Note: Descriptions are shown in the official language in which they were submitted.
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Multi-Purpose Gas Lighter with
Ignition-Resistant Function
Inventor: Jong-Koo Jon
BACKGROUND OF INVENTION
1. Field of the Invention:
This invention relates to generally to utility
lighters and more specifically to utility lighters
which contain a safety feature making the lighter
child-resistant.
2. Background Art:
Utility lighters are very useful and have become
quite prevalent in modern times. Utility lighters of
the type described herein generally contain a handle
and an elongated lighting rod. The shape and
operation of utility lighters allow for several
advantages over normal means of producing a flame.
Most significantly, due to the elongated nature of the
3 0 lighting rod, utility lighters enable the operator to
stand a safe distance away from the object to be
ignited before actuating the lighter, thus avoiding a
large number of potential accidents. In addition,
utility lighters allow a flame to be produced in
hard-to-reach or narrow places, where the human hand
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holding a match would not normally fit. Still, in the
hands of children, or others who do not know how to
safely and properly operate the lighter, such lighters
are as dangerous as any other spark and/or flame-
producing device. Therefore, a need has been realized
to equip utility lighters with safety features that
minimize accidental or improper use by inexperienced
persons, especially young children.
Many inventions have been created to address this
safety-related concern. Generally, these inventions
have sought to introduce safety mechanisms that
disable automatic operation of either the spark-
generation and/or the fuel-release function of the
lighter. For example, some utility lighters provide
for a blocking mechanism, where the actuating trigger
(33) (Figs. 6 and 7) is blocked from moving the
required distance for a spark to be generated. In
these lighters, the locking mechanism is normally de-
activated by sliding an "on/off" (32) switch to the
"on" position, or by other means, so as to remove the
impediment from the actuating trigger's operating
path.
Although utility lighters of the type described
above provide some level of safety, there is much room
for improvement. Specifically, in these lighters,
once the locking means (e.g., the on/off switch) is
disabled, the lighter remains in the unlocked state
until the locking mechanism is activated again.
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Therefore, if the operator disables the locking
mechanism in order to use the lighter, and then
forgets to re-lock the lighter, the safety feature of
the lighter is rendered useless, until the locking
mechanism is again activated.
Other inventions have attempted to address the
safety-related issues by impeding, not the operation
of the trigger, but that of the fuel-release
mechanism. Of course, a utility lighter containing
such a mechanism would inhibit flame generation in the
locked position as no fuel would be released until the
locking mechanism has been deactivated. However, in
these types of lighters, nothing prevents a spark from
being generated. As such, the safety goals are only
partially met in these types of lighters since young
children handling the lighter could still create fires
by operating the lighter in close proximity to a
source of fuel or near carpets, paper, or other
flammable material.
In order to address the above problems, some
inventions have introduced locking mechanisms that are
activated automatically after each use of the lighter.
As such, in these lighters, two states of operation
exist: the locked state and the operable state. In
the locked state, neither a spark nor a flame can be
generated. In contrast, in the operable state, the
lighter is no longer locked, so that a flame can be
generated.
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Therefore, there is a need for a device that not
only achieves the stated safety goals in generating a
flame, but also makes it difficult for inexperienced
users and/or young children to sustain the flame. The
invention described herein offers such a combination.
The invention requires that a safety button, protruding
generally from the top portion of the lighter housing
shell, be depressed simultaneously with a trigger before
a flame can be produced.
SUNIlKARY OF THE INVENTION:
The aspect of the present invention is to provide a
safety mechanism for utility lighters so that children or
inexperienced users will be less likely to inadvertently
activate the lighter. Such a safety feature is
especially important because young children often play
with lighters as toys and because lighters have
mechanically moveable parts that make them attractive to
children as toys.
A further aspect of the present invention is to
prevent the generation of not only a flame, but even a
spark. As noted previously, in a lighter where only the
fuel-release mechanism is inhibited in the locked state,
young children playing with the lighter can still
used the lighter to create sparks. Depending on
the child's surroundings, this can lead to the start
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of accidental fires if the child is operating the lighter
near paper products or any other source of flammable
material.
5 Another aspect of the invention described herein is
to provide an improved device for maximizing safety in
utility lighters without compromising ease of use. To
this end, the addition of a safety button creates a
simple additional step which, for the intended user,
leaves the operation of the utility lighter as simple as
it has always been to operate a regular utility lighter
with no safety feature, yet, creates an additional mental
step which acts as a deterrent for non-intended users.
A further aspect of this invention is to reduce the
risk of unintended fires, especially by young children,
by making it impossible for the flame to continue to burn
unless two (2) separate functions are performed
simultaneously and operation of a trigger is continued
without interruption. Furthermore, an aspect of the
present invention is to meet all of its safety goals
while, at the same time, it maximizes ease of
manufacturing and minimizes costs associated with
manufacturing of parts.
The invention provides a
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cam mechanism that integrates several structural
elements. In the preferred embodiment, the cam
mechanism consists of a cam lever, a fuel-release
lever, and a return spring. Most significantly from a
safety standpoint, the cam mechanism contains a cam
lever that acts to lock the trigger in the inoperative
position. Typically, a young child will attempt to
activate the lighter by depressing the trigger only.
However, when this is done, the trigger will not move
at all or significantly, so that neither a spark nor a
1 5 flame will be generated. Since the trigger is locked
in this position, repeated operation of the trigger by
a child will yield the same unsuccessful results.
2 0 The only way to activate the lighter is to depress
the safety button. When this is done, the cam lever
is moved out of the path of the trigger, so that the
trigger can now be depressed. Depression of the
25 safety button also causes the fuel-release lever to
move, so that, depending on the extent of pressure
placed on the safety button, the fuel-release valve
may be opened and fuel released. As such, a second
significant safety-related feature of the present
invention is that a small amoiint of pressure on the
safety button will release the trigger lock. However,
such pressure will not release sufficient fuel for a
flame to be produced. That is, the most that can
happen when the user presses the safety button
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slightly, and then depresses the trigger, is that a
spark would be generated. To ignite the spark, the
user would have to continue pressing the safety button
further than is required to release the lock, so that
sufficient fuel is released before the trigger is
activated and a spark and flame are generated.
The above procedure ensures that even if a child
were to be able to momentarily press the safety button
to release the lock, he or she would still have
trouble creating a flame, as doing so would require
further pressure on the safety button. This is a
simple, yet effective concept. Nevertheless, it is a
concept that a young child operating the lighter must
recognize and grasp before he or she can successfully
operate the lighter. In most cases, the child either
will not recognize the usefulness of the safety button
or, if he/she does, he/she will not be able to
simultaneously press the safety button far enough to
create a flame. As such, the child will most likely
abandon the lighter after several unsuccessful
attempts.
Once the user no longer needs the flame, the
trigger is released. At this point, the return spring
in the cam mechanism ensures that the cam lever, the
fuel-release lever, and the safety button all return
to their original stationary positions, thus also
automatically re-locking the trigger in the inoperable
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state.
As can be understood from the above description,
the invention disclosed herein achieves its safety
objectives without making operation of the lighter any
more cumbersome than a regular utility lighter.
Specifically, the safety button is positioned in such
a way that operation of the lighter is very simple in
experienced hands. An adult user familiar with the
operation of utility lighters still needs to use only
one finger to sustain the flame. This allows the user
to operate the lighter in a safe, yet non-complicated
manner.
2 0 The unique structure of the cam mechanism contained
in the present invention provides for an optimum
amount of safety as it makes it very difficult, if not
impossible, for young children to operate the device.
Young children are capable of carrying out only simple
mental concepts. As such, a young child wishing to
operate the present invention would attempt do so in
the usual way, i.e., by pressing the trigger.
However, due to the automatic locking mechanism of the
device, the trigger will not move. This alone will
act as a deterrent as most young children will simply
abandon the device after several unsuccessful
attempts. This is true because a child operator must
first recognize that both the trigger and the safety
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9
button must be operated simultaneously before a flame
can be generated. This is generally too convoluted a
concept for young children to grasp or appreciate.
Nevertheless, even if a young child were to be able
to learn the proper operation of the device, he or she
would probably still be unable to actually operate the
device. Given the relative location of the trigger
and the safety button, operation of the present
invention requires that the user be able to grasp the
handle of the lighter in his or her hand, operate the
trigger with the index finger, and simultaneously
operate the safety button with the thumb. This, in
turn, requires not only a significant amount of manual
dexterity, but also hands that are sufficiently large,
namely, adult hands. Moreover, successful operation
of the device requires an amount of strength and pulp
that are rarely found in the fingers of young
children.
In addition, even if a child were to possess the
mental capacity for understanding and learning the
required process of operation, a large enough hand,
and the required amount of manual dexterity, strength,
and pulp, so that he or she could somehow generate a
flame, he or she would have to recognize a second
concept: that the flame will not be sustained unless
the trigger is held in its activated state. Again,
this is a difficult mental concept for a child to
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recognize and learn. Moreover, even if learned, the
concept would be difficult for a child to operationalize
given the above discussion regarding the mental and
physical limitations of young children. On the other
5 hand, an adult user would have no difficulty operating
the invention as the device requires no more than the
simultaneous operation of two strategically positioned
buttons.
In addition to all of the safety advantages
10 described above, the invention described herein offers a
significant reduction in cost, and a significant
increase in ease, of manufacturing. The cam mechanism
is an integrated, one-piece member that performs the
functions of at least three (3) separate members in most
other utility lighters currently available on the
market. Moreover, the entire safety feature, as well as
full operation of the devise is generally enabled by the
manufacture and use in the lighter of two (2) basic
elements: the cam mechanism and the safety button. In
addition, it is contemplated that these two elements may
even be combined, so that only one integrated structural
member need be produced. This, of course, would lead to
even more significant savings and simplicity in the
manufacturing process.
Accordingly, one aspect of the invention resides in
a utility lighter having a lighter housing, a lighting
rod projecting from the lighter housing, a gas tank
located within the lighter housing having a fuel release
valve connected to a gas tube that extends through the
lighting rod, and a piezo unit capable of igniting fuel
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released from said tank, the improvement comprising: a
trigger and a safety button at least partially contained
within said lighter housing, said safety button having an
operational end capable of engaging said trigger and said
release valve; said trigger being slideably mounted in
said lighter housing; said safety button and said trigger
capable of operating said release valve in unison when
said safety button and said trigger are depressed at the
same time; and, when said safety button is in an
undepressed position, said operational end of said safety
button blocks said trigger from activating said release
valve.
In another aspect, the invention resides in a
utility lighter having a lighter housing, a lighting rod
projecting from the lighter housing, a gas tank located
within the lighter housing having a fuel release valve
connected to a gas tube that extends through the lighting
rod, and a piezo unit capable of igniting fuel released
from said tank, the improvement comprising: a trigger
and a safety button at least partially contained within
said lighter housing, a cam mechanism independently
actuable by said safety button and having at least two
projections extending in different directions, said two
projections being a fuel-release lever for engaging said
valve and a cam lever for interfering with movement of
said trigger; said safety button biased in a locked
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lOb
position wherein said cam lever is positioned to
interfere with said trigger and said safety button
capable of being moved to an unlocked position that
causes said cam lever to move out of interference with
said trigger and said fuel-release lever to open said
valve; and, said trigger being capable of engaging said
piezo unit whereby fuel is ignited when said trigger and
said safety button are operated simultaneously.
This and other advantages of the present invention
will become more apparent through the following
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description of the drawings and detailed description
of the preferred embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS:
Fig. 1 is a perspective view of the preferred
embodiment of the invention;
Fig. 2 is a sectional view of the preferred
embodiment of the invention;
Fig. 3 is an exploded view of the preferred
embodiment;
Fig. 4 is a cross-sectional view of the preferred
embodiment;
Fig. 5 is a cross-sectional view of the preferred
embodiment during operation;
Fig. 6 is a perspective view of a prior art
lighter; and
Fig. 7 is a cross-sectional view of a prior art
lighter.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT:
A general description of the piezoelectric utility
lighter (1) (Fig. 1) will be provided before
presenting a detailed description of the improvement
in the safety feature that constitutes the invention.
Generally, the elements of the utility lighter (1)
include a lighter housing (10), a lighting rod (16)
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attached to the forward end of the lighter housing via
engagement means (not shown), a support ring which
slides over the overlapping portions of the lighter
housing and lighting rod, a fuel tank (30) (Figs. 2
and 3), a piezoelectric unit (40), a cam-support pin
(50), a cam mechanism (60), a fuel-release lever (70),
a cam lever (80), a return spring (90), a trigger
(100), a stopper (110), and a safety button (120).
The lighter housing (10) is comprised of two
shells, cut along the longitudinal axis of the lighter
(1). The lighter housing (10) has a back end and a
forward end, where the forward end is equipped with
engagement means (not shown) to engage a lighting rod
(16). The lighting rod, which typically has a
cylindrical cross section, has a free end which
constitutes the tip of the- lighter (1) and an
engagement end which connects to the forward end of
the lighter housing. Where the forward end of the
lighter housing and the engagement end of the lighting
rod overlap, there is provided a support ring (not
shown) which slides over and maintains the lighter
housing-lighting rod combination.
The lighter (1) is equipped with a fuel tank (30).
A fuel-release valve (31) is attached to the fuel
tank. This valve is spring loaded so that it is
normally urged to the closed position. The valve is
also provided with a gas tube (32) which extends
through the lighting rod and to a discharge nozzle
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(not shown) at the free end of the lighting rod. The
valve is opened via the operation of a fuel-release
lever (70).
The next element of the lighter (1) is a
piezoelectric unit (40). The upper section of the
piezoelectric unit (40) constitutes the sliding
section (41). The sliding section (41) has a contact
surface (42) that is in contact the trigger (100).
Operation of the piezoelectric unit (40) creates an
electric discharge that is carried to the free end of
1.5 the lighting rod via a wire (not shown).
One of the primary elements of the safety-related
invention is a cam mechanism (60). The cam mechanism
has a hub (61), as well as three projections that
extend in generally different directions. These
projections are: a fuel release lever (70), a cam
lever (80), and a return spring (90).
The cam mechanism is held in place by a cam-support
pin (50). The cam-support pin (50) is a projection
that extends from the inner surface of one of the
lighter housing shells in a direction that is
perpendicular to the longitudinal axis of the lighter
(1). The hub (61) of the cam mechanism (60) fits unto
and is supported by the cam-support pin (50).
The fuel-release lever (70) is connected to the
valve (31) by a C-shaped notch (71) in the fuel
release lever, and has an opposing end that is
integral with the hub (61) of the cam mechanism (60).
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The cam lever (80) has one end that is integral with
the hub (61) of the cam mechanism (60) and an opposing
free end that constitutes the cam-lever edge (81).
The return spring (90) also has one end that is
integral with the hub (61) of the the cam mechanism
(60).
The next primary element is the trigger (100). The
trigger (100) is slidably mounted between the two
shells of the lighter housing (10). As in
conventional utility lighters, the trigger (100) is
allowed to slide back and forth along the longitudinal
axis of the lighter (1). The trigger (100) has an
operation section (101) that protrudes from the
lighter housing (10) so as to be operated by a finger
of the user. Generally, the operation section (101)
has a surface that is slightly curved so as to appear
concave. However, the invention described herein is
2.5 amenable to different degrees of curvature for the
operation section (101) of the trigger (100).
The trigger (100) also has an undersurface that
makes contact with the contact surface (42) of the
sliding section (41) of the piezoelectric unit (40).
In addition, the trigger (100) has a trigger tab (103)
and a stopper tab (110). The trigger tab (103) is a
projection that makes contact with the upper surface
of the cam lever (80). The stopper tab (110) is
typically placed underneath the trigger tab (103) and
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engages the cam-lever edge (81).
The next primary element is a safety button (120).
The safety button (120) is slidably fitted within the
5 top surface of the lighter housing shell and has an
operation section (121). The safety button is
integral with the cam lever (80), and the safety
button is connected substantially at a midpoint of the
cam lever. The safety button (120) has a C-shaped
notch (122), which allows the fuel tube to pass by the
safety button
In the preferred embodiment, the primary elements
of the safety-related invention described herein, as
well as the interaction between these and the other,
more conventional, elements of the utility lighter can
be further defined as follows.
In the preferred embodiment, the hub (61) (Figs. 4
and 5) of the cam mechanism (60) is fitted unto and
supported by the cam-support pin (50), so that the hub
(61) is capable of rotating around the cam-support pin
(50). In order to operate the lighter (1), the user
must press the trigger (100) to create a spark, and
release fuel so that a flame can be generated.
However, when the user attempts to press the trigger
(100), the trigger will not move significantly or at
all.
In the inoperable state, the trigger tab (103) is
in contact with the upper surface of the cam lever
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(80). The trigger (100) has a stopper tab (110) that
engages the cam-lever edge (81). This acts as a
locking mechanism which must be released before the
trigger can be moved. To release the lock, the user
must press the safety button (120) by pushing on the
safety button operation section (121). When the safety
button (120) is depressed, the motion of the safety
button (120) is translated to the cam lever (80)
disengaging the cam-lever edge (81) from the stopper
tab (110), and resistance is provided by the return
spring (90).
The cam lever (80) moves, so that its cam-lever
edge (81) is disengaged from the stopper tab (110),
once they are disengaged the trigger (100) can be
pulled. Once the trigger is pulled the cam-lever edge
contacts the inclined surface (111), and as.the cam-
lever edge moves along the inclined surface, the cam
mechanism continues to rotate and opens the fuel-
release valve (31).
With the locking mechanism disengaged, the user can
now press the trigger (100) in order to create a
spark. As the operation section (101) of the trigger
(100) is pushed, the undersurface (102) of the trigger
(100) contacts the contact surface (42) of the sliding
section (41) of the piezoelectric unit (40). In this
way, as the trigger (100) is activated, so is the
piezoelectric unit (40), so that a spark is generated
when the sliding section (41) has moved back far
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enough.
This, in turn, causes further rotation of the hub
(61), which causes the fuel-release lever (70) to open
the fuel-release valve (31) and release fuel. Once
the flame is no longer needed, the trigger (100) is
released. This allows both the cam lever (80) and the
fuel-release lever (70) to return to their stationary
positions under the urging influence of return spring
(90). Once in this position, the cam-lever edge (81)
again engages the stopper tab (110), thereby
automatically re-locking the lighter.
25
35
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