U.S. patent application number 11/428002 was filed with the patent office on 2008-01-03 for insulating window incorporating photovoltaic cells and a pressure equalization system.
This patent application is currently assigned to VISIONWALL CORPORATION. Invention is credited to Gregory L. Clarahan.
Application Number | 20080000195 11/428002 |
Document ID | / |
Family ID | 38875189 |
Filed Date | 2008-01-03 |
United States Patent
Application |
20080000195 |
Kind Code |
A1 |
Clarahan; Gregory L. |
January 3, 2008 |
INSULATING WINDOW INCORPORATING PHOTOVOLTAIC CELLS AND A PRESSURE
EQUALIZATION SYSTEM
Abstract
A heat insulating window comprises a pair of outer glass panes,
held apart by a spacing member and surrounded by a frame enclosing
at least one photovoltaic cell. In a preferred embodiment a conduit
system providing gas communication to the air space between the
glass panes includes a desiccant.
Inventors: |
Clarahan; Gregory L.;
(Edmonton, CA) |
Correspondence
Address: |
EDWARD YOO C/O BENNETT JONES
1000 ATCO CENTRE, 10035 - 105 STREET
EDMONTON, ALBERTA
AB
T5J3T2
US
|
Assignee: |
VISIONWALL CORPORATION
Edmonton
AB
|
Family ID: |
38875189 |
Appl. No.: |
11/428002 |
Filed: |
June 30, 2006 |
Current U.S.
Class: |
52/786.13 ;
257/E31.049 |
Current CPC
Class: |
Y02B 10/10 20130101;
H02S 30/10 20141201; Y02E 10/50 20130101; H01L 31/0488 20130101;
H02S 20/26 20141201 |
Class at
Publication: |
52/786.13 |
International
Class: |
E04C 2/54 20060101
E04C002/54 |
Claims
1. A heat insulation window comprising: (a) a pair of glass panes
defining an interior air space therebetween; (b) a spacing member
disposed between said glass panes which maintain the panes in a
spaced-apart relationship; (c) at least one photovoltaic cell
disposed between said glass panes; and (d) a frame surrounding a
perimeter of the window, wherein the frame comprises a conduit
means for providing gas communication through the frame to the air
space.
2. The heat insulation window of claim 1 wherein said conduit means
comprises a desiccant.
3. The heat insulation window of claims 1 or 2 wherein said at
least one photovoltaic cell is laminated to one of said glass
panes.
4. The heat insulation window of claims 1-3 wherein said frame
encloses an interior space and comprises an access means through
said frame to said interior space.
5. The heat insulation window of claim 1 or 2 wherein the spacing
member defines an internal volume in gas communication with the air
space between the glass panes, and further comprising a dessicant
disposed within the internal volume.
6. The heat insulation window of claim 5 wherein said at least one
photovoltaic cell is electrically connected to a three pole
disconnect direct current switch and an inverter.
7. A heat insulation window comprising: (a) a pair of glass panes
defining an air space therebetween and having a photovoltaic cell
disposed within the airspace; (b) a spacing member disposed between
the glass panes which maintain the panes in a spaced-apart
relationship, the spacing member being hollow and defining openings
permitting gas communication between the air space and the interior
volume of the spacing member; (c) a desiccant material contained
within the spacing member; and (d) a frame surrounding a perimeter
of the window, wherein the frame comprises: (i) at least one
desiccant concealing member which is hollow and detachable from the
frame; ii) a desiccant cartridge removably disposed within the
desiccant concealing member and (iii) conduit means for providing
gas communication between the air space and the desiccant
cartridge.
8. The window of claim 7 wherein the conduit means provides gas
communication between the interior volume of the spacing member and
the desiccant cartridge.
9. The window of claim 7 wherein the desiccant cartridge comprises
an elongated cylindrical tube.
10. The window of claim 7 wherein the desiccant concealing member
is elongated and has a substantially U-shaped cross-sectional
profile.
11. The window of claim 10 wherein the cross-sectional profile
comprises two linear segments joining at a substantially right
angle.
12. The window of claim 7 wherein the frame comprises an outer
channel member, an inner channel member, a web member disposed
between the outer and inner channel members, wherein the desiccant
concealing member is detachably connected to the inner channel
member.
13. The window of claim 10 wherein the desiccant concealing member
is comprised of a resilient material and comprises a first lip and
a second lip which each engage an undercut groove in the inner
channel member.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to window
structures, and more particularly to window structures comprising
photovoltaic panels.
BACKGROUND
[0002] Windows or glass areas are a significant weakness in the
heat insulation schemes for buildings in hot or cold climates. A
basic insulating window that is well-known is constructed from two
panes of glass within a rigid frame. The air space between the
panes provides heat insulation.
[0003] Photovoltaic units, when disposed between the two panes,
heat the air entrapped within the insulating glass unit, which
causes the seal to fail prematurely. U.S. Pat. No. 4,137,098 to
Gillard discloses photovoltaic cells enclosed between two panes of
glass of a window housing that is cooled by a forced air system.
U.S. Pat. No. 5,128,181 to Kunert discloses photovoltaic cells
enclosed between two panes of glass of a window housing in which
excess solar radiation is dissipated outwardly by convection. U.S.
Pat. No. 5,221,363 to Gillard discloses photovoltaic cells enclosed
between two panes of glass of a window housing having valves so
that excess heat may be removed by convection. However, if the
entrapped air is vented, when the window cools and air reenters the
unit, condensation may occur which impairs the transparency of the
window unit.
[0004] Therefore there is a need in the art for an insulating glass
unit window structure, which includes a photovoltaic cell and
mitigates the difficulties posed by the prior art.
SUMMARY OF THE INVENTION
[0005] The present invention is directed to a pressure equalized
heat insulation window comprising photovoltaic cells. Therefore, in
one aspect, the invention comprises a heat insulation window
comprising: [0006] (a) a pair of glass panes defining an air space
therebetween; [0007] (b) a spacing member disposed between said
glass panes which maintain the panes in a spaced-apart
relationship; [0008] (c) at least one photovoltaic cell disposed
between said glass panes; and [0009] (d) a frame surrounding a
perimeter of the window, wherein the frame comprising a conduit
means for providing gas communication through the frame to the air
space.
[0010] In one embodiment the conduit means comprises a
desiccant.
[0011] In other embodiments the frame encloses an interior space
and comprises an access means.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The invention will now be described by way of an exemplary
embodiment with reference to the accompanying simplified,
diagrammatic, not-to-scale drawings. In the drawings:
[0013] FIG. 1 is a perspective view of a heat insulation window
enclosing photovoltaic cells and a diagrammatic representation of
electrical connections;
[0014] FIG. 2 is a cross-sectional view of the window of FIG. 1
(photovoltaic cells not shown), showing the interior space enclosed
by the window frame and access means; and
[0015] FIG. 3 is a cross-section of the embodiment of FIG. 2.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0016] The present invention provides for an energy efficient, heat
insulating window design. When describing the present invention,
all terms not defined herein have their common art-recognized
meanings.
[0017] FIG. 1 shows a perspective view of photovoltaic cells (2)
mounted on the inner surface of outer glass pane (12) and a
diagrammatic representation of electrical connections (4).
[0018] FIGS. 2 and 3 show the heat insulation window with a
pressure equalization system as described in co-owned Canadian
Patent Application 2,507,108, the contents of which are herein
incorporated by reference.
[0019] FIG. 2 shows a view of a window unit comprising dual glass
panes (10, 12) and a frame (14).
[0020] FIG. 3 shows cross-sections of the glass panes (10, 12)
spaced apart by a spacer (16) and held together by the frame
(14).
[0021] The frame comprises an outer channel member (18), an inner
channel member (20) and dual intermediate web members (22) which
join the inner and outer channel members. The inner channel member
may include an installation flange (24) which projects outwardly
and will abut a window jamb (not shown) when installed into a wall
frame. A removable desiccant concealing member (26) is attached to
the inner channel member (20) opposite the installation flange (24)
which serves to retain the glass unit but does not serve any other
structural function. The desiccant concealing member (26) is
tube-shaped defining a single elongate channel (28). One edge of
the channel defines a first lip (30) while the other edge of the
channel defines a second lip (32). The two lips (30, 32) mate with
corresponding grooves (31, 33) formed in the inner channel member
(20). The glass planes are positioned and retained by resilient
seals (34, 36, 38). Seal (34) is attached to the outer channel
member (18) while seal (36) is attached to the inner channel member
(20). Air seal (38) is attached to the desiccant concealing member
(26). The seals are preferably formed from a material having low
thermal conductivity and relatively impervious to moisture, such as
neoprene, EPDM or silicone rubber.
[0022] In a preferred embodiment, a dual desiccant system is
employed. The spacer (16) is a hollow rectangular member which is
filled with a suitable desiccant (40). The spacer defines pores
which allow air to circulate between the air space between the
glass panes (10, 12) and the interior volume of the spacer (16)
which contains the desiccant. As well, a small conduit (42)
connects the interior space of the spacer to a sealed tube (44)
within the desiccant concealing member (26) which is filled with
desiccant (40). The sealed tube (40) has a cap (46) which receives
the conduit (42) thereby providing gas communication between the
spacer interior volume and the desiccant tube (44).
[0023] As is apparent, the desiccant concealing member (26) may be
removed from the frame (14) by disengaging the lips (30, 32) from
the inner channel member (20), thereby exposing the desiccant tube
(44). The desiccant tube (44) can then be easily disconnected from
the conduit (44) and replaced with a fresh desiccant tube if
necessary. In one alternative embodiment, the desiccant in the
desiccant tube may be different from the desiccant contained in the
spacer and has a higher affinity for water than the desiccant in
the spacer. As will be appreciated by those skilled in the art, air
which is drawn into the air space must pass through the replaceable
desiccant tube, thereby preserving the dry atmosphere within the
window unit.
[0024] Desiccant tubes (44) may be placed in one, two, three or all
four desiccant concealing (20) members (26) in any orientation.
[0025] The outer, intermediate and inner channel members which
comprise the frame (14) may be formed from a thermoplastic material
having low thermal conductivity such as polyvinylchloride or
polyamide. Alternatively, the inner and outer channel members may
be metallic members such as aluminum while the intermediate member
is non-metallic, thereby avoiding a thermal bridge between the two.
The desiccant concealing members may be any suitable material such
as a metal or a plastic, and is preferably resilient to facilitate
its installation and removal from the inner channel member.
[0026] A solar cell, or photovoltaic cell (2), is a semiconductor
device consisting of a large-area p-n junction diode, which, in the
presence of sunlight is capable of generating usable electrical
energy. Any suitable type photovoltaic cell (2) can be used in the
window described herein. For example, silicon, calcium sulfide,
gallium arsenide and other types of cells are suitable. The cells
can be of any desired configuration such as square, circular.
[0027] The photovoltaic cells may be any suitable cell, such as
crystalline wafers, or thin film cells. As an alternative to using
crystalline photovoltaic cell wafers, photovoltaic laminated glass
can also be produced using thin-film solar photovoltaic (PV) cells.
The fabrication of a thin-film solar cell involves depositing very
thin, consecutive layers of atoms, molecules, or ions of
semiconductor material (such as amorphous silicon, copper indium
diselenide, or cadmium telluride) on a low-cost substrate, such as
glass, metal, or plastic. Thin-film cells have certain advantages
over crystalline solar cell wafer technologies. They use less
material and the cell's active area is usually only 1 to 10 microns
thick, whereas conventional wafers are as much as 200 to 400
microns thick. Thin-film cells are also usually amenable to
large-area fabrication (more than 1 m.sup.2) and are suitable for
automated, continuous production, arraying, and packaging. They can
also be deposited on flexible substrate materials.
[0028] In one embodiment, the photovoltaic cells (2) are disposed
between the two glass panes of glass (10, 12) as a photovoltaic
laminate, with the photovoltaic cells laminated between two glass
panels. In conventional laminated glass products a sheet of glass
is bonded to a layer of polymer adhesive film, and a further sheet
or layer of material is bonded to the other side of the adhesive
film layer, so that the adhesive film is sandwiched between two
outer layers. A number of methods for producing such laminates are
known, for example, see U.S. Pat. Nos. 5,268,049; 5,118,371;
4,724,023; 4,234,533; and 4,125,669. Laminated glass has been
generally manufactured by a process wherein a stack of at least two
sheets of glass having a plastic film called an intermediate film
or laminating film, typically a plasticized polyvinyl butylal (PVB)
film, is sandwiched between each pair of adjacent sheets of glass
which is subjected to evacuation, pressing and heating.
[0029] The photovoltaic cells (2) are usually electrically
connected (4) together in a series circuit to achieve desired
voltage, and a plurality of series circuits of photovoltaic cells
can then be connected in parallel, as desired. The electrical
energy can then be fed by electric lines (4) from + and - terminals
to a power control or other suitable distribution device (6). Such
conventional electrical circuitry, would preferably include an
isolator, to a main power bus. As well known in the art, an
inverter would be used to produce alternating current (AC) from
direct current (DC) produced by the photovoltaic cells. Preferably,
a plurality of photovoltaic cells are grouped in parallel to raise
the voltage and each group is provided with a three pole disconnect
DC switch and an inverter, the AC current then passing to a 208
volt distribution panel.
[0030] As will be apparent to those skilled in the art, various
modifications, adaptations and variations of the foregoing specific
disclosure can be made without departing from the scope of the
invention claimed herein. The various features and elements of the
described invention may be combined in a manner different from the
combinations described or claimed herein without departing from the
scope of the invention.
* * * * *