Abstract:
The present invention involves a lighter for preventing unintended use. In one aspect, a striker wheel including a rotation limiting means is provided, where an arc formed by the rotation limiting means is preferably greater than about 100° and less than or equal to about 220°. The rotation limiting means may comprise a single or multiple protrusions, a shield extending from one or more outer grip wheels, or a cover attached to a periphery of the striking wheel.

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention relates generally to a lighter, and more particularly, to a spark ignition lighter for preventing unintended lighting of a flame and a method for using same. 
     2. Description of Related Art 
     A typical gas lighter  1 , as shown in FIG. 1, comprises a housing  2  into which flammable material is held. A flint  3  is mounted in a depression  4  and is supported by a compression spring  5 . A gas nozzle  6  receives flammable material from within the housing  2 . A valve  9  is provided for controlling the release of the flammable material from the housing. The valve can be opened by downward pressure on a gas lever  7 , which pushes up an en  8  to lift a nozzle  6  to open the valve  9 . 
     The gas lever  7  is preferably operated in conjunction with a spark producing mechanism so that the flow of flammable material (fuel) is ignited soon after it commences. For example, lighters employing conventional spark wheels require a user to rotate a toothed spark wheel against a flint in order to generate a spark. The user then depresses the gas lever to release gas and produce a flame. To illustrate, a striker wheel  10  is provided which preferably includes a pair of side grip wheels  13  to rotate a central wheel  11  which has a roughened peripheral surface  12  for frictionally engaging with the flint  3  to cause sparks. 
     Although lighters of this type can produce a flame with a minimal amount of difficulty, such ease of operation can also result in a potentially hazardous situation due to unintentional operation, for example, if such a lighter is left unattended within reach of a child. 
     Accordingly, there is a need for a lighter which reduces the chances of unintentional operation in a simple and effective way, while at the same time maintaining its user-friendliness for intended users. 
     SUMMARY OF THE INVENTION 
     The present invention relates to a lighter resistant to unintentional operation, wherein the lighter employs a system and method which presents increased difficulty of operation by unintended users, and more particularly, relates to a spark ignition lighter with such a system. 
     In one aspect of the present invention, a lighter is provided comprising a gas reservoir; a gas nozzle; means to cause gas to be supplied from the reservoir to the gas nozzle; a flint; a striker wheel rotatable to frictionally engage the flint to generate sparks for igniting gas emitted at the gas nozzle, said striker wheel including a pair of attached outer grip wheels for rotation of the striker wheel by a user; and a rotation limiting means for limiting rotation of the striker wheel. 
     In another aspect of the present invention, a striker wheel unit is provided comprising a striker wheel rotatable to frictionally engage a flint to generate sparks for igniting gas emitted at a gas nozzle; and a rotation limiting means for limiting rotation of the striker wheel. 
     These, and other aspects, features and advantages of the present invention will be described or become apparent from the following detailed description of the preferred embodiments, which is to be read in connection with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exemplary illustration of a typical gas lighter comprising a housing into which flammable material is held. 
     FIG. 2 depicts an exemplary central striker wheel according to an aspect of the present invention. 
     FIG. 3 depicts an exemplary front view of the striker wheel of FIG. 2 showing a protruded area. 
     FIG. 4 depicts an exemplary striker wheel according to another embodiment of the present invention. 
     FIG. 5 depicts an exemplary striker wheel unit wherein at least one outer grip wheel includes a shield to limit the rotation of the striker wheel according to an embodiment of the present invention. 
     FIG. 6 depicts an exemplary striker wheel unit wherein both outer grip wheels include a shield to limit the rotation of the striker wheel according to an embodiment of the present invention. 
     FIG. 7 depicts an exemplary striker wheel unit wherein the striker wheel includes a cover connected to its peripheral surface to limit the rotation of the striker wheel according to an embodiment of the present invention. 
     FIGS. 8 and 9 depict an exemplary method of producing a flame using a lighter according to an aspect of the present invention. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     With reference now to the drawings, a new and improved lighter embodying the principles of the present invention will be described. 
     FIG. 2 depicts an exemplary central striker wheel  201  according to an aspect of the present invention. The striker wheel  201  includes a protruded area  203  which extends over a selected arc of the circumference of the striker wheel  201 . As a result, when the striker wheel  201  is rotated, an end surface  204  or  205  of the protruded area  203  will abut against the flint  3  or material surrounding the depression  4 , thus substantially preventing further rotation. 
     Generally, to successfully produce a flame from a spark ignition lighter, the striker wheel unit  10  must be rotated a minimum of about 120°. An arc of the periphery  207  which is blocked by the flint  3  of the depression  4  in which the spring  5  is positioned can comprise for example, about 20° to about 50°. To ensure that a second ignition cannot result from rotating the striker wheel, in a preferred embodiment the protruded area  203  preferably creates an arc in which the angle A to B is greater than about 100°. 
     Thus, a minimum allowed rotation of the striker wheel is, for example, about 140°, and a maximum allowed rotation is about 260°. In a preferred embodiment, the minimum rotation is between about 140° and about 170°, and a maximum rotation is between about 230° and less than about 260°. 
     FIG. 3 depicts an exemplary front view of the striker wheel of FIG. 2 showing the protruded area  203 . Outer grip wheels  301  are attached to either side of the striker wheel  201 . The engagement of the outer grip wheels  301  to the striker wheel may be, for example, by a central stub  303  being positioned in a suitable receiving depression or aperture located on an axis of the striker wheel  201 . The outer grip wheels  301  are also provided with outer stubs  305  for engagement with the body of the lighter. 
     FIG. 4 depicts an exemplary striker wheel according to another embodiment of the present invention. The striker wheel  400  includes at least two protrusions  401  and  403  which abut from and limit the rotation of the striker wheel  400 . An angle (A,B) formed by the protrusions is preferably greater than about 100°. 
     FIG. 5 depicts an exemplary striker wheel unit wherein at least one outer grip wheel includes a shield to limit the rotation of the striker wheel according to an embodiment of the present invention. At least one outer grip wheel  501  or  505  includes an attached shield  503  which extends over the striker wheel  500  when the striker wheel is engaged with both outer grip wheels  501  and  505 . The arc formed by the shield is preferably of a length as described in relation to FIGS. 2 and 4; i.e., formed by an angle greater than about 100°. 
     FIG. 6 depicts an exemplary striker wheel unit wherein both outer grip wheels include a shield to limit the rotation of the striker wheel according to an embodiment of the present invention. Each outer grip wheel  601  and  603  includes a shield  605 . Preferably, each shield  605  extends about halfway across the striker wheel  500  (although unequally sized shields can be provided) such that the striker wheel is at least partially covered. The arc formed by the shield is preferably of a length as described in relation to FIG. 5; i.e., formed by an angle greater than about 100°. 
     FIG. 7 depicts an exemplary striker wheel unit wherein the striker wheel includes a cover connected to its peripheral surface to limit the rotation of the striker wheel according to an embodiment of the present invention. The cover  700  is preferably of a width  703  that at least partially covers the width of the striker wheel  500 , such that an end portion  705  will abut against the flint  3  or the material surrounding depression  4  substantially preventing further rotation. Again, the arc formed by the cover  700  is preferably of a length as described in FIG. 5, i.e., formed by an angle greater than about 100°. 
     FIGS. 8 and 9 depict an exemplary method of producing a flame using a lighter according to an aspect of the present invention. In FIG. 8, initially, lever  800  is depressed to allow gas to escape from the nozzle  801 . At the same time, modified striker wheel unit  805  which has been modified according to an aspect of the present invention is rotated in the direction of arrow  803  until the protruded area  203 , the protrusions  401  and  403 , the shields  503  or  605 , or the cover  700  abuts the flint  3  or the surrounding area of the depression  4  into which the flint is placed. That is, the modified striker wheel is rotated until, for example, the end  205  (or its equivalent) strikes the flint  3  or the supporting structure thus preventing further rotation. 
     Once in this position, the modified striker unit is rotated in the direction of arrow  901  as depicted for example, in FIG. 9, thus allowing a flame  903  to be struck. Further rotation of the modified striker unit  805  (to strike a light again) is not possible until the modified striker unit is again rotated in the direction of arrow  803 . 
     Thus, advantageously, a lighter according to an aspect of the present invention requires a preliminary rotation of the striker wheel (which is in a direction such that any sparks generated will be directed away from the gas nozzle) before another striking of the striker unit which is of sufficient rotation to generate a flame can be undertaken. Such a set of steps is difficult, for example, for a child to perform and also prevents unintentional lighting of a flame, thus resulting in an improvement in the safety of the lighter. 
     Although illustrative embodiments of the present invention have been described herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various other changes and modifications may be affected therein by one skilled in the art without departing from the scope or spirit of the present invention.