Patent Application
20050227194
Not Applicable
Not Applicable
Not Applicable
This invention is for a fireplace fuel cartridge, primarily for use in ventless fireplaces although usable in vented fireplaces as well, where the fuel cartridge self regulates the shape, height, width, depth and burn time of the flames produced when the fuel in the cartridge, such as alcohol gel, is ignited, thereby producing a desirable, generally rectangular flame pattern that makes efficient use of fuel, and where the cartridge accomplishes this without a need for additional components such as rectangular holding boxes or damper lids.
Ventless fireplaces are very popular. Such fireplaces are easy to install because they do not require chimneys or exhaust systems.
There are two main types of ventless fireplaces. The first type uses gas that is piped into the fireplace. The gas is burned by a type of burner that does not produce appreciable noxious fumes. Typically, such burners provide generally rectangular flame patterns wider than they are deep.
Generally rectangular flame patterns are common to many fireplaces, both vented and ventless. Indeed, the flame pattern in almost all fireplaces is wider than it is deep. Fireplace logs are generally wider than they are deep and many consumers expect fireplace fires to exhibit a generally rectangular flame pattern.
Aside from gas, the second type of ventless fireplace in common use uses a clean burning portable fuel source, typically alcohol gel fuel. Such an alcohol gel is described, for example, in U.S. Pat. No. 4,575,379 to Browning.
Alcohol gel, however, is typically purchased in small round cans that resemble paint cans. These cans usually hold about one pint of fuel, or a little less. Similar to the cans themselves, the lid openings on the cans are also round.
When this “paint can” type canister of alcohol gel fuel is placed inside a fireplace, and the round lid is removed from the round lid opening on top of the can, and the exposed fuel is ignited, a generally round flame is produced.
As discussed previously, however, fireplace flame patterns are generally rectangular, not round. “Paint can” type canisters, therefore, are inherently problematic when used to hold fireplace fuel, because they are not designed to produce a rectangular flame pattern.
In addition, paint cans cannot shape and regulate the width, depth or number of flames that are produced when the fuel inside an individual can is ignited.
Because “paint can” type fuel containers do not have the ability to shape, regulate or control a rectangular flame pattern, inventors have been forced to create other methods for shaping and controlling the flames paint cans produce.
For example, U.S. Pat. No. 4,838,781 to Fischer, discusses a ventless fireplace that uses such cans. The cans are referred to as “cans of gelled fuel” at Col. 5, line 28. Component 31 in
In order to obtain a flame pattern approximating a rectangularly shaped flame pattern Fischer teaches placing a series of round cans in a straight line, and placing the cans in a rectangular receptacle called a “fuel cell”. (See claim 1b of the Fischer patent.)
Fischer's rectangular receptacle is also equipped with a rectangular damper lid which the patent states is used to regulate “the burning rate” of the fuel and can “dampen” same.
The rectangular receptacle and rectangular damper lid re-shape the configuration of the round fires produced by the “paint cans” so as to produce a quasi-rectangular flame pattern whose width is greater than its depth.
The problems that “paint cans” present when they are used to hold fireplace fuel have been addressed by other inventors, aside from Fischer. For example, Myers also dealt with these problems in U.S. Pat. No. 4,573,905. This patent is also for a ventless alcohol fireplace that uses “standard one-pint size” canisters shown to be round, as component 194 of FIG. 1 of the Myers' patent illustrates.
Similar to Fisher, Myers attempted to solve this problem by using multiple canisters, placed in a straight line. Also similar to Fisher, Myers specifically required the cans to be placed in a rectangular metal box called a “fuel cell”. Myer's “fuel cell” holds three cans.
It is inherently inconvenient, inefficient and ineffective, however, to try to achieve a quasi-rectangular flame pattern by placing a series of round “paint cans” next to one another, in a straight line.
For one thing, it requires the use of multiple cans.
For another, it may require the use of rectangular metal receptacles called “fuel cells” to hold the cans, as the Fischer and Myers patents show.
A third problem is that the rectangular “fuel cells” may also require rectangular damper lids to further shape the fire and regulate the burn rate.
A fourth problem is that several round “paint cans”, even when placed in a line, do not produce a truly rectangular flame pattern. A truly rectangular flame pattern cannot be achieved no matter how many round cans are used.
A fifth problem is that there will be gaps in the “quasi-rectangular” flame pattern produced by a series of round “paint cans.” Gaps will exist where the outside perimeter of one can touches the outside perimeter of the adjacent can, as shown in the
A sixth problem relates to fuel efficiency. Using “paint cans” to achieve a quasi-rectangular flame pattern is inherently inefficient. It burns more fuel than should be required in order to achieve a somewhat rectangular flame pattern, which it cannot truly do in any event.
For example, if a 10″ by 1.25″ rectangular flame is desired, this result can be achieved by the current invention by using a rectangular fuel cartridge with a rectangular opening on its top that measures 10″×1.25″.
Hence, the current invention achieves a 10″×1.25″ rectangular flame pattern by exposing a total of 12.25 square inches of alcohol gel fuel to ambient air, which gel may then be ignited and burned.
“Paint cans”, however, expose much more fuel to ambient air in order to attempt to achieve a 10″ wide flame pattern.
For example, using “paint cans” with 4″ diameters and 3.33″ openings, placing three cans in a line will produce a flame pattern that is arguably 10″ wide, with gaps, but because each can exposes and burns about 8.7 square inches of fuel, total fuel exposure is approximately 26.1 square inches. This is more than double the 12.25 square inches the current invention requires.
Hence, “paint cans” waste fuel. In this example they expose and burn over 210% more fuel than the current invention, and they still do not produce a truly rectangular flame pattern.
For all these reasons round “paint cans” should not be used to hold alcohol gel fuel intended for use in fireplaces. Rather, it would be much more convenient to fashion a generally rectangular disposable fuel cartridge specifically designed for use in a fireplace, which cartridge has a generally rectangular opening exposing the fuel, and where the opening was specifically designed to self regulate the shape, height, width and depth of the generally rectangular flame pattern produced by the cartridge, as well as the fuel burn rate.
The present invention accomplishes that result.
The applicant is unaware of any disposable, ventless fireplace gel fuel cartridge sold on the market which self regulates the width and depth of the flame the cartridge produces, so as to create a rectangular flame pattern.
Instead, the prior art utilizes multiple “paint can” type gel fuel canisters. Although one may attempt to obtain a rectangular flame pattern by placing multiple canisters in a straight line, there are inherent disadvantages to this practice.
First it requires the use of multiple canisters versus a single fuel cartridge specifically designed to produce a rectangular flame pattern.
Second, it may require the use of a rectangular metal receptacle called a fuel cell to hold the multiple “paint can” type canisters.
Third, it may also require the use of a rectangular damper lid on top of the rectangular fuel cell, as the prior art discusses.
Fourth, round “paint cans”, even when placed next to one another in a line, will produce gaps in the flame pattern, as shown in
Fifth, “paint cans” are inherently fuel inefficient when used for fireplace fires. They expose more fuel to ambient air than required in order to achieve a desirable rectangular flame pattern.
Sixth, the openings in “paint cans” are not specifically designed to self regulate the size of fireplace flames. Instead, the “paint cans” used in the prior art appear to be just that, paint cans. As the prior art reveals, the paint cans require the use of a rectangular damper lid over a rectangular metal “fuel cell” box to regulate the size of the flames produced.
Seventh, round “paint cans” are inherently inefficient from a storage point of view. They require more cubic inches to store than the rectangular cartridges embodied by the present invention.
The objects and advantages of the invention described herein are:
(a) provide a convenient, one piece, disposable fuel cartridge whose configuration is generally rectangular, and which has a generally rectangular opening on its top, so as to produce a rectangular type flame pattern when the fuel inside is ignited.
(b) to provide a convenient, one piece, disposable fuel cartridge whose configuration burns fuel efficiently and requires less fuel than multiple “paint cans” require to produce a generally rectangular flame pattern.
(c) to provide a convenient, one piece, disposable fuel cartridge whose generally rectangular configuration and generally rectangular top opening produces a self regulating rectangular type flame pattern that does not require the use of a damper or a valve.
(d) to provide a convenient, one piece, disposable fuel cartridge whose configuration allows for efficient storage compared to round “paint cans”.
In accordance with the present invention a disposable fuel cartridge for use in fireplaces that self regulates the shape, height, width, depth and burn time of the flames produced when the fuel inside the cartridge, such as alcohol gel, is exposed to ambient air and ignited, so as to produce a desirable, generally rectangular flame pattern without the need for any additional components, such as metal “fuel cell boxes”, and where the cartridge makes efficient use of fuel as well as efficient use of storage space.
The presently preferred embodiment of the invention is illustrated in the figures.
The fuel cartridge 10 consists of a front wall 13, a back wall 18, sidewalls 11 and 14, front and back vapor restrictors 15a, left and right vapor restrictors 15b, and a rigid lid 17. When the rigid lid 17 is removed a vapor exit aperture 16 is created which exposes the fuel 16A to ambient oxygen.
All four vapor restrictors 15a-b, together, create a rectangular vapor exit aperture 16. This creates a generally rectangular flame pattern 20.
In addition, by restricting and controlling vapor flow the vapor restrictors 15a-b also allow the fuel cartridge 10 to self regulate the flow of vapor, the size of the fire 20, and the burn time of the fuel cartridge 10, all without the need for the items discussed in the prior art, such as a rectangular “fuel cell” or a rectangular “damper”.
The vapor restrictors 15a-b restrict vapor flow in two ways. First, they restrict the flow of flammable vapors that can sublimate from the fuel 15c that is immediately below the vapor restrictors 15a-b. Second, the vapor restrictors 15a-b restrict the flow of ambient oxygen into the fuel cartridge 10, including the area 15d immediately below the vapor restrictors 15a-b.
Assuming one size of fuel cartridge 10 for comparison purposes, larger front and back vapor restrictors 15a will create a vapor exit aperture 16 with less depth. For example, on a fuel cartridge 10 with a total depth of 2.5 inches, front and back vapor restrictors 15a that are each 0.5 inches in depth will create a vapor exit aperture 16 that is 1.5 inches deep. In turn, this will create a flame pattern 20 that is also approximately 1.5 inches deep.
On that same fuel cartridge 10, if the front and back flame restrictors 15a-b are each 0.75 inches deep, the vapor exit aperture 16 will only be 1.0 inches deep, which will result in a flame pattern of approximately the same depth.
Similarly, the size of the left and right flame restrictors 15b control the length of the vapor exit aperture 16. For example, on a fuel cartridge 10 with a ten inch length, left and right vapor restrictors 15b that are each 0.5 inches will create a vapor exit aperture 16 that is 9.0 inches long. On that same fuel cartridge 10, left and right vapor restrictors 15b that are each 1.0 inches will create a vapor exit aperture 16 that is 8.0 inches long.
As a general principle, on a given size of fuel cartridge 10, larger flame restrictors 15a-b will result in smaller flames and a longer burn time. Smaller vapor restrictors 15a-b will result in larger flames and a shorter burn time.
By varying the length, width and depth of the rectangularly shaped fuel cartridge 10, and by varying the size of the vapor restrictors 15a-b, and thereby the flame exit aperture 16, the fuel cartridge 10 can be made to self regulate, so as to produce a larger or smaller fire 20 that can burn for longer or shorter periods of time.
Operation
To operate the fuel cartridge in accordance with the present invention one removes the lid 17 from the fuel cartridge 10 thereby exposing the alcohol gel fuel 16 which is then ignited. A rectangular flame pattern 20 will result.
Alternative Embodiments
Variations in the length, width and depth of the rectangularly shaped fuel cartridge 10, and the size of the vapor restrictors 15a-b, will produce a larger or smaller fire 20 that can burn for longer or shorter periods of time. For example, one hour, two hour, or three hour fires 20 are possible, which fires 20 can have larger or smaller flames.
Various methods of sealing the fuel cartridges 10 may be employed, such as rigid friction lids 17 or a removable film or tape like covering 17A. Many other alternative methods of sealing the fuel cartridge 10 also exist, such as using “easy off” scored metal tops similar to those found on sardine or soda cans.
Additionally, the fuel cartridge 10 and/or the vapor restrictors 15a-b may be manufactured out of extremely thin metal foil. And, as
Both the fuel cartridge 10 and vapor exit aperture 16 do not have to be exact rectangles in order to have widths substantially greater than their depths. Any shape whose width is substantially greater than its depth, as shown in
Thus, the scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the specific descriptions of the exemplar fuel cartridge illustrated in the figures.
Advantages of the Present Invention
From the description above, a number of advantages of the present invention become evident:
(a) the invention provides a convenient, one piece, disposable fuel cartridge which produces a desirable rectangular flame pattern when the fuel inside is ignited.
(b) the invention provides a convenient, one piece, disposable fuel cartridge which burns fuel efficiently and requires less fuel than multiple “paint cans” require to produce a rectangular flame pattern, which paint cans cannot do.
(c) the invention provides a convenient, one piece, disposable fuel cartridge that produces a self regulating rectangular flame pattern that does not require the use of additional components mentioned in the prior art, such as a rectangular box “fuel cell” or a rectangular damper lid on top of the “fuel cell”.
(d) the invention provides a convenient, one piece, disposable fuel cartridge whose configuration allows for efficient storage compared to round “paint cans”.
