CERTIFICATION OF TRANSLATION I, VOUGNY Christophe, of CABINET PLASSERAUD, 65/67 rue de la Victoire, 75440 PARIS CEDEX 09, FRANCE, do hereby declare that I am well acquainted with the French and English languages, and attest that the document attached is a true English language translation of the text of International Patent Application no. PCT/FRO3/01072. Dated this October 8, 2004 VOUGNY Christophe GAS LIGHTER The present invention relates to gas lighters. More particularly, the invention relates to a gas 5 lighter including a fuel reservoir made of an amorphous polymer material which includes a top wall through which a well passes, the well being provided with a gas dispensing device whicf includes a tubular element engaged in the well in leak tight manner. 10 The above-mentioned amorphous polymers are polymers having chains of monomers disposed in disordered manner, unlike semi-crystalline or crystalline polymers, in which the chains are disposed uniformly. Certain amorphous polymers offer advantages for making fuel reservoirs for 15 lighters, with particular examples worth mentioning being the categories of acrylonitrile butadiene styrenes (ABSs) or of styrene acrylonitriles (SANs). In fact, certain amorphous polymers are transparent, which makes it possible to see the level of liquid fuel remaining in the 20 reservoir, and they are generally less expensive and easier to use than semi-crystalline polymers. In general, amorphous polymers are relatively brittle at ambient temperature because their elongation at the elastic limit is small, and generally less than 25 5%. Such polymers thus cannot withstand extension stresses because such stresses cause micro-cracks and therefore gas leaks. In addition, their mechanical properties deteriorate as the material ages. Therefore, to fit the gas dispensing device in the 30 top wall of such reservoirs, complex fitting means are used, such as those disclosed in Document WO-A 01/18452. In that document, the tubular element is provided with an O-ring gasket that procures sealing between said tubular element and the well in the top wall of the 35 reservoir, and that tubular element is held in the well by means of a threaded ring that is screwed into a tapped upper portion of the well.
2 The device described in that document suffers from the drawback of comprising parts that are numerous and complex, which complicates assembly of the lighter, and thus increases its manufacturing cost and reduces its 5 reliability. In addition, the large overall size of such a dispensing device limits the possibilities of miniaturizing the lighter. Finally, that solution does not6-ffer satifs-fatory sealing insofar-as the O-ring gasket, which is compressed to a relatively small extent 10 only so as not to cause any micro-cracks, does not guarantee excellent sealing. An object of the present invention is to mitigate those drawbacks. To this end, a lighter of the type in question is 15 characterized in that the top wall of the reservoir is provided with an annular groove extending around the well, in that the tubular element of the dispensing device is engaged in the well, and in that said top wall is reinforced by a ring engaged in the annular groove, 20 the top wall forming an annular wall between the groove and the well, which wall is clamped between said ring and said tubular element, so as to obtain sealing between said tubular element and the well by mutual contact only. By means of these provisions, a lighter is obtained 25 whose reservoir is relatively inexpensive because amorphous polymer is used, but that nevertheless guarantees excellent sealing because of the presence of the reinforcing ring engaged in the annular groove that surrounds the well. This reinforcing ring not only 30 avoids the presence of extension stresses in the top wall of the reservoir and in particular in the annular wall situated between the groove and the well, but also generates compression stresses in the annular wall, thereby avoiding the appearance of micro-cracks. Thus, 35 the tubular element of the gas dispensing device is fitted in the well of the reservoir with excellent sealing.
3 In addition, the gas dispensing device is fitted particularly simply because it is not necessary to use a separate-gasket interposed between the.wall and the tubular element, nor to use a screw-fastenable ring to 5 hold said tubular element. In preferred embodiments of the invention, it is optionally possible, in addition, to use any of the following provisions: - the annular groove has a first annular face facing 10 radially outwards, and the ring has a first annular face facing radially inwards and engaged in tight-fitting manner against the first annular face of the groove; - the annular groove has a second annular face facing radially inwards, and the ring has a second 15 annular face facing radially outwards and engaged without being tight-fitting in said second annular face of the groove; - the well, the tubular element, the ring and the groove are in a circularly-symmetrical shape, the groove 20 having a certain inside diameter, and the ring having an inside diameter that is no larger than the inside diameter of the groove, the well having a certain diameter and the tubular element having a certain outside diameter that is no smaller than the diameter of the 25 well; - the groove has a certain outside diameter, and the ring has an outside diameter that is no larger than the outside diameter of the groove; - the lighter is provided with a head that overlies 30 the reservoir and that includes an ignition device and a control device controlling the gas dispensing device, said ring being part of the head of the lighter; - the head and the ring are formed as a single piece made of a semi-crystalline polymer material; 35 - the tubular element is engaged by force in a hole provided in the head; 4 - the gas dispensing device includes a regulating device and a valve that are received inside the tubular element; . - the tubular element is made of metal and has an 5 internal shoulder against which a micro-porous disk is held by a retaining ring, the tubular element having one end crimped against said retaining ring; --the reservoir has a side wall against which said top wall is bonded; and 10 - the reservoir is formed of a material chosen from ABS and from SAN. Other characteristics and advantages of the invention appear on reading the following description given by way of non-limiting example and with reference 15 to the accompanying drawings, in which: - Figure 1 is a vertical section view of an embodiment of a lighter of the invention; and - Figure 2 is a fragmentary enlarged view of the section view of Figure 1. 20 In the figures, the same references are used to designate identical or similar elements. Figure 1 shows a gas cigarette lighter 1 including a reservoir 2 serving to contain a fuel that is pressurized and partially liquid, and such as, for example, 25 isobutane. In the embodiment shown, the reservoir is formed of a bowl 3 that is U-shaped in section, and that has a bottom 4 and an annular side wall 5 that extends upwards from the bottom to a top end 6. 30 The top end is closed off by a top wall 7 which, in the example shown, is a separate part fixed, e.g. by bonding, to the side wall 5. The entire reservoir 2 is made of at least one amorphous polymer material, chosen, for example, from 35 acrylonitrile butadiene styrenes (ABSs) and from styrene acrylonitriles (SANs). By way of example, the bowl 3 may be made of SAN, and the top wall 7 may be made of ABS, it 5 being possible, in known manner, to bond those materials together, e.g. by ultrasonic sealing. The-adv-antageQf such amQrphous polymers is, in particular, that they are inexpensive, and easy to 5 implement. In addition, some of them may be transparent, which makes it possible for the user of the lighter to see the level of liquid fuel remaining in the reservoir. Naturally, other amorphous-type polymers may be used, provided that their mechanical and chemical 10 properties are compatible with them being used as a gas lighter reservoir. To accommodate the gas pressure prevailing inside the reservoir, the bowl 3 and the top wall 7 have walls that are relatively thick, and the bowl may optionally be 15 provided with a bridge 8 that extends vertically from the bottom 4 while interconnecting two opposite faces of the side wall 5. The top wall 7 of the bowl is provided with a well 9 which, in the example shown, extends vertically and which 20 may advantageously be in the shape of a cylinder that is circularly symmetrical. The well 9 receives a gas dispensing device 10 that is actuated by a control device 11 carried by a head 12 of the lighter that overlies the reservoir 2. 25 The head 12 also forms a support to which there can be fitted an ignition device 14 and a cover 13 forming a screen against air draughts. The ignition device is known per se, and, for example, it may comprise a serrated friction wheel 15 and 30 a flint 16, but naturally it is possible to use other types of ignition, such as piezoelectric devices, for example. In the embodiment shown, the head 12 is retained against the top wall 7 of the reservoir by catches 17 on 35 said head that co-operate by snap-fastening with complementary catches 18 integrally molded with the top wall 7 of the reservoir.
6 In the example considered herein, the dispensing device 10 includes a tubular element 19 which may advantageously be made of metal and be in the shape of a circularly symmetrical cylinder. 5 For example, the dispensing device 10 may also include: - a regulating device for regulating the gas flow rate, which device may, for example, comprise a microporous disk 20 which is held against an internal 10 shoulder 21 in the tubular element 19 that is formed in the vicinity of the bottom end of said tubular element, the microporous disk 20 masking an orifice 21a formed in the center of the shoulder 21 and being pressed against the bottom face of said shoulder by a rigid ring 22 which 15 is itself retained at the bottom portion of the tubular element by crimping the bottom end 23 of said tubular element; and - a valve 24 formed by a tubular hollow body 25 which, in its bottom portion, carries closure means such 20 as an elastomer disk 26 adapted to close off the above mentioned orifice 21a, which hollow body defines a gas outlet duct 27 which communicates with the inside of the tubular element 19 via slots 28 or the like provided in said hollow body. 25 The valve and the regulating device for regulating the gas flow rate are advantageously received inside the tubular element 19. The above-mentioned gas outlet duct 27 opens out in the vicinity of the ignition device 14. 30 The control device 11 comprises a fork 20 mounted to tilt about a pin secured to integral with the head 12. A first end 31 of the fork 20 co-operates with a setback 32 formed at the top portion of the hollow body 25 so as to raise said hollow body when the user presses on the 35 second end 33 of the fork. In order to keep the valve 24 closed off in the rest position, a compression spring 34 7 is disposed between the bottom face of the end 33 of the fork and the bottom 35 of a well formed in the head 12. Asshown in more detail in Figure 2, the tubular element 19 of the dispensing device 10 is engaged in the 5 well 9. In addition, around the well 9, the top wall 7 of the reservoir is provided with an annular groove 36 which may, for example, be in the shape of a circularly symmetrical cylinder and which is open upwards. A 10 reinforcing ring 37 is engaged in the annular groove 36 so that the annular wall 38 that separates the groove 36 from the well 9 is clamped between the ring 37 and the tubular element 19. This clamping provides sealing between the well 9 and the tubular element 19 merely by 15 contact between these two parts, without requiring an additional gasket. Preferably, the annular groove 36 and the ring 37 are concentric with the well 9 and with the tubular element 19. 20 Advantageously, the tubular element 19 isengaged in snug-fitting manner into the well 9, while the annular face 39 of the ring 37 that faces radially inwards is engaged in tight-fitting manner against the annular face 40 of the groove that faces radially outwards. It should 25 be noted however that it is possible to have some clearance (a few hundredths of a millimeter) between the tubular element 19 and the well 9, the tight-fitting engagement of the ring 37 in the groove 36 compressing the annular wall 38 against the tubular element 19 30 without generating any extension stress in said annular wall. Preferably, the annular face 41 of the ring 37 that faces radially outwards is engaged without being tight fitting in the annular face 42 of the groove that faces 35 radially inwards. More precisely: 8 - the outside diameter of the tubular element 19 may be at least equal to and advantageously substantially equal to the inside diameter of the well 9; - the inside diameter of the ring 37 may be less 5 than (e.g. about 3 to 12 hundredths of a millimeter less than) the inside diameter of the groove 36; and - the outside diameter of the ring 37 may be not more than,-and preferably less than the outside diameter of the groove 36 so that the ring 37 does not generate 10 any extension stresses in the portion of the top wall 7 that is situated outside the groove 36. These various provisions make it possible for excellent sealing to be obtained between the tubular element 19 and the well 9, without any risk of generating 15 micro-cracks in the top wall of the reservoir, in particular in the vicinity of the well 9. Advantageously, the material of which the ring 37 is made must be relatively rigid and capable of withstanding a relatively large amount of elongation, preferably 20 greater than 5%. By way of example, the ring 37 may be made of a semi-crystalline polymer material, e.g. polyoxymethylene (POM) or polyamide, e.g. of the 6-6 type. For the purpose of reducing the number of parts, the 25 ring 37 is made integrally with the head 12 and of said semi-crystalline material. In addition, this material makes it possible to fit the tubular element 19 simply, by force fitting it into a hole 43 in the head 12. Naturally, this embodiment is in no way limiting, 30 and, in particular, it is possible to make the head 12, the ring 37, and the tubular element 19 integrally, and either of metal or of semi-crystalline polymer.