REFERENCE REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable
SEQUENTIAL LISTING
Not applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to candleholders.
2. Description of the Background of the Invention
Many different assemblies for holding a candle are known. In one candle assembly, a wicked candle is disposed inside a cylindrical container having a recessed stepped ring encircling an open top end thereof. A circular shade body fits within the open top end and has an outer peripheral flange that rests on the recessed stepped ring.
Another candleholder includes a standard for receiving a candlestick, which extends from a base of the candleholder. The standard has a socket with an out-turned flange at an upper end thereof for receiving the candlestick therein. A funneled split tube is disposed in the socket. The split tube has an out-turned peripheral flange that rests on the out-turned flange of the socket. A cap spans the out-turned flange of the socket and rests on a peripheral edge thereof spaced above the split tube.
An electric candle is known that has a hollow cylindrical body portion extending up from a mounting base. A votive candle is carried within an open upper end of the body portion by a bracket having a plurality of arms extending radially outwardly from a central frustoconical rim. The votive is carried inside the rim, and the peripheral edges of the arms rest on a recessed inner annular rim at the open upper end of the body portion.
A candle having a constant elevation flame includes a wax body contained within a tubular outer casing. A spring urges the wax body upwardly toward a wick carried over an open end of the outer casing by a thermally-insulated cover. The wick extends through a central aperture in the cover and is retained at a constant elevational position by a wire. An outturned peripheral lip of the cover rests in a peripheral recess in the tubular casing.
SUMMARY OF THE INVENTION
According to one aspect of the invention, a candleholder for carrying a fuel element thereon includes a base portion having a sidewall defining a recess at a top end of the base portion and a shoulder spaced from the top end projecting from the wall within the recess. A melting plate adapted to retain the fuel element is disposed within the recess. The melting plate has a peripheral edge and a ledge spaced from the peripheral edge defined in a bottom surface of the plate. The ledge engages the shoulder.
According to another aspect of the invention, a candleholder includes a base portion and a melting plate. The base portion includes a recess in an upper end thereof. The recess is defined by a peripheral inner wall surface and a bottom wall surface. A shoulder protrudes from the peripheral inner wall surface, and a ring protrudes from the bottom wall surface. The melting plate includes a bottom central wall portion surrounded by an upturned peripheral wall portion, a ledge defined in a bottom surface of the upturned peripheral wall portion, and a cavity defined in the bottom surface of the central wall portion. The ledge is spaced from a peripheral edge of the melting plate. The melting plate is disposed in the recess with the ledge disposed on the shoulder and the ring disposed inside the cavity.
In yet another aspect of the present invention, a candleholder includes a base portion having a recess for supporting a concave melting plate therein and an alignment mechanism to align the melting plate in the recess in a pre-selected spaced relationship to a portion of the base portion.
Other aspects and advantages of the present invention will become apparent upon consideration of the figures and the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded isometric view of a candle assembly according to one aspect of the present invention;
FIG. 2 is an enlarged isometric view of a wick holder shown in FIG. 1;
FIG. 3 is a cross-sectional view of a fuel element along the line 3-3 of FIG. 1;
FIG. 4 is a cross-sectional view generally transverse to line 3-3 of FIG. 1 with the candle assembly in assembled form;
FIG. 5 is an enlarged partial cross-sectional view along the line 5-5 of FIG. 4;
FIG. 6 is an enlarged isometric view of a wick holder and a portion of a melting plate according to yet another aspect of the invention;
FIG. 7 is an isometric view of still another wick holder according to the present invention;
FIG. 8 is an enlarged cross-sectional view of the wick holder shown in FIG. 7 in a similar view as shown in FIG. 5;
FIG. 9 is an isometric view of a candleholder according to another aspect of the present invention;
FIG. 10 is an exploded isometric view of a candleholder according to a further aspect of the present invention; and
FIG. 11 is an exploded cross-sectional view of the candleholder of FIG. 10 along a vertical plane at a centerline thereof.
DETAILED DESCRIPTION
Referring now to FIGS. 1-5, a candle assembly 100 includes a support base 102, a melting plate 104, a wick holder 106, a wick 108, and a fuel element 110. The support base 102 carries the melting plate 104, which is generally saucer shaped, and includes a centrally disposed capillary pedestal 112. Optional decorative etchings 114 are disposed on an upper exposed surface of the melting plate 104 to provide enhanced attractiveness or visual information. The wick holder 106 includes a base portion 116 that fits over the capillary pedestal 112, a wick retainer sleeve in the shape of an elongate cylindrical barrel 118, and heat conductive elements, such as fins 120. The barrel 118 receives the wick 108 therein such that the wick extends from the base portion 116 with a portion of the wick exposed above the barrel. The fuel element 110 is disposed over and around the wick holder 106 and includes a duct or slot 122 through which the wick 108 extends. The slot 122 has a width w1 sufficient to allow the wick 108 to extend through the slot and a length l1 sufficient to accept at least a portion of the fins 120 therethrough. In one embodiment, the fuel element 110 has a mass of wax approximately 15 grams, and the melting plate candle 100 burns continuously between about 3 and 3½ hours on a single fuel element, such as the wax fuel element 110, before the fuel is completely consumed.
As seen in FIG. 2, the base portion 116 of the wick holder 106 includes an end plate 124 encompassed by a generally conical base skirt 126, and an upper portion including the barrel 118 extending upwardly from the base skirt and the fins 120 extending from the barrel and end plate 124. The base portion 116 is adapted to fit closely over and around the capillary pedestal 112 such that the barrel 118 is maintained in an upright, or substantially vertical, orientation when placed on the capillary pedestal. The base skirt 126 includes indentations or spacers 128, and holes 130 extend through the end plate 124. Ferromagnetic structures, such as steel rivets 132 or magnets (not shown), are secured to the base portion 116, such as through the holes 130, so that the wick holder 106 may be releasably secured over the capillary pedestal 130 by magnetic forces. The barrel 118 is sized to receive the wick 108 with either a close fit or interference fit so as to retain the wick therein and defines an opening 134 in the end plate 124 such that the wick can extend through the end plate. The fins 120 extend laterally outwardly on opposite sides of the barrel 118 and extend upwardly above the barrel. In one embodiment, the fins 120 are shaped to simulate a flame outline. In other embodiments, the fins 120 may have square, circular, oval, triangular, or other non-geometric shapes, and in still other embodiments, the fins 120 may have insulated areas (not shown) as described more fully in U.S. patent application Ser. No. 10/939,039, filed Sep. 10, 2004, and incorporated herein by reference in its entirety. The fins 120 are relatively thin strips of heat conductive material, such as metal, for transmitting heat from a flame burning on the wick 108 outwardly toward the fuel element 110. In one embodiment, the wick holder 106 is formed from a single sheet of aluminum that is cut and folded about a fold 136 and thereby forming a capillary space 138 between opposite sides 140 and 142 and channels or gaps 144 in the base skirt 126. In other embodiments, the wick holder 106 may be formed by other methods from other heat resistant materials, such as ceramic, other metals, heat resistant plastics, etc. If the wick holder 106 is formed of a ferromagnetic material, such as steel, the steel rivets 132 may optionally be omitted. The two sides 140 and 142 are secured together by any convenient means, such as with rivets 146 through holes 148 in the heat fins 120, welds, clips, heat resistant adhesives, etc. The gaps 144 and the holes 130 allow melted fuel material from the fuel element 110, to drip or seep underneath the base skirt 126, and the capillary space 138 allows melted fuel material to traverse up the fins 120 by capillary action and thereby provide a source of fuel material in non-consumable wick areas 150. An example of such capillary action is described in U.S. patent application Ser. No. 10/938,453, filed Sep. 10, 2004, and incorporated herein by reference in its entirety.
As seen in detail in FIG. 3, the fuel element 110 includes a body 152 of fuel material and has an upper surface 154 and a lower surface 156. The fuel element 110 in one embodiment is a wax puck and in other embodiments may have other shapes and include other meltable or flowable fuel materials, such as paraffin or animal fat, having a solid or semi-solid state or otherwise maintainable in a fixed form at room temperature. The lower surface 156 of the fuel element 110 defines a cavity 158 having an upper cavity wall 160 shaped to conform closely to the base portion 116 of the wick holder 106. The slot 122 extends from the upper surface 154 to the cavity wall 160 and has a width w1 at the upper surface that is smaller than a width w2 at the cavity wall. The width w1 is adapted to prevent melted wax from the fuel element 110 from falling or trickling down the slot 122 without engaging the wick 108, or put another way, the width w1 is narrow enough to ensure that melted fuel material from near the upper portion of the slot 122 will engage the wick 108 as it falls or trickles down the slot. In one embodiment, w1 is not more than approximately 0.02″ (0.5 mm) larger than a diameter of the wick at an upper end of the slot 122. In another embodiment, w1 is approximately the same as a diameter of the wick 108. In yet another embodiment, the width w1 is less than a width of the wick 108 so that an interference fit exists between the wick and the body 152 at the upper end of the slot 122. In a further embodiment, the width w1 is less than or equal to approximately 0.12″ (3 mm), and the wick 108 has a diameter of approximately 0.1″ (2.5 mm). In yet a further embodiment (not shown), the slot 122 may have a width that is initially more than 0.02″ (0.5 mm) larger than a diameter of the wick 108 to allow for easy insertion of the wick 108 and wick holder 106 into the slot 122, and the slot is filled subsequently with additional fuel material in a second manufacturing step so that the width w1 is less than 0.02″ (0.5 mm) larger than the diameter of the wick.
As shown in FIG. 4, the support base 102 carries the melting plate 104 within an upper chamber 162, which is generally bowl-shaped. The melting plate 104 in one embodiment is secured to a sidewall 164 of the upper chamber 162 with adhesive 166 thereby providing an empty air space 168 between the melting plate and an intermediate wall 170 of the support base 102. The air space 168 provides additional insulation between the melting plate and the support base 102 to reduce heat loss through the melting plate to the support base. In another embodiment (not shown) the melting plate 104 is adjacent to the intermediate wall 170 with adhesive 166 placed therebetween such that no air space 168 is disposed between melting plate and the intermediate wall. Of course, other arrangements and support configurations for the melting plate 104 are also suitable for supporting the melting plate 104.
In one embodiment of the fuel element 110, the slot 122 has a length l1 in the upper surface 154 that is longer than a length l2 in the lower surface 156. The length l1 is shorter than a largest width wf of the fins 120 and the length l2 is longer than the largest width wf of the heat fins. Such a configuration of the slot lengths l1 and length l2 in relation to wf, in addition to the slot widths w1 and w2 as described herein above, facilitates inserting the wick holder 106 fully into the slot from the lower surface 156. Such configuration of the slot 122 and cavity 158 also prevents the slot from fully receiving the wick holder if the fins 120 are inserted into the slot through the upper surface 154 rather than through the lower surface 156, thereby preventing or discouraging improper assembly of the fuel element 110 and the wick holder 106.
As illustrated in FIG. 5, a portion of the melting plate 104, capillary pedestal 112, wick holder 106, fuel element 110, and wick 108 are shown assembled and ready for use or initial ignition by a user. In one embodiment, the capillary pedestal 112 includes an inclined sidewall 172 having an annular groove 174 extending therearound in a medial position between a floor 176 of the melting plate 104 and a top wall 178 of the capillary pedestal. A magnet 180 is secured to an underside of the top wall 166 with adhesive 182. In another embodiment, the magnet 180 may be disposed on an upper side of the top wall 178 or at another location sufficient to attract the wick holder 106. The spacers 128 are adapted to seat in the annular groove 174 to provide a capillary space 184 between the base skirt 126 and the inclined sidewall 172 sized to facilitate capillary movement of melted or liquid fuel material toward the wick 108. The spacers 128 also help retain the wick holder 106 on the capillary pedestal 112 by seating in the annular groove 174. In addition, the steel rivet 132 in the wick holder 106 is attracted to the magnet 186 when placed over the capillary pedestal 112 and thereby prevents the wick holder from accidentally falling or slipping off of the capillary pedestal. When placed on an underside of the end plate 124, the steel rivets 132 also act as spacers to help maintain the capillary space 184. In another embodiment, magnets 186 may be secured to the end plate 124 by any convenient means, such as with an adhesive or by a rivet, in order to maintain the wick clip 106 in position on the capillary pedestal 112. The cavity wall 160 of the fuel element 110 is shaped to closely fit around the base skirt 126 and barrel 118 of the wick holder 106 and rest on the floor 176 of the melting plate in order to minimize open space 188 between the fuel element and the wick 108, the wick holder 106, and the melting plate floor 176. Minimizing the open space 188 increases the likelihood of having melted fuel material being fed directly to the wick 108 rather than falling downwardly to the floor 176 or accumulating in the open space and thereby potentially starving the wick of fuel material while burning. However, as melted liquid fuel material accumulates about the base of the capillary pedestal, whether due to melting from the melting plate 104 or from direct melting by a flame on the wick 108, the liquid fuel material is drawn upwardly along the capillary space 184 by capillary action toward the non-consumable wick areas 150 while the candle is burning. The wick 108 in one embodiment extends through the open end 134 of the barrel 118 to touch or nearly touch the top wall 178 of the capillary pedestal 112 so that liquid fuel material drawn up the capillary space 184 will engage the wick 108 and be drawn upwardly therein for eventual burning by a flame burning atop the wick. The wick barrel 118 has an inside diameter sufficient to receive the wick 108. The inside diameter of the barrel 118 may be larger, smaller, or the same as the diameter of the wick and may be uniform or have different diameters along a length thereof. In one embodiment, the inside diameter of the barrel 118 is larger than the diameter of the wick 108 so that the wick may be easily inserted into the barrel. In another embodiment, the inside diameter of the barrel 118 is uniformly approximately 0.012″ (0.3 mm) larger than the diameter of the wick 108. In yet other embodiments, the inside diameter of the barrel 118 is the same size as or smaller than the wick 108. Melted fuel material can seep into the capillary space 184 through the weep holes 130 and thereby prime or facilitate capillary action upward through the capillary space 184. Liquid fuel material may also be drawn upwardly in the capillary space 138 between opposing sides 140, 142 of the fins 120 and drawn to the non-combustible wick areas 150 where the fuel material may be vaporized and ignited by a flame on the wick 108.
Turning now to FIG. 6, another wick holder 200 and melting plate 202 are shown that are similar to the wick holder 106 and melting plate 104 shown in FIGS. 1-5, except that a capillary pedestal 204 includes a smooth inclined sidewall 206 without the annular groove 174, and the wick holder 200 does not include the spacers 128 in the base skirt 126. A capillary space (not shown), similar to 184, is maintained between the base skirt 126 and the sidewall 206 by steel rivets 132 protruding below an end wall, such as 124, of a base portion 116 of the wick holder 200. In this embodiment, the wick holder 200 is maintained on the capillary pedestal 204 substantially by the attraction between the steel rivets 132 and magnet 180 (not shown in FIG. 6) in the capillary pedestal and any weight of the fuel element 110.
Turning to FIGS. 7 and 8, a wick holder 300 of another embodiment for use in a candle assembly, such as 100, is similar to the wick holder 106 (or 200) except that the wick holder 300 also includes a medial portion of the barrel 118 having a cross-sectional area that is less than a cross-sectional area of any other portion of the wick barrel. An indentation 302 in a sidewall 304 of the barrel 118 defines a constricted portion 306 of the barrel located or disposed intermediate opposite ends 308 and 310 of the barrel and having a cross-sectional area less than any other portion of the barrel. The wick 108 extends through the barrel 118 such that a portion or end of the wick adapted to absorb melted or fluid fuel material extends downwardly through the end 310 and another portion or end of the wick adapted for ignition extends upwardly through end 308. The constricted portion 306 reduces an effective wick cross-sectional area, and thereby may reduce or restrict a capillary fluid flow capacity of the wick between the first open end and the second open end. The restricted flow capacity, and subsequently reduced volume flow rate, of fluid fuel material up the wick from end 310 toward a flame region above end 308, in turn may reduce the fuel material burn rate and extend the life of the fuel element 110. Because the constricted portion 306 having a larger cross-sectional area allows a faster volume flow rate, or increased capillary fluid flow capacity, than a constricted portion having a smaller cross-sectional area, the capillary fluid flow capacity of the wick may be substantially reduced by reducing the cross-sectional area of the constricted portion. Such a constriction on the flow rate of fuel material upwardly along the wick 108 past the constricted portion 306 is enhanced when the sidewall 304 is substantially liquid impervious (e.g., does not allow fuel material to pass therethrough to the wick 108) which thereby restricts the flow of fuel material into the wick to coming only through the end 310 located in the end plate 124 or above the end 308 of the barrel 118. The indentation 302 may also help maintain the wick 108 in a predetermined position within the barrel 118 such that, for example, an end portion of the wick extends through or to the end 310 in order to prevent the wick from being pulled out of the barrel and thus potentially losing contact with the flow of fuel material toward the wick through the capillary space 184 and weep holes 130.
Other variations and embodiments of the candle assembly and wick holder 300 described in detail herein are also specifically contemplated. For example, in one embodiment, the barrel 118 may take the form of a sleeve having a cylindrical shape or a tubular shape having other cross-sectional areas and shapes. In another embodiment, the constricted portion 306 in the barrel 118 is formed by an inner annular ridge (not shown), which may be formed by indenting or crimping the sidewall 304 entirely around the wick barrel 118 or by an inner annular shoulder disposed on an inner surface of the sidewall 304. The constricted portion 306 in another embodiment may be formed by a single indentation 302 or by a plurality of indentations, which may be either in opposing relationship or offset from each other. In another embodiment (not shown) the barrel 118 may have form of a wick casing that is not generally tubular, but rather includes a longitudinally curved sidewall that encases a portion of the wick 108 and has first and second openings in the sidewall through which the wick extends.
In another aspect of the present invention, which is shown in FIG. 8 but which is also applicable to any combination of any of the capillary pedestals and any of the capillary pedestals described herein, the capillary space 184 defines a volume, or capillary well 350, between the base portion 116 of the wick holder 300 and the capillary pedestal 204 that has a dimension preselected to promote a successful sustained relight of the wick 108 after a pool 352 (shown in dashed lines) of wax or other meltable fuel has been formed in melting plate 202 around the peripheral skirt 126 and capillary pedestal and then allowed to solidify. During a sustained burn, liquefied wax from the pool 352 is drawn into the capillary well 350 and up to the wick 108 by capillary action to feed a flame 354 at wick 108. If the flame 354 is extinguished prior to consuming the entire fuel element 110, the pool 352 of wax solidifies and extends across the bottom of the melting plate 202, through the capillary well 350, and into the wick 108. In one embodiment, when the wick 108 is re-lit after the pool 352 of wax has solidified, the capillary space 184 is dimensioned such that a supply of liquefied wax is quickly formed and available in the capillary well 350 to feed the flame 354 via the wick 108 until the wax surrounding the peripheral skirt 126 has melted sufficiently to provide a supply of liquefied fuel to replace the wax in the capillary well. For example, if the capillary space 184 is dimensioned too small, there may not be enough wax in the capillary well 350 to sustain the flame 354 on the wick 108 during a sustained relight before the wax pool 352 surrounding the peripheral skirt 126 has melted enough to provide additional liquefied fuel to the wick 108. Also for example, if the capillary space 184 is too large, heat transfer through the solidified wax in the capillary well 350 may be too slow to melt enough of the wax therein to provide liquefied fuel to the wick 108 before wax in the wick is burned. Under either circumstance, the flame 354 may run out of fuel and extinguish prior to melting a sufficient amount of wax in the pool 352 to begin or sustain substantially continuous capillary movement of the melted wax from outside of the capillary space 184, into the capillary well 350, and up the wick 108 to feed the flame 354. Therefore, to assist in a successful sustained relight of the wick 108 in one embodiment, the capillary well 350 has a volume not less than a volume sufficient to provide melted fuel to the relit wick 108 until a sufficient amount of liquefied fuel is formed from the pool 352 of solidified wax adjacent to or surrounding the peripheral skirt 126 to continuously feed the flame 354 by capillary action through the capillary space 184, and in another embodiment, the volume of the capillary well 350 is not more than a volume able to allow heat from the flame 354 to melt the solidified fuel disposed in the capillary space 184 sufficiently rapidly to feed the flame 354 after solidified fuel carried in the wick is burned. In a further embodiment, a successful relight can be achieved if the volume of the capillary well 350 is proportional to a thermal mass of an entire candle assembly, such as 100, in order to provide a sufficient source of melted fuel to the wick until the pool 352 of solidified wax has melted sufficiently to provide an adequate flow of fuel to the wick 108 to maintain a sustained burn of the flame 354. The thermal mass of the candle assembly 100 is a measure of the amount of energy needed to change the temperature of the entire melting plate candle by a measured amount and is equal to the sum of the products of the mass of each portion of the candle assembly multiplied by the specific heat of that portion. According to one aspect, the volume of the capillary well 350 is between about 0.00006 cubic inches per calorie per degree centigrade (hereinafter, in3/cal/° C.) (1 mm3/cal/° C.) and about 0.0006 in3/cal/° C. (10 mm3/cal/° C.), or between about 0.0001 in3/cal/° C. (2 mm3/cal/° C.) and about 0.0004 in3/cal/° C. (6 mm3/cal/° C.), or between about 0.00018 in3/cal/° C. (3 mm3/cal/° C.) and about 0.00024 in3/cal/° C. (4 mm3/cal/° C.). Accordingly, in one embodiment, the thermal mass of the candle assembly is between about 135 cal/° C. and 10 cal/° C., or between about 75 cal/° C. and 40 cal/° C., or between about 61 cal/° C. and about 50 cal/° C., and the volume of the capillary well 350 is between about 0.006 in3 (100 mm3) and about 0.03 in3 (500 mm3), or between about 0.009 in3 (150 mm3) and 0.018 in3 (300 mm3), or about 0.012 in3 (200 mm3).
For example, the thermal mass of an embodiment of a candle assembly, such as 100, includes the support base 102, the melting plate 202, and the wick holder 300 having a combined thermal mass of about 50 cal/° C. and the fuel element 110 of approximately 0.53 oz. (15 g) of wax having a thermal mass of about 10.5 cal/° C. before being burned. The capillary pedestal 204 has a generally frustoconical shape with a height h1 between about 0.39″ (10 mm) and 0.04″ (1 mm), or about 0.2″ (5 mm), a bottom radius Φ1 between about 1.18″ (30 mm) and 0.39″ (10 mm), or about 0.83″ (21 mm), and a top radius Φ2 between about 0.04″ (1 mm) and 0.79″ (20 mm), or about 0.43″ (11 mm). The base 116 has a frustoconical shape generally complementary to the capillary pedestal with the peripheral skirt 126 having an upper diameter Φ3 of between about 0.08″ (2 mm) and about 0.83″ (21 mm), or between about 0.43″ (11 mm) and about 0.55″ (14 mm), or about 0.51″ (13 mm); a bottom diameter Φ4 between about 1.22″ (31 mm) and about 0.43″ (11 mm), or about 0.79″ (20 mm) and about 0.91″ (23 mm), or about 0.87″ (22 mm); a height h2 between about 0.43″ (11 mm) and 0.08″ (2 mm), or between about 0.28″ (7 mm) and about 0.16″ (4 mm), or about 0.2″ (5 mm); and a height h3 of the rivets 132 from the end plate 124 of between about 0.004″ (0.1 mm) and 0.04″ (1 mm), or between about 0.03″ (0.8 mm) and about 0.02″ (0.5 mm), or about 0.02″ (0.6 mm). In another embodiment, the capillary pedestal 204 has a height h1 about 0.18″ (4.7 mm), a bottom radius Φ1 about 0.81″ (20.5 mm), a top radius Φ2 about 0.44″ (11.1 mm), and the base 126 has a skirt 126 having an upper diameter Φ3 about 0.5″ (12.6 mm), a bottom diameter Φ4 about 0.85″ (21.6 mm), and a height h2 about 0.2″ (5.05 mm). When the base 116 is placed on top of the capillary pedestal 204, the end plate 124 is a perpendicular distance of about 0.03″ (0.65 mm) from a top wall 178 of the capillary pedestal, and the peripheral skirt 126 is perpendicular distance of about 0.02″ (0.38 mm) from the sidewall 206, which defines a capillary well 350 having a volume of approximately 0.012 in3 (200 mm3).
Turning now to FIG. 9, a candleholder 400 for a melting plate candle assembly according to another aspect of the invention is shown including a holder or base 402 and a generally concave melting plate 404 carried within a recessed portion 406 of the base. A solid fuel element and wick holder similar to those already described herein that rest on the melting plate are not shown for purposes of clarity. The melting plate 404 has high thermal conductivity and is similar to other melting plates described previously herein, including a capillary pedestal 408 protruding upwardly therefrom at a centrally disposed wick location. The base 402 includes a wall 410 extending around and angularly disposed outwardly at a zenith angle θ from the melting plate 404 and having an uppermost or top edge 412 disposed above the melting plate. In one aspect, the base 402 and the melting plate 404 have a geometry that is adapted to increase or promote substantially laminar air flow (when surrounded by a calm atmospheric environment) over a pool of molten or liquefied fuel when a flame is disposed in close proximity above the pool during a burn, such as, for example, when a flame is present on a wick such as the wick 108. Such laminar air flow controls the overall temperature of the pool by reducing eddy currents over the pool and/or reducing or minimizing localized hot spots in the pool, which slows volatilization of active volatile ingredients in the fuel, such as a fragrance or insecticide, and thereby extends an effective fragrancing period of the fuel until the fuel is completely burned. When all the fuel is liquefied in the pool during the burn of the melting plate candle, air may be drawn in substantially laminar flow over the top edge 412 of the wall 410 into the recessed portion 406, over the melting plate 404 and a pool of liquefied fuel, such as melted wax, by a heat chimney, or upward air currents, caused by a flame on a wick (not shown) disposed over the capillary pedestal 408. The air currents ascending up the heat chimney also distribute the volatilized active ingredient into the surrounding environment.
In one embodiment, the base 402 and the melting plate 404 have a geometry to increase or promote substantially laminar air flow described by the following equations:
20,000 mm2+(Pmin2−Pmax2)≧SA≧2,500 mm2+(Pmax2−Pmin2); 1.
Dpmax≦(SA/1,000 mm)+{[(Hmin−Pmin)/2]sin θ}; 2.
Pmin≧6(Dp)(cos θ); and/or 3.
Hmin≅Pmin+2[R+(Dp−R)tan θ]; 4
in which:
Pmax is a maximum width across the melting plate 404 in mm;
Pmin is a minimum width across the melting plate 404 in mm;
SA is a projected surface area, or surface area of a two-dimensional projection of an outline, of the melting plate 404 in square millimeters;
Hmin is a minimum width of the base 402 at the top edge 412 in mm;
Dp is a depth of the melting plate 404 from the top edge 412 of the base 402 in mm;
Dpmax is a maximum value for Dp in mm;
R is an outside radius of the upper edge of the base 402 in mm; and
θ is the zenith angle of the wall 410 in degrees.
Equation 1 quantifies an approximate relationship of the projected surface area of the melting plate and the width across the melting plate, within upper and lower constant boundaries, to promote the laminar air flow. Equation 2 quantifies an approximate relationship of the projected surface area of the melting plate 404 and the depth of the melting plate 404 from the top edge 412 of the base 402 to promote the laminar air flow. Equation 3 quantifies an approximate relationship of the minimum melting plate across the melting plate and the depth of the melting plate 404 from the top edge 412 of the base 402 and the zenith angle of the base wall 410 to promote the laminar air flow. Equation 4 quantifies an approximate minimum width of the base 402 at the top edge 412 as a function of the geometries of the melting plate 404 and the base to promote the laminar airflow. Although the equations 1-4 above have been described in relation to a generally rectangular base and holder, the relationships may also be used with other candleholder shapes, such as oval and circular, in order to approach an optimized candleholder geometry. For example, in one embodiment comprising a circular base and melting plate, such as the base 102 and melting plate 104 shown in FIG. 7, Hmin is approximately 3.94″ (100 mm), Pmax and Pmin are both equal to approximately 3.15″ (80 mm), Dp is approximately 0.4″ (10 mm), R is approximately 0.08″ (2 mm), and θ is approximately 45°.
FIGS. 10 and 11 show a candleholder 500, which is generally similar to the candleholder 400 except that the candleholder 500 includes an alignment mechanism for ensuring proper alignment of a melting plate 504 with a base portion 502. The candleholder 500 includes the base portion 502 and the melting plate 504 for supporting a votive candle such as the combination of the fuel element 110, wick holder 106, and wick 108. The base portion 502 is made of a non-flammable material with low heat transmissivity, such as glass or ceramic, and the melting plate is made of a non-flammable material with high heat transmissivity, such as aluminum or other metal, although other materials may also be used. The base portion includes a recess 506 in a top end thereof defined by four upstanding sidewalls 508 and a medial wall 510 spanning the sidewalls spaced below an upper rim 512 of the sidewalls. A bottom end of the base 502 is hollow under the medial wall 510. It is to be understood that the specific shape and configuration of the sidewalls 508 and the bottom end of the base 512 may take almost any shape and form and are not limited to the specific shapes described herein. The melting plate 504 is dish- or bowl-shaped that concaves upwardly with a bottom surface shaped generally complementary to the recess 506 so as to be received in the recess in an operative position. The melting plate 504 has a generally square footprint with a relatively flat bottom wall 514 surrounded by a raised or upwardly curved peripheral portion 516 adjacent an outer peripheral edge 518 and a capillary lobe 520 protruding upwardly from a central portion of the bottom wall 518 for receiving the votive candle (not shown) disposed centrally thereon in a similar manner as described previously herein. An alignment mechanism for ensuring proper alignment of the melting plate 504 within the recess 506 of the base 502 includes a shoulder, such as horizontal step 522, that projects inwardly from an interior side 524 of the sidewalls and extends entirely around the recess 506, and a complementary ledge, such as horizontal ledge 526, that rests on the shoulder. The ledge 526 extends around the melting plate and is vertically disposed between the peripheral edge 518 and the bottom wall 514 of the melting plate 504 and rests on the horizontal step 522 with the peripheral edge pressed against the inner surface 524 of the sidewalls 508 around the entire recess 506. The entire melting plate, including the capillary lobe 520 and the peripheral edge 518, is disposed below the upper rim 512. The melting plate 504 is spaced above the medial wall 510 in the recess 506 with the raised peripheral edge portions 516 pressed against the inner surface 524 of the sidewalls 508 and the capillary lobe 520 projecting upwardly. The melting plate 504 is secured to the base 502 with a bead of adhesive, such as the adhesive 166 (not shown), disposed between the ledge 526 and the shoulder 522. The adhesive may also provide a seal between the peripheral edge 518 of the melting plate 504 and the interior surface 524 of the sidewalls 508 to prevent melted wax or other liquids from seeping under the melting plate. Other substantially complementary alignment configurations may also or alternatively be used for alignment mechanisms within the scope of the present invention. For example, the base shoulder may only include one or more discrete spaced apart step portions, and the melting plate ledge may be continuous or match the discrete ledge portions to provide only one possible correct mating fit between the melting plate and the base. In one embodiment, the alignment feature helps ensure that the melting plate 504 is located in a predetermined relation to the base 502 so that the bottom wall 514 of the melting plate is substantially level and spaced above the medial wall 510 to ensure that melted wax pools around the capillary lobe when the candleholder 450 is placed on a level support surface and minimize heat loss from the melted wax into the base. Of course, the alignment feature may be readily modified to cause a melting plate to rest within the recess in other alignment configurations, such as with the bottom wall 514 contacting the medial wall 510 and/or with the bottom wall 514 disposed at a non-level angle. In yet another embodiment (not shown), the alignment feature may include one or more raised protrusions disposed anywhere within the recess 506 that engage complementary ledges or cavities in the melting plate 504 so as to provide a predetermined alignment between the base 502 and the melting plate. Further, the protrusions may be integral with the base 502, or the protrusions may be formed by a separate object, such as a wire or button (not shown), placed in the cavity. Another alignment mechanism (not shown) within the scope of the present invention may include only one of the ledge and the shoulder without an opposing complementary shoulder or ledge, respectively, wherein the ledge or shoulder urges the melting plate into a predetermined alignment or orientation to the base.
A retainer feature for a magnet 528, such as a circular ring 530 projecting upwardly from a central area of the medial wall 510, is disposed below a cavity 532 in the bottom surface of the melting plate 504 underneath the capillary lobe 520. The ring 530 extends upwardly into the cavity 532 without engaging the bottom surface of the melting plate. The ring 530 acts as a retainer for the magnet 528, which is glued to the melting plate 504 inside the cavity 532, in case the magnet should become unglued from the melting plate. In one embodiment, the ring 530 does not engage, or is spaced from, the bottom surface of the melting plate in order to minimize loss of heat from the melted wax to the base. The retainer is not limited to the specific circular ring form shown in the drawings, but may take other shapes that would help retain the magnet 528 in a predetermined position underneath the capillary lobe 520. For example, the retainer may be a plurality of spaced projections that partially surround the magnet 528, and the magnet may be shaped so as to interfit with the spaced projections in a predetermined orientation. In another example, the retainer may engage the bottom surface of the cavity 532 to help align the melting plate 504 within the recess 506 in addition to the shoulder 522 and ledge 526. In addition, the alignment feature and retainer feature may be readily adapted to work with any other combination of base and melting plate disclosed herein, such as the base 102 and circular melting plate 104, and are not limited to the particular base and melting plate of this embodiment.
The invention having been described in an illustrative manner, it is understood that the terminology used is intended to be in the nature of description rather than of limitation. The various components of the various melting plate candle assemblies described herein may be packaged as an assembled unit, as an unassembled kit including all or a portion of the components, as individual components, and in any combination thereof. Different and various combinations of the above-mentioned components of the various melting plate candle assemblies can also be used in the apparatuses, methods, kits, and combinations herein described. Other variations, modifications, and equivalents of the present invention possible in light of the above teachings are specifically included within the scope of the impending claims.
INDUSTRIAL APPLICABILITY
The candleholder of the present invention may be used to support a votive-type candle, such as the fuel element described herein, to provide rapid melting of the candle wax fuel charge and rapid dispersion of any volatile active contained in the fuel charge. Further, the alignment feature is useful for providing positive placement of a non-circular melting plate in a pre-determined location within a complementary recess, such as the generally square melting plate and recess shown in FIGS. 10 and 11. In addition, the retainer feature in one embodiment may help maintain a magnet in a predetermined location under the capillary lobe.
Numerous modifications to the present invention will be apparent to those skilled in the art in view of the foregoing description. Accordingly, this description is illustrative only and is presented for the purpose of enabling those skilled in the art to make and use the invention and to teach the best mode of carrying out the same. The exclusive rights to all modifications within the scope of the impending claims are reserved.
Patent Application
20060093980
