Flame-resistant wick holder for candle

Information

  • Patent Grant
  • 6793484
  • Patent Number
    6,793,484
  • Date Filed
    Thursday, April 25, 2002
    22 years ago
  • Date Issued
    Tuesday, September 21, 2004
    20 years ago
Abstract
A flame-retardant wick holder for a candle is made of a material having a UL-94 vertical burn test rating of at least V-0, including polymers and ceramics. The wick holder supports a wick at the bottom of a candle. The wick holder material causes the flame on the wick to extinguish when it reaches the holder, thereby preventing flashover of the residual candle fuel at the end of the candle useful life. One version of the holder includes a barrier extending upwardly around the holder for catching a drooping wick from causing secondary wicking and possible flashover near the end of the candle useful life.
Description




FIELD AND BACKGROUND OF THE INVENTION




The present invention relates generally to the field of candle making and in particular to a new and useful holder for a wick which extinguishes the candle flame and inhibits combustion of residual candle fuel in a container for the candle at the end of the candle useful life.




Candle wicks function by capillary action drawing a fuel from a pool up through the wick to the flame. The fuel used in known candles may be paraffin wax, vegetable-based wax or synthetic polymers, like ester-terminated polyamides (ETPA), such as one sold under the name UNICLEAR, or PENRECO gel sold by Pennzoil. Paraffin waxes typically form a melt pool at between 150-200° F., while UNICLEAR polyamide forms a melt pool at between about 200-250° F. The capillary action can be through a fabric or thread wick or through a capillary tube. When the candle fuel pool becomes very shallow, it can become hot enough to vaporize and it no longer needs a wick to burn. This phenomenon is called “flash” or “flashover” and is a problem especially with candles formed or supported in containers.




Once the upper surface of the wax descends nearly to the floor of the container, the shallow pool of wax can be elevated above its flashpoint temperature, typically between 350-450° F. for conventional paraffin waxes and about 440° F. for UNICLEAR, for example. During flashover, the temperature within the candle can be elevated to at least 1200° F. This excessive heat can cause glass containers to break, and it can cause metal tins to scorch the paint off the tin sides and char surfaces on which they are resting. With freestanding candles the molten wax pool must not extend through the candle floor, because wax can flow out onto the candle supporting surface. If the wax flows out or the container of a contained candle breaks, supporting or surrounding objects can be ignited.




An additional problem is that carbon balls may form during burning and fall into the wax pool at the bottom of the candle, or the user may allow matches or wick trimmings to fall to the bottom. These foreign objects may aggravate the flashover problem by becoming secondary wicks if they are ignited by the candle flame.




In conventional candles formed in containers, a wick support like the sustainer


2


shown in

FIG. 1

, is often used to provide lateral support to a wick in a candle to hold the wick in place during pouring of the wax or other fuel. The sustainer


2


also keeps the wick standing upright when the supporting wax around the wick burns very low. The wick is held in a bore formed completely through the sustainer.




Sustainers of this type are popular for use in candles because they are easily assembled using machines. The wick is simply inserted through the bore and held in place by crimping the bore. The cylindrical plate of the sustainer


2


is easily affixed to a container for holding a candle.




During burning, molten wax


4


is drawn upwardly through the wick sides initially, and is carried to the flame. As the upper surface of the molten wax


4


descends to near the top end of the sustainer


2


, the heat from the flame liquifies the wax all around the sustainer


2


. Once this wax is liquified, molten wax


4


can be drawn from beneath the sustainer


2


through the bore and upwardly to the flame. This permits the majority of the wax


4


to be consumed before the flame goes out from lack of fuel. When the depth of the molten wax


4


is sufficiently small, the flashover problem can occur.




Flashover is a problem which causes significant damage and harm. Flashover can result in house fires and burns to people who use candles decoratively. This is a problem which is being given more attention by consumer groups and needs to be solved in an economical way. The need exists for an inexpensive and simple safety device for preventing or significantly decreasing the likelihood of flashover.




Several different approaches to solving the problem of flashover have been provided. U.S. Pat. No. 5,842,850, for example, discloses several embodiments of a wick sustainer of the type shown in

FIG. 1

having the bottom end of the sustainer sealed against permeation by a candle fuel. The sealed bottom prevents molten candle fuel from being drawn through the wick in the bore of the wick sustainer, causing the candle to extinguish when the fuel level drops below the level of the exposed wick above the wick sustainer, provided the bore is not punctured during assembly.




U.S. Pat. No. 4,332,548 teaches a transparent safety disc at the bottom of a candle. The safety disc is formed by a thermoplastic polyamide resin, combined with a flammable solvent for the resin that is compatible with the candle material. The candle is also transparent. A wick holder and wick are placed on a layer of the resin mixture followed by pouring the candle material around the wick and wick holder and over the resin layer. The safety disc layer helps prevent flameups due to its higher melting point and other characteristics which render it substantially non-flammable in the presence of a candle flame.




U.S. Pat. No. 3,797,990 discloses a safety layer for a candle formed from a higher melting point wax. The higher melting point wax in the safety layer is not combustible by a candle flame. The safety layer may be positioned around or below the wick clip and wick bottom. When the candle flame nears the safety layer and causes it to melt, the wax in the safety layer begins to block the wick, subsequently resulting in the candle flame being extinguished due to lack of fuel.




U.S. Pat. No. 2,831,330 teaches adding polybutene polymers to a candle wax in different proportions to first extend the burn time of the candle and then in an amount sufficient to extinguish the candle due to lack of fuel. Polybutene polymer provided in concentrations of about 15% in a portion of a candle is disclosed as being capable of extinguishing a candle when the candle flame reaches the area of higher polybutene concentration.




U.S. Pat. No. 5,127,922 describes a candle having an outer shell which includes 10-30% of a fire retardant material. The fire retardant material is mixed with a thermoplastic compound, so that the shell will slowly melt and mix with the candle fuel as the candle burns. The fire retardant can be a silicone elastomer, a non-halogenated, inorganic flame retardant or an alumina trihydrate, among other compounds.




Other mechanical devices for extinguishing a candle prior to the point where a flashover or flame-up would occur are known, such as taught by U.S. Pat. No. 4,818,214 for a candle having a heat-shrinkable sleeve around the candle near the base. When the candle burns down sufficiently that the candle flame is near the sleeve, the heat activates the sleeve, causing it to shrink inwardly, constricting the wick and extinguishing the flame.




Several of the prior art devices and compounds use flame retardants or flame-resistant materials to extinguish the flame. But, the prior compounds and apparatus for preventing flashover or extinguishing a candle flame can be complex and require particular mixtures of components. Further, some prior art flame-retardant coatings and mixtures for use on wicks or in candle fuels can also make the candle difficult to use by extinguishing the candle prematurely and requiring relighting well before the end of the useable life.




Polyethylene discs with central bores for holding wicks have been suggested for use as the wick holder in a candle to prevent flashover. However, testing has revealed that polyethylene discs soften at 200° F. and can combust rather easily when exposed to a burning candle flame. Thus, polyethylene, while easy to mold, is not suitable for providing a non-combustible wick holder for extinguishing a candle flame at the end of the candle useful life.




Clearly, few simple solutions for preventing flashover which are easy to manufacture and incorporate into a candle are available.




A flame-resistant and retardant wick holder which can be easily incorporated into candles in place of existing wick sustainers is needed. Plastics are a material which can be easily molded and formed, but which can also combust and produce very toxic by-products.




A widely accepted test to determine flammability of plastics used in products is found in Underwriter Laboratories UL-94 standard. ASTM standard 3801-96 and ISO standard 1210-1991 are similar standards having similar tests and equivalent ratings.




The UL-94 standard includes horizontal and vertical burn tests which can be used to rate the flammability of plastics. The vertical burn test is considered more stringent and a plastic can receive one of several ratings, depending on its flammability.




A rating of V-0 from the UL-94 vertical burn test indicates that combustion of the product stops within ten seconds after two applications of ten seconds each of a flame to a test bar of the plastic material, and the material must not produce any flaming drips. The V-0 rating is considered the best rating of non-flammability for a plastic.




The UL-94 vertical burn test is performed by suspending a ½ inch wide by 5 inch long test rod of the plastic material over a cotton pad. A burner flame is applied to the lower end of the test rod for ten seconds, following which combustion of the rod, if any is observed until it stops. The burner flame is applied to the test rod for a second period of ten seconds. Observations of the test rod following application of the flame determine the rating the material will receive. In addition to the requirements noted above, the specimen must not begin glowing or flaming combustion after application of the burner flame. The rating for the material is based on the thickness of the test rod used. That is, a ¼ inch thick test rod which achieves a V-0 rating qualifies the material of the test rod used in products in ¼ or greater thicknesses. The thinner the test rod, the less combustible the material.




Polyethersulfone (PES) is one such material which has a V-0 rating for the UL-94 vertical burn test at a thickness of 0.8 mm, or about {fraction (1/32)} inches. Polyethersulfone is a thermoplastic material which is commonly used for electrical applications such as wire insulation, connectors, molded interconnects and housings for starters. Polyethersulfone is also known for use in other applications as well where heat resistance is desired. However, while the combustion characteristics of polyethersulfone are known, PES is not known for use in applications involving open flames.




SUMMARY OF THE INVENTION




It is an object of the present invention to provide a non-combustible wick holder for a candle to eliminate flameover.




It is a further object of the invention to provide a wick holder which will extinguish a candle flame on a wick when the flame reaches the wick holder.




Yet another object of the invention is to provide a non-flammable wick holder that is easily incorporated into a candle supported in a container for preventing flashover of the candle when the wick burns down to the wick holder.




Accordingly, a flame-retardant wick holder for a candlewick is provided which effectively extinguishes the candle flame on the wick when the flame and fuel level reach the wick holder. The flame-retardant wick holder is a disc made of a polyethersulfone with a bore through the center for holding a candle wick. The top surface of the disc may be sloped away from the bore in the center, so that the top surface has a conical shape, or it may be flat. A vertical barrier or ridge may be provided extending upwardly from all around the outer edge of the disc to prevent or reduce secondary wicking. The barrier has grooves or through-holes for permitting molten wax to drain off the sloped top surface of the disc.




The wick holder is sufficiently thick, or shaped to have a maximum height, so that the upper end of the bore is raised above the floor of the container where the disc is used to prevent candle fuel from melting and rising through the wick in the bore. The wick holder may have a diameter or width the same as the container it is used in, or it may be as small as about one inch across. The wick holder may be shaped to accommodate the shape of the container, or it is circular.




The polyethersulfone (PES) used to make the wick holder is selected from those having a UL-94 vertical burn test rating of at least V-0 or which is non-combustible and intumescent when heated. Other polymers which are also non-combustible and intumescent like polyethersulfone can be used to make the wick holder with similar effect.




The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated.











BRIEF DESCRIPTION OF THE DRAWINGS




In the drawings:





FIG. 1

is a side sectional view of a prior art candle and wick holder;





FIG. 2

is a partial sectional side elevation view of a candle having a wick holder according to the invention;





FIG. 3

is a top plan view of the wick holder of

FIG. 2

;





FIG. 4

is a partial sectional side elevation view of an alternative embodiment of the candle and wick holder of

FIG. 2

;





FIG. 5

is a sectional top plan view of the wick holder of

FIG. 4

;





FIG. 6

is a top plan view of yet another embodiment of a candle and wick holder of the invention;





FIG. 7

is a side elevation view of the wick holder of

FIG. 6

;





FIG. 8

is a partial sectional side elevation view of a pillar candle with a further embodiment of a wick holder according to the invention;





FIG. 9

is a sectional side elevation view of yet another embodiment of a wick holder of the invention;





FIG. 10

is a side elevation view of a fifth embodiment of a wick holder according to the invention;





FIG. 11

is a sectional side elevation view of the wick holder of

FIG. 10

;





FIG. 12

is a top plan view of the wick holder of

FIG. 10

;





FIG. 13

is a side elevation view of an the wick holder of

FIG. 10

with an alternative barrier drain; and





FIG. 14

is a sectional side elevation view of the wick holder of FIG.


13


.











DESCRIPTION OF THE PREFERRED EMBODIMENTS




Referring now to the drawings, in which like reference numerals are used to refer to the same or similar elements,

FIG. 2

shows a sectional view of a filled candle


50


formed by a container


20


holding candle fuel


100


around wick


30


. Wick


30


extends through the candle fuel


100


from the fuel top surface


105


to the container floor


22


. The lower end of the wick is inserted through bore


18


of a disc-shaped wick holder


10


.




As seen in

FIGS. 2 and 3

, the wick holder


10


has a cylindrical base


14


, a sloped upper surface


12


and a horizontal top surface


16


. The bore


18


extends vertically through the wick holder


10


between the horizontal top surface


16


and the holder bottom


19


. The wick


30


can be held within the bore


18


, for example, by frictional fit between the wick


30


and bore


18


or by an adhesive, among other things.




The wick holder


10


preferably rests with the holder bottom


19


supported on container floor


22


. In such cases, the candle


50


may be formed by inserting wick


30


through bore


18


and placing wick holder


10


on the floor


22


of the container


20


. The wick holder


10


can be secured in place on the container floor


22


, such as with a small amount of adhesive or a tacky candle fuel material. Then, liquid candle fuel


100


is poured into the container


20


around the wick holder


10


and wick


30


until the top surface


105


of the candle is at a desired level, and the wick


30


still protrudes from the top surface


105


. The candle fuel


100


is allowed to solidify around the wick


30


in the container


20


before it is used by lighting the wick


30


.




The wick holder is preferably made of a polyethersulfone, such as RADEL polyethersulfone sold by BP AMOCO. The polyethersulfone selected must have a UL-94 flammability test rating of at least V-0 or better. It has been found that polyethersulfone used for the wick holder


10


material causes a flame on a candle wick


30


to extinguish when the wick


30


and candle fuel


100


reach the horizontal top surface


16


of the wick holder


10


. The polyethersulfone does not support sustained combustion, so the candle flame cannot be sustained when the wick


30


is deprived of candle fuel


100


by the presence of the wick holder


10


.




The sloped upper surface


12


, when present, may be formed at any angle between 0° and 90°. When the upper surface


12


is at 0° or 90° it is either merged into the horizontal top surface


16


or the vertical side of base


14


, respectively. Similarly, the horizontal top surface


16


around bore


18


may be eliminated (see FIG.


8


), so that the sloped upper surface


12


provides a conical shape to the top of the wick holder


10


. The sloped surface


12


helps drain molten candle fuel


100


away from the wick


30


so that it cannot fuel the candle flame. Preferably, the sloped surface


12


is present and ranges between a 5° and 30° angle with a horizontal plane.




The polyethersulfone wick holder


10


acts as a heat sink as well, to disperse heat from the burning candle flame away from the area immediately around the candle flame to reduce the size of the molten fuel puddle produced when the flame is at or near the level of the wick holder.





FIGS. 4-9

illustrate alternate shapes for the wick holder


10


.




The wick holder


10


in

FIGS. 4 and 5

has a square shape with only a planar top surface


16


. The wick holder


10


extends across substantially the entire width between the walls of the container


20


. In this embodiment, the container


20


has a square shape and the wick holder


10


is square as well to conform to the container


20


shape. The wick holder


10


has several legs


15


on which bottom surface


19


can be supported above the floor


22


of the container. Bore


18


is preferably provided in about the center of the wick holder


10


.





FIGS. 6 and 7

illustrate an embodiment of the wick holder


10


for use with multiple-wick candles. The wick holder has three bores


18


for each holding a separate wick. The bores


18


are spaced around the horizontal upper surface


16


to define a triangle. The wick holder


10


has a sloped upper surface


12


around the horizontal top surface


16


.





FIG. 8

shows a pillar candle


70


made from candle fuel


100


and having a wick


30


extending above candle top surface


105


. The wick


30


extends downwardly through the candle fuel


100


where it is secured in a wick clip


60


inserted through the bore


18


of wick holder


10


. The wick clip


60


may be of the type used in prior art candles to hold the wick in place. The wick


30


is crimped into tube


62


, which defines clip bore


68


surrounding wick


30


. The base of the wick clip


60


may be exposed outside the candle fuel


100


or slightly encased within the fuel


100


against the holder bottom


19


.





FIG. 9

illustrates an embodiment of the wick holder


10


which is formed as a hollow cone or cap. The outer sides of the wick holder


10


are formed by sloped surface


12


, which taper from the bottom edge surface


19


to the bore


18


at the top. Since the holder


10


is hollow, a corresponding inner sloped side


120


is formed opposite the sloped surface


12


. A wick


30


is inserted through bore


18


and held by a frictional fit or adhesive. When the wick holder


10


is a hollow cone as shown in

FIG. 9

, it is very easy to make by injection molding using polyethersulfone.




The cone-shaped holder of

FIG. 9

is preferably at least about ½ inch in diameter at bottom edge surface


19


and most preferably at least about 1 inch in diameter or greater. The height H of the wick holder


10


should be at least about ⅛ inch, and is preferably between about ¼ inch and 1 inch. The thickness of the holder


10


between sloped surface


12


and inner sloped side


120


should be at least about {fraction (1/32)} inch or greater.





FIGS. 10-14

illustrate a further embodiment of the wick holder


10


in which a vertically extending barrier


80


is provided all around the circumference of the holder


10


. The barrier


80


is provided with either grooves


85


(

FIGS. 10-12

) or through holes


88


(

FIGS. 13

,


14


) for draining molten wax or other fuel off the wick holder sloped surface


12


. The wick holder


10


may have cavities


90


in the base to reduce the amount of material required to make the holder


20


. The thicknesses of the walls defining the cavity


90


should not be less than about {fraction (1/32)} inch.




The wick holder


10


should have the same dimensions as discussed above, except that the holder


10


includes the circumferential barrier


80


extending above cylindrical base portion


14


. The barrier preferably extends above the base portion


14


by between ⅛ inch to ½ inch. The remaining dimensions of the wick holder


10


may be the same as in other embodiments.




The barrier


80


prevents a wick


30


from falling over into fuel surrounding the holder


10


and creating a secondary wicking effect. The barrier is preferably located at the perimeter edge of the wick holder


10


, although it may be positioned closer to the bore


18


when the wick holder


10


diameter is large. It should be understood that the wick holder


10


can be shaped as in any of the prior embodiments and the barrier


80


will be positioned at the same perimeter edge as shown with the circular wick holder


10


of

FIGS. 10-14

.




When a candle has burned down sufficiently that the wick holder


10


is needed to help prevent flashover from occurring, the barrier


80


will support a leaning wick above the surrounding fuel. As shown in

FIGS. 10

,


11


,


13


, and


14


, the barrier


80


is preferably higher than the upper end of the sloped surface


12


of the holder


10


where bore


18


is located. Alternatively, the barrier


80


will retain the burning end of the wick on the top sloped surface


12


of the holder


10


until it is safely extinguished.




The grooves


85


and drain holes


88


are provided so that as the candle burns down toward the sloped surface


12


of the wick holder


10


, the fuel covering the holder


10


can drain off the sloped surface


12


. When grooves


85


are used, each groove


85


should have a width less than the width of the wick (and bore


18


). The narrower grooves


85


will prevent the wick from being able to fall into one of the grooves


85


and onto fuel surrounding the wick holder


10


. The drain holes


88


may be any size, but are preferably narrower or shorter than the diameter of a wick used with the holder


10


to prevent the wick from passing through one of the drain holes


88


. The grooves


85


or drain holes


88


should not be smaller than {fraction (1/32)} inch wide, so that fuel will drain effectively off the sloped surface


12


.




The sloped surface


12


can be arranged at any angle from 0-90°, relative to horizontal. When the wick holder


10


includes barrier


80


, the sloped surface


12


is preferably angled at between 1-10°, and most preferably about 4° relative to horizontal.




The drain holes


88


or grooves


85


are spaced around the circumference of the barrier


80


. Preferably, they are spaced equidistant from each other. They may be used in combination as well, so that a groove


85


is provided at one point of the barrier


80


, while a drain hole


88


is provided 180° opposite.




At least one groove


85


or drain hole


88


is needed to ensure that fuel will have a path for flowing off the sloped surface


12


. Preferably, there are three grooves


85


or drain holes


88


, and most preferably, the three openings are arranged spaced 120° apart around the barrier


80


.




Polyethersulfone (PES) is a preferred material for making the wick holder


10


for several reasons. PES is a thermoplastic capable of withstanding elevated temperatures. This characteristic allows PES to be easily molded using injection molding techniques. PES is resistant to acids, bases, aliphatic hydrocarbons, oils and fat, among other things, so that it is unlikely to absorb fragrance oils or candle fuels which might make the wick holder


10


somewhat combustible.




Polyethersulfone melts at about 230° C. (about 446° F.). It has a Vicat softening point of about 215° C. (419° F.). A very favorable feature of polyethersulfone is that it is intumescent. That is, when PES is heated, such as by a candle flame, it begins to swell, which in the region of the bore


18


, acts to cut off the capillary action in the wick.




Further, PES can appear transparent to yellowish, so that it is usable in transparent candles.




PES is substantially non-combustible, having a UL-94 standard vertical burn test rating of V-0 for thicknesses as small as {fraction (1/32)} inch. The resistance to combustion of PES combined with heat dissipation properties of a sufficiently large wick holder


10


results in a wick holder according to the invention being capable of extinguishing a candle flame when the flame reaches the level of the wick holder upper surface.




Several tests were conducted with different size wick holders made from PES in accordance with the invention to verify the ability of the wick holders to extinguish a candle flame. The test samples and results were as follows.




Test 1




Three cylindrical paraffin wax candles and three cylindrical candles made from UNICLEAR each having a PES wick holder ⅜ inches in total height, with a 10° slope to the sloped upper surface


12


, {fraction (3/32)} inch diameter bore


18


and one inch diameter across were provided. The candles were burned 12 hours per day until the candle was at the end of its useful life. The candles were each monitored to determine if they extinguished on their own at the end of the candle useful life. In particular, the candles were monitored to determine if they self-extinguished once the top surface of the PES wick holder


10


was exposed, or alternatively, if secondary wicking occurred, such as from carbon ball buildup or wick pieces in the residual candle fuel. It was observed that all six candles extinguished upon reaching the PES wick holder, despite the presence of carbon balls adjacent the wick. The width of the PES wick holder prevented wick pieces from causing any secondary wicking.




Test 2




Three cylindrical paraffin wax candles and three cylindrical candles made from UNICLEAR each having a PES wick holder ⅜ inches in total height, with a 10° slope to the sloped upper surface


12


, {fraction (5/32)} inch diameter bore


18


and one inch diameter across were provided. The candles were burned and observed as in Test 1, above. Again, all six candles self-extinguished despite the presence of carbon balls and some small wick pieces which were trapped on the sloped upper surface of the wick holder and prevented from igniting any candle fuel. The PES holder did not experience any combustion.




Test 3




Three cylindrical paraffin wax candles and three cylindrical candles made from UNICLEAR each having a PES wick holder ⅜ inches in total height, with a 20° slope to the sloped upper surface


12


, {fraction (3/32)} inch diameter bore


18


and one inch diameter across were provided. The candles were burned and observed as in Test 1, above. All six candles self-extinguished.




Test 4




Three cylindrical paraffin wax candles and three cylindrical candles made from UNICLEAR each having a PES wick holder ⅜ inches in total height, with a 20° slope to the sloped upper surface


12


, {fraction (5/32)} inch diameter bore


18


and one inch diameter across were provided. The candles were burned and observed as in Test 1, above. All six candles self-extinguished.




Test 5




Three cylindrical paraffin wax candles and nine cylindrical candles made from UNICLEAR each having a PES wick holder ¼ inches in total height, with a 10° slope to the sloped upper surface


12


, {fraction (5/32)} inch diameter bore


18


and one inch diameter across were provided. The candles were burned and observed as in Test 1, above. All but one of the candles self-extinguished despite the presence of carbon balls and wick pieces.




Test 6




Three cylindrical paraffin wax candles and three cylindrical candles made from UNICLEAR each having a PES wick holder ¼ inches in total height, with a 20° slope to the sloped upper surface


12


, {fraction (3/32)} inch diameter bore


18


and one inch diameter across were provided. The candles were burned and observed as in Test 1, above. All six candles self-extinguished.




Test 7




Three cylindrical paraffin wax candles and two cylindrical candles made from UNICLEAR each having a PES wick holder ¼ inches in total height, with a 20° slope to the sloped upper surface


12


, {fraction (5/32)} inch diameter bore


18


and one inch diameter across were provided. The candles were burned and observed as in Test 1, above. All five candles self-extinguished.




In each of the tests above, a 44-32-18c wick from Atkins and Pierce was used.




As shown by the tests, a relatively small wick holder


10


incorporated into a candle can provide a self-extinguishing feature. Preferably, the wick holders


10


will be at least 1 inch in diameter, up to the diameter of the container or candle the wick holder is used with. The wick holders can be between {fraction (1/32)} inch thick to 1 inch or more, but are preferably about {fraction (3/32)} to ½ inch thick between the bottom surface


19


and horizontal top surface


16


or top opening of the bore


18


when there is no top surface


16


. The wick holders


10


should position the top opening of the bore


18


at about ⅛ inch above the bottom of the candle or container bottom


22


, and preferably between about ¼ inch and 1 inch above the container bottom


22


or candle bottom.




Other polymers having similar properties to PES can be used for the wick holder


10


. In particular, the polymer must not support combustion by a candle flame. Polymers which have at least a V-0 rating for sample thicknesses of {fraction (1/32)} to ⅛ inch from the UL-94 test are good candidates. Other materials having a UL-94 test rating of V-0 for the same thicknesses may be used as well, including ceramics. Preferably the V-0 rating can be obtained for material thicknesses as low as {fraction (1/32)} inch, but materials rated V-0 at thicknesses up to ¼ inch are acceptable.




Preferably, the material selected for the wick holder


10


will also be intumescent when heated, so that the same constriction effect in the bore


18


is provided when the candle flame reaches the top surface


16


of the wick holder


10


.




Acceptable polymers include polyphenylsulfones (PPS) and polyvinylchloride (PVC) which meet the non-combustion and intumescent requirements, will not melt at temperatures less than about 350° F. and can also be easily injection molded. Specific polymers include RADEL A-300, polysulfone P-1720 and polysulfone P-1700, available from AMOCO.




As a further alternative, ceramics which are heat resistant and do not support combustion could be used for the wick holder


10


. Although ceramics will not usually have the same intumescent properties as the preferred polymers, the heat resistant and non-combustible nature of ceramics at the temperatures involved with burning candles make them suitable for use.




While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.



Claims
  • 1. A wick holder for a candle having a wick, the candle made from a fuel capable of melting to form a liquid pool and traveling by capillary action to a flame burning on the wick, the wick holder comprising:an intumescent body having a top surface, a bottom surface, a side wall connecting the top surface to the bottom surface, and a cylindrical bore sized to hold the wick passing through the body between the top and bottom surfaces; a barrier extending vertically above the top surface; and at least one groove or drain hole in the barrier, wherein the barrier and body are both made from a non-combustible material.
  • 2. A wick holder according to claim 1, wherein the non-combustible material is selected from the group consisting of polyethersulfones, polyphenylsulfones, polyvinylchloride, polysulfones and ceramics which have a UL-94 vertical burn test rating of V-0 for thicknesses of {fraction (1/32)} inch.
  • 3. A wick holder according to claim 2, wherein the body is a cylindrical disk.
  • 4. A wick holder according to claim 3, wherein the top surface is sloped downwardly from around the bore toward the side wall.
  • 5. A wick holder according to claim 1, wherein the body is a cylindrical disk.
  • 6. A wick holder according to claim 5, wherein the top surface is sloped downwardly from around the bore toward the side wall.
  • 7. A wick holder according to claim 6, wherein the barrier is positioned at the perimeter of the cylindrical disk.
  • 8. A wick holder according to claim 1, wherein the barrier is positioned at a perimeter of the body.
  • 9. A wick holder according to claim 1, wherein the barrier is formed integral with the body.
  • 10. A self-extinguishing candle, comprising:a body having a top surface, a bottom surface, a side wall connecting the top surface to the bottom surface, and a cylindrical bore for receiving the wick passing through the body between the top and bottom surfaces; a barrier extending vertically above the top surface; at least one groove or drain hole in the barrier, wherein the barrier and body are both made from a non-combustible material; a candle fuel surrounding the body and barrier; a wick inserted through the bore and extending through the candle fuel so that at least a portion of the wick is exposed above the candle fuel for lighting to melt the candle fuel adjacent the wick, the body extinguishing a flame burning on the wick when the flame reaches the top surface of the body.
  • 11. A self-extinguishing candle according to claim 10, wherein the non-combustible material is selected from the group consisting of polyethersulfones, polyphenylsulfones, polyvinylchloride, polysulfones and ceramics which have a UL-94 vertical burn test rating of V-0 for thicknesses of {fraction (1/32)} inch.
  • 12. A self-extinguishing candle according to claim 11, wherein the body is a cylindrical disk.
  • 13. A self-extinguishing candle according to claim 12, wherein the top surface is sloped downwardly from around the bore toward the side wall.
  • 14. A self-extinguishing candle according to claim 10, further comprising a container holding the candle fuel, the body resting on a floor of the container.
  • 15. A self-extinguishing candle according to claim 10, wherein the body is a cylindrical disk.
  • 16. A self-extinguishing candle according to claim 15, wherein the barrier is positioned at a perimeter of the cylindrical disk.
  • 17. A self-extinguishing candle according to claim 15, wherein the barrier is formed integral with the body.
  • 18. A self-extinguishing candle according to claim 15, wherein the top surface is sloped downwardly from around the bore toward the side wall.
  • 19. A wick holder for a candle having a wick, the candle made from a fuel capable of melting to form a liquid pool and traveling by capillary action to a flame burning on the wick, the wick holder comprising:a cylindrical disk body having a top surface, a bottom surface, a side wall connecting the top surface to the bottom surface, and a cylindrical bore sized to hold the wick passing through the body between the top and bottom surfaces wherein the non-combustible material is selected from the group consisting of polyethersulfones, polyphenylsulfones, polyvinylchloride, polysulfones and ceramics which have a UL-94 vertical burn test rating of V-0 for thicknesses of {fraction (1/32)} inch; and, a barrier extending vertically from above the top surface at a perimeter of the body, at least one groove or drain hole being formed in the barrier, the top surface of the body sloping downwardly from the bore toward the barrier.
  • 20. A wick holder according to claim 19, wherein the barrier is formed integral with the body.
  • 21. A wick holder according to claim 19, wherein the at least one groove or drain hole comprises three grooves or drain holes.
  • 22. A wick holder according to claim 21, wherein the three grooves or drain holes are spaced equidistant apart around the barrier.
  • 23. A wick holder according to claim 19, wherein the bottom surface, cylindrical bore and side walls define a cavity in the body.
CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of application Ser. No. 09/931,826 filed Aug. 17, 2001, now U.S. Pat. No. 6,508,644, the entirety of which is hereby incorporated by reference.

US Referenced Citations (4)
Number Name Date Kind
803848 Pereira Nov 1905 A
1842904 Greenan Jan 1932 A
5927312 Dryden et al. Jul 1999 A
6508644 Pesu et al. Jan 2003 B1
Foreign Referenced Citations (6)
Number Date Country
2415652 Oct 1975 DE
36 30 712 Mar 1988 DE
647 Mar 1896 DK
1423888 Nov 1965 FR
291 Jan 1868 GB
02-21504 Jan 1990 JP
Continuation in Parts (1)
Number Date Country
Parent 09/931826 Aug 2001 US
Child 10/131943 US