US3494710A

US3494710A - Piezoelectric gas lighter

Info

Publication number: US3494710A
Application number: US691530A
Authority: US
Inventors: Takeshi Inagaki
Original assignee: Individual
Current assignee: Individual
Priority date: 1967-02-24
Filing date: 1967-12-18
Publication date: 1970-02-10
Anticipated expiration: 1987-02-10
Also published as: DE1632658A1; GB1162442A; FR1562861A

Description

'FebQiO, 1970 I TAKESHIYINAGARI I 3,494,710

PIEZOELECTRIC GAS LIGHTER Filed Dec. 18, 1 967 4 Sheets-Sheet 1 Feb; .10, 1970 TAKESHI INAGAKI 9 0 PIEZOELECTRIC GAS LIGHTER Filed Dec. 18, 1967 4 Sheets-Sheet B Feb.1b; 1970"- PIEZOELECTRIC GAS LIGHTER Filed De c. is, 1967 4 Sheets-Sheet a TYAKESHI l lfl AG AKl I 3,494,710v A I Feb. 10, 1970 ITAKESHI INAGAKI 3,494,710

PIEZOELECIRIC GAS LIGHTER Filed'Dec. 18 1967 4 Sheets-Sheet 4 United States Patent 3,494,710 PIEZOELECTRIC GAS LIGHTER Takeshi Inagaki, 16 Senjunakai-cho, Adachi-ku, Tokyo, Japan Filed Dec. 18, 1967, Ser. No. 691,530 Claims priority, application Japan, Feb. 24, 1967, 42/15,493; June 17, 1967, 42/38,722 Int. C]. 13231 2/00 U.S. Cl. 431-143 Claims ABSTRACT OF THE DISCLOSURE This invention relates to a liquefied gas lighter and more particularly to a piezoelectric gas lighter in which a gaseous fuel is ignited by a spark produced from a piezoelectric element contained therein.

Lately, various kinds of piezoelectric gas lighters which have a piezoelectric ignition system as a substitute for a flint and sparking wheel have been proposed. In view of the fact that the piezoelectric element can avoid the trouble of replacing a flint and has a semi-permanent life, the piezoelectric gas lighters are much appreciated. In practice, however, it is diflicult to apply a piezoelectric ignition system to a compact gas lighter of pocket type and, therefore, most of the piezoelectric gas lighters which have heretofore been marketed are of large type, such as table lighter.

The piezoelectric elements produced nowadays have, in general, a high energy conversion efficiency; for example, a voltage of 15-20 kilovolts can be generated from a piezoelectric element which is fabricated from a lead zirconate-lead titanate polycrystal and has a size of 3.5 mm. diameter x mm. length. However, the voltage developed is proportional to the pressure applied, and such high voltage is generated only when suflicient pressure is applied to the piezoelectric element. Therefore, even with any existing excellent piezoelectric element, it is impossible to generate a voltage required for igniting the gaseous fuel without a suitable mechanical means operative for producing a suflicient pressure. Such mechanical means generally needs a relatively large construction, so it has been difiicult to be contained in a compact gas lighter. It is the very reason why it has heretofore been diificult to produce a pocket type piezoelectric gas lighter.

It is therefore one object of the present invention to provide a pocket type piezoelectric gas lighter which is as small as orsmaller than conventional flint gas lighters of pocket type.

Another object of the present invention is to provide a lighter of the kind described which can be easily disassembled and reassembled.

A further object of the invention is to provide a lighter of the type stated which can effect ignition of the gaseous fuel by a single action performed by the user without fail.

Another object is to provide a piezoelectric gas lighter of the character stated which is light in weight and durable.

s A still further object of the invention is to provide a lighter of the character described which is simple in construction and which can be manufactured and sold at a reasonable cost.

Further objects, features and advantages of the invention will become apparent from the following detailed description and annexed drawings in which:

FIGURE 1 is a perspective view of a lighter embodying the present invention;

FIGURE 2 is an enlarged vertical sectional view of the lighter shown in FIG. 1, with a fingerpiece, illustrating the internal structure thereof;

FIGURE 3 is an enlarged perspective view of a casing unit of the lighter consisting of a casing and the fingerpiece;

FIGURE 4 is an enlarged perspective view showing a fuel reservoir unit and an ignition unit of the lighter shown in FIG. 2;

FIGURE 5 is an enlarged cross-sectional view illustrating an actuating mechanism in association with the fingerpiece;

FIGURE 6 is a cross-sectional view taken along the line VI-VI of FIG. 5;

FIGURE 7 is an enlarged exploded view of a fingerpiece supporting unit; and

FIGURE 8 is an enlarged exploded View of the ignition unit.

In FIGURES 1 to 8, like portions or parts are designated with like numerals.

Referring to FIGURES 1 to 3, one embodiment of the present invention is illustrated as applied to a pocket type liquefied gas lighter 10 having a casing 11 of a rectangular shape. The casing 11 is provided at one end of its top with an opening 12 for discharging a flame from a burner. FIG. 2 illustrates the state in which a fuel reservoir unit 1311 and a ignition unit 14a shown in FIG. 4 are encased by a casing unit shown in FIG. 3. To the lower opening of the fuel reservoir 13 is fixed a concave-shaped base plate 15 which functions as a common bottom wall both for the reservoir and the casing 11. The reservoir .13 is provided at its upper portion with a burner valve 17 having a burner nozzle 16 and an adjusting wheel 18 for regulating the height of flame from the burner nozzle, and also at the bottom portion with a filling valve 19. On a portion 20 of the bottom plate or the bottom wall 15, adjacent to the reservoir, is mounted the ignition unit 14a by means of a screw 22 which is adapted to engage a tapped hole 21.

As shown in FIG. 4, the ignition unit 14a consists essentially of a piezoelectric element 23, a hammer 24, a coil spring 25, a support 26 and a slidable member 27 which are all disposed within an inverted U-shaped frame 14 in the manner depicted. The hammer 24 is resiliently movably supported by the coil spring 25 axially pierced by the support 26 and is adapted to strike against the piezoelectric element 23 by the action of said spring. The hammer 24 has a vertical bore 24' which opens at its lower end and vertically slidably engages with the upper portion of the support 26 so that the hammer may be vertically guided by the support during its movement. The slidable member 27 is at its cut-out portion 48 in releasable engagement with a lateral pin 28 projecting rearwardly from the hammer 24. The fuel reservoir 13 has at its side wall a U-shaped connecting lug 29, to which the frame 14 is connected by means of a screw 30, thereby enabling the ignition unit or igniting mechanism assembly 1411 to be securely mounted on the bottom plate 15 in cooperation with the screw 22.

When the ignition unit 14a, which is mounted on the bottom plate 15 together with the fuel reservoir unit 13a, is inserted, as shown in FIG. 2, into the casing unit 11:: through from the lower opening thereof, the slidable member 27 is brought, at its tongue-like lug 31, into engagement with a pair of

rectangular projections

33, 33 which extend from a fingerpiece 32 provided on the rear wall of the casing 11. Accordingly, when the fingerpiece is depressed, the hammer 24 is forced to be lowered to compress the coil spring 25 for energization.

Referring now to FIGURES to 7, the fingerpiece 32 of triangular cross-section is so attached to the casing 11 as to cover a vertically elongated opening 34 formed in the rear wall of the casing. The

rectangular projections

33, 33 project from a U-shaped intermediate member 35 having legs 35a, 35b which are inserted respectively into a pair of horizontal slits 36a, 36b of a resilient slide 36, said legs projecting rearwardly out of the opening 34 of the casing 11 and pressing said slide 36 against the inner face of the side wall of the casing. The projecting legs 35a, 3512 are inserted into a pair of slits 37a, 37b of a base plate 37 of the fingerpiece. The U-shaped member 35, the slide 36 and the base plate 37 are fastened together by means of a screw 38. Thus, the fingerpiece 32 is vertically movably attached to the rear side of the casing by means of a screw 39 which is in threaded engagement with the U-shaped member 35. A a result, the fingerpiece 32 and the U-shaped member 35 can be vertically moved between the upper and lower limits of the opening 34.

The slidable member 27 has at its upper portion a pair of ears 27a, 27b which are inserted respectively into a pair of vertical guide slits 43, 43' formed in upper portions 14'a 14b of the side walls 14', 14" of the frame 14 that protrude rearwardly, so that the slidable member 27 can slide vertically along said slits. The slidable member 27 is upwardly urged by means of a coil spring 45 the lower end of which is connected to the slidable member at 46, and the upper end of which to a shaft 44 which traverses the

side walls

14, 14" of the frame 14. To the shaft 44 is secured a base portion of a wire spring 47, of which the tip portion 47' bears against the intermediate portion of the slidable member 27 so that a roller 42, which is rotatably attached to the leg portions 40, 40' of the slidable member 27 by means of a pivot pin 41, may be brought into slidable contact with guide edges 14c, 14d of the frame 14.

Referring now to FIG. 8, the ignition unit previously shown in FIG. 4 is dismounted and illustrated by parts, which can be readil reassembled in accordance with the manner as will be hereinafter described.

The

side walls

14, 14" of the frame 14, which are connected by an upper wall 14e integrally formed therewith, have at their lower portions the vertical guide edges 14c, 14d for the roller 42 that leads to sled-like curved edges 1411, 141. The piezoelectric element 23 packed in a suitable plastic mold has its lower end 23' exposed downwardly.

A supporting plate 49 has in its central portion a circular aperture 50 in which is inserted the lower end 23' of the piezoelectric element '23. The supporting plate 49 is secured to the frame 14 by inserting a pair of ear portions 49a, 49b of the plate in a pair of slits 51 of the frame, respectively so as to secure the element 23. The slidable member 27, coil spring 45 and wire spring 47 are disposed within to the frame 14 in the manner described in connection with FIGURES 5 and 6.

The support 26 receives at its boss portion 26 a lower supporting plate 52 which is fastened together with a washer 53 by means of a nut 54 adapted to engage a thrreaded portion 26" of the support 26. On the support 26 is axially mounted a coil spring 25, which rests at its lower end on the supporting plate 52 and bears at its upper end against the hammer 24. The supporting plate 52 is secured to the frame 14 by inserting a pair of ear portions 52a, 52b thereof in a pair of slits 52', 52" of the frame. Subsequently, the side walls 14', 14" of the frame are fastened by means of a screw 55 which passes through a pair of holes 54, 54' thereof. To the lower end of the frame 14 is attached a concave-shaped bottom member 56, through the medium of which the frame 14 is attached to the bottom plate of the fuel reservoir 13 at by means of a screw 22 screwed into a tapped hole 57 of the boss portion 57 of the support 26 through a hole 21 of the bottom plate and a hole 56 of the bottom member.

A valve opening lever 58 has a forked end portion 58' and a pair of tail portions or legs 58a, 58b and is pivotally mounted at its legs on the upper portions of the walls of the frame 14 by means of pivots 60 passing through holes 59 of the legs and holes 59 of the frame, respectively so that the curved end portions of the legs 58a, 58b may obliquely downwardly extend across the vertical guide slits 43, 43. The lever 58 is, as shown in FIG. 2, at its forked portion 58, in engagement with a neck portion 16' of the burner nozzle 16.

Indicated by numeral 61 is electrode, the base portion 61b of which is secured to the frame 14 at 61b by means of a screw 62, and the end point 610 of which projects laterally, as clearly shown in FIG. 2, just above the burner nozzle 23 so as to be located opposite to the other electrode 23a extending from the piezoelectric element 23, forming a spark gap. Between a top portion Me of the ignition unit and an upper wall of the casing 11 is disposed a suitable cushion 63 so as to absorb the impact against the casing that is produced when the hammer strikes against the piezoelectric element. When the assembly of the ignition unit and the reservoir unit 13a is inserted in the casing through the lower, opening thereof, an adjusting wheel 18 with its edge milled is inserted in an opening 64 of the casing, and attached, at its internally fluted bore 18a, to a burner nozzle 16. Thereupon, the assembly of the two

units

14a, 13a is inserted further in thecasing till the upper edge 1501 of the upstanding peripheral wall of the bottom plate 15 fits the edge of the lower opening 11' of the casing 11. Then, the screw 65 is screwed into a tapped hole 67 formed in a tongue-like portion 56a of the bottom member 56 of the frame 14, through an aperture 66 of the casing 11. Thus, the assembling operation of the piezoelectric gas lighter, which comprises the casing unit 11a, the reservoir unit 13a and the ignition unit 14a is completed.

In operation, when the fingerpiece 32 is manually depressed by pressing an upper surface 32a thereof, the slidable member 27 is depressed against the action of the spring 45 and, at the same time, the hammer 24 having a lateral pin 28, which is in releasable engagement with a cut-out portion 48 of the member 27, is lowered by said member compressing the coil spring 25. Also, when the slidable member is lowered, its ears 27a, 27b are adapted to slide down along the guide slits 43, 43 of the frame and to press down the curved legs 58a, 58b of the valve opening lever 59, causing the forked portion 58' of the lever to be raised. As a result, the burner valve 17 is opened, and the fuel in the reservoir 13 is discharged through the nozzle 16.

As the slidable member 27 is further lowered along the guide edges 14c, 14d of the frame 14, its lower end is forced to mount the sled-like curved end portions 14h, 14i with its roller 42, thereby causing the pin 28 of the hammer 24 to be released from the engagement with the cut-out portion 48 of the slidable member 27. The moment the pin is released, the hammer is caused to spring up by the action of the coil spring 25 energized and strikes against the lower end 23 of the piezoelectric element 23 to thereby produce a spark at the spark gap between the

electrodes

23a, 61a, causing the gas flowing out of the burner nozzle 16 to be ignited. The flame thus produced is discharged through an opening 12 of the casing 11.

On releasing the pressure applied to the fingerpiece 32, the slidable member is returned to its normal position together with the fingerpiece by the action of the spring 45. In the normal position, the slidable member is brought, at its cut-out portion 48, into engagement with thepin 28 of the hammer again. At the same time, the legs 58a, 58b of the valve opening lever 58 are released from the pressure exerted by the ears 27a, 27b and the forked portion of the lever is returned to its original position, thereby causing the burner valve 17 to be automatically closed.

As may be seen from the foregoing, the piezoelectric liquefied gas lighter according to the present invention is fabricated-by three simplified units, the casing unit 11a, the fuel reservoir unit 13a and the ignition unit 14, and accordingly, it can be readily dismounted and reassembled. Consequently, when there is some trouble with the lighter, the defective unit or part thereof can be readily repaired.

What-is claimed is:

1. A dismountable piezoelectric liquefied gas fueled lighter comprising a casing unit and an assembly composed of 'a fuel reservoir unit and an ignition mechanism unit saidassembly being removably mounted in said casing unit," said ignition mechanism unit .being detachably connected to said fuel reservoir unit in a side-by-side relationship therewith, said casing unit including a casing, having a; lower opening through which said assembly is removably mounted in the casing, and manually operable actuating means vertically movably mounted on said casing, said; fuel reservoir unit including a fuel reservoir, having a bottom wall common to said casing and adapted to closthe lower opening thereof a burner-valve assembly and a filling valve assembly, the two said assemblies being fixed to the top and the bottom wall of said reservoir, respectively, said ignition mechanism unit including a vertically elongated U-shaped frame, said frame having side walls formed with sloping cam surfaces at the lower portions ithereof, a piezoelectric element removably secured to; an upper portion of said frame therewithin, a pair off'electrodes in circuit with said piezoelectric element and set so as to provide a spark gap above the burner of said burner-valve assembly and impacting means operatively connected with said manually operable actuating means, said impacting means including hammer means having a vertical bore opening at its lower surface, and being vertically reciprocably disposed underneath said piezoelectric element within said frame by means of a stationary vertical guide post extending into the vertical bore of; said hammer means, said impacting means also including coil spring means mounted concentrically with said guide post in said frame and abutting at its upper end against the underside of said hammer means to normally bias said hammer means upwardly toward said piezoelectric element and means vertically slidably fixed to said frame and arranged so as to be engageable with said hammer means to lower the latter along said vertical guide post in association with said manually operable actuating means, to compress said coil spring means for energization thereof, said slidable means being adapted to release said hammer means when brought into contact with the sloping-cam surfaces of said frame to permit said hammer means to be driven by said coil spring means to thereby impart an impact to said piezoelectric element to cause a spark, across said spark gap for ignition of fuel, said ignition mechanism unit also having a valve opening lever pivotally fixed to said frame and operatively connected to said manually operable actuating means so that fuel is supplied to said burner synchronously with operation of said manually operable actuating means.

2. A dismountable piezoelectric liquefied gas fueled lighter as claimed in claim 1, wherein said hammer means includes a laterally rearwardly projecting pin adapted to be engaged by a cut-out portion formed at the lower portion of said slidable means, said slidable means being normally urged to contact the rear edges of the side walls of said U-shaped frame by spring means and having at its upper portion a pair of cars laterally extending in opposite directions and slidably engaged in vertical guide slits formed in the side walls of said frame, and also having at its lower end roller means adapted to roll on the rear edges of said side walls for facilitating sliding movement of said slidable means on said rear edges and also for facilitating releasing of engagement between said hammer means and said slidable means.

3. A dismountable piezoelectric liquefied gas fueled lighter as claimed in claim 1, wherein said ignition mechanism unit is connected to said fuel reservoir unit in such a way that the side walls of said U-shaped frame are removably secured to a bracket, provided on a side wall of said fuel reservoir, by screw means, and the bottom of said frame is removably secured to the bottom wall of said reservoir by screw means.

4. A dismountable piezoelectric liquefied gas fueled lighter as claimed in claim 1, wherein said casing is of a rectangular shape and has in its upper wall an outlet opening for discharging a flame and in its rear wall a vertically elongated aperture along which said manually operable actuating means is adapted to slide, said actuating means being of a substantially triangular shape in side view and mounted on the outer side of the rear wall of said casing.

5. A dismountable piezoelectric liquefied gas fueled lighter as claimed in claim 1, wherein said valve opening lever is provided with a forked end portion engaging the burner of said burner-valve assembly and also with a pair of curved legs extending rearwardly and obliquely downwardly and adapted to be engaged by a portion of said slidable means to thereby open the valve of said burnervalve assembly.

References Cited UNITED STATES PATENTS 3,200,295 8/1965 Owens et al 431-131 3,295,024 12/1966 Newman 431-132 X 3,387,912 6/1968 Goto 431- 3,425,783 2/ 1969 Goto 431-255 EDWARD J. MICHAEL, Primary Examiner US. Cl. X.R. 431-255