U.S. patent application number 10/257201 was filed with the patent office on 2004-02-19 for flame resistant wick holder for candle.
Invention is credited to Destefano, Fabian, Pesu, Bradley D., Romano, Joseph P., Thomas, Cheriyan B..
Application Number | 20040033463 10/257201 |
Document ID | / |
Family ID | 31715384 |
Filed Date | 2004-02-19 |
United States Patent
Application |
20040033463 |
Kind Code |
A1 |
Pesu, Bradley D. ; et
al. |
February 19, 2004 |
Flame resistant wick holder for candle
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.
Inventors: |
Pesu, Bradley D.; (Gahanna,
OH) ; Romano, Joseph P.; (Worthington, OH) ;
Destefano, Fabian; (Powell, OH) ; Thomas, Cheriyan
B.; (New Albany, OH) |
Correspondence
Address: |
NOTARO AND MICHALOS
100 DUTCH HILL ROAD
SUITE 110
ORANGEBURG
NY
10962-2100
US
|
Family ID: |
31715384 |
Appl. No.: |
10/257201 |
Filed: |
October 9, 2002 |
PCT Filed: |
August 16, 2002 |
PCT NO: |
PCT/US02/26313 |
Current U.S.
Class: |
431/289 |
Current CPC
Class: |
F23D 3/26 20130101; F23D
3/16 20130101; F23D 3/08 20130101 |
Class at
Publication: |
431/289 |
International
Class: |
F23D 003/16 |
Claims
What is claimed is:
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: 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; and a barrier extending
vertically above the top surface, wherein the barrier and body are
both made from a non-combustible material.
2. A wick holder according to claim 1, further comprising at least
one groove or drain hole formed in the barrier.
3. A wick holder according to claim 2, 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.
4. A wick holder according to claim 3, wherein the body is a
cylindrical disk.
5. A wick holder according to claim 4, wherein the top surface is
sloped downwardly from around the bore toward the side wall.
6. A wick holder according to claim 2, wherein the body is a
cylindrical disk.
7. A wick holder according to claim 6, wherein the top surface is
sloped downwardly from around the bore toward the side wall.
8. A wick holder according to claim 7, wherein the barrier is
positioned at the perimeter of the cylindrical disk.
9. A wick holder according to claim 8, wherein the barrier is
positioned at a perimeter of the body.
10. A wick holder according to claim 2, wherein the barrier is
formed integral with the body.
11. 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.
12. A wick holder according to claim 11, wherein the body is a
cylindrical disk.
13. A wick holder according to claim 12, wherein the top surface is
sloped downwardly from around the bore toward the side wall.
14. A wick holder according to claim 12, wherein the top surface is
sloped downwardly from adjacent the side wall toward the bore.
15. A wick holder according to claim 1, wherein the body is a
cylindrical disk.
16. A wick holder according to claim 15, wherein the top surface is
sloped downwardly from around the bore toward the side wall.
17. A wick holder according to claim 16, wherein the barrier is
positioned at the perimeter of the cylindrical disk.
18. A wick holder according to claim 1, wherein the barrier is
positioned at a perimeter of the body.
19. A wick holder according to claim 1, wherein the barrier is
formed integral with the body.
20. 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, 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.
21. A self-extinguishing candle according to claim 20, 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.
22. A self-extinguishing candle according to claim 21, wherein the
body is a cylindrical disk.
23. A self-extinguishing candle according to claim 22, wherein the
top surface is sloped downwardly from around the bore toward the
side wall.
24. A self-extinguishing candle according to claim 22, wherein the
top surface is sloped downwardly from the side wall toward the
bore.
25. A self-extinguishing candle according to claim 20, further
comprising a container holding the candle fuel, the body resting on
a floor of the container.
26. A self-extinguishing candle according to claim 20, wherein the
body is a cylindrical disk.
27. A self-extinguishing candle according to claim 26, wherein the
barrier is positioned at a perimeter of the cylindrical disk.
28. A self-extinguishing candle according to claim 26, wherein the
barrier is formed integral with the body.
29. A self-extinguishing candle according to claim 26, wherein the
top surface is sloped downwardly from around the bore toward the
side wall.
30. A self-extinguishing candle according to claim 26, wherein the
top surface is sloped downwardly from the side wall toward the
bore.
31. A self-extinguishing candle according to claim 20, further
comprising at least one groove or drain hole formed in the
barrier.
32. A self-extinguishing candle according to claim 31, 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.
33. A self-extinguishing candle according to claim 32, wherein the
body is a cylindrical disk.
34. A self-extinguishing candle according to claim 33, wherein the
top surface is sloped downwardly from around the bore toward the
side wall.
35. A self-extinguishing candle according to claim 31, further
comprising a container holding the candle fuel, the body resting on
a floor of the container.
36. A self-extinguishing candle according to claim 31, wherein the
body is a cylindrical disk.
37. A self-extinguishing candle according to claim 36, wherein the
barrier is positioned at a perimeter of the cylindrical disk.
38. A self-extinguishing candle according to claim 36, wherein the
barrier is formed integral with the body.
39. A self-extinguishing candle according to claim 36, wherein the
top surface is sloped downwardly from around the bore toward the
side wall.
40. 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 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 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.
41. A wick holder according to claim 40, further comprising a
barrier extending vertically from above the top surface.
42. A wick holder according to claim 41, wherein the barrier is
formed integral with the body.
43. A wick holder according to claim 41, further comprising at
least one groove or drain hole formed in the barrier.
44. A wick holder according to claim 42, wherein the body is a
cylindrical disk.
45. A wick holder according to claim 44, wherein the barrier is
located at a perimeter of the disk.
46. A wick holder according to claim 45, wherein the top surface
slopes downwardly from the bore toward the barrier.
47. A wick holder according to claim 45, wherein the top surface
slopes downwardly from the barrier toward the bore.
48. 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 body having a top surface, a bottom surface, and a
cylindrical bore for receiving the wick passing through the body
between the top and bottom surfaces, the body made from a
non-combustible, intumescent polymer, the body extinguishing the
flame burning on the wick when the flame reaches the top surface of
the body.
49. A wick holder according to claim 48, wherein the polymer is
selected from the group consisting of polyethersulfones,
polyphenylsulfones and polyvinylchloride.
50. A wick holder according to claim 48, wherein the body is a
cylindrical disk with a sloped upper surface extending from around
an opening of the bore in the top surface downwardly toward a side
edge of the disk.
51. A wick holder according to claim 48, wherein the
non-combustible, intumescent polymer is a polyethersulfone.
52. A wick holder according to claim 51, wherein the body is a
cylindrical disk with a sloped upper surface extending from around
an opening of the bore in the top surface downwardly toward a side
edge of the disk.
53. A wick holder according to claim 52, further comprising a
plurality of spaced apart feet extending from the bottom surface of
the disk.
54. A wick holder according to claim 48, wherein the body is a
hollow cone with a sloped upper surface extending from around an
opening of the bore in the top surface downwardly toward a bottom
edge of the cone.
55. A self-extinguishing candle, comprising: a body having a top
surface, a bottom surface, and a cylindrical bore passing through
the body between the top and bottom surfaces, the body made from a
non-combustible, intumescent polymer; a candle fuel surrounding the
body; 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.
56. A self-extinguishing candle according to claim 55, wherein the
polymer is selected from the group consisting of polyethersulfones,
polyphenylsulfones and polyvinylchloride.
57. A self-extinguishing candle according to claim 56, wherein the
body is a cylindrical disk with a sloped upper surface extending
from around an opening of the bore in the top surface downwardly
toward a side edge of the disk.
58. A self-extinguishing candle according to claim 56, further
comprising a plurality of spaced apart feet extending from the
bottom surface of the disk.
59. A self-extinguishing candle according to claim 55, further
comprising a container holding the candle fuel, the body resting on
a floor of the container.
60. A self-extinguishing candle according to claim 59, wherein the
polymer is polyethersulfone.
61. A self-extinguishing candle according to claim 60, wherein the
body is a cylindrical disk with a sloped upper surface extending
from around an opening of the bore in the top surface downwardly
toward a side edge of the disk.
62. A self-extinguishing candle according to claim 55, wherein the
body is a hollow cone with a sloped upper surface extending from
around an opening of the bore in the top surface downwardly toward
a bottom edge of the cone.
Description
FIELD AND BACKGROUND OF THE INVENTION
[0001] 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.
[0002] 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.degree. F.,
while UNICLEAR polyamide forms a melt pool at between about
200-250.degree. 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.
[0003] 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.degree.
F. for conventional paraffin waxes and about 440.degree. F. for
UNICLEAR, for example. During flashover, the temperature within the
candle can be elevated to at least 1200.degree. 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.
[0004] 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.
[0005] 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.
[0006] 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.
[0007] 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.
[0008] 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.
[0009] 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.
[0010] 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.
[0011] 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.
[0012] 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.
[0013] 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.
[0014] 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.
[0015] 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.
[0016] 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.degree. 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.
[0017] Clearly, few simple solutions for preventing flashover which
are easy to manufacture and incorporate into a candle are
available.
[0018] 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.
[0019] 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.
[0020] 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.
[0021] 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.
[0022] The UL-94 vertical burn test is performed by suspending a
1/2 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 1/4 inch
thick test rod which achieves a V-0 rating qualifies the material
of the test rod used in products in 1/4 or greater thicknesses. The
thinner the test rod, the less combustible the material.
[0023] 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
[0024] It is an object of the present invention to provide a
non-combustible wick holder for a candle to eliminate
flameover.
[0025] 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.
[0026] 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.
[0027] Accordingly, a flame-retardant wick holder for a candle wick
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 is provided extending upwardly from all
around the outer edge of the disc. The barrier has grooves or
through-holes for permitting molten wax to drain off the sloped top
surface of the disc.
[0028] 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.
[0029] 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.
[0030] 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
[0031] In the drawings:
[0032] FIG. 1 is a side sectional view of a prior art candle and
wick holder;
[0033] FIG. 2 is a partial sectional side elevation view of a
candle having a wick holder according to the invention;
[0034] FIG. 3 is a top plan view of the wick holder of FIG. 2;
[0035] FIG. 4 is a partial sectional side elevation view of an
alternative embodiment of the candle and wick holder of FIG. 2;
[0036] FIG. 5 is a sectional top plan view of the wick holder of
FIG. 4;
[0037] FIG. 6 is a top plan view of yet another embodiment of a
candle and wick holder of the invention;
[0038] FIG. 7 is a side elevation view of the wick holder of FIG.
6;
[0039] 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;
[0040] FIG. 9 is a sectional side elevation view of yet another
embodiment of a wick holder of the invention;
[0041] FIG. 10 is a side elevation view of a fifth embodiment of a
wick holder according to the invention;
[0042] FIG. 11 is a sectional side elevation view of the wick
holder of FIG. 10;
[0043] FIG. 12 is a top plan view of the wick holder of FIG.
10;
[0044] FIG. 13 is a side elevation view of an the wick holder of
FIG. 10 with an alternative barrier drain;
[0045] FIG. 14 is a sectional side elevation view of the wick
holder of FIG. 13;
[0046] FIG. 15 is a sectional side elevation view of a sixth
embodiment of a wick holder according to the invention;
[0047] FIG. 16 is a top plan view of the wick holder of FIG.
15;
[0048] FIG. 17 is a sectional side elevation view of an alternate
reservoir of the wick holder of FIG. 15; and
[0049] FIG. 18 is a sectional side elevation view of a second
alternate reservoir of the wick holder of FIG. 15.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0050] 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.
[0051] 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.
[0052] 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.
[0053] 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.
[0054] The sloped upper surface 12, when present, may be formed at
any angle between 0.degree. and 90.degree.. When the upper surface
12 is at 0.degree. or 90.degree. 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.degree. and 30
.degree. angle with a horizontal plane.
[0055] 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.
[0056] FIGS. 4-9 illustrate alternate shapes for the wick holder
10.
[0057] 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.
[0058] 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.
[0059] 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.
[0060] 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.
[0061] The cone-shaped holder of FIG. 9 is preferably at least
about 1/2 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 1/8 inch, and is
preferably between about 1/4 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.
[0062] 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.
[0063] 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 {fraction (1/8)} inch to 1/2 inch. The remaining dimensions
of the wick holder 10 may be the same as in other embodiments.
[0064] 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.
[0065] 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.
[0066] 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.
[0067] The sloped surface 12 can be arranged at any angle from
0-90.degree., relative to horizontal. When the wick holder 10
includes barrier 80, the sloped surface 12 is preferably angled at
between 1-10.degree., and most preferably about 4.degree. relative
to horizontal.
[0068] 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.degree. opposite.
[0069] 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.degree.
apart around the barrier 80.
[0070] In yet another embodiment of the wick holder 10 illustrated
by FIGS. 15-18, the barrier 80 lacks drain holes and forms a
reservoir 400 around bore 18. FIG. 15 shows the wick holder having
a sloped surface 12 which slopes downwardly from bore 18 toward
barrier 80. FIG. 16 displays the arrangement of the bore 18
relative to the sloped surface 12 and barrier 80.
[0071] FIG. 17 illustrates a sloped surface 12 which is angled with
the reverse slope to that of the wick holder 10 of FIG. 15. In FIG.
17, the bore 18 of wick holder 10 extends above sloped surface 12,
so that the reservoir 400 is deepest immediately adjacent the bore
18. As shown, the bore 18 can extend above the edge of barrier 80,
so that even if the wick (not shown in FIG. 17) falls over, there
is additional distance between the wick and molten wax in the
reservoir 400.
[0072] The wick holder 10 may have cavities 90 in the embodiments
of FIGS. 15-18, as shown in FIG. 17, as well to reduce the material
needed to make the wick holder 10.
[0073] FIG. 18 shows the wick holder 10 with the same reverse slope
of sloped surface 12, so that reservoir 400 resembles a bowl, with
bore 18 at the bottom center. This embodiment reduces the size of
the molten wax pool at the end of the candle useful life
surrounding the wick (not shown).
[0074] The embodiment of the wick holder 10 of FIGS. 15-18 is
particularly useful with large-diameter candles. Melted wax pools
within the reservoir 400 when the candle has burned down to the
wick holder 10. But, wax outside the barrier 80 is prevented from
continuing to feed wick 30. Thus, when the wax in the reservoir 400
is consumed below the level of bore 18, the candle will be
extinguished. In the case of a large-diameter candle, when the
barrier 80 has a significantly smaller diameter, it reduces the
amount of pooled wax available to the wick 30 at the end of the
candle useful life to only that pool of wax contained in the
reservoir 400.
[0075] The embodiments of the wick holder 10 having a barrier 80
are particularly useful for preventing secondary wicking. Secondary
wicking occurs when fuel is drawn up from the wax pool through the
free upper end of the wick. If all of the wax pool is drawn up this
way then it is possible to increase the wax pool temperature above
its flash point and/or in a filled candle to break/shatter the
candle holder. To help prevent secondary wicking it is preferable
to make the wick holder 10 about 1.5 inches diameter so that it is
wide enough to prevent the free end of the wick from touching the
wax pool. The barrier 80 provides an elevated support if the upper
end of the wick does fall over, and can prevent it from touching
the pool.
[0076] 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.
[0077] Polyethersulfone melts at about 230.degree. C. (about
446.degree. F.). It has a Vicat softening point of about
215.degree. C. (419.degree. 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.
[0078] Further, PES can appear transparent to yellowish, so that it
is usable in transparent candles.
[0079] 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.
[0080] 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
[0081] Three cylindrical paraffin wax candles and three cylindrical
candles made from UNICLEAR each having a PES wick holder 3/8 inches
in total height, with a 10.degree. 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
[0082] Three cylindrical paraffin wax candles and three cylindrical
candles made from UNICLEAR each having a PES wick holder 3/8 inches
in total height, with a 10.degree. 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
[0083] Three cylindrical paraffin wax candles and three cylindrical
candles made from UNICLEAR each having a PES wick holder 3/8 inches
in total height, with a 20.degree. 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
[0084] Three cylindrical paraffin wax candles and three cylindrical
candles made from UNICLEAR each having a PES wick holder 3/8 inches
in total height, with a 20.degree. 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
[0085] Three cylindrical paraffin wax candles and nine cylindrical
candles made from UNICLEAR each having a PES wick holder 1/4 inches
in total height, with a 10.degree. 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
[0086] Three cylindrical paraffin wax candles and three cylindrical
candles made from UNICLEAR each having a PES wick holder 1/4 inches
in total height, with a 20.degree. 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
[0087] Three cylindrical paraffin wax candles and two cylindrical
candles made from UNICLEAR each having a PES wick holder 1/4 inches
in total height, with a 20.degree. 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.
[0088] In each of the tests above, a 44-32-18c wick from Atkins and
Pierce was used.
[0089] 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 1 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 1/8 inch above the bottom of the
candle or container bottom 22, and preferably between about 1/4
inch and 1 inch above the container bottom 22 or candle bottom.
[0090] 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 1/8 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 1/4 inch are
acceptable.
[0091] 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.
[0092] 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.degree. F. and can also be easily injection molded.
Specific polymers include RADEL A-300, polysulfone P-1720
(pigmented) and polysulfone P-1700, available from Amoco.
[0093] 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.
[0094] A further alternative composition for making the wick holder
10 of the invention is one known commercially as FX-100 sold by
Flame Seal. The composition is formable into any of the wick holder
shapes of FIGS. 2-18. But, the composition does not support
combustion.
[0095] 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.
* * * * *