Abstract
A safety barrier heat exchanger for a heating appliance such as a fireplace or furnace is provided. The safety barrier heat exchanger includes a housing configured for attachment across the viewable opening of a fireplace or a barrier window of a furnace, and a plurality of optically transparent, semi-transparent or translucent safety barriers secured within the housing in spaced apart relationship to define a tortuous or serpentine passageway through which a forced bulk flow of ambient air is passed across a viewable opening or barrier window more than one time. Also provided are fireplace systems comprising the safety barrier heat exchanger.
Claims
1. A fireplace assembly comprising: a firebox including a viewable opening, at least one opening in a lower portion of the firebox for combustion air and at least one opening in an upper portion of the firebox for exhausting combustion gases; a firebox glass or optically transparent, semi-transparent or translucent panel disposed across the viewable opening; a housing which is hermetically affixed to the firebox, the housing including a top, which includes an outlet opening, which is adjacent to the firebox, a bottom, a pair of side panels therebetween, a front and an inlet opening, the inlet opening and the outlet opening in fluid communication with an ambient environment; at least two glass or optically transparent, semi-transparent or translucent panels which are retained in the housing, an inner panel disposed across the firebox glass and an outer panel disposed across the inner panel, wherein the two panels, with the firebox glass, define a single serpentine passageway extending between and in fluid communication with the inlet opening and the outlet opening; and at least one forced air circulating fan or blower secured to the housing and operatively configured to urge an airflow through the serpentine passageway from the at least one inlet opening to the at least one outlet opening such that adjacent airflows are counter-current to one another.
2. The fireplace assembly of claim 1, wherein there are two glass or optically transparent, semi-transparent or translucent panels, and the inlet opening enters into a channel between the inner panel and the outer panel proximate to the top of the housing or in the top of the housing.
3. The fireplace assembly of claim 1, further comprising a middle panel, the middle panel disposed between the inner panel and the outer panel, and the inlet opening enters into a channel between the middle panel and the outer panel proximate to the bottom of the housing or in the bottom of the housing.
4. The fireplace assembly of claim 1, wherein there are n odd number of glass or optically transparent, semi-transparent or translucent panels, and the inlet opening enters into a channel between an nth panel and the nth−1 panel, proximate to the bottom of the housing or in the bottom of the housing.
5. The fireplace assembly of claim 1, wherein there are n even number of glass or optically transparent, semi-transparent or translucent panels and the inlet opening enters into a channel between an nth panel and the nth−1 panel proximate to the top of the housing or in the top of the housing.
6. The fireplace assembly of claim 5, wherein the fan or blower is retained on the front of the housing proximate to the bottom.
7. A method of exchanging heat in a single flow of air, the method comprising: selecting the fireplace assembly of claim 1; combusting a material in the firebox; drawing air from an ambient environment into the single serpentine passageway; and urging the single flow of gas through the single serpentine passageway and out into the ambient environment.
8. A combined safety barrier-heat exchanger for a heating appliance, the combined safety barrier-heat exchanger comprising: a housing for attachment to a firebox, the housing including a top, which includes an outlet opening, a bottom, a pair of side panels therebetween, a front and an inlet opening, the inlet opening and the outlet opening in fluid communication with an ambient environment; at least three glass or optically transparent, semi-transparent or translucent panels which are retained in the housing, an inner panel, a middle panel and an outer panel wherein the middle panel is disposed between the inner panel and the outer panel, and the inlet opening enters into a channel between the middle panel and the outer panel proximate to the bottom of the housing or in the bottom of the housing wherein the panels define a single serpentine passageway extending between and in fluid communication with the inlet opening and the outlet opening; and at least one forced air circulating fan or blower secured to the housing and operatively configured to urge an airflow through the serpentine passageway from the at least one inlet opening to the at least one outlet opening such that adjacent airflows are counter-current to one another.
9. The combined safety barrier-heat exchanger of claim 8, wherein there are n odd number of glass or optically transparent, semi-transparent or translucent panels, and the inlet opening enters into a channel between an nth panel and the nth−1 panel, proximate to the bottom of the housing or in the bottom of the housing.
10. The combined safety barrier-heat exchanger of claim 8, wherein there are n even number of glass or optically transparent, semi-transparent or translucent panels and the inlet opening enters into a channel between an nth panel and the nth−1 panel proximate to the top of the housing or in the top of the housing.
11. The combined safety barrier-heat exchanger of claim 10, wherein the fan or blower is retained on the front of the housing proximate to the bottom.
12. A method of exchanging heat in a single flow of air, the method comprising selecting the combined safety barrier-heat exchanger of claim 8; affixing the housing to a firebox; combusting a material in the firebox; drawing air from an ambient environment into the single serpentine passageway; and urging the single flow of gas through the single serpentine passageway and out into the ambient environment.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) For a fuller understanding of the nature and advantages of the disclosed subject matter, as well as the preferred modes of use thereof, reference should be made to the following detailed description, read in conjunction with the accompanying drawings. In the drawings, like reference numerals designate like or similar steps or parts.
(2) FIG. 1 is a schematic cutaway perspective view of a fireplace comprising a 3-panel fireplace safety barrier heat exchanger in accordance with one embodiment of the presently described subject matter.
(3) FIG. 2 is a vertical cross sectional side view of the fireplace of FIG. 1.
(4) FIG. 3 is a horizontal cross sectional side view of the fireplace of FIG. 1.
(5) FIG. 4 is a schematic cutaway perspective view of a fireplace comprising a 4-panel fireplace safety barrier heat exchanger in accordance with another embodiment of the presently described subject matter.
(6) FIG. 5 is a vertical cross sectional side view of the fireplace of FIG. 6.
(7) FIG. 6 is a schematic cutaway perspective view of a fireplace comprising a refractory chamber and a 3-panel fireplace safety barrier heat exchanger in accordance with another embodiment of the presently described subject matter.
(8) FIG. 7 is a vertical cross sectional side view of the fireplace of FIG. 4.
(9) FIG. 8 is a schematic flow diagram of a safety barrier heat exchanger in accordance with embodiments of the presently described subject matter.
DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS
(10) The following description of preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. The safety barrier heat exchanger of the present invention may take form in a number of different embodiments depending upon the particular requirements of the use.
(11) With reference to FIGS. 1-3, there is illustrated a fireplace with fireplace safety barrier heat exchanger 100 in accordance with one embodiment of the presently described subject matter. The illustrated fireplace 100 is a gas burning fireplace connected to a fuel source (not shown), and comprises a firebox 102 and further defines a viewable opening 104 that provides visibility to the interior of the firebox 102 and a fire feature and/or flame 103 when fireplace 100 is in operation. In various embodiments, a fire feature 103 can comprise a burner, fire rock or fire glass, ceramic gas fireplace logs, and the like. Firebox 102 and viewable opening 104 can have any of a number of configurations in accordance with various embodiments. In the illustrated embodiment, viewable opening 102 is shown on a single side of firebox 102 for simplicity, but as is well known in the art, firebox 102 may have viewable openings on multiple sides in any of a variety of viewable opening configurations that are known in the art.
(12) In the embodiment of FIGS. 1-3, the fireplace system with safety barrier heat exchanger 100 generally comprises a firebox 102 having a viewable opening 104; a glass panel 106 disposed across the viewable opening which, in combination with the firebox, forms a combustion chamber 108; at least one opening (not shown) in a lower portion of the firebox 102 for permitting combustion air to pass into the combustion chamber 108, and at least one opening 110 in an upper portion of the firebox 102 for exhausting combustion gases from the combustion chamber 108; and a safety barrier heat exchanger disposed across the glass panel 106 and viewable opening 104 of the firebox 102, the safety barrier heat exchanger comprising: a housing affixed to the firebox, the housing 112 comprising top 114, bottom 116 and two opposite side panels 118, 120 (FIG. 3); a first transparent safety barrier 122 secured within the housing 112 by upper 124, lower 126 and two opposing side first safety barrier brackets 128, 130, wherein the first safety barrier 122 is separated from the glass panel 106 of the firebox 102 by an offset dimension to define a first interstitial space 132 between the glass panel 106 and the first safety barrier 122; a second transparent safety barrier 134 secured within the housing 112 by upper 136, lower 138 and two opposing side second safety barrier brackets 140, 142, wherein the first safety barrier 122 and the second safety barrier 134 are separated by an offset dimension and define a second interstitial space 144 between the first safety barrier 122 and the second safety barrier 134; at least one inlet opening 146 at a first end 148 of the housing 112 in fluid communication with the second interstitial space 144; at least one exit opening 150 at the first end 148 of the housing 112 in fluid communication with the first interstitial space 132; at least one opening 152 (FIG. 3) at a second end 154 of the housing 112 connecting the first 132 and second 144 interstitial spaces in fluid communication to define a serpentine safety barrier heat exchanger passageway 156 (arrows); and at least one forced air circulating fan or blower 158 secured within the housing 112 and operatively configured to force air through the serpentine safety barrier heat exchanger passageway 156 from the at least one inlet opening 146 to the at least one exit opening 150.
(13) Referring now to FIGS. 4-5, a fireplace system with safety barrier heat exchanger 200 in accordance with various embodiments of the present disclosure is illustrated. Fireplace system with safety barrier heat exchanger 200 comprises many of the components of fireplace system with safety barrier heat exchanger 100 illustrated and described with reference to FIGS. 1-3; however, fireplace system with safety barrier heat exchanger 200 further comprises a third safety barrier 260. Firebox 202 includes a viewable opening 204; a glass panel 206 disposed across the viewable opening which, in combination with the firebox, forms a combustion chamber 208; at least one opening (not shown) in a lower portion of the firebox 202 for permitting combustion air to pass into the combustion chamber 208, and at least one opening 210 in an upper portion of the firebox 202 for exhausting combustion gases from flame 203 from the combustion chamber 208; and a safety barrier heat exchanger disposed across the glass panel 206 and viewable opening 204 of the firebox 202, the safety barrier heat exchanger comprising: a housing affixed to the firebox, the housing 212 comprising top 214, bottom 216 and two opposite side panels 218, 220 (not shown); a first transparent safety barrier 222 secured within the housing 212 by upper 224, lower 226 and two opposing side first safety barrier brackets 228, 230 (not shown), wherein the first safety barrier 222 is separated from the glass panel 206 of the firebox 202 by an offset dimension to define a first interstitial space 232 between the glass panel 206 and the first safety barrier 222; a second transparent safety barrier 234 secured within the housing 212 by upper 236, lower 238 and two opposing side second safety barrier brackets 240, 242 (not shown), wherein the first safety barrier 222 and the second safety barrier 234 are separated by an offset dimension and define a second interstitial space 244 between the first safety barrier 222 and the second safety barrier 234; a third transparent safety barrier 260 secured within the housing 212 by upper 262, lower 264 and two opposing side third safety barrier brackets 266, 268 (not shown), wherein the second safety barrier 234 and the third safety barrier 260 are separated by an offset dimension and define a third interstitial space 270 between the second safety barrier 234 and the third safety barrier 260; at least one inlet opening 246 at a second end 247 of the housing 212 in fluid communication with the third interstitial space 270; at least one exit opening 250 at a first end 248 of the housing in fluid communication with the first interstitial space 232; at least one opening 272 at the second end 247 of the housing 212 connecting the first 232 and second 244 interstitial spaces in fluid communication, and at least one opening 274 at a first end 248 of the housing 212 connecting the second 244 and third 270 interstitial spaces in fluid communication to define a serpentine safety barrier heat exchanger passageway 256 (arrows); and at least one forced air circulating fan or blower 258 secured within the housing 212 and operatively configured to force air through the serpentine safety barrier heat exchanger passageway 256 from the at least one inlet opening 246 to the at least one exit opening 250.
(14) With reference to FIGS. 6-7, a fireplace system with safety barrier heat exchanger 300 in accordance with various embodiments of the present disclosure is illustrated. Fireplace system with safety barrier heat exchanger 300 comprises many of the components of fireplace system with safety barrier heat exchanger 100 and 200 illustrated and described above; however, fireplace system with safety barrier heat exchanger 300 further comprises a refractory chamber 380 and an optional firebox top heat exchanger 390. Firebox 302 includes a viewable opening 304; a glass panel 306 disposed across the viewable opening which, in combination with the firebox, forms a combustion chamber 308; at least one opening (not shown) in a lower portion of the firebox 302 for permitting combustion air to pass into the combustion chamber 308, and at least one opening 310 in an upper portion of the firebox 302 for exhausting combustion gases from flame 303 from the combustion chamber 308; a refractory chamber 380 surrounding the firebox 302 except across the at least one viewable opening 304, the refractory chamber 380 comprising at least one refractory chamber ambient air inlet 382 and at least one refractory chamber ambient air outlet 384; and a firebox top heat exchanger 390 disposed above the firebox 302 within the refractory chamber 380. A safety barrier heat exchanger is disposed across the glass panel 306 and viewable opening 304 of the firebox 302, the safety barrier heat exchanger comprising: a housing affixed to the firebox, the housing 312 comprising top 314, bottom 316 and two opposite side panels 318, 320; a first transparent safety barrier 322 secured within the housing 312 by upper 324, lower 326 and two opposing side first safety barrier brackets 328, 330, wherein the first safety barrier 322 is separated from the glass panel 306 of the firebox 302 by an offset dimension to define a first interstitial space 332 between the glass panel 306 and the first safety barrier 322; a second transparent safety barrier 334 secured within the housing 312 by upper 336, lower 338 and two opposing side second safety barrier brackets 340, 342, wherein the first safety barrier 322 and the second safety barrier 334 are separated by an offset dimension and define a second interstitial space 344 between the first safety barrier 322 and the second safety barrier 334; at least one inlet opening 346 at a first end 348 of the housing 312 in fluid communication with the second interstitial space 344; at least one exit opening corresponding to the at least one refractory chamber ambient air inlet 382 at a first end 348 of the housing 312 connecting the first interstitial space 332 and the at least one refractory chamber air inlet 382 in fluid communication; at least one opening 352 at a second end 354 of the housing 312 connecting the first 332 and second 344 interstitial spaces in fluid communication to define a serpentine safety barrier heat exchanger passageway 356 (arrows); and at least one forced air circulating fan or blower 358 secured within the housing 312 and operatively configured to force air through the serpentine safety barrier heat exchanger passageway 336 from the at least one inlet opening 346 to the at least one opening 382, then through optional firebox top heat exchanger 390 and through refractory chamber 380, and finally through the at least one refractory chamber ambient air outlet 384.
(15) FIG. 8 is a schematic flow diagram of a safety barrier heat exchanger in accordance with embodiments of the presently described subject matter. As schematically illustrated, the safety barrier heat exchanger includes an initial optically transparent, semi-transparent or translucent barrier panel “B1” disposed across a viewable opening of a heating appliance such as a fireplace or furnace in which a static or variable heat source “P out” provides thermal, infrared, and/or ultraviolet output; and a plurality of additional optically transparent, semi-transparent or translucent barrier panels “B2” through “Bx”, each of panels B1 through Bx being held in spaced apart relationship from one another by selected suitable offset dimensions within a suitable housing to define a plurality of inter-connected interstitial spaces therebetween. As discussed in relation to various embodiments described above, barrier panel B1 may comprise the panel of heat resistant safety glass commonly employed in a modern insert fireplace (to enclose and seal off the fireplace viewable opening to create a combustion chamber in which the combustible fuel may more efficiently be burned), or barrier panel B1 may comprise an optically transparent, semi-transparent or translucent combustion chamber barrier as a component part of the safety barrier heat exchanger. Including barrier panel B1, at least two additional barrier panels (i.e. B2 and B3) are required in order to create a tortuous or serpentine passage passageway through which a forced bulk flow of ambient air may be passed across a viewable opening more than one time, but a virtually unlimited additional number of barrier panels (i.e. B4 to Bx) may be employed in a safety barrier heat exchanger in accordance with embodiments of the presently described subject matter. Situated opposite the final one of the additional barrier panels (i.e. B4 to Bx) employed in any given safety barrier heat exchanger configuration is the heated zone “Zh”, which typically comprises a residential room or commercial space in which the heating appliance is situated.
(16) Each of barrier panels B1 through Bx may, for example, comprise conventional 6 mm safety glass, but alternative suitable optically transparent, semi-transparent or translucent materials may be used. The interstitial space or gap between adjacent panels B1 through Bx may, for example, be about 20 to about 35 mm; however, alternate spacing may be employed according to application. The housing (see e.g. 112, 212, 312 of FIGS. 1-7) may be constructed of any suitable heat resistant material such as steel.
(17) As illustrated in FIG. 8, the temperature of each successive barrier panel, and of the air within each interstitial space or gap between adjacent panels, from the innermost (i.e. combustion barrier/first safety barrier) panel B1 to the outermost safety barrier panel Bx is higher than the preceding barrier panel. In other words, T1>T2>T3>Tx.
(18) Radiant energy emanating from the firebox opening (and conductive energy emanating from the combustion barrier) is converted into convection energy in ambient air being circulated through the safety barrier heat exchanger from an inlet “F in” associated with the outermost panel Bx to an outlet “F out” associated with the innermost panel B1 by at least one static or variable rate fan or blower, and is then supplied to the heated zone Zh (i.e. the room in which the heating appliance is situated, and/or another location via conventional ducting). For optimum heat exchange, the flow path through the first interstitial space (between panels B1 and B2) is vertically upwards, but alternate embodiments may involve a horizontal flow path in each interstitial space, a vertical downward flow path, or any combination of vertical and/or horizontal and/or diagonal flow paths.
(19) The location of fans and/or blowers within the safety barrier heat exchanger is determined according to application, and one or more additional fans or blowers may be used to boost air flow to a downstream ducted system. In some embodiments, ideal fan/blower location may be principally be predicated on sound attenuation principles and/or airflow efficiency and/or survivability of the fan/blower. The temperature at the outermost (i.e. “touch”) barrier panel Bx and temperature of the heated outlet air is controlled to be within limits set by certification standards, and to suit individual application requirements. In preferred embodiments, variable flow rate controllable fans or blowers may be utilized to maintain outermost barrier Bx temperature below a safe maximum during operation even when the fireplace system is operating at high burner combustion temperatures and serving as a heating appliance.
(20) The diagrammatical representation of the safety barrier heat exchanger in the attached Figures, including the spacing of barrier panels and configuration of brackets within which the barrier panels are held within the safety barrier heat exchanger, should not be interpreted as depicting any particular structural limitation, configuration, or spatial relationship of the various components shown, but instead is merely intended to illustrate various functional aspects of a safety barrier heat exchanger in accordance with various embodiments. The present description is of the best presently contemplated mode of carrying out the subject matter disclosed herein. The description is made for the purpose of illustrating the general principles of the subject matter and not to be taken in a limiting sense; the described subject matter can find utility in a variety of implementations without departing from the scope of the invention made, as will be apparent to those of skill in the art from an understanding of the principles that underlie the invention.
