US20100216081A1

US20100216081A1 - Bar lighter comprising a safety mechanism

Info

Publication number: US20100216081A1
Application number: US11/917,925
Authority: US
Inventors: Peter Huang
Original assignee: Pi Design AG
Current assignee: Pi Design AG
Priority date: 2005-06-23
Filing date: 2006-05-29
Publication date: 2010-08-26
Also published as: EP1893916A1; CA2613456A1; AU2006261558A1; WO2006136039A1

Abstract

Disclosed is a bar lighter comprising a novel safety mechanism for securing the bar lighter from being accidentally actuated. A safety lever (4) is pivotally connected to an actuating element (2) which can be moved relative to a housing between a starting position and an actuating position. Said safety lever (4) is preloaded so as to be pressed into a locking position in which the safety lever (4) engages with a locking element (15) that cannot be moved relative to the housing, thus preventing the actuating element (2) from moving from the starting position into the actuating position. A releasing mechanism (3) is provided which presses the safety lever (4) into a releasing position when being actuated so as to release the actuating element (2).

Description

TECHNICAL FIELD

The present invention relates to a lighter, in particular a so-called stick lighter (bar lighter), having the features of the preamble of Claim 1.

PRIOR ART

A stick lighter is understood as meaning a specific configuration of a gas lighter which is particularly suitable for igniting candles, gas flames in cookers, chimneys, grills, etc. For this purpose, a stick lighter has a housing with a longitudinally extending, often rod-like front region. A tank for a fuel, usually a liquefied lighter gas such as a propane/butane mixture, and an actuating mechanism are arranged in the rear region of the housing. A fuel line is led from the tank to the front end of the housing, where an igniting device, e.g. a piezoelectric igniter, is located. As long as the actuating mechanism is not activated, the mechanism interrupts the supply of fuel through the fuel line. Upon actuation of the actuating mechanism, fuel is led through the fuel line to the front end and is ignited there by the igniting device. In this way, a flame is produced at this end. A stick lighter is also occasionally referred to as a utility lighter or chimney lighter.
There is a need for stick lighters to be protected by a safety mechanism against undesired or unauthorized use, e.g. by a child at play. Various safety mechanisms have been proposed, e.g. in U.S. Pat. No. 5,697,775. The lighter here has a locking element in addition to an actuating element. The actuating element is designed in each case in the manner of a trigger of a handgun, i.e. it is actuated, by pulling with the index finger, in a direction away from the front end of the lighter. The safety mechanisms which are proposed for this purpose can only be used for lighters in which the actuating element is actuated in the manner of a gun trigger. They are of relatively complex construction and, in some cases, require a considerable amount of space. In addition, these mechanisms have the risk of, the locking element getting caught in a position in which it permanently releases the actuating element, as a result of which the safety mechanism would be rendered permanently inoperative.
U.S. Pat. No. 6,669,466 discloses a stick lighter of which the safety mechanism comprises a button which is arranged on a side of the housing which is located opposite an actuating slide. A locking element is connected to the button. The locking element has a main portion which extends in the direction of the actuating slide and from which a guide flange extends in the direction of the rear end of the housing. When the button is located in its starting position, the guide flange blocks the actuating slide. When, in contrast, the button is pushed, the guide flange releases the actuating slide. Since the main portion and the guide flange are relatively delicate, there is a risk, with this design, of the locking element breaking, as a result of which the safety mechanism would become inoperative.

DESCRIPTION OF THE INVENTION

It is thus an object of the present invention to provide a lighter which is reliably safeguarded on a permanent basis against undesired actuation, which, while having a highly stable safety mechanism, is nevertheless compact and, in particular, can be produced with a low overall height, and of which the safety device is of simple construction.
This object is achieved by a lighter according to Claim 1. Advantageous configurations are specified in the dependent claims.
A lighter according to the invention thus comprises:

- a housing with a proximal end and a distal end,
- an actuating device, which comprises an actuating element which can be displaced relative to the housing, counter to an actuating force, between a starting position and an actuating position, wherein the actuating device, in the starting position, prevents fuel from being supplied to the distal end of the housing and, in the actuating position, releases the supply of fuel, and
- a safety device, in order to prevent accidental displacement of the actuating element.

The safety device comprises a safety lever which is connected to the actuating element and is pivotable relative to the actuating element between a locking position and a release position. The safety lever, in the locking position, is in engagement with a locking element which is stationary relative to the housing and thus prevents the actuating element from moving from the starting position into the actuating position. Biasing (preloading) means are present, and these push the safety lever, counter to a biasing force, into the locking position. In order to allow actuation of the lighter, a release device is provided, and this can be moved between a rest position and an activated position, wherein the release device, in the activated position, pushes the safety lever, counter to the biasing force of the biasing element, into the release position.
By virtue of the safety lever being articulated on the actuating element, locking of the actuating element is achieved in a particularly straightforward manner. Both the safety lever and the locking element may be designed in a straightforward, and therefore very robust, manner. There is no need for any delicate structure which can easily get caught or break. The proposed design of the safety device, in addition, requires only a small amount of space, in particular only a low overall height.
The lighter according to the invention is preferably a stick lighter, i.e. the housing is preferably of elongate form or has at least one elongate front (distal) region, the actuating element being located in a region which is remote from the distal end of the housing.
The actuating element is preferably designed as a slide which is arranged on the top side of the housing. The slide is preferably designed such that it can be actuated by a thumb. The actuating element is preferably actuated by displacement in the direction of the distal end of the housing. In other words, the actuating element is preferably closer to the distal end of the housing in the actuating position than in the starting position.
The release device preferably comprises a button which is arranged on the bottom side of the housing. This button can be pushed into the activated position, from the rest position, in the direction of the top side of the housing. The button preferably comprises an activating portion which, at least in the activated position, is in contact with the safety lever. It is then preferably possible for the safety lever, in the activated position of the button, to be moved slidingly on the activating portion. The button is preferably designed and arranged such that it can be actuated by a finger, while the slide is actuated by the thumb.
The safety lever preferably has an elongate region which, starting from the pivot axis, extends in the direction of the distal end of the housing. Movement of the elongate region in the direction of the distal end is blocked by the locking element when the safety lever is located in the locking position. In other words, in this position, the locking element is located between the elongate region of the safety lever and the distal end and, if an attempt is made to displace the actuating element, the elongate region, with its end, pushes against the locking element. It is thus possible to dispense with the formation of hooks or other features on the safety lever, and the safety lever can easily be produced throughout, from the pivot axis to its front end, with an approximately uniform material thickness and thus with a high level of breaking strength.
The biasing (preloading) means preferably comprise a spring, in particular a helical spring or a (bent-over) leaf spring, with a first and a second free end. The first free end then pushes against the actuating element and the second end pushes against the safety lever, such that the spring pushes a region of the safety lever away from the actuating element. If the safety lever is articulated on the actuating element by way of a pin, the spring is preferably passed around the pin. In particular in the case of a helical spring, the helix axis is preferably concentric with the pivot axis.
A particularly simple construction of the safety device is achieved if the lighter has a frame which is arranged in the housing and in which the release device (that is to say preferably the button) is guided upwards, that is to say in the direction of the top side of the housing. An upwardly projecting protrusion on the frame then preferably forms the locking element. The actuating element is then preferably also guided on the frame. The actuating and safety devices can thus easily be realized on a single frame. The frame preferably has a region of essentially U-shaped cross section.
The lighter advantageously has further elements which are usually present in a stick lighter, in particular at least one of the following elements:

- a fuel tank, in particular for a liquid gas, arranged in the vicinity of the proximal end of the housing,
- a fuel nozzle arranged at the distal end of the housing,
- a fuel line which is arranged in the housing and is intended for supplying fuel from the fuel tank to the nozzle,
- a valve device in order to interrupt or release the supply of fuel to the nozzle, and
- an igniting device, preferably a piezoelectric igniting device, for igniting fuel at the distal end of the housing.

Both the valve device and the igniting device can preferably be actuated by displacement of the actuating element from the starting position into the actuating position.
In order to increase child safety further, the lighter preferably has resistance means which, upon displacement of the actuating element from the starting position into the actuating position, generate a force which is at least 30 Newton, preferably at least 40 Newton, particularly preferably at least 45 Newton. For this purpose, it is possible to provide a helical spring which extends in the longitudinal direction of the housing, is fitted to act between the actuating element and the housing and thus generates an additional resistance force. It is also possible, however, for the force to be generated solely by the igniting device (in particular piezoelectric igniter).

BRIEF DESCRIPTION OF THE DRAWINGS

An advantageous embodiment of the invention will be described in more detail hereinbelow with reference to the drawings, in which:

FIG. 1 shows a schematic side view, partly in longitudinal section, of a detail of an actuating mechanism with a safety device in the starting position;

FIG. 2 shows a schematic lateral X-ray view of the actuating mechanism of FIG. 1;

FIG. 3 shows a schematic side view, partly in longitudinal section, of the actuating mechanism of FIG. 1 in the actuating position;

FIG. 4 shows a schematic X-ray view of part of the actuating mechanism of FIG. 1, as seen from the rear;

FIG. 5 shows a schematic plan view of a stick lighter;

FIG. 6 shows a schematic side view of a stick lighter; and

FIG. 7 shows a schematic lateral X-ray view of selected parts of a stick lighter.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIGS. 1 to 4 show one embodiment of an actuating device which interacts according to the invention with a safety device. Located to the right of the detail in FIGS. 1 to 3 is a gas tank (not illustrated in FIGS. 1 to 3) with a valve, and to the left of this detail are a gas outlet (not illustrated either), in the form of a nozzle, and a piezoelectric igniter. The actuating mechanism serves for actuating the piezoelectric igniter and for releasing the valve on the gas tank. This is explained in more detail below in conjunction with FIG. 7. FIGS. 1 and 2 illustrate the mechanism in its starting position, in which it closes the valve, and FIG. 3 illustrates the mechanism in the actuating position, in which it releases the valve.
An actuating slide 2 is guided on the top side of a frame 1. The actuating slide 2 is guided, by way of a guide component 22, on a side wall 10 of the frame 1 and can be displaced to the left (in the actuating direction 92) from the starting position into the actuating position. This displacement takes place counter to the force of a helical spring 26, of which one end is connected to the slide 2 and the other end is connected to the frame 1. In order to prevent accidental actuation, a safety lever 4 is articulated, via a pin 43, on the actuating slide 2, beneath the guide component 22, on downwardly extending protrusions and can be pivoted about the pin 43. The safety lever 4 has a front portion 41 which extends obliquely downwards to the left. In the starting position, the end of this portion 41 is located opposite a nose 15 on the frame 1. The nose 15 thus blocks displacement of the safety lever 4 to the left and therefore prevents the actuating slide 2 from being displaced into the actuating position.
In order nevertheless to allow displacement of the actuating slide 2, a safety button 3 is fitted on the bottom side of the frame 1. This safety button has a pressure-exerting surface 31, a main portion 32 and a cylindrical activating portion 33 which extends upwards, in the direction of the safety lever, and is bevelled in a rearward direction at the top end. By virtue of the pressure-exerting surface 31 of the safety button 3 being pushed in the upward direction, this button is pushed into a recess on the frame 1. The activating portion 33 thus pushes the front portion 41 of the safety lever 4 upwards beyond the height of the nose 15 (this is the unlocking direction 91). In this position, the actuating slide 2 can then be displaced to the left (in the actuating direction 91) into the actuating position, as is illustrated in FIG. 3.
As soon as the actuating slide 2 has reached the actuating position, it is possible to let go of the safety button 3 since, in this position, the front portion 41 of the lever 4 is guided on the nose 15.
In order to ensure that the safety lever 4 reliably prevents actuation of the slide 2 as long as the button 3 is not pushed, a helical spring 44 is passed around the pin 43, the free ends of this spring pushing the slide 2 and the front portion 41 of the lever 4 apart from one another. This is illustrated in FIG. 2. FIG. 2 represents a so-called X-ray view, i.e. a view in which the boundary lines of all the relevant components are illustrated irrespective of whether they are visible in an actual model. Clearly visible is the spring 44, which is otherwise located, without being visible, between the slide 2 and lever 4. The front portion 41 of the lever 4 is thus pushed downwards by the spring force.
The safety lever 4 also has a rear portion 42, which is of angled design and, starting from the pin 43, extends first of all to the right (counter to the actuating direction 92) and then upwards (in a direction towards the slide 2). This rear portion 42 serves as a boundary for the pivoting region of the lever 4. If the front portion 41 moves downwards, away from the slide 2, then the rear portion 42 moves in the direction of the slide. When reaching a predetermined pivoting angle, the rear portion 42 abuts against the slide 2 (or, in an alternative configuration, against the frame 1) and thus prevents the lever 4 from pivoting further. As a result of its shape and its position of articulation, the lever 4 can thus be pivoted only over a predetermined, well-defined and relatively small angle range. In this way, on the one hand, straightforward assembly of the mechanism is ensured and, on the other hand, the lever 4 is prevented from getting caught on the bottom region of the frame 1, which would render the entire mechanism unusable.
The frame 1 comprises a horizontal base 12 and two vertical side walls 10 in a U-shaped arrangement. The base 12 contains a recess, in which the button 3 is guided vertically. This recess is formed by a front vertical crosspiece 13, a front horizontal crosspiece 14, a rear horizontal crosspiece 17 and a rear vertical crosspiece 16. The recess contains, in addition, an opening which is open in the upward direction and through which the activating portion 33 of the button 3 is guided.
FIG. 4 shows a view of part of the mechanism, as seen from the rear. Only half of the frame 1, the right-hand half, is illustrated here. However, the frame 1 is continued symmetrically on the left-hand side. Once again, an X-ray view has been selected in order to show the spring 44. This view shows a horizontal flange 11 on the frame 1, which serves for fixing the frame in the housing (not illustrated). In order to improve clarity, the spring 26 has been omitted from FIG. 4.
FIGS. 5 and 6 illustrate a stick lighter as a whole. The stick lighter comprises an elongate housing 5, which is divided up into a main body 51 and a front part 52 which extends out of the main body. The main body 51 has a flattened, essentially elliptical cross section. The snout-like front part 52 has a similar cross-sectional shape, albeit with smaller lateral dimensions. A part of the actuating slide 2 passed to the outside, namely a thumb rest 21, is arranged in a displaceable manner on the top side 54 of the main body 51. This thumb rest is connected to the guide component 22 through a slot-like opening (not visible) in the top side 54 of the main body 51. On the bottom side 55 of the main body 51, the pressure-exerting surface 31 of the safety button 3 is guided outwards through a round opening. Located at the front (distal) end 58 of the housing 5, in the region of slot-like openings 59, are a piezoelectric igniter (not visible) and a gas-outlet nozzle. A regulating wheel 53 for regulating the gas supply is located at the rear (proximal) end 57 of the housing 5. In the region of the transition from the main body 51 to the front part 52, the main body is tapered slightly in order for it to be possible for a protective sleeve to be pushed on.
FIG. 7 shows an X-ray view of a selection of the elements arranged in the housing 5, in order to illustrate how they interact. The actuating slide 2 and the safety lever 4, which is articulated thereon, are illustrated in the centre. Located in the direction of the proximal end are a gas tank 7 with a tank housing 71, and a closure valve 72 which is arranged at the front (distal) end of the gas tank. The closure valve has a valve head 73 which is prestressed in the direction of the proximal end by a spring and on which an angled valve lever 74 is fitted. The latter is supported on an edge of the valve such that movement of the free end of the valve lever 74 downwards, in the direction of the underside of the housing, results in the valve head 73 being pulled forwards, in the direction of the distal end of the housing. The valve is opened as a result. The flow of liquid gas which escapes through the valve can be adjusted by the regulating wheel 53 which can be seen in FIGS. 5 and 6.
A piezoelectric igniter 6 with a front end 61 and a pressure-exerting element 62 is located in the region of the distal end. Pushing in the pressure-exerting element 62 in the direction of the front end 61 makes it possible to generate an ignition spark at the front end 61. For this purpose, it is necessary to overcome an ignition force which, in the case of conventional piezoelectric igniters, is usually in the region of approximately 5-25 Newton. A gas line (not illustrated) is led from the valve 72 to the front end 61 of the piezoelectric igniter 6 and terminates there in a nozzle (not illustrated either).
A front extension component 24 which extends in the direction of the distal end of the housing, is fitted on the actuating slide 2. The extension component 24 has a nose 25 which butts against the pressure-exerting element 62 of the piezoelectric igniter 6. A protuberance 23 for actuating the valve 72 is located at the rear end of the actuating slide 2. This protuberance butts against the valve lever 74.
In order to actuate the stick lighter, as has been described above in conjunction with FIGS. 1 to 4, first of all the safety button 3 is pushed in. The actuating slide 2 is released as a result. Displacement of the actuating slide 2 in the actuating direction (in the direction of the distal end) then causes two things to happen. On the one hand, the protuberance 23 pushes the free end of the lever 74 in the direction of the underside of the housing, as a result of which the valve 72 is opened and gas flows through the gas line to the distal end, where it passes out of the nozzle. On the other hand, the nose 25 pushes the pressure-exerting element 62, counter to the ignition force, in the direction of the front end of the piezoelectric igniter. This results in an ignition spark, by means of which the gas flowing out through the nozzle is ignited to form a flame. The flame will continue burning until the user lets go of the actuating slide 2 again. The actuating slide 2 then returns automatically into the starting position.
The force which is necessary in order to actuate the slide 2 is preferably selected to be such that children under 36 months cannot usually apply this force. In particular, the actuating force is preferably greater than 30, or better greater than 40, Newton. This force can be adjusted by an appropriate selection of the spring 26 and piezoelectric igniter 6. If a suitable piezoelectric igniter is used, it is also possible to dispense with the spring 26. In this case, the piezoelectric igniter 6 should also generate, following actuation, a restoring force which is sufficient for the slide 2 to return automatically into its starting position.
At least the front part 52 of the housing preferably consists of metal, e.g. stainless steel, brass or aluminium, in order to ensure sufficient heat resistance. It is also possible, however, to use a thermostable plastic.
While the invention has been described with reference to a preferred exemplary embodiment, it is not restricted to this embodiment, and numerous variations are possible.
For example, the mechanism proposed can be used not just for stick lighters in which a slide is actuated in the direction of the distal end, but also for such lighters in which an actuating element is actuated in the direction of the proximal end, e.g. in the manner of the trigger of a gun. In this case, the mechanism can be installed in reverse direction.
In the embodiment explained above, the front portion 41 acts as the “operative” portion of the safety lever 4, i.e. this portion performs the locking function in relation to an immovable locking element. However, it is also possible instead, or in addition, for the rear portion 42 to be the “operative” portion and, for this purpose, to engage, e.g. by way of its end, in a recess on the frame or housing or behind a downwardly projecting protrusion on the frame or housing.
While the form of safety lever 4 proposed above results in a particularly straightforward design and high level of stability of the mechanism as a whole, the lever 4 may also be designed in a variety of other ways. It is thus possible for the operative portion of the lever (in the above embodiment the front portion 41) to extend for example, rather than in the direction of the distal end, in the direction of the proximal end. Instead of being pushed, the lever then operates by being pulled. In this case, the lever 4 may have provided on it, for example, a protrusion which interacts in the manner of a hook with a protrusion in the manner of the nose 15, which cannot be moved relative to the housing. In order to prestress the safety lever 4, it is also possible to use a type of spring other than a helical spring, e.g. a bent-over leaf spring. This need not necessarily be guided around the pin 43. Instead of use being made of a pin-type hinge, the lever 4 may also be fitted in a pivotable manner on the slide 2 by means of a film hinge or in some other known manner. It is also possible for the lever 4 to be formed integrally with the slide 2, in which case a flexible, preferably elastic, region is located between the slide 2 and the lever 4. If this region is elastic, it is possible to dispense with an additional spring, and the prestressing means are formed by the elastic region itself.
Instead of a button 3, the release device may also comprise a lever or some other type of device which ensures that the safety lever 4 can be pushed into the release position.
The slide 2 and the button 3 need not necessarily be guided on a frame. Instead, other fastening and guide means may be provided in the housing.
Of course, a different shape of housing to that illustrated above may be selected. Numerous variations are possible here, in particular for a housing shape which is cylindrical throughout, or for a housing with a rectangular or square cross section, etc.


List of designations

1	Frame
10	Side wall
11	Lateral flange
12	Frame base
13	Front vertical crosspiece
14	Front horizontal crosspiece
15	Nose
16	Rear vertical crosspiece
17	Rear horizontal crosspiece
18	Accommodating depression
2	Actuating slide
21	Thumb rest
22	Guide component
23	valve-actuating protuberance
24	Front extension component
25	Nose
26	Spring
3	Safety button
31	Pressure-exerting surface
32	Main portion
33	Activating portion
34	Finger rest
4	Safety lever
41	Front portion
42	Rear portion
43	Pin
44	Helical spring
5	Housing
51	Main body
52	Front part
53	Regulating wheel
54	Top side
55	Underside/Bottom side
56	Side wall
57	Proximal end
58	Distal end
59	Opening
6	Piezoelectric igniter
61	Front end
62	Pressure-exerting element
7	Gas tank
71	Tank housing
72	Valve
73	Valve head
74	Actuating lever
91	Unlocking direction
92	Actuating direction

Claims

1. A lighter comprising

a housing (5) with a proximal end (57) and a distal end (58),

a fuel tank;

a fuel nozzle;

an actuating device comprising an actuating element (2) which is displaceable relative to the housing, counter to an actuating force, between a starting position and an actuating position, wherein the actuating device, in the starting position, prevents fuel from being supplied from the fuel tank to the fuel nozzle and, in the actuating position, releases the supply of fuel,

a safety device (4) for preventing accidental displacement of the actuating element (2),

the safety device comprising a safety lever (4) which is connected to the actuating element (2) and which is pivotable relative to the actuating element (2) between a locking position and a release position, wherein the safety lever (4), in the locking position, is in engagement with a locking element (15) which is stationary relative to the housing (5), and wherein the lighter comprises means (44) for pushing the safety lever (4), counter to a biasing force, into the locking position, and

a release device (3) which is movable between a rest position and an activated position, wherein the release device (3), in the activated position, pushes the safety lever (4), counter to the biasing force of the biasing element (44), into the release position.

2. The lighter according to claim 1, wherein the actuating element (2) is designed as a slide which is arranged on a top side (54) of the housing (5), and in that the actuating element (2) is closer to the distal end (58) of the housing (5) in the actuating position than in the starting position.

3. The lighter according to claim 1, wherein the release device (3) comprises a button which is arranged on an underside (55) of the housing (5) and can be pushed into the activated position, from the rest position, in the direction of the top side (54) of the housing (5), the button comprising an activating portion (33) which is in contact with the safety lever (4), and the safety lever (4), in the activated position of the button, being slidingly movable on the activating portion (33).

4. The lighter according to claim 1, wherein the safety lever (4) has an elongate region (41) which extends essentially in the direction of the distal end (58) of the housing (5), and wherein movement of the elongate region (41) in the direction of the distal end (58) is blocked by the locking element (15) when the safety lever (4) is located in the locking position.

5. The lighter according to claim 1, the lighter comprising a spring with a first and a second free end, the first free end pushing against the actuating element (2) and the second end pushing against the safety lever (4), such that the spring pushes a region of the safety lever (4) away from the actuating element (2).

6. The lighter according to claim 1, the lighter having a frame (1) which is arranged in the housing (5) and in which the release device (3) is guided, a protrusion on the frame (1) forming the locking element (15).

7. The lighter according to claim 6, wherein the actuating element (2) is guided on the frame (1).

8. The lighter according to claim 1, the lighter comprising:

a fuel tank (7) arranged in the vicinity of the proximal end (57) of the housing (5),

a fuel nozzle arranged at the distal end (58) of the housing (5),

a fuel line arranged in the housing (5) for supplying fuel from the fuel tank (7) to the nozzle,

a valve device (72) for interrupting or releasing the supply of fuel to the nozzle, and

an igniting device (6) for igniting fuel at the distal end (58) of the housing (5),

it being possible for both the valve device (72) and the igniting device (6) to be actuated by displacement of the actuating element (2) from the starting position into the actuating position.

9. The lighter according to claim 1, the lighter comprising resistance means (6, 26) which, upon displacement of the actuating element (2) from the starting position into the actuating position, generate a force which exceeds 30 Newton.

10. The lighter according to claim 9, wherein the resistance means comprise a helical spring (26) which is arranged in the housing, extends in the longitudinal direction of the housing and is fitted to act between the actuating element and the housing