The present disclosure relates to an apparatus for controlling the burn rate of solid fuel to prolong a flame-producing lifespan of the solid fuel.
Products such as decorative patio and garden torches and tabletop lanterns are known to burn alcohol-based gel or liquid fuel to produce an aesthetically-pleasing illuminating flame. In products of this type, the fuel is typically contained in a can having a lid that is difficult to reseal after opening. By design, the fuel can is intended for a single continuous use, and commonly lasts for about two hours once ignited. The use of gel or liquid fuel presents a safety hazard because the ignited fuel may spill and disperse across surfaces. For example, if a garden torch or table supporting a lantern is inadvertently bumped and fuel is spilled, the spilled fuel may spread the flame to persons, pets, or flammable objects.
It would be advantageous to use a solid fuel mass, such as an ethanol-based solid fuel mass, instead of a gel or liquid fuel. Ethanol-based solid fuel pellets are known for use as a fire-starter for campfires and the like. A solid fuel mass would improve safety by eliminating spillage risk, and would reduce waste by facilitating multiple intermittent uses with one fuel supply. However, a drawback weighing against replacing a gel or liquid fuel with an ethanol-based solid fuel mass is that the solid fuel mass exposed to surrounding air burns at a faster rate, thereby significantly decreasing the lifespan of the lantern or torch flame as compared to using a gel or liquid fuel.
Therefore, an apparatus for controlling the burn rate of a solid fuel mass is needed.
The present disclosure provides an apparatus in which a solid fuel mass is burned, wherein the burn rate of the solid fuel mass is controlled to slow the burning process and extend the lifespan of the solid fuel mass. According to an embodiment of the present disclosure, the apparatus comprises a base cup configured to receive a lower portion of the solid fuel mass, and a descent cup configured to receive an upper portion of the solid fuel mass, wherein the descent cup includes at least one flame orifice. The descent cup is telescopically associated with the base cup and moves toward the base cup as the solid fuel mass is burned, and a flame produced as the solid fuel mass is burned extends outwardly from each flame orifice of the descent cup.
The base cup may have an external cylindrical shape defined by an outer diameter, and the descent cup may have an internal cylindrical shape defined by an inner diameter greater than the outer diameter of the base cup. The descent cup may include a top wall for contacting the solid fuel mass. A flame orifice may be arranged to extend through the top wall of the descent cup. When a height of the solid fuel mass decreases to a level lower than a top rim of the base cup as the solid fuel mass is burned, the top wall of the descent cup may engage the top rim of the base cup such that the descent cup ceases moving toward the base cup. The apparatus may further comprise a housing containing the base cup and the descent cup.
The present disclosure also provides a method of burning a solid fuel mass. In an embodiment of the present disclosure, the method comprises placing a lower portion of the solid fuel mass in a base cup, placing a descent cup including a flame orifice over an upper portion of the solid fuel mass, igniting the solid fuel mass such that a flame extends outwardly from the flame orifice of the descent cup, and allowing the descent cup to descend toward the base cup as the solid fuel mass burns. The method may further comprise stopping the descent of the descent cup once a height of the solid fuel mass decreases to a level below a height of the base cup. The method may also comprise applying a vortex air flow to the flame.
The nature and mode of operation of the present disclosure will now be more fully described in the following detailed description taken with the accompanying drawing figures, in which:
Apparatus 10 generally comprises a base cup 20 configured to receive a lower portion of solid fuel mass SFM, and a descent cup 30 configured to receive an upper portion of the solid fuel mass. Descent cup 30 includes at least one flame orifice 32. As will be clear from description below, descent cup 30 is telescopically associated with base cup 20 and moves toward base cup 20 as solid fuel mass SFM is burned. As solid fuel mass SFM is burned, a flame produced by the burning fuel extends outwardly from flame orifice 32 of descent cup 30.
As illustrated in the drawing figures, base cup 20 may have an external cylindrical shape defined by an outer diameter 21 (see
Descent cup 30 may include a top wall 36 having an inner surface for contacting solid fuel mass SFM, and a sidewall 38 depending from top wall 36. Flame orifice 32 may extend through top wall 36 of descent cup 30. Alternatively, or additionally, flame orifice 32 and/or additional flame orifices (not shown) may extend through an upper region of sidewall 38.
Apparatus 10 may further comprise a housing 50 containing base cup 20 and descent cup 30. Housing 50 may include a base 60, a first wall portion 70 mounted on base 60 in a fixed position, and a second wall portion 80 mounted on base 60 for pivotal motion relative to first wall portion 70 between a closed position in which the first and second wall portions enclose the base cup and the descent cup (see
Base 60 may include a base platform 61, a first bracket assembly 62A on base platform 61 configured to removably hold first wall portion 70, and a second bracket assembly 62B on base platform 61 configured to removably hold second wall portion 80. Second bracket assembly 62B may be mounted on base platform 61 by a hinge 64 enabling second bracket assembly 62B to pivot relative to first bracket assembly 62A. Either first bracket assembly 62A or second bracket assembly 62B may include a magnet 65, and the other bracket assembly (second bracket assembly 62B or first bracket assembly 62A) may include ferrous material to which magnet 65 is attracted, whereby the first and second bracket assemblies 62A, 62B are biased toward holding the first and second wall portions 70, 80 in the closed position. Each bracket assembly 62A, 62B may include a brace member 67 and a clip plate 68 having a plurality of resiliently deflectable spring clips 69 configured to releasably hold an associated wall portion 70 or 80 against a surface of corresponding brace member 67. Base platform 61 may include a recess or opening 63 sized to receive depression 27 in bottom wall 26 of base cup 20, whereby base cup 20 may be removably positioned at a central location on base platform 61.
Apparatus 10 may further comprise a snuffer 90 which may include a handle portion 91 and an expanded portion 92 at a distal end of handle portion 91. Snuffer 90 is operable by a user to extinguish a flame by placing expanded portion 92 of snuffer 90 over flame orifice 32 of descent cup 30. As shown in the illustrated embodiment, base platform 61 may include a slot 66 configured to slidably receive at least the expanded portion 92 of snuffer 90 to conveniently store snuffer 90 when the snuffer is not in use. Slot 66 may be configured so that a handle portion 91 of snuffer 90 protrudes from base platform 61 when snuffer 90 is stored in slot 66.
Reference is made now to
As may be seen in
Finally,
The provision of descent cup 30 advantageously slows the rate at which solid fuel mass SFM burns off, thereby causing flame F to last longer. In experiments conducted by applicant, a solid fuel mass lasted about forty-five minutes without the use of descent cup 30, but an equivalent solid fuel mass lasted about three hours with the use of descent cup 30.
While the disclosure describes various exemplary embodiments, the detailed description is not intended to limit the scope of the disclosure to the particular forms set forth. The disclosure is intended to cover such alternatives, modifications and equivalents of the described embodiment as may be apparent to one of ordinary skill in the art.