U.S. patent application number 09/751628 was filed with the patent office on 2001-09-20 for child-resistant utility lighter incorporating a cam mechanism and a lever spring lock.
Invention is credited to Sung, Kil Yong.
Application Number | 20010023054 09/751628 |
Document ID | / |
Family ID | 27383393 |
Filed Date | 2001-09-20 |
United States Patent
Application |
20010023054 |
Kind Code |
A1 |
Sung, Kil Yong |
September 20, 2001 |
Child-resistant utility lighter incorporating a cam mechanism and a
lever spring lock
Abstract
A safety mechanism of a utility lighter. In a first preferred
embodiment, the safety mechanism includes a safety button and a cam
mechanism having a fuel release lever, a cam lever, and a return
spring. When the cam mechanism is in the locked position, the cam
lever engages the stopper tab of the trigger to impede depression
of the trigger, and the fuel release lever closes the fuel release
valve. The cam mechanism is actuated by depressing the safety
button. As the safety button is depressed, the cam lever is
disengaged out of alignment with the stopper tab to permit
depression of the trigger, the hub rotates, and the fuel release
lever is actuated to open the fuel-release valve. As the safety
button is released, the return spring urges the cam mechanism into
the locked position. In a second preferred embodiment, the safety
mechanism includes a lever spring and the cam mechanism having the
fuel release lever and the safety button. When the cam mechanism is
in the locked position, the lever spring engages the stopper tab to
impede depression of the trigger, and the fuel release lever closes
the fuel release valve. The cam mechanism is actuated by depressing
the safety button. As the safety button is depressed, the lever
spring is disengaged out of alignment with the stopper tab to
permit depression of the trigger, the hub rotates, and the fuel
release lever is actuated to open the fuel-release valve. As the
safety button is released, the lever spring urges the cam mechanism
into the locked position.
Inventors: |
Sung, Kil Yong; (Fullerton,
CA) |
Correspondence
Address: |
TROJAN LAW OFFICES
9250 WILSHIRE BLVD
SUITE 325
BEVERLY HILLS
CA
90212
|
Family ID: |
27383393 |
Appl. No.: |
09/751628 |
Filed: |
December 30, 2000 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
09751628 |
Dec 30, 2000 |
|
|
|
09531082 |
Mar 18, 2000 |
|
|
|
6168420 |
|
|
|
|
60126326 |
Mar 26, 1999 |
|
|
|
Current U.S.
Class: |
431/153 ;
431/255 |
Current CPC
Class: |
F23Q 2/287 20130101;
F23Q 2/164 20130101 |
Class at
Publication: |
431/153 ;
431/255 |
International
Class: |
F23D 011/36; F23Q
007/12; F23Q 007/24 |
Claims
I claim:
1. A safety mechanism for a utility lighter, the utility lighter
comprising a lighter housing, a lighting rod projecting from the
lighter housing, a fuel tank, located within the lighter housing,
for holding the fuel, a fuel-release valve being spring loaded so
as to be urged into the closed position, a gas tube connected to
the valve and extending through the lighting rod, and a
conventional piezoelectric unit for creating a spark, said safety
mechanism comprising: a trigger, slidably mounted in the lighter
housing, for activating the piezoelectric unit, the trigger having
a stopper tab; a lever spring having an engaged position and a
disengaged position, the lever spring being aligned with the
stopper tab in the engaged position for impeding depression of the
trigger; a cam mechanism having an actuated position, a locked
position, a cam support pin, projecting from the lighter housing,
for mounting the hub, and a hub, the hub having two projecting
members, the projecting members being a fuel-release lever and a
safety button, the fuel-release lever is attached to the
fuel-release valve, and opens the fuel-release valve, the safety
button having a top end and a bottom end, the top end protruding
through the lighter housing and the bottom end being attached to
the hub, depressing the safety button depresses the lever spring
and rotates the hub, as the lever spring is depressed the lever
spring is not aligned with the stopper tab and the trigger can be
depressed, as the cam mechanism rotates the fuel-release lever
translates opening the fuel-release valve, as the safety button is
released the lever spring urges the cam mechanism into the locked
position.
2. The safety mechanism of claim 1, further comprising a safety
button stop, projecting from the lighter housing, for limiting the
distance the safety button can be depressed.
3. The safety mechanism of claim 1, wherein the second end of the
safety button is attached to the hub.
4. The safety mechanism of claim 1, wherein the trigger is shaped
to receive a finger.
5. The safety mechanism of claim 1, wherein the lever spring is
comprised of a flexible material.
6. A safety mechanism for a utility lighter, the utility lighter
comprising a lighter housing, a lighting rod projecting from the
lighter housing, a fuel tank, located within the lighter housing,
for holding the fuel, a fuel-release valve being spring loaded so
as to be urged into the closed position, a gas tube connected to
the valve and extending through the lighting rod, and a
conventional piezoelectric unit for creating a spark, said safety
mechanism comprising: a trigger, slidably mounted in the lighter
housing, for activating the piezoelectric unit, the trigger having
a stopper tab; a hub mounted to the lighter housing; a fuel-release
lever having a first end and a second end, the first end being
attached to the hub and the second end being attached to the
fuel-release valve, the fuel-release lever having an opened
position and a closed position, while in the opened position the
fuel-release lever opens the fuel-release valve, while in the
closed position the fuel-release valve is closed; a lever spring,
adjacent to the stopper tab of the trigger for locking the trigger,
the lever spring having an engaged position and a disengaged
position, when the lever spring is in the engaged position the
trigger cannot be depressed because the lever spring is aligned
with the stopper tab, when the lever spring is in the disengaged
position the trigger can be depressed because the lever spring is
not aligned with the stopper tab; a safety button having a top end
and a bottom end, the top end protrudes through the lighter
housing, as the safety button is depressed the lever spring is
depressed and the hub rotates, as the lever spring is depressed the
lever spring is not aligned with the stopper tab and the trigger
can be depressed, as the hub rotates the fuel-release lever
translates opening the fuel-release valve, as the safety button is
released the lever spring returns to the disengaged position.
7. The safety mechanism of claim 6, further comprising a safety
button stop, projecting from the lighter housing, for limiting the
distance the safety button can be depressed.
8. The safety mechanism of claim 6, wherein the bottom end of the
safety button is attached to the hub.
9. The safety mechanism of claim 6, wherein the trigger is shaped
to receive a finger.
10. The safety mechanism of claim 6, wherein the lever spring is
comprised of a flexible material.
Description
RELATED PATENT APPLICATIONS
[0001] This application claims priority to a U.S. patent
application Ser. No. 09/507,100, filed Feb. 17, 2000 which claims
priority to provisional application Ser. No. 60/126,326, filed Mar.
26, 1999.
BACKGROUND OF INVENTION
[0002] 1. Field of Invention
[0003] This invention relates to a utility lighter which contains a
safety feature incorporating a cam mechanism and a safety button,
wherein normal operation of the lighter through depression of the
trigger is impeded by the safety feature, and wherein operation of
both the safety button and the trigger will produce a flame.
[0004] 2. Background Art
[0005] 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 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 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.
[0006] 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 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" switch to the "on" position, or by other means, so as to
remove the impediment from the actuating trigger's operating
path.
[0007] 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. 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.
[0008] 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.
[0009] 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. Although, in general,
this improvement has alleviated some of the concerns mentioned
above, there is still room for further improvement. Specifically,
in most dual-state, automatic-locking lighters, once the lighter is
unlocked and the trigger activated, the flame that is generated
will subsist for as long as the trigger is held in the depressed
position. In other words, once the locking mechanism is disabled,
flame generation is a simple task involving depression of the
trigger. This is of some concern since even young children might be
able to achieve this task.
[0010] 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. In addition, the invention requires that the
safety button, and not necessarily the trigger, be held in its
activated state in order for the flame to be sustained; releasing
the safety button after simultaneous activation of both the safety
button and the trigger will cause the flame to be extinguished.
[0011] 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 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.
[0012] 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.
[0013] In addition, even if a child were to posses 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 safety
button is held in its activated state. Again, this is a difficult
mental concept for a child to 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 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.
[0014] In addition to all of the safety advantages 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 can perform the
functions of two (2) or 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 device 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.
SUMMARY OF THE INVENTION
[0015] The primary object of this 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.
[0016] Another object 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 use the lighter to create sparks. Depending on
the child's surroundings, this can lead to the start of accidental
fires if the child is operating the lighter near paper products or
any other source of flammable material.
[0017] A further object 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.
[0018] Another object 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
safety button is continued without interruption.
[0019] A final object 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.
[0020] The invention meets its objectives by providing a cam
mechanism that integrates several structural elements. In a first
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.
[0021] In a second preferred embodiment, the safety mechanism
consists of a cam mechanism and a lever spring. The cam mechanism
consists of a fuel-release lever and a safety button. The lever
spring locks the trigger in the inoperative position.
[0022] 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 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.
[0023] The only way to activate the lighter is to depress the
safety button. In the first preferred embodiment, depressing the
safety button moves the cam lever out of the path of the trigger,
so that the trigger can now be depressed. In the second preferred
embodiment, depressing the safety button moves the lever spring out
of the path of the trigger, so that the trigger can now be
depressed.
[0024] Depression of the 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 amount 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 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.
[0025] 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.
[0026] Once the intended operator has pressed the safety button far
enough to both unlock the trigger and provide adequate fuel
release, the operator then presses the trigger in order to generate
a flame. However, to sustain the flame, the operator must continue
to hold the safety button in its activated position. This is a
significant departure from lighters that are currently in the
market. In most lighters currently in use, once a flame is
generated by depressing a trigger, the flame will subsist for as
long as the operator continues to hold the trigger in its activated
position. In contrast, in the present invention, the cam mechanism
allows separation of fuel-release on the one hand, and spark
generation on the other, so that spark generation will not
necessarily lead to the production of a sustained flame.
[0027] It follows that, to successfully operate the present
invention, the user must recognize that, once a flame has been
generated, it is the safety button, and not the ignition trigger,
that must be held in the activated position. This is another
procedural step which creates a mental concept that is simple for
the adult user to grasp and practice, but difficult for young
children to either grasp or practice.
[0028] In the first preferred embodiment, once the user no longer
needs the flame and the safety button is released, the return
spring in the cam mechanism ensures that the cam lever, the
fuel-release lever, and the safety button return to their original
stationary positions, thus also automatically re-locking the
trigger in the inoperable state. In the second preferred
embodiment, the lever spring ensures that the fuel-release lever
and the safety button all return to their original stationary
positions when the safety button is released, thus also
automatically re-locking the trigger in the inoperable state.
[0029] 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.
[0030] This and other advantages of the present invention will
become more apparent through the following description of the
drawings and detailed description of the preferred embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1 is a sectional view showing an embodiment of a
child-resistant utility lighter according to the first preferred
embodiment; and
[0032] FIG. 2 is a sectional view showing an embodiment of a
child-resistant utility lighter according to the second preferred
embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0033] A general description of the piezoelectric utility lighter
(1) will be provided before presenting a detailed description of
the improvement in the safety feature that constitutes the
invention.
[0034] Generally, the elements of the utility lighter (1) include a
lighter housing (10), a lighting rod 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 (not shown), a fuel tank (30), a
piezoelectric unit (40), and a trigger (100).
[0035] The lighter housing (10) is comprised of two shells, cut
along the longitudinal axis of the lighter (1). FIGS. 1 and 2 show
one of these shells. The lighter housing (10) has a back end (10a)
and a forward end (not shown), where the forward end is equipped
with engagement means (not shown) to engage the lighting rod (not
shown). 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.
[0036] The lighter (1) is equipped with a fuel tank (30) near the
back end (10a) of the lighter housing (10). The fuel tank (30) has
a bottom portion (30a) facing the back end (10a) of the lighter
housing, and a top portion (30b) pointing towards the forward end
of the lighter housing. A fuel-release valve (31) is attached to
the top portion (30b) of 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 (not shown) at the free end
of the lighting rod. The valve is opened via the operation of a
fuel-release lever (70). Finally, a flame-adjusting knob (33) is
provided on the valve (31) which can be turned to adjust the amount
of fuel released and, thus, the height of the resultant flame.
[0037] The next element of the lighter (1) is a piezoelectric unit
(40). This unit is fitted within the top portion (30b) of the fuel
tank and protrudes from said top portion. 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
with an undersurface (102) of trigger (100). Operation of the
piezoelectric unit (40) creates an electric discharge that is
carried to the free end of the lighting rod via a wire (not
shown).
[0038] One of the primary elements of the first preferred
embodiment (FIG. 1) 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).
[0039] The hub (61) is held in place by a cam-support pin (50). The
cam-support pin is a projection that extends from the inner surface
of one of the lighter housing shells (10) in a direction that is
perpendicular to the longitudinal axis of the lighter (1). The hub
fits onto and is supported by the cam-support pin.
[0040] The fuel-release lever (70) has one end (71) that is located
between the valve (31) and the flame-adjusting knob (33), and an
opposing end that is integral with the hub (61) of the cam
mechanism (60).
[0041] 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 cam lever also has an
upper surface (82), a lower surface (83), and a cavity (84). The
cavity (84) houses a safety-button pin (123) of a safety button
(120).
[0042] The return spring (90) also has one end that is integral
with the hub (61) of the cam mechanism (60) and an opposing free
end (91). The return spring further consists of an upper surface
(92) and a lower surface (93), where the lower surface rests on a
projection (15) that is fixedly attached to the inner surface of
one of the lighter housing shells (10).
[0043] The next primary element of the first preferred embodiment
is the trigger (100). The trigger is slidably mounted between the
two shells of the lighter housing (10). As in conventional utility
lighters, the trigger is allowed to slide back and forth along the
longitudinal axis of the lighter (1). The trigger 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 amenable to
different degrees of curvature for the operation section (101) of
the trigger.
[0044] The trigger (100) also has an undersurface (102) that makes
contact with the contact surface (42) of the sliding section (41)
of the piezoelectric unit (40). In addition, the trigger (100) is
integral with a trigger tab (103) and a stopper tab (110). The
trigger tab (103) is a projection that makes contact with the upper
surface (82) of the cam lever (80). The stopper tab (110) is
typically placed underneath the trigger tab (103) and has a contact
edge (111) that engages the cam lever edge (81).
[0045] The next primary element of the first preferred embodiment
is a safety button (120). The safety button (120) is slidably
fitted within the top surface of the lighter housing shell and has
an operation section (121) that protrudes from this top surface.
The safety button has a lower surface (122) that is integral with a
safety-button pin (123), which pin (123) is in contact with the cam
lever (80) via the cavity (84) in said cam lever. The safety button
(120) is also integral with a set of flanges (124) that can make
contact with the inner portion of the top surface of the lighter
housing shell, thus limiting the range of motion of the safety
button (120).
[0046] In the first preferred embodiment (FIG. 1), 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.
[0047] In the first preferred embodiment, the hub (61) of the cam
mechanism (60) is fitted onto 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.
[0048] In the inoperable state, the trigger tab (103) is in contact
with the upper surface (82) of the cam lever (80). The trigger
(100) is integral with a stopper tab (110) whose contact edge (111)
engages the cam-lever edge (81) of the cam lever (80). 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) via the
safety-button pin (83) as resistance is provided by the return
spring (90) pressing against the projection (15).
[0049] Initially, the cam lever (80) moves, so that its cam-lever
edge (81) is disengaged from the contact edge (111) of the stopper
tab (110). In addition, the initial pressing of the safety button
(120) will cause the fuel-release lever (70) to also move slightly.
However, this movement will be insufficient to release an amount of
fuel that is adequate for flame production.
[0050] 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 enough.
[0051] Without more, the operational procedure described above will
only produce a spark. In order to produce a flame, the operator
must continue to push the safety button (120), thereby further
moving the cam lever (80). 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. Now, with the safety
button (120) held in this position, depression of the trigger (100)
will allow a flame to be generated.
[0052] Once a flame has been generated, it can be sustained only if
fuel continues to be supplied. As explained above, this will only
occur if the safety button (120) is held in position and not
released after a flame has been generated. Simply holding the
trigger (100) in the activated state will not sustain the flame.
That is, even though, after the lighter has been unlocked,
depression of the trigger (100) might cause the upper surface (82)
of the cam lever (80) to be held underneath the bottom surface of
the stopper tab (110), the hub (61) of the cam mechanism (60) has
not rotated enough at this point for the fuel-release lever (70) to
be able to move and sufficiently open the fuel-release valve
(31).
[0053] Once the flame is no longer needed, the safety button (120)
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 contact edge
(111) of the stopper tab (110), thereby automatically re-locking
the lighter. Finally, as the safety button (120) moves to its
stationary position, it is stopped in that position when flanges
(124) reach the inner portion of the top surface of the lighter
housing shell.
[0054] In the second preferred embodiment (FIG. 2), one of the
primary elements of the lighter is the cam mechanism (60). The cam
mechanism (60) has a hub (61) and two projections: a fuel-release
lever (70) and a safety button (120).
[0055] The cam mechanism (60) is held in place by a cam-support pin
(50). The cam-support pin is a projection that extends from the
inner surface of one of the lighter housing shells (10) in a
direction that is perpendicular to the longitudinal axis of the
lighter (1). The hub (61) of the cam mechanism (60) fits onto and
is supported by the cam-support pin.
[0056] The fuel-release lever (70) has one end (71) that is located
between the valve (31) and the flame-adjusting knob (33), and an
opposing end that is integral with the hub (61) of the cam
mechanism (60).
[0057] The safety button (120) is slidably fitted within the top
surface of the lighter housing shell (10) and has an operation
section (121) that protrudes from this top surface. The safety
button has a safety button projection (151) that contacts the lever
spring (150). The safety button has a lower portion (122) that is
integral with the hub (61). A safety button stop (152) limits the
downward range of motion of the safety button. The safety button
stop is a projection that extends from the inner surface of one of
the shells in a direction that is perpendicular to the longitudinal
axis of the lighter (1).
[0058] The next primary element of the second preferred embodiment
is the lever spring (150). The lever spring has one end that
constitutes a lever spring edge (112) and an opposing end that is
fixed to a spring projection (15) that is fixedly attached to the
inner surface of one of the lighter housing shells.
[0059] The next primary element of the second preferred embodiment
is the trigger (100). The trigger is slidably mounted between the
two shells of the lighter housing (10). As in conventional utility
lighters, the trigger is allowed to slide back and forth along the
longitudinal axis of the lighter (1). The trigger has an operation
section (101) that protrudes from the lighter housing so as to be
operated by a finger of the user. Generally, the operation section
has a surface that is slightly curved so as to appear concave.
However, the invention described herein is amenable to different
degrees of curvature for the operation section of the trigger.
[0060] The trigger (100) also has an undersurface (102) that makes
contact with the contact surface (42) of the sliding section (41)
of the piezoelectric unit (40). In addition, the trigger is
integral with a trigger tab (103) and a stopper tab (110). The
trigger tab is a projection that makes contact with the upper
surface of the lever spring (150). The stopper tab is typically
placed underneath the trigger tab and has a contact edge (111) that
engages a lever spring edge (112).
[0061] In the second preferred embodiment (FIG. 2), 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 lighter can be further defined as follows:
[0062] In the second preferred embodiment, the hub (61) of the cam
mechanism (60) is fitted onto and supported by the cam-support pin
(50), so that the hub 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, the trigger will not move significantly or at all.
[0063] When the lighter is in the locked position, the trigger tab
(103) is in contact with the upper surface of the lever spring
(150), and the contact edge (111) of the stopper tab (110) engages
the lever spring edge (112). Engagement of these edges acts as a
locking mechanism which must be released before the trigger can be
moved. To release the lock, the user must depress the safety button
(120) by depressing the safety button operation section (121) of
the safety button. When the safety button is depressed, the motion
of the safety button is translated to the lever spring via the
safety-button projection (152) as resistance is simultaneously
provided by the flexing of the lever spring (150).
[0064] Initially, the lever spring (150) moves, so that its lever
spring edge (112) is disengaged from the contact edge (111) of the
stopper tab (110). In addition, the initial depression of the
safety button (120) will cause the fuel-release lever (70) to also
move slightly. However, this movement will be insufficient to
release an amount of fuel that is adequate for flame
production.
[0065] 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 is pushed, the undersurface
(102) contacts the contact surface (42) of the piezoelectric unit
(40). In this way, as the trigger is activated, so is the
piezoelectric unit, so that a spark is generated when the sliding
section (41) has moved back far enough.
[0066] Without more, the operational procedure described above will
only produce a spark. In order to produce a flame, the operator
must continue to push the safety button (120), thereby causing
further rotation of the hub (61), which causes the fuel-release
lever (70) to open the fuel-release valve (31) and release fuel.
The safety button stop (152) limits the distance the safety button
can be depressed. Now, with the safety button (120) held in this
position, depression of the trigger (100) will allow a flame to be
generated.
[0067] Once a flame has been generated, it can be sustained only if
fuel continues to be supplied. As explained above, this will only
occur if the safety button (120) is held in the depressed position
and not released after a flame has been generated. Holding the
trigger (100) in the activated state alone will not sustain the
flame.
[0068] Once the flame is no longer needed, the safety button (120)
is released. This allows the fuel-release lever (70) to return to
its stationary position under the urging influence of the lever
spring (150). Once in this position, the lever spring edge (112)
again engages the contact edge (111) of the stopper tab (110),
thereby automatically re-locking the lighter.
* * * * *