GB2398623A - Safety mechanism for a lighter - Google Patents

Abstract

A lighter 1 comprises a fuel container 2, a wick 3, a valve arrangement 4 comprising a valve 5 and an annular flange 6, a spring 10 biasing a flint 9 into contact with a sparking wheel 10, and a lever 14 pivoting on axles 16 in a groove 20 and is moveable between a valve operating and non-operating position. Groove 20 comprises a distorted Y-shape with a first end 21, second end 22 and a third end 23. Lever 14 has a thumb end 17, webs 27 either side of a formation 30 and an operating end 15 comprising a portion 28 which is larger than the flange 6 and a portion 29 which is smaller than the flange6. When lever 14 is depressed it contacts structure 19 so that valve 5 is not operated and only when lever 14 is laterally pushed in so that the axles 16 move to the second end 22 and then depressed so that axles 16 move to the third end 23 does the portion 29 engage flange 6 and permit valve 5 to be lifted and fuel to flow. When the pressure is released, lever 14 returns to the valve non-operating position where axle 16 is located at the first end 21. Spring 10 maybe different types of coil spring (fig 10) or a bent flat strip (fig 11). The lighter may have a wind shield 21. Groove 20 maybe of different shapes (figs 8, 9).

Description

HAND HELD LIGHTER

The present invention relates to a hand held lighter with safety features to prevent it being ignited accidentally or by children.

The present invention is particularly concerned with a hand held lighter of the type comprising a fuel container, a fuel valve for allowing fuel to be fed from the fuel container to an ignition point, a lever for opening the fuel valve, a flint and a rotatably mounted sparking wheel contacting the flint, so that when the sparking wheel is rotated, sparks are generated by the flint and projected to the ignition point. In operation, a user rotates the sparking wheel with the thumb while simultaneously depressing the lever to allow fuel to be fed to ignition point where it is ignited by the sparks. This type of hand held lighter is very well known in the art.

Lighters with safety features are also well known in the art. Various mechanisms are used. One mechanism is to lock the sparking wheel so that it cannot be operated until it has been unlocked. For example, US4822276 in the name of Bisbee discloses a childproof cigarette lighter in which a locking button is provided which must be depressed before the sparking wheel can be rotated. However, such constructions can be complicated and increase the cost of manufacturing the hand held lighter. It is desired to provide a design of hand held lighter which is unlikely to be operated accidentally or by children but which is simple to design and does not use a large number of parts.

The present inventor has realised that the lever which operates the fuel valve can be configured so that it is movable between a first position in which it will operate the valve and a second position in which it cannot operate the valve. This provides a particularly simple way of providing safety.

Accordingly, the present invention provides a hand held lighter comprising: a fuel container, a fuel valve for allowing fuel to be fed from the fuel container to an ignition point, a lever for operating the fuel valve, a flint, a rotatably mounted sparking wheel contacting the flint so that when the sparking wheel is rotated, sparks are generated by the flint and projected to the ignition point, the lever being movable between a valve operating position in which the lever can operate the fuel valve and a non-operating position, in which the lever cannot operate the fuel valve.

Suitably, the lever is slidable between the operating and non-operating position.

Normally, a lever for use in a hand held lighter comprises a pivoting lever with a thumb contacting portion and a valve-operating portion, with a fulcrum between them. The fulcrum may be formed by a pivot or axle projecting from the lever or projecting from a structure in which the lever is mounted. In the present invention the fulcrum, pivot or axle may be configured so that it is slidably movable between two positions so that the lever can be moved between the operating and non-operating positions. Suitably, the fulcrum comprises at least one projecting axle, which may project from the lever or from the structure in which the lever is mounted, the axle being slidably mounted in a linearly extending groove. The groove is preferably formed in which ever of the lever or structure does not have the axle. Preferably, there is a combination of an axial and a groove on each side of the lever, so that it is symmetrically supported and easy to operate.

Suitably, when the lever is in the operating configuration, it is movable, preferably by oscillation, between a valve-closed position and a valveopen position.

Means may be provided whereby the lever is biased into, or latched in the non-operating position. For example, resilient means may be provided biasing the lever away from the operating position. For example, biasing means such as a spring may be provided may acting on a part of the lever. It is particularly preferred that the biasing means is configured so that, when the lever is in the operating position, the lever is biased into the valve-closed position away from the valve-open position.

A single biasing means is preferably provided for biasing the lever away from the operating position and, when in the operating position, away from the valve-open position.

This can be achieved by arranging that the direction of action of the biasing means is the vector sum of the directions away from the valve operating position and away from the valve-open position.

The lever may be configured so that, in order to keep the lever in the valve operating position, the user has to maintain a force on the lever towards the valve operating position. However, the lever may be capable of being latched in the valve operating position. This can be achieved if, for example, the fulcrum comprises an axle moving in a groove, with biasing means being provided so that the axle will be pushed to one or other end of the groove, a selected point between the ends of the groove defining a position of unstable equilibrium. By pushing the lever from the non-operating position, against the force of biasing means, the axle may be moved past the point of unstable equilibrium so that it is subsequently pushed by the biasing means to the opposite end of the groove where it is latched in the operating position.

It is particularly preferred that means are provided so that after striking the sparks and releasing the lever, the lever will be returned to the non operating position rather than the operating position. In a particularly preferred embodiment, there is a third position in the groove, to which the axle will be biased by the force a user thumb when the user depresses the lever to operate the fuel valve. The third position in the groove is preferably configured so that the axle will move from third position to the first position (non operating) position under the influence of the biasing means when the user releases pressure from the lever. The third position in the groove is suitably placed at or near the position of unstable equilibrium.

The groove is preferably configured as a first groove segment connecting the first and third positions and a second groove segment, at an angle to the first groove segment and intersecting the first groove segment. In this way, the groove will have the shape of a distorted letter Y. The biasing means may comprise any suitable resilient means, for example a coil I:] :' spring. A coil spring can be used to provide a resilient force in its compression direction or at right angles to its compression direction, in a shear direction. Either force can be used. Alternatively, a flat coil spring can be used comprising a first arm and second arm which is resiliently movable with respect to the first arm, the first and second arm being joined by a flat coil section. The arms can be compressibly moved together or moved apart from one another in the plane containing the flat coil spring.

Further, a bent spring can be used, formed of a sufficiently resilient material.

According to the present invention, the lever has an operating position and a non operating position. In the operating position, a mechanical connection exists between the lever and the valve whereby operation of the lever operates the valve. In the non operating position, this mechanical connection is broken or disconnected so that] operation of the lever will not operate the valve. The mechanical connection may comprise any suitable design. Suitably, the lever comprises a valve operating surface.

The valve operating surface is suitably located on the opposite side of the fulcrum to a part of lever for operation by the user. The valve operating surface may comprise one I or more surfaces which, in the operating position, contact, during at least part of the motion of the lever when depressed by the user, an operating surface of the valve. For example, an annular valve may be provided having an annular projection over or under which the valve operating surface of the lever engages in the operating position. In the non-operating position, the valve operating surface is displaced from the operating surface of the valve in such a way that these surfaces do not contact one another during any substantial part of the operation of the lever by the user, so that the valve cannot be operated.

In a preferred embodiment, the lever comprises a slot having a narrow dimensioned portion and a large dimensioned portion, the valve comprising an operating surface which is of dimension greater than the dimension of the low dimension part of the slot but less than the large dimension part of the slot. The operating position of the lever corresponds to the low dimension part of the slot being placed adjacent to the operating surface of the valve. The non-operating part of the lever corresponds to the large dimension part of the slot being adjacent to the operating surface of the valve, but not contacting it, as it is too large a dimension.

The lever can be moved between the operating and non-operating position along the axis. Suitably, this axis extends generally at right angles to the axis of the valve.

Each of the fuel container, fuel valve, flint and sparking wheel may be of conventional design that need not be described here further. The lighter may comprise other conventional features, such as a shield surrounding the ignition point to prevent the flame being blown out by a draught. The sparking wheel may comprise side wheels, driving wheels or any other suitable modifications to provide further child safety features.

The lighter and its components, may be made of any suitable material, as is known in the art.

The present invention will be further described by way of example only with reference to the accompanying drawings, in which:

BRIEF DESCRIPTIONS OF TH E DRAWINGS

Figure l is schematic cross sectional view through a first embodiment of hand held lighter according to the present invention, with the lever in the non-operating position.

Figure 2 is a plan view, partially in cross section, of the hand held lighter of Figure 1.

Figure 3 is a schematic cross sectional view through the hand held lighter of figure 1, with the lever in the non-operating position and the lever depressed.

Figure 4 is a schematic cross section through the hand held lighter of figure 1, with the lever in the operating position.

Figure 5 is a schematic cross section through the hand held lighter of figure 1 with the lever in the operating position, depressed to actuate the valve.

Figures 6 and 7 show alternative embodiments of lever for use in the hand held lighter of figure 1.

Figures 8 and 9 show further alternative embodiments of bracket for use in the hand held lighter of figure 1.

Figure 10 shows a further embodiment of hand held lighter according to the invention.

Figure 11 show yet a further embodiment of hand held lighter according to the present invention.

DETAILED DESCRIPTION OF THE DRAWINGS

The hand held lighter of figure 1, generally designated 1, comprises a fuel container 2 of standard design containing fuel. Further, there is a wick 3 for fuel. The wick 3 is connected to a valve arrangement 4 of conventional design. The valve arrangement 4 further comprises a valve 5 of standard design. The valve 5 is slidable against the force of a spring inside the valve arrangement 4. In a raised position, in which the spring is compressed, a passage is opened for the flow of the fuel from the container 2 via the wick 3, through the central bore of the valve 5. The valve itself is of generally circular cross section. It comprises a tip, defining the ignition point at which a flame will be generated. Below the tip there is annular flange 6 whose function will be described further below. The valve arrangement 4 is mounted in a valve plug 7 of standard construction. A switch 8 is provided for further controlling the amount of fuel fed to the ignition point and hence the height of the flame, in a manner which is known in the art.

A flint 9 for the production of sparks is provided. The flint is driven into contact with the sparking wheel lO by a compression spring 11, in a manner which is known in the art.

The sparking wheel 10 may be of any suitable design, and is not described in detail.

However, the sparking wheel suitably comprises a central sparking wheel 10 having a profiled surface suitable for the generation of sparks. A pair of side wheels 12 are provided on either side of the sparking wheel 10 and coaxially mounted therewith. The side wheels are rotatably mounted with respect to the sparking wheel 10. The side wheels 12 have inwardly directed annular surfaces and the sparking wheel 10 has outwardly directed annular surfaces facing the inwardly directed annular surfaces of the side wheels 12. The side wheels 12 may be moved in compression towards the sparking wheel 10 so that the respective annular surfaces come into contact for frictional drive therebetween. By rotation of the side wheels, with sufficient pressure, the sparking wheel 10 itself is driven so that sparks are projected towards the ignition point and a: flame can be generated. This can provide a further safety feature in that sufficient \ pressure must be applied to the side wheels 12 for frictional drive of the sparking wheel 10. This can be difficult to achieve accidentally and it can be difficult for children to | apply the necessary pressure. i A lever 14 is provided which has a valve-operating end 15, a fulcrum comprising a pair of outwardly directed axles 16 and a thumb end 17 for operation by the user's thumb. A cylindrical spring 18 is provided for biasing the lever upwards and to the right of figure 1. The cylindrical spring 18 is mounted in a mounting l 9 of conventional design. l According to the conventional design, the flint 9 is mounted substantially on the central plane of the hand held lighter, this being the plane in which figure l is viewed. The axle 16 and parts of the lever shown in broken line are not in fact located in the central plane but are shown in order to allow the design to be understood. In practice, the lever 14 comprises a pair of webs which extend on either side ofthe central structure in which i the flint 9 is mounted. A respective axle is mounted extending outwardly from each I web. Further shown in figure I is a groove 20 which is formed in a bracket which supports the flint, the sparking wheel and the lever. Again, the groove 20 is not in fact located in the central plane, but is shown in figure I for clarity. The groove 20 comprises a first end 21, a second end 22 and a third end 23, whose function will be described further below. Finally, a shield 24 is provided surrounding the ignition point, in a manner which is known in the art.

Figure 2 shows a part plan view. In the top half of figure 2, the side wheel 12 and half of sparking wheel 10 can be seen. An axle 25 of the side wheel 12 can be seen mounted in a formation in the bracket 26. In practice, as can be seen in figure 1, the structure of the sparking wheel 10, side wheel 12 and axle 25 are mounted above the lever 14 and the structure of the lever 14 can be seen in the bottom half of figure 2. It can be seen that it comprises the thumb end 17 and a web 27 which passes to one side of a formation 30, which is not shown in detail, which comprises the flint. At the operating end 15 of the lever, there is a wide diameter portion 28, which is of a diameter greater than the outside diameter of the flange 6 of the valve 5. It can be seen that there is no interaction between the wide diameter portion 28 of the lever and the flange 6 of the valve. Operation of the lever in this position has no effect on the valve 5.

Connected to the large diameter portion 28 is a narrow portion 29, which is of width smaller than the outside diameter of the flange 6. The flange 6 is located above the level of the smaller diameter portion 29, so that if the smaller diameter portion 29 is moved into a position (as explained below) in which it is located below the flange 6, it will be able to interact with the flange 6 and lift the valve 5 to release fuel.

Figure 3 is schematic cross section through the hand held lighter of figure lwith the lever 14 depressed. It can be seen the lower part of the lever has come to rest on the top l of structure 19 so that there is very little movement of the lever. Further, as noted above, the lever is in a position in which the large diameter portion 28 is adjacent to the: flange 6. Raising the operating end of the lever 15 accordingly does not move the valve 5. No fuel is released and no flame is generated.

Figure 4 shows how the lever 14 can be pushed towards the left hand side of the paper I shown in figure 4. As the result, the axle 16 is deflected to the left hand side in the groove 20, coming to rest in the second position 21. It should be noted that there is peak 31 between the first position 21 and the second position 22. The spring 18 will tend to push the lever and the axle 16 in the groove 20 towards the top of the page. By moving the lever 14 along the groove, it passes over the peak 31 and is then pushed by the force of the spring into the second position 22 so that it comes to rest there, ready for operation.

Figure 5 shows what happens when the lever 14 is depressed.

Firstly it should be noted that the bottom part of the lever 14 has now been moved sufficiently far to the left to clear the edge of the structure 19 so that the lever can be depressed by a greater extent. The narrow diameter portion of the end of the lever 29 is now in a position to engage with the under side of the flange 6. As the end 14 of the lever is depressed, it rotates about the axle 16 causing the operating end 15 to rise, pushing the flange 6 and the valve 5 upwards. The fuel is accordingly released. At the same time, the user will have used their thumb to rotate the sparking wheel via the side wheels 12, causing sparks to be projected towards the ignition point so that a flame is generated. There is a limit to the upward motion of the valve 5. When this has been reached, further compression of the lever 14 leads to the axle 16 being forced back down the groove 20 to a lowest point, represented by the third position 23. Figure 5 shows the position in which the lever axial 16 has reached the third position 23. Once the pressure is released, the lever will return to its initial position. The arrow marked S shows the direction of action of the spring 18 on the lever 14. It can be seen that the direction of action of the spring 18 is such as to push the axle 16 towards the first position 21 rather than the second position 22. Accordingly, when pressure is released, the lever returns to the nonoperating position as shown in figure 1.

Figure 6 shows a second embodiment of lever for use with the present invention. The configuration of the web 27, axle 16 and thumb portion 17 is the same as shown in figure 2. However, instead of having a large diameter portion, there is a large dimension portion 32 connected to a small dimension portion 33 by a linear transition portion 34. That is, instead of using curved surfaces, straight surfaces are used.

Figure 7 shows a third embodiment of lever 14 for use with the present invention.

Again the axle 16 and the webs 27 are the same. Further, there is a small diameter portion 29 in the same way as shown in figure 2. However, in figure 7, the large diameter portion 35 is closed it end so that it forms a nearly complete circle.

Figure 8 shows a second embodiment of bracket 36 which may be used instead of the bracket 26 shown in figure 2. The axle 16 of the lever can be seen in position in the groove 37. In this case, instead of being formed in the shape of a deformed, upside down Y. the groove comprises the first position 38 and the second position 39 connected by the ridge 40. However, in this case, the third position is not defined by a distinct notch. Instead, it is defined by an elbow of the groove, which is in a form of a tick.

Figure 9 shows a third embodiment bracket 42 for use instead of the bracket 26 shown in figure 2. This bracket comprises a groove 43 which is the shape of a distorted U. The axle 16 can be seen resting in the first position 43. From this position, the groove comprises a downward section, a flattened ridge section 44 followed by an upward section leading to the second position 45. The third position is not defined by a notch but by a flat bottomed surface of the flattened U 46.

Figure 10 shows a further embodiment of hand held lighter according to the invention.

In this embodiment, all the features are the same except for the biasing means. In this case, the cylindrical coil spring 18 has been replaced by a flattened coil spring having a pair of arms 47 and 48 with a coil section 49 between them.

An even simpler biasing means can be formed by a bent flat strip as shown in figure 11.

The bent flat strip comprises an elbow portion 50 and end portions 51 and 52.

The present invention has been described above purely by way of example, and modifications can be made within the sprit of the invention, which extends to equivalents of the features described. The invention also consists in any individual features described or implicit herein or shown or implicit in the drawings or any combination of any such features or any generalization of any such features or combination.

Claims (8)

1. CLAIMS: 1. A hand held lighter, comprising: a fuel container, a fuel

   valve for allowing fuel to be fed from the fuel container to an ignition point, a lever for operating the fuel valve, a flint, a rotatably mounted sparking wheel, contacting the flint, so that when the sparking wheel is rotated, sparks are generated by the flint and projected to the ignition point, the lever being movable between a valve operating position in which the lever can operate the valve and a non-operating position, in which the lever cannot operate the valve.
2. 2. A hand held lighter according to claim 1, comprising biasing means for biasing the lever away from the operating position.
3. 3. A hand held lighter according to claim 2, wherein the biasing means is also for biasing the lever away from the valve operating position.
4. 4. A hand held lighter according to claim 1, 2 or 3 wherein the lever is mounted in a structure via a fulcrum, the fulcrum comprising an axle which is slidably mounted in a linearly extending groove.
5. 5. A hand held lighter according to claim 4, wherein the fulcrum comprises an axle displaceably mounted in a groove, biasing means being provided so that the axle will be pushed to one or other end of the groove, a selected point between the ends of the grooves defining a position of unstable equilibrium.
6. 6. A hand held lighter according to claim 4 or 5, wherein the groove comprises a third position to which the axle will be biased by the force of a user's thumb when the user depresses the lever to operate the fuel valve.
7. 7. A hand held lighter according to claim 6, wherein the third position in the groove is configured so that the axle will move from the third position to the first position under the influence of the biasing means when the user releases pressure from the lever.
8. 8. A hand held lighter substantially as herein described with reference to the accompanying drawings.