Liquefied Gas-fueled Smoking Lighter Utilizing Piezo-electric Elements As The Voltage Generation Source

Abstract

A liquefied gas-fueled smoking lighter utilizing piezoelectric elements as the voltage generation source comprising a casing, a support frame structure disposed within and secured to said casing, a high voltage generation unit comprising piezoelectric elements received in said frame structure and pinched at their opposite ends by a pressure transfer plate and a washer, an eccentric cam disposed on said pressure transfer plate for applying a pressure to said piezoelectric elements, a valve manipulation lever fixedly mounted on the shaft of said cam and having said cam shaft as the axis of rocking movement, and a valve opening and closing member disposed adjacent to said lever with at least a portion of said member positioned in the path of rocking movement of said lever.

Description

BACKGROUND OF THE INVENTION

The present invention relates to a liquefied gas-fueled lighter of the type in which piezoelectric elements are applied a pressure thereon so as to generate a voltage which is utilized to ignite the fuel gas and more particularly, to improvements in the construction of a mechanism for applying a static pressure on the piezoelectric elements and a burner associated with the mechanism.

Various types of ignition devices utilizing piezoelectric elements as the voltage generation source have been proposed and practically operated. And in such ignition devices the piezoelectric elements are applied a static pressure or a compressive pressure thereon so as to generate a voltage which is utilized as the gas ignition energy. These types of ignition devices have been widely studied and developed for the applications in the field of internal combustion engines as well as those in the field of liquefied gas-fueled lighters to which the present invention pertains. However, any of the conventional piezoelectric type ignition devices is adapted to apply only a compressive pressure on the piezoelectric elements so as to generate a voltage which can be utilized to ignite the fuel. Such an operation of the ignition device merely represents an elementary combination of a piezoelectric element-pressurizing operation and an ignition operation and accordingly, such conventional ignition devices have not been practically available.

Generally, a voltage generated in piezoelectric elements by applying a static pressure or a compressive pressure has a relatively lower ignition energy as compared with that of a voltage generated in the piezoelectric elements by applying a dynamic pressure or an impact force on the elements. Therefore, in order to increase the ignition energy obtainable by the application of a static or compressive pressure on the piezoelectric elements, the voltage capacity of the piezoelectric elements is increased or a stronger static pressure applying mechanism is employed.

However, an ignition device such as a liquefied gas-fueled smoking lighter to which the present invention pertains is of a very small size and accordingly, it is impossible to increase the ignition energy to be generated in the piezoelectric elements by increasing the voltage capacity of the elements. Furthermore, in order to effectively ignite the fuel gas while the gas is flowing as practiced in a liquefied gas-fueled lighter, it is absolutely necessary to provide a improved burner which can maintain the mixing condition of the flowing gas and air in a state optimum for combustion in the vicinity of the burner where the ignition energy is released.

SUMMARY OF THE INVENTION

One object of the present invention is to provide a small size ignition device such as a liquefied gas-fueled smoking lighter in which the mechanism for applying a static pressure on the piezoelectric elements and a valve manipulation mechanism which is adapted to operate in consequence of the operation of the static pressure applying mechanism are operatively disposed in a very limited space within the casing of the lighter and in which the generation of a high voltage and the gas discharge operation are effected in a precisely predetermined timed relation.

Another object of the present invention is to provide a relatively small size ignition device such as a liquefied gas-fueled smoking lighter having a burner which can maintain its mixing function of gas, the flow rate of which is controlled by the valve manipulation mechanism, with air in a condition optimum for combustion of the gas-- air mixture.

According to the present invention, there is provided a liquefied gas-fueled smoking lighter utilizing piezoelectric elements as the voltage generation source, comprising a support frame structure disposed within and firmly secured to the casing of said lighter, a piezoelectric element unit disposed within said frame structure and pinched at its opposite ends by a pressure transfer plate and a washer, an eccentric cam having a support shaft and operatively disposed on said pressure transfer plate for applying a pressure to said piezoelectric element unit, a valve manipulation lever mounted on said shaft of the cam and having its axis of rocking movement on the camshaft, and a valve opening and closing member disposed adjacent to said lever with at least a portion of the member positioned in the path of rocking movement of said manipulation lever.

The above and other objects and attendant advantages of the present invention will be more readily apparent to those skilled in the art from the following description when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate embodiments of the present invention in which:

FIG. 1 is a front elevational view in partial section of one preferred form of liquefied gas-fueled smoking lighter constructed in accordance with the present invention;

FIG. 2 is a side elevational view in section of the lighter of FIG. 1;

FIG. 3 is a fragmentary vertically sectional view on an enlarged scale of one preferred form of burner according to the present invention;

FIG. 4 is similar to FIG. 3, but shows a modified form of burner together with its associated principal parts of the lighter with the latter being shown in elevation on an enlarged scale according to the present invention;

FIG. 5 is a fragmentary elevational view in partial section of a modified form of burner according to the present invention;

FIG. 6 is similar to FIG. 3, but shows a further modified form of burner according to the present invention;

FIG. 7 is a cross-sectional view of a water-repelling electrode mounting member taken along the line A-A of FIG. 6;

FIG. 8 is similar to FIG. 7, but shows a modified form of water-repelling electrode mounting member;

FIG. 9 is similar to FIG. 7, but shows a further modified form of water-repelling electrode mounting member;

FIG. 10 is a fragmentary view of the intermediate spark gap providing structure shown in FIG. 2, on an enlarged scale; and

FIG. 11 is a schematic view of the voltage generation circuit.

PREFERRED EMBODIMENTS OF THE INVENTION

The present invention will be now described referring to the accompanying drawings and especially, to FIGS. 1 to 3 thereof in which one preferred form of liquefied gas-fueled smoking lighter according to the present invention is illustrated. The smoking lighter generally comprises a vertically extending hollow main body or casing 1 and a hollow base mount 2 on which the main body 1 is fixedly mounted, and the main body and base mount provide in cooperation the outer sheath or housing structure of the lighter. The hollow base mount 2 includes an inverted frustoconical section 3, an integral flanged and outwardly threaded cylindrical section 4, an inverted cup-shaped upper cover member 5 having a downwardly flared peripheral edge and a threaded center bore 5' through which the cylindrical section extends, and a cup-shaped lower cover member 6 having an upwardly flared peripheral edge. The flange of the cylindrical section 4 seats on the top surface of the upper cover member 5 surrounding the periphery of the center bore 5'. The main body 1 and base mount 2 are secured together to each other by means of a plurality of setscrews 7. Disposed within the upper cover member 5 is a smaller size inverted cup-shaped insert member 8 having its outer configuration mating with the inner configuration of the inverted cup-shaped upper cover member 5, and the insert member also has a center threaded bore 8' which engages the thread on the periphery of the cylindrical section 4. The insert member 8 is further provided with annular bosses 8" on the lower or inner surface thereof, and each of the bosses is provided with a threaded bore. A connecting member 9 is received in the threaded bore in each of the bosses 8" of the insert member 8 by means of an outwardly threaded boss 9' of the connecting member. Each of the connecting members 9 is further provided with a threaded center bore 9" for receiving a setscrew 10 which extends through the lower cover member 6 from the bottom thereof into the associated threaded bore 9" in the connecting member 9. The height of the connecting members 9 is so selected that the opposite peripheral edges of the upper and lower cover members 5 and 6 may provide a space therebetween for the purpose to be described hereinbelow. An annular decorative ring 11 is disposed between the upper and lower cover members 5 and 6 and has a peripheral flange 11' at its outer periphery extending radially outwardly into the space between the upper and lower cover members 5 and 6. A rectangular cross section chassis 12 extends vertically within the main body 1 and has skirts which extend outwardly substantially at right angles to the respectively associated vertical walls of the chassis and which are secured to the lower end of the main body 1 by means of the setscrews 7 which also connect the main body and base mount together. Supported within the chassis 12 is a high voltage generation device which employs piezoelectric elements as the high voltage-generating source and of which a detailed description will be made hereinbelow. The high voltage generation device generally comprises a support frame structure including an outer frame 13 and an inner frame 13' which houses from top to bottom a shoe 14, an eccentric cam 15 having a shaft for applying a pressure on the piezoelectric members through a pressure transfer plate 16, a piezoelectric element unit including a pair of opposite series-connected piezoelectric elements 17 having a terminal plate 18 disposed between the adjacent ends thereof, a washer 19 and a wedge 20. The outer frame 13 is fixedly secured to the chassis 12 by means of setscrews (only one is shown in FIG. 2) and the inner frame 13' is fixedly secured to the outer frame by suitable means (not shown). The rotational shaft of the eccentric cam 15 extends through the opposite sides of the outer frame 13 and is journaled on bearings (not shown) which are in turn suitably supported in the outer frame 13. An operation lever 21 is snugly fit at its center on the rotational shaft of the eccentric cam 15 for rocking movement together with the camshaft. The operation lever 21 supports at one end, shown as its upper end, an operation member in the form of a roller 22, and the other or lower end of the lever supports a valve manipulation member in the form of a roller 23. As seen in FIG. 1, the main body 1 is provided in one of its sidewalls with an opening 1' and one end wall of the chassis 12 is cut away at the upper end portion so that a lateral thumb piece assembly 24 may be slidably received in the opening 1' and the cutaway portion of the main body and chassis. The thumb piece assembly 24 comprises an outer block 25, an inner block 25' and a stop piece 26 which are integrally secured together by means of setscrews. The inner block 25' is provided at one upper corner with a notch 25" for slidably receiving the roller 22 on the operation lever 21. An L-shaped valve-operating member 27 is pivoted at its lower end to the chassis 12 in a position in which the upper end of the operating member may abut against the lower roller 23 on the lever 21. The lower end of valve-operating member 27 encircles the shank of the nozzle 28 underneath the flange on the nozzle shank which is in turn connected to a liquefied gas fuel reservoir 29 through a conventional spring-loaded valve mechanism including a valve 29 disposed within the reservoir. Thus, when the operation lever 21 is operated so as to pivot the valve operation member 27 in the counterclockwise direction, the lower end of the operation member 27 is caused to push the nozzle up whereby the fuel is allowed to flow from the reservoir 30 through the internally disposed valve mechanism and the nozzle to the ignition section of which description will be made hereinbelow. On the other hand, when the lever 21 is allowed to rock so as to cause the valve operation member 27 to pivot in the opposite or clockwise direction, the operation member 27 pushes the nozzle 28 down to close the valve 29, whereby the flow of the fuel from the reservoir 30 is halted. The valve 29 has a gas flow adjusting ring 31 which is fixedly received in a ring retention opening 32 formed by cutting and bending upwardly or inwardly the bottom wall of the chassis 12. The reservoir 30 extends into the main body 1 at its upper end and at its lower end extends into the sections 3 and 4 of the base mount 2, and is supported in its midsection by means of an elastic member 33 formed of material such as synthetic resin which is retained in the upper inverted frustoconical section 3 of the base mount 2. Disposed within and in communication with the lower end of the reservoir 30 is a fuel injection valve 34 and the extreme lower end of the reservoir 30 is formed with a noncircular projection 35. A gas flow adjusting knob 36 is snugly fit on the projection 35 in the raised center of the lower cover 6 and when the knob 36 is turned in one or another direction so as to cause the reservoir 30 to rotate relative to the gas flow adjusting ring 31 received in the retention opening 32, the flow rate of the gas from the reservoir through the valve 29 and nozzle 28 can be adjusted.

A first electrical conductor 37 extends upwardly along the inner wall of the main body 1 and the upper end of the conductor terminates at a point at a small distance from the upper end of the chassis 12 while the lower end of the conductor is connected to the terminal plate 18. Another electrical conductor 37' having one end connected to anode 39 extends downwardly along the inner wall of the main body 1 and terminates short of the upper end of the conductor 37 thereby to provide an intermediate spark discharge gap 38 between the two conductors, which gap is surrounded by an insulator 38'. The above-mentioned anode 39 is suitably and horizontally supported in an electrode mounting member 40 in which a cathode 41 is also suitably and horizontally supported in a position opposite to and spaced from the anode 39. The cathode 41 is connected to a third electrical conductor 42 which extends downwardly from the cathode along the inner wall of the main body 1 in opposition to and spaced from the conductor 37'. The other end of the conductor 42 is connected to the chassis 12. The electrode mounting member 40 is suitably supported in and depends from the top wall of the main body 1 and has a center gas passage 40'. A gas mixing tube 43 is threadably received in the lower portion of the electrode mounting member 40 so as to form an extension of the gas passage a and a wire mesh 44 is disposed across the junction between the electrode mounting member and the gas mixing tube. A flame spouting nozzle 45 is received at the upper end of the electrode mounting member 40 in communication with the gas passage a thereof. The electrode mounting member 40 has a flared upper end 40' which abuts against the inner side of the top wall of the main body 1 under the force of a spring so that the mounting member may be prevented from spring up of the main body 1. The gas mixing tube 43 is provided with primary air intake bores 46 in the lower portion of the wall thereof and a gas guiding tube 47 is received in the lower portion of the gas mixing tube 43. The gas guiding tube 47 has a constricted lower gas conducting portion which is slidably received in an opening in the top wall of the chassis 12 and has a threaded inner periphery. A connector member 48 is threaded on the gas conducting portion of the gas guiding tube 47 and the connector member receives at a point below the top wall of the chassis 12 one end of a gas conduit 49 the other end of which is connected to the nozzle 28. In other words, the flame spouting nozzle 45, electrode mounting member 40, gas mixing tube 43, gas guiding tube 47 and connecting member 48 are axially aligned with one another so as to provide a unitary burner device. The thus formed burner device is movably disposed between the top wall of the main body 1 and the top wall of the chassis 12 and in addition, by the provision of a compression spring 50 around the gas mixing tube 46 between the underside of the electrode mounting member 40 and the top wall of the chassis 12 so that the entire burner device is normally urged against the top wall of the main body 1, whereby the relation between the various parts of the ignition device may be maintained in a predetermined proper relation.

In operation, when the thumb piece assembly 24 which is normally held in the position of FIG. 1 is forced inwardly under the force of the user's finger such as the thumb toward the opposite inner wall of the main body 1, the roller 22 at the upper end of the operation lever 21 which is received in the notch 25" in the inner block 25 is pushed whereupon both the operation lever 21 and eccentric cam 15 which is fitted in the lever are caused to rock in the clockwise direction as seen in FIG. 1. The clockwise rocking movement of the lever 21 and eccentric cam 15 causes the cam to squeeze the piezoelectric elements 17 through the pressure transfer plate 16 to generate a high voltage the positive polarity of which is conducted through the conductor 37, intermediate spark discharge gap 38 and the conductor 37' to the anode 39. On the other hand, the opposite or negative polarity of the voltage is conducted through the chassis 12 and conductor 42 to the cathode 41, whereby sparks are struck out across in the spark discharge gap provided by the opposite electrodes 39 and 41. Simultaneously, the rocking movement of the lever 21 in the clockwise direction also causes the valve manipulation member 27 which is engaged by the lower roller 23 on the lever 21 to rock in the counterclockwise direction, whereby the lower end of the member pushes the nozzle 28 up whereupon the pressurized gas is allowed to flow from the reservoir 30 through the valve 29 and nozzle 28 into the gas conduit 49 which conducts the gas to the gas mixing tube 43 where the gas is mixed with the primary air flowing into the gas mixing tube via the primary air intake bores 46. The gas-- air mixture rises up to the spark discharge gap between the electrodes 39 and 41 and is ignited by the sparks being struck across the spark discharge gap in the manner mentioned above and flames are spouted out of the upper end of the flame spouting nozzle 45.

FIG. 3 shows a modified form of burner suitably employed in the lighter shown in FIGS. 1 and 2 according to the present invention. The burner generally comprises an open end upper cylindrical section 51, a coaxial open end lower cylindrical section 52 having its upper end threadedly received in the lower end of the upper cylindrical section, and a bottom member 53 having its constricted upper end snugly pitted in the lower end of the lower cylindrical section 52 and having a center gas intake opening 54. The pair of discharge electrodes 39 and 41 are received in a pair of diametrically opposite bores formed in the walls of the upper section 51 and the electrodes are horizontally disposed in an opposite and spaced relation from each other with their fore ends projecting into a gas passage a in the upper section so as to provide a spark discharge gap therebetween. The electrode 39 is connected to the negative side of the voltage generation source as shown in FIG. 2 and the other electrode 41 is connected to the opposite side of the source. As seen in FIG. 3, the anode 41 is received in a suitable insulating member 55 which is in turn received in the bore of the wall of the upper cylindrical section 51. A wire mesh 51a is disposed in the junction between the upper and lower cylindrical sections 51 and 52 across the gas passage a. The wire mesh 51a may be replaced by a porous plate or any other suitable bored element if desired. The lower cylindrical section 52 is provided with primary air intake bores 46' in the wall thereof in the same manner as mentioned in the corresponding part of the embodiment of FIGS. 1 and 2. The bottom member 53 further has a depending further constricted extension 53' at the bottom thereof, and the upper end of the gas conduit 49 is fitted on the extension 53'. Thus, it will be understood that when the reservoir is opened in the manner as mentioned above in connection with the preceding embodiment the fuel from the reservoir is spouted from the reservoir, through the valve 29 and nozzle 28 and gas conduit 48 into the gas intake opening 54 in the bottom member 53 into the lower section 52 where the gas is mixed with the primary air flowing into the section 52 via the primary air intake bores 46'. The gas-- air mixture rises up through the lower section 52 and wire mesh 40 into the upper section 51. As the mixture passes through the wire mesh 51a the mixture impinges against the mesh so as to generate a turbulent flow in the mixture whereby the gas and air can be fully mixed together. The thus formed gas-- air mixture then flows upwardly through the upper section of the gas passage a and finally reaches the top of the burner. When a high voltage is applied across the electrodes 39 and 41 in the manner mentioned in connection with the preceding embodiment while the mixture is passing through the passage a, sparks strike out in the spark discharge gap between the electrodes 39 and 41 and thus, the gas-- air mixture is explosively ignited by the sparks to discharge flames which then spout out of the upper end of the burner. With the construction of the burner mentioned just above, the gas and air can be positively mixed together to a condition suitable for ignition by the discharge sparks as they pass through the wire mesh 51a. Furthermore, the electrodes 39 and 41 can be positively prevented from being contacted by the successive flames whereby the possibility of erosion of the electrodes may be limited to a minimum degree. In addition, the danger of the electrodes being struck by foreign matter can be prevented which will otherwise have undesirable effects on the function of the discharge spark gap.

FIG. 4 shows a further modified form of burner according to the present invention which can positively ignite the gas even when sparks at relatively low discharge voltages are struck out. The reservoir 130 of FIG. 4 is provided with a first valve 129 and a second valve 129' which are adapted to be opened so as to allow the gas to flow out of the reservoir when their respective nozzles 128 and 128' are lifted up. A horizontally movable valve operation member 58 is horizontally disposed above the two valves 129 and 129' for operating the valves and has first and second valve opening and closing members 59 and 60 each of which has respective elongated guide slots which encircle and engage the valves respectively. The first valve opening and closing member 59 has a stepped configuration at the bottom thereof and the second opening and closing member 60 has an upwardly arched portion in the center of the bottom as shown in FIG. 4. The valve operation member 58 further has an ear 58' to which a cam 115 is pivoted for pivotal movement in a limited distance. Disposed above said valve operation member 58 is an L-shaped frame member 61 the vertical arm of which has a piezoelectric element unit 17' secured thereon, and the other or horizontal arm of the frame member has an impact delivery member 62 pivoted thereto. As seen in FIG. 4, the impact delivery member 62 is pivoted at its upper end to and depends from the fore end of the horizontal arm of the frame member. A tension spring 63 is anchored at one end to the vertical arm of the frame member 61 and at the other end to the impact delivery member 62 below the pivoting point so as to normally urge the impact delivery member toward the piezoelectric element unit 17'. A main gas conduit 149 is connected at its lower end to the first nozzle 128 associated with the first valve 129 and extends along the vertical wall of the main body (not shown). The upper end of the gas conduit 149 first bends at right angles with respect to the vertically extending midsection thereof to extend horizontally through an opening in the wall of the burner which, in this embodiment, comprises an open end single cylindrical section 151 and a bottom member 153 having a depending constricted extension 153'. The extreme upper end of the gas conduit 149 again bends at right angles with respect to the horizontal upper section thereof and extends upwardly to open at the open upper end of the burner as the gas nozzle 145. Thus, when the valve operation member 58 is moved in the direction of the arrow x as seen in FIG. 4 to a predetermined distance by any suitable means (not shown), the first valve opening and closing member 59 moves along the nozzle 128' in the same direction by means of its slot until the outer or higher portion of the member 59 engages and pushes up the flange on the shank of the associated nozzle and accordingly, opens the valve associated with the nozzle 128 and at the same time the second valve opening and closing member 60 is also moved along the associated nozzle 128' by means of its slot until the center arched portion engages and pushes up the flange on the shank of the associated nozzle 128' thereby to open the associated valve. When the valves are opened in the manner mentioned above, a portion of the gas is allowed to flow from the reservoir 130 through the first valve, nozzle and gas conduit 149 and spouts at the spouting nozzle 145 and at the same time another portion of the gas is allowed to flow from the reservoir, through an auxiliary conduit 149' and spouts into the gas passage a in the cylindrical section 151. When the valve operation means 58 is moved in the direction of arrow x as mentioned above, simultaneously, the cam 115 pivoted to the operation means 58 is moved in the counterclockwise direction so as to cause the impact delivery member 62 to pivot away from the piezoelectric element unit in the counterclockwise direction while allowing the spring 63 to store an impacting energy therein. As the operation means 58 is further moved in the same linear direction, the impact delivery member 62 will finally disengage from the cam 115 whereupon the impact delivery member 62 is caused to rapidly move toward the piezoelectric element unit so as to strike the piezoelectric elements with a high striking force by the action of stored energy in the spring 63 which applies an internal strain to the piezoelectric elements to generate a high voltage therein. The thus generated high voltage is transmitted through the conductors which are respectively associated with the opposite electrodes to strike out sparks across in the spark discharge gap between the electrodes The thus struck sparks explosively ignite the gas which has been previously mixed with the primary air flowing into the cylindrical section 151 via the air intake bores 146 as the gas was entering the cylindrical section. The thus ignited gas and air mixture then surrounds and ignites the gas flowing out of the flame spouting nozzle 145. As the operation means 58 is further moved in the direction of arrow x the center arched portion of the second valve opening and closing member 60 moved past the associated nozzle 128' to allow the nozzle to descend, whereby the second valve 129' is closed to halt the flow of the auxiliary gas from the reservoir 130 while leaving the main gas to continue to flow from the reservoir 130 through the valve 129 and gas conduit 149 to the flame spouting nozzle 145 so as to support the combustion of the gas at the flame-spouting nozzle. When it is desired to extinguish the flames, the operation means 58 is moved back in the direction of arrow y until the first and second valve opening and closing members 59 and 60 again assume the position as shown in FIG. 4 in which the higher lever portion of the first member 59 has passed the nozzle 128 to allow the nozzle to descend for closing the associated valve and the center arched portion of the second valve opening and closing member 60 has also passed the associated nozzle 129' to allow the nozzle to descend for closing the associated valve, whereby the flow of the gas from the reservoir can be perfectly and completely halted and the cam 115 again comes to engage the impact delivery member 62 in which the various parts of the ignition device are ready for a next cycle of operation.

FIG. 5 shows a further modified form of burner which is substantially identical with that of FIG. 4 except that the single cylindrical section 151 of FIG. 4 is replaced by a single cylindrical section 251 formed of a suitable electrically insulative material and that the main gas conduit 249 formed of an electrically conductive material concurrently serves as the negative electrode adapted to be connected to the negative side of the piezoelectric element unit thereby to eliminate the electrode 139 of FIG. 4.

FIG. 6 shows a further modified form of burner which can sufficiently sustain a high heat generated when the gas is burned. In the embodiment of FIG. 6, the burner comprises a single cylindrical section 351 formed of a suitable heat-resistant material such as steatite, and the section receives an electrically insulative electrode mounting member 340 in its openings formed in the wall thereof which mounting member is formed of a suitable water-repelling material such as resin. The electrodes 339 and 341 are received in the water-repelling mounting member 340 in the same opposite relation in the section 351 as mentioned in the preceding embodiments. The electrodes 339 and 341 are electrically connected to the opposite polarity sides of the piezoelectric element unit (not shown). The embodiment of FIG. 6 is especially adapted to prevent moistening substances from adhering to the areas at and adjacent to the portions of the wall of the cylindrical section where the electrodes are mounted. The construction and arrangements of the remaining parts of the burner of FIG. 6 are substantially the same as those of the corresponding parts of the preceding embodiments. FIG. 7 is a cross section of FIG. 6 taken along the line A-A of the latter.

FIG. 8 is a cross section of a modified version of the electrode mounting member as shown in FIGS. 6 and 7 and in the embodiment of FIG. 8, the electrode mounting member 440 comprises two semicircular half-sectors, that is, a water-repelling sector 451 and a heat-resistant sector 451' which receive the opposite electrodes 439 and 441 substantially in the same relation as in the preceding embodiments.

FIG. 9 is a cross section view of a further modified version of the electrode mounting member as shown in FIGS. 6 and 7 and in the embodiment of FIG. 9, the electrode mounting member 540 comprises four sectors, that is, two water-repelling sectors 551 and 551 and two heat-resistant sectors 551' and 551' which are alternately disposed in a circle. With the construction of the electrode mounting member of FIG. 9, the distance between the opposite electrodes 539 and 541 is made shorter than that between the opposite water-repelling sectors 551 and 551 whereby the two electrodes can be satisfactorily maintained in an insulative and nonconductive relation even if the lighter in which the electrode mounting member of FIG. 9 is incorporated is operated under high moisture conditions. When the gas lighter as shown in FIGS. 1 and 2 employ any one of the electrode mounting members as shown in FIGS. 3 to 9 inclusive, the gas from the gas conduit 49 or 149 first passes through the gas intake opening in the bottom member of the burner into the lower portion of the cylindrical section or sections of the burner and the gas rises upwardly within the burner section or sections at a high velocity while being mixed with the primary air flowing into the burner section or sections via the primary air intake bores in the wall of at least one of the section. The gas-air mixture then continues to rises up to impinge against the wire mesh 51a whereby a turbulent flow is generated in the mixture and the gas and air can be further mixed together to a higher degree. The highly mixed fluid flows up to the discharge electrodes 39 and 41 in the upper portion of the burner section or sections whereupon the electrodes which have been applied high voltages thereupon strike out sparks across therebetween so as to ignite the gas and air mixture in an explosive manner. The thus ignited fluid mixture spouts out of the flame spouting nozzle as flames. Therefore, when the electrodes are held in position in the wall of the burner which includes a heat-resistant area or areas formed of heat-resistant material such as pottery or porcelain and a water-repelling area or areas formed of water-repelling insulative material such as resin with a portion of the electrode protruding into the gas passage within the burner section or sections and with at least a portion of the water-repelling area or areas positioned between the electrodes, even when the lighter is operated under high moisture conditions the areas of the burner wall where the electrodes are supported can be prevented from being contacted by moistening substances. Thus, the intermediate areas between the electrode mounting areas in the burner wall can be at all times maintained in an electrically insulative state and the high voltages applied on the electrodes can positively strike out discharge sparks thereby to assure positive ignition of the gas flowing through the burner. And since the areas other than the water-repelling areas and especially, the areas adjacent to the flames spouting nozzle, are formed of heat-resistant material, the possibility of melting away, deformation and/or burning of the nonwater-repelling areas by the flames can be minimized thereby to provide a durable and reliable burner device.

FIG. 10 shows the intermediate discharge gap arrangement shown in FIG. 2 on an enlarged scale and in the arrangement of FIG. 10 the conductor 37 having its lower end connected to the terminal plate 18 (FIG. 2) and the other conductor 37' having its upper end connected to one of the electrodes are disposed in an opposite to and spaced from one another relation so as to provide a spark discharge gap therebetween. The opposite ends of the conductors 37 and 37' have spherical electrodes 37a and 37b, respectively secured thereto and the gap is shielded by an insulating cover 38 from the atmosphere whereby corona discharge loss in the high temperature atmosphere is prevented. The spherical configuration of the electrodes 37a and 37b is selected for the purpose that the electric field across the gap be maintained uniform and corona discharge loss be decreased. The spherical electrodes 37a and 37b are received in the opposite ends of the conductors 37 and 37' and held in position by adhesive.

FIG. 11 schematically shows the circuit leading to the piezoelectric elements of the above-mentioned various embodiments. For simplicity of the illustration and description, the circuit is shown as being employed in connection with the embodiment of FIGS. 1 and 2.

As clear from the foregoing description, when the thumb piece assembly 24 is pushed inwardly toward the opposite inner wall of the main body 1, the valve manipulation roller 22 at the upper end of the lever 21 which rides on the notch 25" of the inner block 25' is also pushed inwardly and accordingly, the lever is rocked in the clockwise direction. The rotational movement of the lever 21 in the clockwise direction causes the roller 23 at the lower end thereof to pivot the valve opening and closing member 27 in the counterclock direction. The pivotal movement of the member 27 in the counterclock direction causes its lower end to lift up the nozzle 28 against the force of the spring within the reservoir whereupon the gas is allowed to flow from the reservoir 30 through the valve and nozzle 28. The gas then flows upwardly through the gas conduit 49 into the gas and air mixing tube 43 where the gas is mixed with the primary air flowing into the tube 43 via the primary air intake bores 46. The rocking movement of the lever 21 in the clockwise direction also simultaneously causes the eccentric cam 15 which is firmly secured to the lever to rotate in the clockwise direction so that the cam 15 may squeeze the piezoelectric elements 17 together and a high voltage is generated in the piezoelectric element unit. The positive polarity of the voltage is conducted from the terminal plate 18 through the conductor 37, spherical electrodes 37a and 37b and conductor 37' to the electrode 39 and the negative polarity voltage is conducted from the outer ends of the elements through the chassis 12 and conductor 42 to the electrode 41 whereupon sparks are struck out across the spark discharge gap between the opposite electrodes. The thus struck sparks ignite the gas-air mixture passing upwardly through the gap. The thus ignited gas and air mixture will forth out flames which spout out of the flame spouting nozzle 45.

Thus, according to the present invention, in the type of fuel ignition device adapted to ignite the flowing fuel by a high voltage spark discharge which takes place as the piezoelectric elements are applied a pressure thereon or the applied pressure is released therefrom, the ignition electrodes are electrically connected to the piezoelectric elements in a high voltage circuit and an intermediate gap provided by the spherical electrodes are provided in series with the ignition electrodes in the circuit. It should be understood that when a pressure is applied on the piezoelectric elements a high voltage is generated and sparks are struck out across the spark discharge gap between the electrodes supported in the electrode mounting member to ignite the gas and air mixture, but when the pressure is released from the piezoelectric elements a lower voltage is generated which is insufficient to ignite the gas-air mixture, but sufficient to strike sparks across the intermediate spark discharge gap as the piezoelectric elements gradually return to their normal or nonpressurized state. The intermediate gap is airtightly shielded by the insulating cover from the atmosphere and accordingly, the electric field across the intermediate gap can be maintained substantially uniform and has a stabilized dielectric breakdown voltage with substantial reduction of loss of electric charge due to corona discharge thereby to assure a high discharge energy. In addition, since the intermediate gap is airtightly shielded by the insulating cover from the atmosphere, even when the ignition device is operated under a high moisture atmosphere the loss of electric charge due to corona discharge can be substantially reduced and accordingly, the ignition device can positively ignite various types of fuel.

Although certain preferred embodiments of the present invention have been described and illustrated herein, it is to be understood that they are illustrative in nature and not to be necessarily limiting upon the scope of these teachings in their broader aspects. Many additional variations within the scope of the appended claims will occur to those skilled in the art.

Claims

I claim:

1. A liquefied gas-fueled smoking lighter utilizing piezoelectric elements as the voltage generation source comprising a support frame structure disposed within and firmly secured to the casing of said lighter, a piezoelectric element unit disposed within said frame structure pinched at its opposite ends by a pressure transfer plate and a washer, an eccentric cam secured to a support shaft and operatively disposed on said pressure transfer plate for applying a pressure to said piezoelectric element unit, a valve manipulation lever also secured to said shaft of the cam for pivotal movement about the axis of the cam shaft, and a movable valve opening and closing member disposed adjacent to said lever with at least a portion of the member disposed in the path of pivotal movement of said manipulation lever, whereby movement of said valve opening and closing member and pressure on said piezoelectric element unit will be simultaneously affected by pivotal movement of said lever.

2. A liquefied gas-fueled smoking lighter utilizing piezoelectric elements as the voltage generation source comprising a support frame structure disposed within and firmly secured to the casing of said lighter, a piezoelectric element unit disposed within said frame structure pinched at its opposite ends by a pressure transfer plate and a washer, an eccentric cam having a support shaft and operatively disposed on said pressure transfer plate for applying a pressure to said piezoelectric element unit, a valve manipulation lever mounted on said shaft of the cam and having its axis of rocking movement on the cam, a burner provided in said casing above said valve manipulation lever and having primary air intake bores, said burner including a gas guiding tube coaxially disposed therein, and a valve opening and closing member disposed adjacent to said lever with at least portion of the member disposed in the rocking movement passage of said manipulation lever.

3. A liquefied gas-fueled smoking lighter utilizing piezoelectric elements as the voltage generation source as set forth in claim 2, in which a pair of discharge electrodes are electrically connected to said piezoelectric element unit and disposed in said burner above said primary air intake bores with a portion thereof extending into a gas passage defined with the burner.

4. A liquefied gas-fueled smoking lighter utilizing piezoelectric elements as the voltage generation source as set forth in claim 3, in which said burner includes a porous member in the form of wire mesh which extends across said gas passage at a point above said primary air intake bores and below said discharge electrodes.

5. A liquefied gas-fueled smoking lighter utilizing piezoelectric elements as the voltage generation source as set forth in claim 3, in which said burner includes sections comprising heat-resistant material such as porcelain and water-repelling material such as resin, respectively, and said pair of discharge electrodes are received in said burner with at least a portion of the electrodes projecting into said gas passage, at least a portion of said water-repelling section being disposed between said discharge electrodes.

6. A liquefied gas-fueled smoking lighter utilizing piezoelectric elements as the voltage generation source as set forth in claim 2, in which said gas guiding tube is utilized as a main gas spouting means and said gas passage is utilized as an auxiliary gas means.

7. A liquefied gas-fueled smoking lighter utilizing piezoelectric elements as the voltage generation source as set forth in claim 3, in which said pair of discharge electrodes provide a spark discharge gap which strikes out sparks for igniting a flow of gas passing through said gas passage and an intermediate auxiliary gap is series connected to said discharge gap and said piezoelectric element unit.

8. A liquefied gas-fueled smoking lighter utilizing piezoelectric elements as set forth in claim 7, in which said intermediate auxiliary gap is provided by a pair of opposite spherical electrodes.