still further, if the tubes can be supported and
constructed so as to provide for additional and larger spaces
between and around the tubes, freeze-up can again be significantly
reduced. This feature can result in financial savings not only in
that fewer or no defrosting cycles are required, but also that the
use of a fan may not be required whatsoever.
[0040] With respect to the end plates, it is advantageous to
utilize a design where the end plate is made up of preformed
inserts, allowing for the tubes to be quickly assembled and sealed
with compression. Such a design will work with current plastic
tubes, and with enthalpic tubes known to be utilized for energy
recovery ventilators, as well as metal tubes such as copper or
aluminum without design changes to the overall unit.
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] An illustrative embodiment of the invention will now be
described with respect to the drawings, in which:
[0042] FIG. 1 is a partially perspective and partially schematic
diagram of a thermal energy exchanger in accordance with the
invention, as the exchanger may be utilized within an example
building environment;
[0043] thermal energy exchanger
[0044] FIG. 2 is a perspective view of the thermal energy exchanger
in accordance with the invention, showing the relative
configuration of the housing;
[0045] FIG. 3 is a perspective view of one half of the housing of
the thermal energy exchanger shown in FIG. 2;
[0046] FIG. 4 is a perspective view of the housing half illustrated
in FIG. 3, and further showing a pair of core support assemblies
(without tubes) and their relative positioning within the housing
half;
[0047] FIG. 5 is a perspective and partially exploded view of the
thermal energy exchanger in accordance with the invention, showing
one of the housing halves and the pair of core support assemblies
as illustrated in FIG. 4, but further showing the other housing
half in a partially exploded view and also showing upper and lower
frame portions which are coupled to the core support assemblies
(without tubes) so as to form the core plates;
[0048] FIG. 6 is a perspective and exploded view of the thermal
energy exchanger in accordance with the invention, showing the
relative positioning of an air filter which may be used in an
optional manner with the thermal energy exchanger in accordance
with the invention, and further showing means for securing the air
filter within the thermal energy exchanger;
[0049] FIG. 7 is a perspective and partially exploded view similar
to FIG. 6, but showing the thermal energy exchanger rotated
approximately 45.degree. relative to the perspective view of FIG.
6;
[0050] FIG. 8 is a perspective and partially exploded view in the
form of a close-up view showing the positioning of the air filter
relative to the core plate structure;
[0051] FIG. 9 is a perspective and exploded view of a portion of
the thermal energy exchanger in accordance with the invention,
showing the relative positioning of an air filter and also showing
the core plate structure with a partial set of core tubes connected
thereto;
[0052] FIG. 10 is a perspective and exploded view of a portion of
the thermal energy exchanger in accordance with the invention,
again showing relative positioning of the air filter and other
components of the thermal energy exchanger;
[0053] FIG. 11 is a perspective view of a portion of the thermal
energy exchanger in accordance with the invention, showing the
relative location of a drain aperture;
[0054] FIG. 12 is a perspective view similar to FIG. 11, but
showing a drain aperture in a close-up configuration;
[0055] FIG. 13 is a perspective view of a portion of the thermal
energy exchanger in accordance with the invention, showing the
exterior location of one of the drain plugs of the exchanger;
[0056] FIG. 14 is a perspective view of a portion of the thermal
energy exchanger in accordance with the invention, showing a
relatively close-up view of the connecting flanges on both of the
housing halves for purposes of connecting the same together;
[0057] FIG. 15 is a perspective view of a portion of the thermal
energy exchanger in accordance with the invention, showing another
view of the connecting flanges and their relative position with
respect to one of the drain plugs;
[0058] FIG. 16 is a perspective view showing one of the core plates
and the support brackets for the air filter;
[0059] FIG. 17 is a sectional view of a portion of a core plate and
core tubes coupled thereto, with the section taken through one of
the threaded support rods;
[0060] FIG. 18 is a sectional view similar to FIG. 17, but with the
section taken across the core tubes;
[0061] FIG. 19 is a sectional view partially showing the opposing
core plates and the core tubes extending therebetween, and further
shows threaded rods passing through the core supports, so as to
assist in compression of the interlocking core supports and the
compression fit of core tubes with the core supports;
[0062] FIG. 20 is a perspective, partially exploded and sectional
view showing the relative positioning of various components of one
of the core plates and the housing halves;
[0063] FIG. 21 is a partial, perspective view of one of the core
tubes of the thermal energy exchanger in accordance with the
invention, with FIG. 21 being partially schematic in that the
drawing illustrates the exchange of thermal energy with respect to
airstreams passing through and around the tubes;
[0064] FIG. 22 is a perspective view of one embodiment of one of
the core supports of the core plate assemblies of the thermal
energy exchanger in accordance with the invention;
[0065] FIG. 23 is a perspective view of a portion of one of the
core support assemblies formed utilizing a series of the core
supports shown in FIG. 22;
[0066] FIG. 24 is a perspective view of one of a second embodiment
of core supports which may be utilized with the thermal energy
exchanger in accordance with the invention;
[0067] FIG. 25 is a perspective and enlarged view of one end of the
core support shown in FIG. 24;
[0068] FIG. 26 is a perspective and enlarged view of the one end of
the core support illustrated in FIG. 25, but with the core support
of FIG. 26 rotated 90.degree. relative to the view in FIG. 25;
[0069] FIG. 27 is a perspective view illustrating the coupling
together of three of the core supports illustrated in FIGS. 24, 25
and 26;
[0070] FIG. 28 is a perspective and enlarged view of one end of the
core supports shown coupled together in FIG. 27, and showing
relatively greater detail with respect to how the core supports are
interlocked together; and
[0071] FIG. 29 is a perspective and enlarged view of a portion of
the interconnected core supports illustrated in FIG. 28.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0072] The principles of the invention are disclosed, by way of
example, within a thermal energy exchanger assembly 100 as
illustrated in FIGS. 1-29. Assembly 100 in accordance with the
invention provides significant advantages over the prior art. For
example, with the tube designs and core plate designs in accordance
with certain aspects of the invention, assembly speed can be
facilitated. Further, with the use of plastic elements for the
thermal energy exchanger assembly 100, the longevity of the thermal
energy exchanger is relatively increased, due to the elimination of
components which are subjected to rust or the like. Also, the
energy exchanger assembly 100 is adapted to operate without
requiring any internal moving parts. For exchanger assemblies
requiring moving parts (such as internal fans or the like), it is
common for such parts to be metal. Such additional metal parts are
clearly subject to rust. In accordance with one aspect of thermal
energy exchanger assemblies in accordance with the invention, the
internal components of the energy exchanger assembly are
essentially "passive." If fans or other components are desired to
be used to increase the airflow, such fan units or the like may be
positioned exterior to the exchanger assembly. With respect to the
plastic elements of the energy exchanger assembly 100, core tubes
180 (FIG. 21) as described subsequently herein may be manufactured
of polypropylene. Still further, thermal energy exchanger
assemblies in accordance with the invention provide for relatively
greater efficiency, in that exchange rates are improved between the
airstreams flowing within the exchanger assembly. For example, and
in accordance with certain aspects of the invention, the core tubes
180 may have relatively thin walls, in view of their manufacture
from plastic materials. These relatively thinner walls improve
thermal energy transfer. In addition, and as made apparent from
subsequent description herein, the thermal energy exchanger
assembly 100 in accordance with other aspects of the invention may
have a core assembly which provides for substantially more surface
area for thermal energy transfer between airstreams.
[0073] Still further, some known tubular and end plate designs have
a tendency to accumulate dirt and dust particles. The dirt and dust
can eventually plug up a thermal energy exchanger core, and reduce
exchange efficiency and air flow. Further, thermal energy exchanger
assemblies having these properties are often difficult to clean,
because such cleaning typically requires the disassembly of the
unit periodically, so as to maintain efficiency. The thermal energy
exchanger assemblies in accordance with certain aspects of the
invention utilize designs which may reduce the frequency of
requisite cleaning, and also facilitate the cleaning process
itself. In this regard, the thermal energy exchanger assembly 100
in accordance with these certain aspects of the invention may
include the use of air filters for reducing the amount of dirt and
dust which would otherwise typically collect around and in
components of the exchanger assembly.
[0074] In accordance with all of the foregoing, thermal energy
exchanger assemblies in accordance with certain aspects of the
invention are advantageous in that they have relatively few moving
parts, and are relatively less susceptible to wear, including rust
processes. However, if desired, the structure and function of
thermal energy exchangers in accordance with the invention do not
preclude the use of some moving parts, such as a fan or the like
for facilitating air movement.
[0075] Still further, and again in accordance with certain aspects
of the invention, thermal energy exchanger assemblies in accordance
with these aspects of the invention may employ relatively thin wall
plastic tubes, utilizing "film heat transfer" technology. Such
technology provides for passing thermal energy from one airstream
to another, without mixing the air at a rate comparable to exchange
components comprised of various metals, such as aluminum. Also, as
a result of the internal diameter of the tubes in accordance with
certain aspects of the invention, they will tend to reject "freeze
up" in cold weather, which may otherwise require defrosting cycles.
Still further, and in accordance with other aspects of the
invention, core support assemblies utilized in thermal energy
exchanger assemblies in accordance with these aspects of the
invention advantageously utilize a design where the core support
assemblies are made of pre-formed inserts, allowing for tubes to be
relatively quickly assembled into the core plates and sealed with
compression. Still further, core plate designs in accordance with
certain aspects of the invention will function with current plastic
tubes, as well as enthalpic tubes known to be utilized for energy
recovery ventilators. In addition, if desired, core plate designs
in accordance with these aspects of the invention will also
function with metal tubes, such as copper or aluminum, without
requiring design changes to overall exchanger units.
[0076] Turning specifically to the drawings, FIG. 1 is a partially
schematic and partially diagrammatic diagram of the thermal energy
exchanger assembly 100 in accordance with the invention, as it may
be utilized within a building environment 102. The building
environment 102 may be an industrial, commercial or residential
structure. Also, as earlier described, thermal energy exchanger
assemblies in accordance with the invention may be utilized in
other environments, such as vehicles. The thermal energy exchanger
assembly 100 may be located within a structure 104 associated with
the building environment 102. The structure 104 may be constructed
in a manner so that it is somewhat separate from the interior 106
of the industrial, commercial or residential environment being
serviced by the thermal energy exchanger assembly 100. Again, it
should be emphasized that FIG. 1 is essentially a schematic and
diagrammatic illustration, and does not represent particular
components which form the basic novel concepts of the
invention.
[0077] The thermal energy exchanger assembly 100 itself is
essentially enclosed within an external housing 108, which may be
in the form of any conventional structure. The external housing 108
houses the principal components of the exchanger assembly 100 where
the thermal energy exchange between airstreams representing stale
air and fresh air actually occurs. The external housing 108 and
associated components therein (described in subsequent paragraphs
herein) are structurally and functionally connected to elements
which can be characterized as forming a central ventilation system
110. The central ventilation system 110 provides means for guiding
(and, to some extent, forcing) airstreams comprising fresh air and
stale air through the external housing 108 of the thermal energy
exchanger assembly 100. It should be emphasized that numerous
configurations of ventilation systems may be utilized in
substitution of the central ventilation system 110, without
departing from the principal spirit and novel concepts of the
invention.
[0078] Continuing to refer to FIG. 1, the central ventilation
system 110 includes an incoming stale air plenum 112. The plenum
112 may be coupled to the building interior 106 and open to stale
air duct work which provides a series of stale air pathways around
the interior 106. This stale air duct work may be open to the
interior 106 through a series of ventilator screens (not shown) so
as to provide for common stale air pathways throughout the interior
106. Although often not necessary, and depending upon the type and
size of the interior 106, ventilation fans (not shown) may be
utilized within the interior 106 or stale air duct work for
purposes of facilitating air flow through the duct work and the
incoming stale air plenum 112. In any event, the central
ventilation system 110 is structured so that a stale airstream 114
(which is shown as a series of "dotted line" arrows in FIG. 1) is
expelled from the interior 106 through the incoming stale air
plenum 112.
[0079] As further shown diagrammatically in FIG. 1, the stale
airstream 114, consisting of stale air which is often of relatively
high or low temperatures (depending upon geographical locations and
the particular seasons of the year), will flow through the interior
of the exterior housing 108 of the thermal energy exchanger 100.
The stale airstream 114 will then be expelled into and flow through
an outgoing stale air plenum 116. At a terminating end of the
outgoing stale air plenum 116 may be an outgoing stale air vent
118. The vent 118 may be open to an outside environment, and
utilized to expel the stale airstream 114 which has flowed through
the thermal energy exchanger assembly 100. However, as will be made
readily apparent from subsequent description herein, before the
stale airstream 114 is expelled from the exterior housing 108 of
the thermal energy exchanger assembly 100, an energy transfer will
have occurred between the stale airstream 114 and a fresh airstream
122 described in subsequent paragraphs herein.
[0080] In addition to the stale airstream 114, the fresh airstream
122 is also provided for flow through the thermal energy exchanger
assembly 100. The fresh airstream 122 is diagrammatically
illustrated in FIG. 1 as a series of arrows in solid line format.
Again referring to FIG. 1, the fresh airstream 122 can be formed
from fresh air outside of the building environment 102. The fresh
airstream 122 can be brought into the interior 106 through an
incoming fresh air vent 124, with the fresh air vent 124 openly
connected to an incoming fresh air plenum 126. For purposes of
forming the fresh airstream 122, and bringing fresh outside air
into the building environment 102 and interior 106, furnace fans
(not shown) or other types of fan mechanisms may be employed. Such
fan configurations are well known in the HVAC art. However, in
accordance with certain aspects of the invention, it is believed
that the use of core tubes and other components consisting of
plastic materials, along with the wall designs of the plastic
tubes, may be such that fans or other active components are
unnecessary for providing requisite airflow of the airstreams 114,
122 through the thermal energy exchanger assembly 100. That is, the
thermal energy exchanger assembly 100 may have a structure and
design such that it is a completely "passive" thermal energy
exchanger, without requiring any energy driven or other moving
parts.
[0081] After the fresh airstream 122 is brought into the building
environment 102 through the incoming fresh air vent 124, the fresh
airstream 122 flows through the incoming fresh air plenum 126 and
into the exterior housing 108 of the thermal energy exchanger
assembly 100. The thermal energy exchange function and the specific
flow of the fresh airstream 122 through the thermal energy
exchanger assembly 100 will be described in greater detail in
subsequent paragraphs and with respect to subsequent illustrations
herein.
[0082] After the fresh airstream 122 has flowed through the thermal
energy exchanger assembly 100 (and warmed or cooled during the
energy exchange process), the airstream 122 will then flow
outwardly from the thermal energy exchanger assembly 100 into an
outgoing fresh air plenum 128. The outgoing fresh air plenum 128
may be connected, as illustrated in FIG. 1, to fresh air duct work
130. The duct work 130 may provide for common pathways and may be
openly connected through ventilation screens (such as the
ventilation screen 120 illustrated in FIG. 1) to the interior 106.
With this central ventilation system 110, and through the use of
the thermal energy exchanger assembly 100, fresh outside air is
brought into the interior 106, while a substantially equal amount
of stale air is exhausted through the ventilation system 110 to the
outside. Further, as described in subsequent paragraphs herein, the
incoming fresh air stream 122 may be filtered, before flowing
through the core structure (described in subsequent paragraphs) of
the thermal energy exchanger assembly 100. Such a filtering
configuration is described in subsequent paragraphs herein and
illustrated in the drawings. Within the housing 108 of the thermal
energy exchanger assembly 100, the stale airstream 114 flows across
what could be characterized as the "cross-flow" exchanger assembly
100, and may then transfer its heat (or, if operating in the summer
or geographical area having a continuously warm climate, transfer
coolness) to the fresh airstream 122. The fresh airstream 122
passes through the tubes 180 and is then distributed in a
preferably even manner throughout the interior 106. This
distribution can occur through the existing duct work 130 already
employed for a conventional HVAC system. In accordance with all of
the foregoing, stale and polluted air is expelled to the outside
from the interior 106.
[0083] The general structure and configuration of the thermal
energy exchanger assembly 100 will now be described, primarily with
respect to FIGS. 2-20. First, FIG. 2 is a perspective view of the
exterior of the thermal energy exchanger assembly 100. As
illustrated in FIG. 2, the thermal energy exchanger assembly 100
includes an exchanger housing 138. With respect to the relationship
between the exchanger housing 138 and components illustrated in
FIG. 1, the exchanger housing 138 (and the internal components of
the thermal energy exchanger assembly 100) are housed within the
exterior housing 108. As further shown in FIG. 2, the exchanger
housing 138 comprises a first housing half 140 and a corresponding
second housing half 142. The references to "first" and "second" are
for convenience only, and do not necessarily represent any
particular spatial configuration requisite for the exchanger
assembly 100. The housing halves 140, 142 may be manufactured by
injection molding or similar plastic molding or forming processes.
FIGS. 3 and 4 illustrate the structure of the second housing half
142 in a stand alone configuration. FIG. 4 also illustrates the
second housing half 142 with a pair of opposing core support
assemblies which will be described in subsequent paragraphs
herein.
[0084] The first housing half 140 and the second housing half 142
may be connected together in any suitable manner. For example, the
housing halves 140, 142 may include fasteners 144 (shown primarily
in FIGS. 2, 8, 10, 11, 12, 13) which appropriately connect together
the housing halves 140, 142. Such fasteners 144 may be in the form
of bolts, clips or similar connecting elements. For example, in
certain of the drawings of FIGS. 2-20, the fasteners 144 are shown
as clips 143, while others of the drawings show the fasteners 144
as relatively small bolts 145.
[0085] As further shown, for example, in FIG. 5, the first and
second housings 140, 142, respectively, form an incoming fresh air
duct 146 having a cylindrical configuration. The incoming fresh air
duct 146 may preferably be coupled to the incoming fresh air plenum
126 previously described with respect to FIG. 1. Accordingly, the
duct 146 is utilized to bring fresh air into the exchanger assembly
100. As further shown in FIG. 5, the incoming fresh air duct 146
may be constructed of a pair of substantially equally formed duct
arcs comprising a first duct arc 154 and a second duct arc 156.
[0086] In addition to the incoming fresh air duct 146, the thermal
energy exchanger assembly 100 also includes, as shown on the same
side of the housing 108, an incoming stale air duct 148. The
incoming stale air duct 148, like the fresh air duct 146, consists
of a first duct arc 154 and a second duct arc 156. The incoming
stale air duct 148 is adapted to be coupled, in any suitable
manner, to the incoming stale air plenum 112, previously described
with respect to FIG. 1. In addition to the ducts 146 and 148, a
pair of additional ducts 150 and 152 are located on the end of the
housing 108 opposing the end on which the ducts 146 and 148 are
located. Duct 150 can be characterized as an outgoing fresh air
duct 150. The outgoing fresh air duct 150 is adapted to be coupled,
in any suitable manner, to the outgoing fresh air plenum 128,
previously described with respect to FIG. 1. As with the ducts 146,
148, the duct 150 is formed with a first duct arc 154 and a second
duct arc 156.
[0087] The duct 152, which is only partially shown in FIG. 5, can
be characterized as an outgoing stale air duct 152. The outgoing
stale air duct 152 is adapted to be coupled, in any suitable
manner, to the outgoing stale air plenum 116. In FIG. 5, only the
first duct arc 154 of the outgoing stale air duct 152 is
illustrated. Still further, and again with reference to FIG. 5,
second housing half 142 of the housing 138 can be fitted with a
drain 158. The drain 158 will be located in an area where it may be
enabled to drain water which has formed as condensed moisture as a
result of heat being removed from the stale airstream 114 as the
same passes through the exchanger assembly 100. Preferably, and as
shown in various of the drawings, two drains 158 are provided with
the exchanger assembly 100. More specifically, the drains 158 are
illustrated in FIGS. 5, 6, 13, 15. The drains 158 are open to the
interior of the exchanger housing 138 between core plates 160
through a pair of drain apertures 159. The drain apertures 159 are
illustrated in FIGS. 11 and 12.
[0088] As further shown in FIGS. 4-10 and 16-20, the thermal energy
exchanger assembly 100 also includes a pair of core plates 160. The
core plates 160 are identified, for example, in FIGS. 4 and 5 as
comprising a first core plate 162 and an opposing second core plate
164. The core plates 160 are also illustrated (or partially
illustrated) in FIGS. 6-10, 19 and 20. The components of the core
plates 160 and the general structure and functions thereof form the
basis for a number of principal concepts of the invention.
[0089] However, before describing the core plates 160 and
associated components in detail, other elements of the thermal
energy exchanger assembly 100 will be described. More specifically,
the immediately following paragraphs describe components associated
with an air filter assembly, connector components for the exchanger
housing 138 (FIG. 6) and elements for mounting the exchanger
assembly 100 to other structures.
[0090] Reference will now be made to elements of the energy
exchanger assembly 100 as shown in FIGS. 2, 6-10, 13 and 16. More
specifically, the exchanger housing 138 can be mounted to
components separate from the exchanger assembly 100 through the use
of one or more housing connector brackets 132. These brackets are
primarily shown for example, in FIGS. 2, 6 and 7. The housing
connector brackets 132 can have a substantially rectangular
configuration, with an elongated length. The brackets 132 can be
connected to the exchanger housing 138 through the use of bolts 133
(FIGS. 6, 7) extending through appropriate apertures 134 and
secured to the exchanger housing 138 in any suitable manner.
Correspondingly, the housing connector brackets 132 may also
include additional apertures 135 through which screws or other
connecting means (not shown) may be secured to the housing
connector brackets 132 and to other structural elements, such as
the inner sides of the external housing 108 previously described
and illustrated in FIG. 1. It should be emphasized that the use of
the housing connecting brackets 132 represent only an example means
for appropriately securing and positioning the thermal energy
exchanger assembly 100 to various structures.
[0091] As earlier described, the exchanger housing 138 actually
comprises a pair of housing halves. These housing halves are
defined and illustrated as first housing half 140 and second
housing half 142. As also previously described, fasteners 144 can
be utilized to securely couple together the housing halves 140,
142. Still further, it was previously described that the fasteners
144 could be in the form of clips 143 or bolts 145. For example, in
the exploded views of FIGS. 6 and 7, the drawings illustrate the
use of bolts 145 extending through apertures 141 of the first and
second housing halves 140, 142, respectively. The use of clips 143
is shown in several other views of the drawings, including FIGS. 8,
10 and 11.
[0092] As also shown in a number of the drawings, including FIGS. 6
and 7, the apertures 141 can be positioned within connecting
flanges 136 which extend around the periphery of both the first
housing half 140 and the second housing half 142. In addition, for
purposes of providing a relatively tight seal for the connection
between the housing halves 140, 142, a series of gaskets 135 may be
utilized. Such gaskets are illustrated in, for example, FIGS. 6, 7,
8 and 10. The gaskets 135 can be utilized in a conventional manner
and positioned intermediate the connecting flanges 136 of the first
housing half 140 and second housing half 142 when the halves are
coupled together.
[0093] In addition to the elements of the energy exchanger assembly
100 primarily utilized for coupling together the halves of the
exchanger housing 138, the energy exchanger assembly 100 also
includes other additional components separate from components
associated specifically with the core plates 160. For example, the
thermal energy exchanger assembly 100 may also include an air
filter assembly 147. The air filter assembly 147 (or individual
components thereof) is primarily shown in FIGS. 6-10 and 16. With
reference thereto, the air filter assembly 147 includes an air
filter 149 which is positionable in front of what is shown as the
first core plate 162. The air filter 149, when positioned in front
of the first core plate 162, is utilized to filter dust and
allergens from the incoming fresh airstream 122. The air filter 149
is supported at its opposing ends by a pair of filter support
brackets 151. As shown particularly in FIG. 16, each of the filter
support brackets 151 includes a tubular aperture 153 extending
lengthwise from the top to the bottom of each filter support
bracket 151. The tubular apertures 153 can be utilized to support
elongated bolts or similar connecting means (not shown) for
purposes of securing the filter support brackets 151 to the
exchanger housing 138. As further shown in FIG. 16, each of the
filter support brackets 151 also includes a filter channel 155. The
filter channels 155 of each support bracket 151 face towards each
other and are utilized to capture the ends of the air filter 149 as
the air filter 149 may be slid into appropriate position in front
of the first core plate 162.
[0094] The thermal energy exchanger assembly 100 also includes
means for removing and replacing air filters 149, without requiring
the disassembly of the housing halves 140, 142 of the thermal
energy exchanger assembly 100. More specifically, and again as
shown in several of the drawings, including FIGS. 6 and 7, the
first housing half 140 is illustrated as having a filter slot 157
with an elongated length and positioned immediately above the
filter support brackets 151. The filter slot 157 includes a pair of
finger notches 157A. When it is desired to utilize the air filter
149 with the exchanger assembly 100, the air filter 149 can be slid
into the filter support brackets 151 (and, specifically, the filter
channels 155) through the filter slot 157. When it is desired to
remove the filter, the user can grasp the air filter 149 (with the
finger notches 157A facilitating the removal) and pull the air
filter 149 outwardly through the slot 157. For purposes of
maintaining the interior of the exchanger housing 138 as clean as
possible, the filter slot 157 can be covered by a removable filter
cover 161. The filter cover 161 can be secured to the surface of
the first housing half 140 through manually operable locking
latches 161A or similar known securing means. Although the
foregoing has described an air filter assembly 147 which may be
utilized in accordance with the invention, a number of the novel
concepts of the invention do not require an air filter assembly.
When not required, the exchanger housing 138 can be constructed
without the necessity of a filter slot 157 or the like. Such a
configuration is illustrated in FIG. 5.
[0095] The configuration of the core plates 160 will now be
described in greater detail. More specifically, and as earlier
stated, the core plates 160 are illustrated in a number of
drawings, including FIGS. 4-10 and 16-20. Still further, the core
plates 160 are characterized as comprising a first core plate 162
and an opposing second core plate 164. The core plates 162 and 164,
are positioned within the exchanger housing 138 so as to face each
other, with each of the core plates 160 having a configuration and
disposition substantially parallel to the other one of the core
plates 160. As described in subsequent paragraphs herein, the core
plates 160 are utilized to provide support for the core tubes
utilized in accordance with the invention, and also utilized to
form appropriate air barriers within the exchanger housing 138.
These barriers define particular spatial areas for movement of the
stale airstream 114 and the fresh airstream 122.
[0096] Each of the core plates 160 may include one or more
components of what could be characterized as a frame assembly 166.
The frame assembly 166 is shown in various parts in FIGS. 10 and
16. If desired, the frame assembly 166 for each of the core plates
160 can be utilized to provide a framing and positioning structure,
and also to facilitate the sealing of various air spaces associated
with the thermal energy exchanger assembly 100. The frame assembly
166 associated with one of the core plates 160 can be substantially
identical to the frame assembly 166 of the other of the core plates
160. With reference to FIG. 10, the frame assembly 166 can include
what is characterized herein as a lower frame channel 168. The
lower frame channel 168 can be utilized to capture one end or side
of other components forming the core plates 160. The lower frame
channel 168 can include a series of apertures 169 (FIG. 10) through
which threaded rods or similar means can be utilized for purposes
of maintaining the assembly of the core plates 160. If desired,
each of the core plates 160 can also include what is characterized
herein as an upper frame channel 170, primarily shown in FIG. 16.
The upper frame channel 170 can be substantially identical to the
lower frame channel 168, and can be provided to essentially capture
one side of other components of the core plate 160. As with the
lower frame channel 168, the upper frame channel 170 can also
include a series of apertures 169 through which threaded rods can
be utilized for purposes of assembly of the core plates 160.
[0097] Still further, if desired, the frame assembly 166 can also
include a pair of opposing side fillers 172. Such example side
fillers 172 are illustrated in FIG. 16. The side fillers 172 can be
utilized to provide additional support for assembly of other
components of the core plates 160. The side fillers 172 can also be
formed of a cushion or similar type of material so as to provide a
relatively tight seal between the sides of the core plates 160 and
the side surfaces of the exchanger housing 138. Providing
relatively air tight sealing between the air spaces through which
the fresh airstream 122 and the stale airstream 114 flow improves
efficiency of the energy exchanger assembly 100. Again, however, it
should be emphasized that utilizing a frame assembly 166 and the
particular frame components consist of options for the thermal
energy exchanger assembly 100, and are not required to provide an
exchanger assembly incorporating the principal concepts of the
invention.
[0098] In addition to the optional frame assembly 166, each of the
core plates 160 comprises what can be characterized as a core
support assembly 174. The core support assembly 174 for the first
core plate 162 is identical to the core support assembly for the
opposing second core plate 164. FIG. 4 illustrates the two core
support assemblies 174, in the absence of the optional frame
assemblies 166. The core support assemblies 174 are shown, in whole
and in part, in FIGS. 4-10 and 16-20.
[0099] When assembled, each of the core support assemblies 174 has
what can be characterized as a honeycomb configuration 176. The
honeycomb configuration 176 further forms a set of apertures or
cylinders 178 having what can be characterized as an annular
configuration.
[0100] The apertures or cylinders 178 within the honeycomb
configuration 176 are utilized to support core tubes 180. The core
tubes 180 are primarily shown in FIGS. 6-9 and 17-21. The core
tubes 180 form what can be characterized as a tube assembly 182.
The structure and function of the core tubes 180 will be described
in subsequent paragraphs herein, as well as the assembly and
structure of each of the core support assemblies 174.
[0101] Prior to the description of the core support assemblies 174
and tube assembly 182, the separated air spatial areas and the
general concepts of the use of the core tubes 180 will be
described. More specifically, and as shown in part in FIGS. 8 and
16, the filler pieces 172 of each of the core plates 160 abuts
against an interior surface of the first and second housing halves
140, 142, respectively, of the exchanger housing 138. Such abutment
positions are illustrated in FIG. 5 as positions 184 and 186.
Correspondingly, and as shown with respect to the frame piece 168
in FIG. 10, the frame piece 168 can be connected to or otherwise
sealed against a surface of the exchanger housing 138. Similarly,
the frame piece 170, although not specifically shown in the
drawings, can be made to connect to or otherwise seal against an
opposing interior surface of the exchanger housing 138. These
abutments form what may be characterized as relatively air tight
seals.
[0102] At this time, it should also be stated that air tight seals
are provided between the core tubes 180 and the apertures or
cylinders 178 of the core support assemblies 174 into which the
ends of the core tubes 180 are positioned. In this regard, it
should be noted at this time that the preferred method of assembly
of the core tubes 180 with the core support assemblies 174 is to
"lay in" the core tubes 180 as the individual core supports 194 or
200 (described subsequently herein) are interlocked together. This
method of assembly will facilitate appropriate fitting of the core
tubes 180 into the cylinders 178 resulting from the interlocking
coupling of the individual core supports 194 or 200 so as to form
the core support assemblies 174. More specifically, the outer
diameter of each of the core tubes 180 will be somewhat slightly
larger than the inner diameter of each of the apertures or
cylinders 178. With the core tubes 180 composed of plastic
materials, the tubes 180 exhibit a certain amount of resiliency.
Accordingly, the core support tubes 180 are inserted into the
apertures or cylinders 178 in what may be characterized as a
"compression fit." Without a need for any type of complex
structure, and in accordance with the invention, this capability of
having a compression fit between the core tubes 180 and apertures
or cylinders 178 provides a relatively air tight seal. Accordingly,
with these air tight seals, air from the fresh air stream 122
(which is to flow through the core tubes 180) will not "leak" into
the area between the core support assemblies 174 around and outside
of the core tubes 180.
[0103] With the sealing of the core plates 160 to the interior
surfaces of the exchanger housing 138, and with the compression
seals between the core tubes 180 and the core support assemblies
174, a set of what can be characterized as three spatial areas are
formed within the interior of the housing 138 of the exchanger
assembly 100. More specifically, one of the spatial areas can be
characterized as a stale air area 188 as identified in FIG. 5. This
stale air area 188 is formed between the opposing pair of core
plates 160. Also, the stale air area 188 is open to the incoming
stale air duct 148 and the outgoing stale air duct 152. It is
therefore apparent that it is this area 188 through which the stale
airstream 114 flows through the exchanger assembly 100. It is
during the period of time that the stale airstream 114 is flowing
through the stale air area 188 that the stale airstream 114 will
also be flowing around the tube assembly 182. As described in
subsequent paragraphs herein, it is this flow around the tube
assembly 182 which will cause an energy exchange between the stale
airstream 114 and the fresh airstream 122.
[0104] In addition to the stale air area 188, the relative
structural configuration between the core plates 160 and the
housing 138 also forms an incoming fresh air area 190 (FIG. 5). The
incoming fresh air area 190 is formed within the housing 138
between the incoming fresh air duct 146 and the second core plate
164. A third area, characterized as the outgoing fresh air area
192, is formed between the first core plate 162 and the outgoing
fresh air duct 150. In accordance with the foregoing, as the fresh
airstream 122 enters the incoming fresh air duct 146, the airstream
122 will travel through the incoming fresh air area 190 and into
the individual core tubes 180 of the tube assembly 182. This fresh
airstream 122 will then exit the individual core tubes 180 and flow
through the outgoing fresh air area 192 and into the outgoing fresh
air duct 150. Accordingly, it is the fresh airstream 114 which
flows through the individual core tubes 180. As previously
described, the stale airstream 114 will enter the stale air area
188 through the incoming stale air duct 148. This stale airstream
114 will then flow around the core tubes 180, thereby exchanging
energy between the stale airstream 114 and a fresh airstream 122.
The stale airstream 114 will then be exhausted outwardly through
the outgoing stale air duct 152.
[0105] The foregoing concepts of the "cross-coupling" of the stale
airstream 114 and the fresh airstream 122 utilizing the core tubes
180, is diagrammatically illustrated in FIG. 21. As shown therein,
the fresh airstream 122, consisting of fresh, outside air, flows
into one end of each of the core tubes 180. Correspondingly, stale
air 114 flows into the stale air area 188 and around the exterior
of each of the core tubes 180. During this flow, and given the
particular construction of the core tubes 180, energy is exchanged
between the stale airstream 114 flowing around the core tubes 180,
and the fresh airstream 122 flowing through the core tubes 180. For
example, if the stale airstream 114 is warmer than the fresh
airstream 122, heat will be removed from the stale airstream 114
and absorbed through the core tubes 180 into the fresh airstream
122. Accordingly, as the fresh airstream 122 exits each of the core
tubes 180, the fresh airstream 122 will have been warmed and of a
higher temperature. Correspondingly, after the warm, stale air in
the form of the stale airstream 114 has passed around the core
tubes 180 of the tube assembly 182, the stale airstream 114, having
been somewhat cooled, is then exhausted to the outside. Conversely,
if the stale airstream 114 is cooler than the fresh airstream 122,
heat will be removed from the fresh airstream 122 flowing through
the core tubes 180, and absorbed through the surfaces of the core
tubes 180 into the stale airstream 114. Accordingly, as the fresh
airstream 122 exits each of the core tubes 180, the fresh airstream
122 will have been cooled and will be of a relatively cooler
temperature. Correspondingly, after the cool, stale air in the form
of the stale airstream 114 has passed around the surfaces of the
core tubes 180 of the tube assembly 182, the stale airstream 114
will have absorbed a certain amount of thermal energy and will then
be exhausted to the outside. In either situation, the fresh
airstream 122, after exiting the core tubes 180, is then guided
through the appropriate plenums and duct work (previously described
herein) into the interior 106.
[0106] Preferably, each of the core tubes 180 is of a tubular or
cylindrical design. The composition of each of the core tubes 180
is such that each may comprise an ultra thin plastic composition,
which conserves energy loss by transferring the thermal energy
between the stale airstream 114 and the fresh airstream 122 flowing
through the core tubes 180. In accordance with certain aspects of
the invention, the core tubes 180 not only consist of a relatively
thinner wall thickness than known tubular systems, but also provide
for substantially greater surface area as the core tubes 180 are
assembled into the core support assemblies 174. Also, the use of
relatively thinner wall thicknesses results in core tubes 180
having relatively larger inner diameters and volume. These
resultant larger air paths for the fresh airstream will assist in
preventing the core tubes 180 from "freezing shut" during use in
cold climates. Although it is possible that various types of
plastic materials may be utilized for the core tubes 180, it is
believed that it may be preferable for the core tubes 180 to be
manufactured using a polypropylene composition.
[0107] The core support assemblies 174, and the components
associated therewith, will now be described with respect to FIGS.
17-20, and primarily with respect to FIGS. 22-29. As earlier
stated, each of the core plates 160 includes a core support
assembly 174. The core support assembly 174 consists of a series of
individual core supports. Two illustrative embodiments of core
supports which may be utilized in accordance with the invention
will be described herein. A first embodiment of an individual core
support is illustrated as core support 194. The core support 194 is
primarily shown in FIGS. 17-20, 22 and 23. A second illustrative
embodiment of an individual core support in accordance with the
invention is illustrated as core support 200. The core support 200
is shown in FIGS. 24-29. The core supports 194 and 200 are
substantially identical in design and construction. However, the
core support 194 includes, as primarily shown in FIGS. 22 and 23, a
pair of opposing ends 196 having what can be characterized as
beveled surfaces 198. The beveled surfaces 198 essentially are
positioned so as to be at a 45.degree. angle relative to a
longitudinal axis extending along the elongated dimension of the
core support 194. These beveled surfaces 198 can be utilized to
facilitate sealing of the ends 196 to interior surfaces of the
housing halves of the exchanger housing 138. That is, the use of
the beveled surfaces 198 provides for a "flat" abutment between the
interior surfaces of the housing 138 and the core support 194,
since the core supports 194 are angularly positioned within the
housing 138 relative to certain of the interior surfaces thereof.
Additional details regarding the general structure of the core
support 194 will be described in subsequent paragraphs herein.
[0108] The second illustrative embodiment of a core support in
accordance with the invention, namely the core support 200,
includes end assemblies 202 which can be characterized as being
"squared off," in contrast to the beveled configuration for the
ends 196 of the core support 194. Turning to more specific details
regarding the core support 200, each of the supports 200, as
assembled so as to form each core support assembly 174, is of a
configuration identical to the others of the core supports 200. The
principal function of the core supports 200, when assembled
together to form the core support assemblies 174, is to
appropriately secure the core tubes 180 to each of the core plates
160, with a configuration which efficiently provides for energy
transfer between the stale airstream 114 flowing around the outer
surfaces of the tubes 180, and the fresh airstream 122 flowing
through the interiors of the core tubes 180.
[0109] Turning first to FIGS. 24, 25 and 26, each of the core
supports 200 includes an elongated main body 204.
[0110] At opposing ends of each core support 200 (only one end of
which is shown in FIGS. 25 and 26) is a configuration which can be
characterized as an end assembly 202. The end assemblies 202 at the
opposing ends of each core support 200 are identical. Each end
assembly 202 includes a wide end bracket 206 which extends
angularly outwardly from the main body 204. As particularly shown
in FIGS. 25 and 26, the wide end bracket 206 is of a rectangular
configuration (integral to the main body 204) and has a lip 214
formed along one surface of the bracket 206 and along an outer edge
thereof. The lip 214 and the main body of the wide end bracket 206
form a slot 216 as again primarily shown in FIGS. 25 and 26. The
wide end bracket 206 can be characterized as extending angularly
outwardly from a surface side 230 of the main body 204. Extending
outwardly from the same side 230 but on an opposing edge relative
to the edge from which the wide end bracket 206 extends is an end
flange 218. The end flange 218 has an elongated configuration and
forms what can be characterized as a catch edge 220 between the
flange 218 and the surface of the side 230. This configuration of
the end flange 218 is primarily shown in FIG. 26.
[0111] Turning to FIG. 25, an additional side 232 of the main body
204 is shown as a top side with the orientation of the core support
200 shown in FIG. 25. The side 232 is essentially perpendicular to
the side 230 previously described with respect to FIG. 26. As
further shown in FIG. 25, the end assembly 202 further includes
what could be characterized as a narrow end bracket 222 extending
angularly from one edge of the side 232. The narrow end bracket 222
can be characterized as having a lip 224 formed along the outer
edge of the end bracket 222. The lip 224 and one surface of the end
bracket 222 form what can be characterized as a slot 226. As with
other elements described with respect to the core support 200, the
narrow end bracket 222 is preferably integral with the main body
204 and other components of the core support 200.
[0112] Still further, the end assembly 202 includes an aperture
228. As will be described subsequently herein, the aperture 228
formed in each end assembly 202 of each core support 200 is
utilized to receive a threaded rod, bolt or similar structure for
purposes of ensuring that the core supports 200 of each core
support assembly 174 remain tightly secured to each other. Also,
these threaded rods or bolts can be utilized to secure each core
support assembly 174 to the exchanger housing 138. Further, the use
of the threaded rods or bolts help to ensure that appropriate air
tight seals are provided around the core tubes 180 when they are
inserted into the core support assemblies 174. That is, pressure
will be applied to the interconnected core supports 200 of each
core support assembly 174 when the threaded rods or bolts are
tightened together through the use of nuts or other appropriate
connecting means. Further, however, it should be noted that the use
of the threaded rods or bolts may be considered optional and is
somewhat secondary to the principal concepts of the invention. That
is, appropriate air tight sealing between the individual core
supports, and the air tight sealing provided by a compression fit
between the core supports and core tubes may be sufficient without
the need of the threaded rods or bolts. As shown in FIG. 26, the
end aperture 228 opens into what can be characterized as a wide end
chamber 208. The end assembly 202 also includes what may be
characterized as a narrow end chamber 210. The wide end chamber 208
and narrow end chamber 210 are separated by a web 212. The chambers
208, 210 are formed as part of the molding process for the
preferably plastic core support 200. The fact that the chambers
208, 210 are hollow reduces the weight of each core support 200 and
also reduces the amount of plastic mold required for construction
of the core support 200.
[0113] The remaining portions of the core support 200 will now be
described, primarily with respect to FIGS. 25 and 26. Turning
thereto, and although the core support 200 has an integral
configuration, the support 200 can be characterized as having a
series of identical sections, referred to herein as coupling
sections 240. Subsequent paragraphs herein will describe the
elements of one of the coupling sections 240. However, it should be
understood that the coupling section 240 is repeated along the
elongated length of the core support 200, so as to provide for a
core support 200 of desired length. Also, for purposes of
description, and with reference to FIG. 25, the core support 200
will be characterized as having a top portion facing upwardly in
the view of FIG. 25, and a bottom side facing downwardly in the
view of FIG. 25.
[0114] With these reference directions, each coupling section 240
includes a set of four cylinder halves. On the top side of the
coupling section 240 are a pair of first cylinder halves 234. Each
of these cylinder halves 234 provides half of the inner surface of
the cylinders within which the core tubes 180 will be received. On
the bottom side of each coupling section 240 are a pair of second
cylinder halves 236. The cylinder halves 234, 236 alternate in
position lengthwise along the core support 200.
[0115] With further reference to FIGS. 25 and 26, each coupling
section 240 includes a first bracket 238 which extends angularly
upwardly as shown in FIG. 25. The first bracket 238 can be
characterized as having a lip 242. The lip 242 and the first
bracket 238 form a slot 244, best seen in FIG. 26. Correspondingly,
the coupling section 240 also includes a second bracket 246, shown
in FIG. 26 but hidden from view in FIG. 25. The second bracket 246
has a configuration substantially identical to the first bracket
238. That is, the second bracket 246 includes a lip 248 which
forms, with the main body of the second bracket 246, a slot
250.
[0116] Still further, each coupling section 240 includes a third
bracket 252 angled outwardly and upwardly as viewed in FIG. 25. The
third bracket 252 is hidden from view in FIG. 26. In addition to
the foregoing, each coupling section 240 also includes a fourth
bracket 258. The fourth bracket 258 is illustrated in both FIGS. 25
and 26. The fourth bracket 258 is substantially identical to the
other brackets 238, 246 and 252, and includes a lip 260 which forms
a slot 262 with the main body of the fourth bracket 258. In the
view of FIG. 25, it is apparent that the first bracket 238 is
located on the same side of the core support 200 as is the fourth
bracket 258. However, the first bracket 238 faces upwardly, while
the fourth bracket 258 faces downwardly. Correspondingly, the
second bracket 246 (shown in FIG. 26) and the third bracket 252
(shown in FIG. 25) are also both on the same side of the coupling
section 240. In the view of FIG. 25, the third bracket 252 extends
upwardly. Although not shown in FIG. 25, the second bracket 246
would be extending downwardly with the core support 200 in the
orientation shown in FIG. 25. As apparent from the drawings, and
viewing elements of the core support 200 as positioned along the
elongated length of the core support 200, the sequence of brackets
would be the first bracket 238, the second bracket 236, the third
bracket 252, and the fourth bracket 258.
[0117] In addition to the brackets, each coupling section 240 also
includes a series of flanges 264. As shown in the drawings, the
flanges 264 are positioned directly across from each of the
brackets 238, 246, 252 and 258. As also shown in the drawings, each
flange 264 includes a catch edge 266. Still further, and as
primarily shown in both FIG. 25 and FIG. 26, each coupling section
240 includes a series of hollow chambers 268. The chambers 268 are
positioned intermediate the flanges 264 and the brackets 238, 246,
252 and 258. As shown in FIG. 25, the chambers 268 include a first
chamber 270 and a second chamber 272, with the chambers open
upwardly in the view of FIG. 25. Correspondingly, and in
alternating positions relative to the chambers 270, 272, FIG. 26
illustrates a third chamber 274 and a fourth chamber 276.
[0118] The foregoing comprise the individual elements of each of
the coupling sections 240. As previously described, the coupling
sections 240 are integral with each other and extend lengthwise
along the longitudinal axis of the core support 200.
[0119] The coupling together of the individual core supports 200 so
as to form a core support assembly 174 will now be described
primarily with respect to FIGS. 27, 28 and 29. As illustrated in
these drawings, three of the core supports 200 are shown as being
coupled and interlocked together. When they are coupled together,
the core supports 200 form cylinders 278 into which the core tubes
180 have been laid in during assembly, so as to form the tube
assembly 182. For purposes of the description, the three core
supports 200 illustrated in FIGS. 27, 28 and 29 are separately
referred to as core supports 200A, 200B and 200C. As shown in FIGS.
27 and 28, the core support 200A is positioned so that its wide end
bracket 206 faces upwardly (as viewed in the illustrations), and
the opposing narrow end bracket 222 faces downwardly. In contrast,
core support 200B is positioned below core support 200A and is
essentially turned "upside down" relative to core support 200A.
Accordingly, for core support 200B, the wide end bracket 206 faces
downwardly and is on an opposing side of the wide end bracket 206
of core support 200A. Similarly, the narrow end bracket 222 of the
core support 200B faces upwardly on an opposing side of the narrow
end bracket 222 of core support 200A. In this position, it is shown
that one of the flanges 218 and corresponding catch edge 220 of the
core support 200A is captured within the slot 226 formed with the
narrow end bracket 222 and lip 224 of the core support 200B.
Similarly, at the forward portion of the core support 200A as
viewed in FIG. 28, the narrow end bracket 222, corresponding lip
224 and corresponding slot 226 are positioned so as to receive the
catch edge 220 of the flange 218 of core support 200B.
[0120] Moving to the coupling of the end assemblies 202 of the core
support 200B and core support 200C, and again with reference to
FIGS. 27, 28 and 29, the wide end bracket 206 of the core support
200B faces downwardly and the lip 214 thereof and corresponding
slot 216 are utilized to capture the catch edge 220 of a flange 218
of core support 200C. At this time, it should be noted that the
orientation of the core support 200C is the same as the orientation
of the core support 200A. That is, core supports 200A and 200C are
vertically "reversed" from the orientation of the core support
200B. Still further, and although only partially shown in FIG. 28,
the wide end bracket 206 of the lower core support 200C (positioned
at the rear of the core support 200C as viewed in FIG. 28) includes
a slot 216 which is utilized to capture a lower flange 218 and
corresponding catch edge 220 of the intermediate core support 200B.
The foregoing describes certain interconnections of the end
assemblies 202 of an example coupling of the three core supports
200A, 200B and 200C.
[0121] The coupling sections 240 of each of the core supports 200A,
200B and 200C have similar coupling interconnections. Again, with
reference to FIGS. 28, 29 and 30, and with reference to an
individual coupling section 240, the first bracket 238 of the
intermediate core support 200B includes a lip 242 and corresponding
slot 244 which are utilized to capture a flange 264 and catch edge
266 of the upper core support 200A. Correspondingly, and again with
reference to FIG. 28, the third bracket 252 of the upper core
support 200A includes a lip 254 and corresponding slot 256 which
extends downwardly and is utilized to capture a flange 264 and
catch edge 266 of the intermediate core support 200B. These
represent the couplings shown in FIG. 28 between the upper core
support 200A and intermediate core support 200B with respect to a
given coupling section 240.
[0122] With respect to the couplings between the intermediate core
support 200B and lower core support 200C, FIGS. 27, 28 and 29
illustrate a second bracket 246 of the lower core support 200C
extending upwardly. The second bracket 246 includes a lip 248 and
slot 250 which capture a flange 264 and catch edge 266 of the
intermediate core support 200B. Correspondingly, FIG. 28 also shows
a fourth bracket 258 of the intermediate core support 200B
extending downwardly. This fourth bracket 258 includes a lip 260
and slot 262 which are utilized to capture a flange 264 and catch
edge 266 of the lower core support 200C. These two foregoing
couplings provide for the coupling interconnections between the
intermediate core support 200B and lower core support 200C. Of
course, it will be apparent from the foregoing description that
similar coupling interconnections are made between brackets and
flanges of the core supports 200B and 200C on the sides of the core
supports 200 opposing those sides which are visible in FIGS. 27, 28
and 29.
[0123] Still further, and as previously described herein, the
coupling interconnections of the core supports 200 form the
cylinders 278 into which the core tubes 180 are received. Also in
accordance with certain aspects of the invention, the inner
diameter of the cylinders 278 is slightly smaller than the outer
diameter of the core tubes 180. Accordingly, when the tubes 180 are
received within the cylinders 278, a "compression fit" occurs. This
compression fit facilitates sealing of the core tubes 180 with the
core assemblies 174, so as to prevent air leakage between spatial
areas of the thermal energy exchanger assembly 100.
[0124] The specific core supports 200 illustrate one embodiment of
core supports that may be utilized in accordance with the
invention. Another embodiment of core supports which may be
utilized in accordance with the invention, and as previously
briefly described herein, are core supports 194 illustrated in
FIGS. 22 and 23. As also previously described herein, the primary
distinction between the core supports 194 and core supports 200
reside in the differences in the end assemblies 196 and 202. As
shown in FIGS. 22 and 23, the end assemblies 196 of the core
supports 194 comprise beveled surfaces 198. This is in contrast to
the "squared off" surfaces of the end assemblies 202 associated
with the core supports 200. However, the coupling sections 240 of
the core supports 200 as previously described herein correspond to
structure and elements of the core support 194 intermediate the end
assemblies 196. Accordingly, FIGS. 22 and 23 utilize numerical
references identical to those used in FIGS. 24-29 for elements of
the core supports 194 which are functionally and structurally
identical to like numbered elements of the core supports 200. In
view of the foregoing description, the specific elements of the
core supports 194 will not be described herein, since they
correspond to the description previously set forth herein for the
core supports 200.
[0125] As apparent from the foregoing, the various structural
elements of the core supports 200 can be sized and configured so
that the coupling together of the core supports 200 provide for
relatively air tight seals. However, in certain instances, it may
be desired to facilitate the air tight sealing and compression fit
of the core tubes 180 within the cylinders 278 through additional
means. An example of such additional means is illustrated in
substantial part in FIGS. 16, 17, 19 and 20. As previously
described herein, the end assemblies 202 of the core supports 200
may include apertures 228. Also, if desired, additional apertures
228 may extend through one or more of the coupling sections 240.
For example, and with respect to the alternative core support 194,
FIG. 22 illustrates an aperture 228 extending through the core
support 194 substantially equidistant apart from each of the end
assemblies 198. These apertures 228 can, if desired, be threaded
(or frame pieces at the upper and lower portions of core support
assemblies 174 may be threaded) and receive threaded or similar
rods 280. The rods 280 may extend through the entire sets of
apertures 228 within a set of core supports 200 or 194 which form a
core support assembly 174. The threaded rods 180 may have rod heads
positioned at one end of the rods 280, and may be secured to the
core support assemblies at their other ends through the use of nuts
282 or the like. Tightening these rods 280 after they have been
received through the apertures 228 will readily facilitate
tightening together of the individual core supports 200 or 194, and
will also provide additional compression forces on the core tubes
180 within the cylinders 278.
[0126] A thermal energy exchanger assembly 100 has now been
described in accordance with the invention, with alternative
embodiments for the core supports (i.e. core supports 194 and core
supports 200). Various concepts are embodied within thermal energy
exchanger assemblies in accordance with various aspects of the
invention. A number of these advantageous concepts have been
previously described herein. For example, with the designs of the
tubes and core plates as shown herein, assembly speed can be
rapidly increased compared to other types of prior art exchanger
assemblies. Employing plastic materials for components of the
energy exchanger assembly significantly reduces the need for
defrosting functions, in view of the significant reduction in
"freeze-up." Further, with metal housings, units are often
subjected to rust, eventually resulting in the mixing of the
airstreams and ultimate failure of the assemblies. With plastic
materials, longevity of the thermal energy exchanger increases, due
to the elimination of components subject to rust.
[0127] Further, with the design of the tube assembly 182 described
herein, a substantial amount of spatial volume is provided for
energy exchange. In addition, in view of the core tubes 180 being
substantially separated from each other, and only required to be
supported at their ends, a substantial amount of surface area is
provided which separates the fresh airstreams from the stale
airstreams. The greater the surface area of the material which
separates the airstreams, the higher will be the flow rate of
thermal energy between the airstreams. Still further, this increase
in space and openings also facilitates reduction of freeze-up. Put
another way, the thin-walled construction of the core tubes
provides for a larger inner diameter for the tubes 180, and more
space around the exterior of the tubes 180. These features result
in a significant reduction in static pressures and airstream flow
resistance, both within and outside the tubes 180. Again, this
reduces freeze-up and the probability of the need for fans or the
like.
[0128] Still further, the thermal energy exchanger assemblies in
accordance with the invention may be operated as "passive"
assemblies. That is, these assemblies require no moving parts, such
as fans or the like. This occurs because of the efficiency of
thermal energy transfer between the airstreams. This capability of
not requiring fans or similar components also reduces the possibly
of rust or other type of metal wear. In addition, and as described
herein, air filters may be utilized with the thermal energy
exchanger assemblies in accordance with the invention. The designs
of the tubes and the use of air filters can improve relative
cleanliness. That is, known plate core designs accumulate dust and
dirt particles which can eventually plug up a core and reduce
exchange efficiency and airflow. Such known thermal energy
exchangers are then relatively difficult to clean, because the
cleaning requires the disassembly of the unit periodically, so as
to maintain efficiency.
[0129] In view of the lack of moving parts, thermal energy
exchanger assemblies in accordance with certain aspects of the
invention may be of relatively low cost. Also, the core tubes 180
may have relatively thin wall plastic materials which utilize "film
heat transfer" technologies. Such tube designs have advantages over
other cores on the market, because they provide for a greater
surface area than current plate technology. Also, due to the
internal diameter of the tubes 180, they will reject "freeze-up" in
cold weather, which again may require defrosting cycles. Still
further, with the tubes 180 supported so as to provide for
relatively additional and larger spaces between and around the
tubes, freeze-up is again significantly reduced. These features
again reduce the probability of a need for a fan.
[0130] With respect to the core plates 160, it is advantageous that
the designs in accordance with certain aspects of the invention
essentially comprise preformed inserts, along for tubes to be
quickly "laid in" and sealed with compression. Further, such a
design will work with current plastic tubes, and with enthalpic
tubes known to be utilized for energy recovery ventilators, as well
as metal tubes such as copper or aluminum, without requiring design
changes to the overall unit.
[0131] As also previously described herein, the core plate
assemblies 174, comprising the core supports 194 or 200, can
essentially be constructed entirely of plastic materials. For
example, the core supports 194 or core supports 200 may be composed
of ABS.
[0132] It will be apparent to those skilled in the pertinent arts
that other embodiments of thermal energy exchanger assemblies in
accordance with the invention may be designed. That is, the
principles of thermal energy exchanger assemblies in accordance
with the invention are not limited to the specific embodiments
described herein. Accordingly, it will be apparent to those skilled
in the arts that modifications and other variations of the
above-described illustrative embodiments of the invention may be
effected without departing from the spirit and scope of the novel
concepts of the invention.
* * * * *