Patent ID: 12203654

DETAILED DESCRIPTION

FIGS.1and2illustrate a utility lighter10according to the present disclosure. The utility lighter10comprises a pocket lighter12and a sub-unit assembly14. The pocket lighter12comprises a body17, a pusher20and a cover35. The pocket lighter12extends along a longitudinal axis X. The length L1of the pocket lighter12along the longitudinal axis X is comprised between 5 cm and 12 cm. More precisely, the length L1of the pocket lighter12is approximately 8 cm. The width L2of the pocket lighter12is measurable along a transversal axis Y, which is perpendicular to the longitudinal axis X. The width L2can be comprised between 1.5 cm and 3 cm. For example, the width L2can be approximately 2.5 cm.

As depicted inFIGS.3and4, the pocket lighter12further comprises a piezoelectric ignition device18. The pocket lighter12is also provided with a pusher20. The piezoelectric ignition device18is connected to the pusher20. The connection between the pusher20and the piezoelectric ignition device18is such that the pusher20and a portion of the piezoelectric ignition device18which is the closest to the pusher20are firmly attached together. Consequently, when a user pushes the pusher20inward the pocket lighter12, the piezoelectric ignition device18is compressed to produce an elevated potential difference between its two poles18− and18+. A first pole30is connected to a jet24and a second pole32is connected to an electrode spring22. The electrode spring22is connected at a first end to the pusher20. The second end of the electrode spring22is connected to the sub-unit assembly14. The jet24comprises an upper end26and a lower end28, regarding the longitudinal axis X. In addition, the jet24is movable along the longitudinal axis X. The piezoelectric ignition device18provides a potential difference between the first pole30, located at the level of the upper end26of the jet24and the second pole32, located at the second end of the electrode spring22, which is in contact with the sub-unit assembly14. The first pole30and the second pole32are electrically insulated from one another by an insulated member31. The pocket lighter12also comprises a reservoir16of gaseous fuel. A valve34is located between the reservoir16and the jet24. The reservoir16is in fluid communication with the valve34. The jet24is movable along the longitudinal axis X inside the valve34between an open position and a closed position to selectively release gaseous fuel. Besides, the pocket lighter12comprises a biased pivotal arm36. The biased pivotal arm36is located between the piezoelectric ignition device18and the jet24. In addition, the biased pivotal arm36is made of an electrically conductive material. Thus, the biased pivotal arm36conducts the electrical potential from the piezoelectric ignition device18to the first pole30. For example, the material of the biased pivotal arm36is made of an electrically conductive material. For example, the biased pivotal arm is made of metal or carbon filled resin. As the pusher20compresses the piezoelectric ignition device18, the pusher20also acts on the biased pivotal arm36which is operatively connected to the jet24in order to open the outlet of the valve34to selectively release gaseous fuel. An arm spring38is placed underneath the biased pivotal arm36. The arm spring38allows maintaining the jet24in the closed position. Moreover, the pocket lighter12comprises a cover35. The cover35is usually provided for limiting the access of the ignition of the pocket lighter. In the present embodiment, the cover35comprises several abutments37. The abutments37cooperates with parts of the sub-unit assembly14in order to snap-fit the sub-unit assembly14and the pocket lighter12together. In addition, a cylindrical seal40is placed above the jet24. The cylindrical seal40provides the gaseous seal between the upper end26of the jet24when lifted by the pivotal arm36and the lower portion of the sub-unit assembly14, the top of the jet24being in electrical contact with the lower end56of the helical spring46.

As depicted inFIG.5, the sub-unit assembly14comprises a rigid support44, a helical spring46and an extended wand42. The extended wand42extends along the longitudinal axis X. The length L3of the sub-unit assembly14along the longitudinal axis X and extending outside the pocket lighter12is comprised between 1.0 cm and 5 cm. More precisely, the length L3of the sub-unit assembly14is approximately 2.7 cm. When the sub-unit assembly14is mounted on the pocket lighter12, the extended wand has a free end42E. The free end42E extends away from the pocket lighter12.FIG.7shows the rigid support44without the other elements of the sub-unit assembly14. The rigid support44comprises a plastic material, and thus does not have electrically conductive properties.

As it can be seen inFIGS.3,4and5, the rigid support44is mounted inside the extended wand42. When the sub-unit assembly14is mounted on the pocket lighter12, the rigid support44has a free end44E, extending away from the pocket lighter12. The free end44E of the rigid support44is located on the same side of the free end42E of the extended wand42along the longitudinal axis X. An inner space66is kept free between the free end44E of the rigid support44and the free end42E of the extended wand42. As depicted inFIG.5, the inner space66is located inside the extended wand42, but outside the rigid support44.

A protrusion52is provided on the external surface of the rigid support44. This protrusion52cooperates with a recess50of the extended wand42. The cooperation of these two elements holds the rigid support44in position inside the extended wand42. The rigid support44is further provided with a first notch72and a second notch74. The first notch72and the second notch74allow to assemble the sub-unit assembly14to the pocket lighter12. Thus, the connection of the sub-unit assembly14to the pocket lighter12is possible by corresponding abutment37. The first notch72, the second notch74and the abutments37are snap-fitted together. When snap-fitted, this connection is not removable. The rigid support44comprises also a longitudinal inner opening64. The longitudinal inner opening64extends along the longitudinal axis X and allows the helical spring46to pass inside. Thus, the helical spring46traverses from side to side the rigid support44through the longitudinal inner opening64. The helical spring46is guided and maintained inside the extended wand42by the rigid support44.

A shown inFIG.8, the helical spring46has a length L4, taken along the longitudinal axis X, comprised between 5 mm and 120 mm. More preferably, the length L4of the helical spring46is of 32 mm. The outer diameter D46of the helical spring46is comprised between 0.5 mm and 2 mm. For example, the outer diameter D46is of 1 mm.

Actually, as shown inFIG.5, when the sub-unit assembly14is assembled on the pocket lighter12, the rigid support44protrudes outside the pocket lighter12and along the longitudinal axis X at a length L5. The length L5is thus measured between the free end44E of the rigid support44and a contact line13between the sub-unit assembly14and the cover35. The length L5can be comprised between 5 mm and 40 mm. For instance, the length L5is of 12.5 mm. In addition, still when the sub-unit assembly14is assembled on the pocket lighter12, the helical spring46protrudes to a length L6outside the pocket lighter12and along the longitudinal axis X. The length L6is thus measured between a free end46E of the helical spring46and the free end44E of the rigid support44. The length L6can be comprised between 2 mm and 10 mm. For instance, the length L6is of 4 mm. Therefore, we can understand that the free end46E of the helical spring46is located inside the extended wand42, but outside the free end44E of the rigid support44.

Besides, when assembled together, the helical spring46, the rigid support44and the extended wand42extend concentrically around the longitudinal axis X, outside the pocket lighter12. The arrangement being such that the helical spring46is the closest element from the longitudinal axis X, the extended wand42being the furthest element from the longitudinal axis X, and the rigid support44being located concentrically between the extended wand42and the helical spring46. Therefore, as depicted inFIG.5, the outer diameter D46of the helical spring46is smaller than the outer diameter D42of the extended wand42, and the outer diameter D44of the rigid support44is comprised between the outer diameter D42of the extended wand42and the outer diameter D46of the helical spring46. For example:the outer diameter D42of the extended wand42can have a dimension comprised between 5 mm and 11 mm,the outer diameter D44of the rigid support44can have a dimension comprised between 4 mm and 10 mm,the outer diameter D46of the helical spring46can have a dimension comprised between 0.5 mm and 2 mm.

Coming back toFIG.8, the helical spring46comprises three portions along its length: a first end portion58, a middle portion60and a second end portion62. The first end portion58is provided to cooperate with the jet24. The middle portion60is provided to be received in the longitudinal inner opening64of the rigid support44. The top portion62is provided to protrude in the inner space66of the length L6when the long helical spring46is assembled in the sub-unit assembly14. In such a configuration, the helical spring46has a free end46E which corresponds to the end of the top portion62. Thus, as shown for example inFIG.5, the free end46E of the helical spring46is located on the same side of the free ends42E and44E of the extended wand42and the rigid support44. In addition, the free end46E of the helical spring46is located inside the extended wand42, but outside the free end44E of the rigid support44.

The pitch of the three portions58,60,62of the helical spring46is comprised between 0.1 mm and 0.6 mm. The pitch of the middle portion60can be comprised between 0.1 mm and 0.2 mm. For example, the pitch of the middle portion60is 0.1 mm. The pitch of the first end portion58is comprised between 0.2 mm and 0.6 mm. The pitch of the second end portion62is comprised between 0.2 mm and 0.6 mm. Regarding the entire helical spring46, the pitch of the middle portion60is always smaller than the pitch of the first end portion58and the pitch of the second end portion62. Actually, the coils of the middle portion60are dead coils. In other words, the coils of the middle portion60are closer in sequence whereas coils of the first end portion58and the second end portion62are not. Such dimensioning has the following interesting features. In the area of the first end portion58, the pitch is dimensioned such that the first end portion58easily contacts the upper end26of the jet24. Indeed, the coils of the first end portion58are not close in sequence. The helical spring46can therefore be compressed in the first end portion58. Thus, the helical spring46contacts the upper end26of the jet24in being in compression, which guarantees a suitable contact between these two members. In the area of the second end portion62, the pitch is dimensioned in order to suitably diffuse the gas in the air and thus in order to create an easily flammable mixture of air and gas in the inner space66. In other words, the second end portion62of the helical spring46is the gas diffuser of the utility lighter. Consequently, the helical spring46fulfills the function of diffuser for the utility lighter10. In the area of the middle portion60, the coils of the helical spring46delimit an inner duct56. The inner duct56extends concentrically along the longitudinal axis X. The pitch of the helical spring46in the area of the middle portion60is so small that the gas cannot easily go through the coils. The gas is thus confined inside the helical spring46and thus inside the inner duct56. Therefore, the helical spring46fulfills a function of gas duct for the utility lighter10. In addition, the coils being closer in sequence in the middle portion60, they create a rigid portion which facilitates the insertion of the helical spring46in the rigid support44during the assembly.

Actually, according to one embodiment, the pitches of the first end portion58and the second end portion62are identical. Therefore, the helical spring is symmetrical with respect to a perpendicular axis S through its middle along its length L4. The pitch of the first end portion58is similar to the pitch of the second end portion62in order to insert the helical spring46in any longitudinal direction inside the longitudinal inner opening64during the assembly of the sub-unit assembly14. Any free end of the helical spring46can thus be inserted at first inside the longitudinal inner opening64. Consequently, this feature facilitates the assembly of the sub-unit assembly14by avoiding a step of differentiation between the first end portion58and the second end portion62. According to another embodiment, the pitches of the first end portion58and the second end portion62are not identical. However, in such a configuration, the pitch of the middle portion60is still smaller than the pitch of the first end portion58and the pitch of the second end portion62.

As better shown inFIG.6, the sub-unit assembly comprises the extended wand42. The extended wand42has a general cylinder shape, which extends along the longitudinal axis X. The extended wand42comprises an aperture54at its upper end. The upper end of the extended wand42corresponds to its free end42E when the sub-unit assembly14is assembled with the pocket lighter12to form the utility lighter10, as illustrated inFIGS.3and4. The flame escapes from this aperture54. The extended wand42further comprises at its lower end42L, opposite to the free end42E, an extension48. This extension48has a general shape of a tongue and has a free end48E. The length L7of the extension48along the longitudinal axis X is measured between the lower end42L of the extended wand42and the free end48E of the extension48. The length L7of the extension48can be comprised between 5 mm and 15 mm. For instance, the length L7is of 11.5 mm. During the actuating downwards of the pusher20, the extension48allows for contact of the extended wand42with the electrode spring22. The electrical potential created at the second pole32is therefore transmitted to the extended wand42through the extension48. In other words, the electrode spring22is connected to the sub-unit assembly14by means of the extension48. The extended wand42also comprises an antenna43. The antenna43protrudes forwards the inner space66. The antenna43has a general triangular shape when viewed from the face. The antenna43comprises a base45and a tip47. The distance D5between the tip47and the free end of the helical spring46is favorable for the apparition of the electrical arc, which results of the potential difference created by the piezoelectric ignition device18. For example, as illustrated inFIG.5, the distance D5between the tip47and the free end of the helical spring46is comprised between 2.5 mm and 3 mm. The electrical arc is thus created in an interelectrode space which is located in the inner space66. When the arc electric created between the tip end47of the antenna43and the free end of the helical spring46(i. e. the end of the top portion62) meets the mixture of gas and air, a flame is so created. As a result, the flame escape from the utility lighter10through the aperture54, located at the free end42E of the extended wand42.

The sub-unit assembly14thus assembled is rigid. Especially, the sub-unit assembly14is rigid enough to not bent and to keep a straight and elongated shape during the assembly between the sub-unit assembly14and the pocket lighter12. The feature is made possible partly thanks to the rigid support44and the extended wand42.

When the sub-unit assembly14and the pocket lighter are connected together, the ignition of a flame is as follow. A user pushes downwards the pusher20. The piezoelectric ignition device18is thus actuated and creates a first electric potential on the electrode spring22and a second electric potential on the biased pivotal arm36. The extension48contacting the electrode spring22, the first electric potential is then transmitted to the extension48. Because of the electrically conductive properties of the extended wand42, the first electric potential is conducted along the extended wand, and especially until the tip47of the antenna43. When the pusher20is pushed downwards, the biased pivotal arm36contacts the piezoelectric ignition device18. The second electric potential is thus transmitted to the biased pivotal arm36. Then, the second electric potential is transmitted to the jet24. The second electric potential is therefore transmitted to the helical spring46through the upper end26of the jet24. The helical spring46fulfills therefore a function of electrical conductor. The first electric potential and the second electric potential create therefore a potential difference which is favorable to the creation of an electrical arc in the interelectrode space. However, despite the electrical properties of the extended wand42, there is no risk of electric shock for a user, since the first pole30is surrounded by the body17of the pocket lighter12. The body17being made of a non-electrically conductive material, the user cannot therefore touch the first pole30. In the meantime, when the pusher20is pushed downwards, it actuates the biased pivotal arm36which raises the jet24. The jet24releases the valve34. As a result, the gas is released from the reservoir16and through the jet24and the helical spring46until the second end portion62of the helical spring46. The mixture of gas and air thus created in the inner space66then catches fire should it meets the electrical arc.

FIGS.9,10,11and12illustrate a second embodiment of a utility lighter10according to the present disclosure. In this second embodiment, the rigid support44and the cover35are formed in a sole molded piece33. This molded piece33, shown inFIG.12, is molded in an electrically insulating thermoplastic resin. The sub-unit assembly14, according to this second embodiment, thus comprises also the cover35. Such a molded piece33has the advantage of reducing the number of pieces required, since the cover35and the rigid support44are the same piece. In addition, there is no more need for abutments37and second notch74, since the rigid support44and the cover35are already assembled together. Furthermore, such an embodiment improves the insulation of the electrical circuit by avoiding short-circuit through the cover35. Indeed, the cover35, usually metallic, could create a failure in the ignition. When the cover is made of an electrically insulating thermoplastic resin, there is no more risk of any short-circuit. Besides, this feature protects the user of a possible electrical discharge in his fingers.

The molded piece33comprises two protrusions39, which allows it to be snap-fitted to the body17of the pocket lighter12. When snap-fitted, this connection between the molded piece33and the body17is not removable.FIG.9illustrates only one protrusion39, the other protrusion39being hidden by the cover.

This second embodiment provides another advantage that consists on a greater precision of positioning of this molded piece33with respect to the pocket lighter12and therefore to the jet24. Thus, the achievement of a good sealing between the upper part26of the jet24and the cylindrical seal40is facilitate.

The disclosure further concerns a method for manufacturing a flame producing assembly. The method consists first to provide the sub-unit assembly14. To this aim, the helical spring46is inserted inside the rigid support42. Then, this set is snap-fitted inside the extended wand42, forming therefore the sub-unit assembly14. After that, the sub-unit assembly14according to the first embodiment, is snap-fitted on the cover35of the pocket lighter12, the cover35being previously attached to the body17of the pocket lighter12. According to the second embodiment, the sub-unit assembly is snap-fitted directly on the body17of the pocket lighter12. In this way, according to either the first or the second embodiment, the sub-unit assembly14is fixedly attached to the pocket lighter12. Such an assembly has the advantage to be easily implemented. In addition, the assembly of the utility lighter10according to the second embodiment has the advantage to be easier assembled than the utility lighter10according to the first embodiment, the preliminary fixing step of the cover35on the body17not being required. An assembly on an automatic machine for producing several flames producing assembly is therefore achievable.