US3411858A

US3411858A - Combustion devices

Info

Publication number: US3411858A
Application number: US578837A
Authority: US
Inventors: Fuller Douglas Somerville
Original assignee: Individual
Current assignee: Individual
Priority date: 1965-09-14
Filing date: 1966-09-12
Publication date: 1968-11-19
Anticipated expiration: 1985-11-19
Also published as: AT271964B; CH437884A; NL6612871A; DE1529150A1; GB1155711A; BR6682802D0

Description

D. S. FULLER Nov. 19, 1968 COMBUSTION DEVICES 2 Sheets-Sheet 1 Filed Sept. 12, 1966 FIG. 3

4 e 5: 3 W zgfi llak. Iv 2 $6 A g m 3 1,1 l l FIG.

INVENTOR Douglas Somerville Fuller ATTORNEYS Nov. 19, 1968 D. s. FULLER COMBUSTION DEVICES 2 Sheets-Sheet Filed Sept. 12, 1966 FIG. 8

FIG. 5

FIG. 7

FIG. 6

iNVENTOR Douglas Somerville Fuller ATTQRNEYS United States Patent COMBUSTION DEVICES Douglas Somerville Fuller, Burrows, Long Reach, Ockham, Surrey, England Filed Sept. 12, 1966, Ser. No. 578,837 Claims priority, application Great Britain, Sept. 14, 1965,

10 Claims. (Cl. 431267) This invention relates to combustion devices, and particularly to combusion devices for domestic use such as heat producing devices, light producing devices, gas Wands, flame welding torches, and portable lighting devices such as cigarette lighters, in which the ignition of fuel escaping from a burner is effected by the spontaneous combustion of a pyrophoric substance brought into contact with air.

Since suitable pyrophoric substances are generally extremely expensive, it is important that only a very small and accurately metered quantity of the pyrophoric substance shall be released to the ambient atmosphere when it is desired to effect combustion of fuel supplied from a reservoir thereof to a burner, and it is an object of this invention to provide an improved combustion device having manually operable means which provides the desired accurate metering of the pyrophoric substance for ignition of the fuel at the burner.

According to the present invention, the improved device includes a reservoir of pyrophoric substance and metering means for delivering measured quantities of the pyrophoric substance to the ambient atmosphere adjacent a fuel burner, the metering means comprising an elongated member contained within the reservoir and adapted to be withdrawn step by step therefrom through a snugly fitting sealing means, the elongated member being so formed that at each step a measured volume of pyrophoric substance entrained by the member is released to the ambient atmosphere adjacent the burner.

These and other novel features of the invention will be more readily understood from the following description taken in conjunction with the accompanying drawing in which FIG. 1 is a schematic side elevation of the metering device of the invention;

FIG. 2 is a side elevation of the self-sealing end portion of the elongated member shown in FIG. 1;

FIG. 3 is a side elevation, partly in section, of a cigarette lighter embodying the invention;

FIG. 4 is a partial end view, partly broken away, of the take-up mechanism shown in FIG. 3;

FIG. 5' is a side elevation, partly in section, of another modification of a cigarette lighter embodying the invention;

FIGS. 6 and 7 show alternative modifications of the elongated member which carries the pyrophoric igniter substance; and

FIG. 8 is a side elevation, partly in section, of an additional embodiment of the invention in the form of a gas wand using a modification of elongated member shown in FIG. 5.

The metering device for pyrophoric igniter substance shown in FIG. 1 comprises an elongated member A in the form of a chain of alternative segments of wire 10 and uniformly spaced bead-like bodies 11. The wire can be integral with the bead-like bodies mounted on the wire at spaced intervals or the wire can be of short individual segments connected at each end of the bead-like bodies as in a conventional key chain construction. The elongated member A is stored in a reservoir compartment 12 containing a pyrophoric substance 13 having an outlet neck 14 formed at its top end. The neck 14 is provided interiorly with an elongated seal member 15 having a central bore 16 whose diameter is such as to provide a close fit 3,411,858 Patented Nov. 19, 1968 for the bead-like bodies 11 as they pass through this bore. The seal member is advantageously formed of resilient material such as rubber or plastic sponge, but it will be appreciated that it can be formed of a non-stick material such as polytetrafiuoethylene polymer. The length of the seal bore 16 is greater than the distance spanned by two successive bead-like bodies so that there is always a pair of these bodies within the bore. The space between the bodies 11 within the seal bore 16 forms a trap for pyrophoric substance rising or carried up from the reservoir.

Accordingly, the spacing between the bead-like bodies 11 within the seal bore 16 determines the amount of pyrophoric substance which is made available by withdrawing one unit of the elongated member from the top of the seal opening. The elongated member is drawn stepwise through the seal bore by any suitable take-up device such as a staror cog wheel 17. If desired, a shearing blade 18 can be provided to cut off used units of the elongated member A, and the inner end of the elongated member can be provided advantageously with a selfsealing plug 19, as shown in FIG. 2, which will close the inner end of the seal bore 16 when the end of the elongated member reaches this point.

The pyrophoric substance charged to the reservoir compartment 12 may be either normally gaseous or normally liquid, such, for example, as aluminum borohydride, trimethyl aluminum, boranes such as diborane through pentaborane, silanes such as monodiand tn'silane, dimethyl zinc, carbonyl nickel, dimethyl boron, and the like.

The embodiment of the igniter device of the invention in a cigarette lighter is shown in FIG. 3. The lighter comprises a conventional outer case 20 having an inner case 21. One portion of the inner case is provided with a conventional compartment 22 which serves as a reservoir for lighter fuel such as butane and with a conventional burner 23 extending upwardly above the case. Adjacent the fuel reservoir there is positioned another compartment formed by enclosing walls 24 to define a reservoir for the pyrophoric substance, and this compartment is preferably but not necessarily formed as a removable cartridge within the inner case 21. The remainder of the inner case is advantageously formed as a receptacle 25 for spent elongated member from which the pyrophoric substance has been eliminated by its spontaneous combustion.

At the top of one sidewall 24 of the pyrophoric substance compartment a neck 14a is formed by an inverted collar. The interior of the neck is provided with a seal 15a of resilient sponge rubber having a central longitudinal bore 16 and a communicating side bore 26 aligned with an igniter opening 27 in the compartment side wall 24 adjacent the upper end of the burner 23. Thus, as one unit length of the elongated member A is drawn through the seal bore 16 to the position of the side bore 26, the pyrophoric substance entrapped by this unit is exposed to the ambient atmosphere and ignites spontaneously in the opening 27.

Movement of the elongated member A through the seal bore 16 is provided by a take-up device mounted on a bracket 28 on the top wall of the pyrophoric substance compartment. The bracket 28 carries a horizontal shaft 29 on which, as shown more clearly in FIG. 4, is mounted a cog wheel 30 flanked by larger diameter ratchet wheels 31. The spacing of the cogs on the wheel 30 corresponds to the spacing between successive bead-like bodies 11 on the elongated member A, and the ratchet wheels 31 serve as flanges to hold the elongated member on the cog wheel. Rotation of the ratchet wheels 31 is effected by a pawl 32 carried by a finger piece 33. The inboard end of the finger piece is pivoted on the wheel shaft 29 and its outboard end engages a compression spring 34. Outward and downward movement of the finger piece 33 causes the pawl 32 to rotate the ratchet wheels 31, and this movement is advantageously used to cut off spent elongated member by the action of a pivoted cutter blade 35 secured to the underside of the finger piece. The portion of the elongated member cut off in this manner is free to fall through an opening 36 in the top wall of the compartment 25. In order to prevent rattling of cut off portions of the elongated member within the compartment 25, the walls of this compartment are advantageously lined with sponge rubber 37 or the like.

Rotation of the ratchet wheels 31 by movement of the finger piece 33 is also used to open a nozzle 38 on the top of the burner 23 by keying a forked arm 39 to the wheel shaft 29. Thus, movement of the finger piece 33 causes (a) one-step rotation of the cog wheel 30; (b) upward movement of one unit of the elongated member A through the seal bore 16; and opening of the burner nozzle 38. The flame from the burner projects upwardly through an opening 40 in a flame guard 41 which provides a partial cover for the lighter.

In the cigarette lighter embodiment of the invention shown in FIG. 5, the inner case 21 is provided with a conventional fuel chamber extending across the full width of its lower portion with the burner 23 mounted in the same position as in FIG. 3. To the side of the burner and above the fuel chamber, a reservoir compartment for the pyrophoric substance is formed by walls 24a. The seal in this embodiment, however, is constructed so as to permit use of a loop of the elongated member A which extends into the reservoir compartment and over and around the ratcheted take-up cog wheel 30. The seal comprises an innermost U-shaped metal shell 42 having an inner lining 43 of resilient rubber-like material or non-stick material. Spaced from the lining 43 by a distance no greater than the diameter of the bead-like bodies 11 is a second liner 44, of the same material as the other liner 43, which is supported by a second metal shell or backing 45. The second liner-

shell assembly

44, 45 is open at its lower end so that the loop of the elongated member A within its reservoir compartment passes out of the seal bore 16 and into the supply of pyrophoric substance therein. The take-up wheel 30 is provided with an operating fingerpiece 33 as in FIG. 3. However, no cutter is required in this embodiment of the invention because of the use of an endless loop of the elongated member A.

In an alternative embodiment of the elongated member of the invention, the bead-like bodies 11 may be formed so as to entrain the desired quantity of pyrophoric substance. For example, the bodies can be formed of porous material, such for example as diatomaceous earth, clay, or the like, with or without a hollow center, or as hollow shells of an impervious material, such as metal or plastic, with one or more openings therein, or of a material that is readily wetted by a liquid pyrophoric substance, the actual construction being determined to some extent by whether the pyrophoric substance is used in the liquid or in the vapor phase. In still another alternative embodiment of the invention, the elongated member A, as shown in FIG. 6, is either round or flat and is formed with a plurality of cavities, for example by forming it with a plurality of spaced transverse bores 46. In such case the elongated member is advantageously formed, for example, of nylon or other flexible plastic material. The elongated member A can also be formed of strip metal or plastic with the aforementioned transverse bores 46, or it can be formed of conventional wire 47 which is kinked or crinked, as shown in FIG. 7, the space between each pair of kinks serving to trap the desired amount of the pyrophoric substance within the seal 15.

In the embodiments of the invention which use an elongated member A in the form of a wire having bead-like bodies 11 secured thereon such as is shown in FIGS. 1 through 4, these bodies themselves may be made of a combustible material such as carbon, cellulose, wax, or the like, so that they are set alight by the ignition of the pyrophoric substance as they leave the reservoir compartment. In such modification, no separate source of fuel or fuel burner is required because the elongated member itself forms the burner and the supply of combustible bead-like bodies within its reservoir serves as a reservoir of the fuel.

It will be readily understood that all modifications of the elongated member A are used with a reservoir discharge seal which provides a tight enclosure about a sufficient length of the elongated member to serve as a trap for a discrete amount of the pyrophoric substance. In the case of a seal of resilient material such as sponge rubber, the bore 16 is preferably smaller than the diameter or cross-section of the elongated member A to provide this tight fit. In the case of a seal provided by a layer of polytetrafluoethylene polymer or similar non-stick material, the bore 16 can be the same dimension as the crosssection of the elongated member A so as to provide a free-moving but tight fit between the seal bore and the elongated member.

In the embodiment of the invention shown in FIG. 8, the burner and its supply of fuel comprises a conventional gas wand 48 the upper end of which is provided with a burner nozzle 23 and the lower end of which is connected by a flexible hose 49 to a manufactured or natural gas supply. The igniter element for the wand and the wand itself are mounted on a base plate 50 which carries the wheel shaft 29. As in previously described embodiments, a take-up wheel 30, advantageously in the form of a cog wheel, and a ratchet wheel 31 are rotatably mounted on the shaft 29 along with a finger piece 33 carrying the ratchet pawl 32.

The elongated member A used in the device of FIG. 8 is the modification shown in FIG. 6 and comprises a closed loop of strip material provided with spaced transverse bores 46 in the form of slots. The loop passes upwardly through an inverted U-shaped seal similar to that shown in FIG. 5 except that it is not cut-away at the bend of the U. One of the legs of the U is elongated and forms at its lower end a sidewall of a reservoir compartment 51 for the pyrophoric substance 13. The elongated member A passing through the bore of the seal between the inner seal layers 43 and 44 passes an opening in the side wall communicating with the reservoir and picks up a discrete amount of the pyrophoric substance in each of its slots 46. As the movement of the elongated member is effected upwardly through the bore of the seal, it entraps these discrete amounts of the pyrophoric substance and carries each to an opening 52 near the top of the seal adjacent the burner nozzle. The return portion of the band of elongated member passes through the bend of the U- shaped seal and back to the take-up wheel 30. Thus, each movement of the finger piece 33 advances a unit (slot) of the elongated member to the seal opening 52 where exposure of the pyrophoric substance to the ambient atmosphere causes its ignition close to the burner nozzle 23.

In all embodiments of the invention it will be seen that the elongated member is such and is so arranged that by its step-wise motion it carries a discrete amount of phyrophoric igniter substance to the ambient atmosphere adjacent a burner where spontaneous ignition of the pyrophoric substance causes ignition of fuel at the burner.

I claim:

1. In a combustion device wherein ignition of fuel delivered to a burner is effected by spontaneous combustion of a pyrophoric substance brought into contact with the ambient atmosphere adjacent the burner, the device being provided with a fuel reservoir, a fuel burner, a storage reservoir for the pyrophoric substance, and metering means for delivering a measured quantity of the pyrophoric substance to the atmosphere adjacent the burner, the improvement which comprises an elongated storage seal communicating with the pyrophoric substance reservoir, metering means in the form of an elongated member stored within the pyrophoric substance reservoir and extending out of said reservoir through a longitudinal opening in the seal, withdrawing means for withdrawing stepwise through the seal and into close proximity to the burner a discrete length of the elongated member, each discrete length of the elongated member entrapping within the seal a measured amount of the pyrophoric substance available for spontaneous ignition when exposed to the ambient atmosphere adjacent the burner by withdrawal of said discrete length of the elongated member out of the seal.

2. A combustion device according to claim 1 in which the elongated member is in the form of spaced bead-like bodies interconnected by wire, the distance between each pair of bead-like bodies being less than the length of the longitudinal opening in the seal.

3. A combustion device according to claim 1 in which the elongated member is in the form of spaced bead-like bodies interconnected by wire, each of the bead-like bodies being capable of holding a discrete amount of the pyrophoric substance.

4. A combustion device according to claim 1 in which the elongated member is of substantially uniform size throughout its length and is provided at spaced intervals with transverse bores each adapted to entrap a discrete amount of the pyrophoric substance.

5. A combustion device according to claim 1 in which the elongated member consists essentially of a length of kinked wire adapted to entrap between its kinks within the seal a discrete amount of the pyrophoric substance.

6. A combustion device according to claim 1 in which the elongated member is in the form of spaced bead-like bodies of combustible material serving as the fuel for the device.

7. A combustion device according to claim 1 in which the seal is of resilient material and the longitudinal opening in the seal has cross-sectional dimensions smaller than those of the elongated member.

8. A combustion device according to claim 1 in which the longitudinal opening in the seal is surfaced with a non-stick material and the cross-sectional dimensions of the openings are substantially the same as those of the elongated member.

9. A combustion device according to claim 1 in which the withdrawing means is provided with a cutter to sever the spent portion of the elongated member discharged from the withdrawing means.

10. A combustion device according to claim 1 in which the elongated member is in the form of a closed loop communicating between the storage reservoir for the pyrophoric substance and the withdrawing means through a pair of similar elongated seals communicating with the storage reservoir.

References Cited UNITED STATES PATENTS 3,085,411 4/1963 Daugherty 67--7 EDWARD J. MICHAEL, Primary Examiner.

Claims

1. IN A COMBUSTION DEVICE WHEREIN IGNITION OF FUEL DELIVERED TO A BURNER IS EFFECTED BY SPONTANEOUS COMBUSTION OF A PYROPHORIC SUBSTANCE BROUGHT INTO CONTACT WITH THE AMBIENT ATMOSPHERE ADJACENT THE BURNER, THE DEVICE BEING PROVIDED WITH A FUEL RESERVOIR, A FUEL BURNER, A STORAGE RESERVOIR FOR THE PYROPHORIC SUBSTANCE, AND METERING MEANS FOR DELIVERING A MEASURED QUANTITY OF THE PYROPHORIC SUBSTANCE TO THE ATMOSPHERE ADJACENT THE BURNER, THE IMPROVEMENT WHICH COMPRISES AN ELONGATED STORAGE SEAL COMMUNICATING WITH THE PYROPHORIC SUBSTANCE RESERVOIR, METERING MEANS IN THE FORM OF AN ELON-