US3508853A

US3508853A - Igniter

Info

Publication number: US3508853A
Application number: US772327A
Authority: US
Inventors: James R Thurston; Henry J Roberts; Christopher W Bolieau; Edward E Mccullough
Original assignee: Thiokol Corp
Current assignee: ATK Launch Systems LLC
Priority date: 1968-10-31
Filing date: 1968-10-31
Publication date: 1970-04-28
Anticipated expiration: 1987-04-28

Description

J. R. THURSTON ET L IGNITER April 28, 1970 Filed Oct. 31, 1968 2 Sheets-Sheet 1 JAMES R. THURSTO/V HENRY J. ROBERT 6 CHRISTOPHER W. BOL/EAU EDWARD E. McCULLOUGH INVENTORS THE/l A 6 EN April 28, 1970 u s'ro ET AL 3,508,853

IGNITER 2 Sheets-Sheet 2 Filed Oct. 31, 1968 Fig.5

JAMES R. THURSTO/V HENRY J. ROBERTS CHRISTOPHER W BOL/EAU EDWARD E. M6 CULLOUGH INVENTORS BY $7 THE/E J United States Patent US. Cl. 431270 10 Claims ABSTRACT OF THE DISCLOSURE An igniter for flares, smoke pots, canned heat and other solid or semi-solid combustible materials contained in a sealed tear top can in which the igniter is completely attached to the underside of the can top, is spring loaded to assure positive high friction between a scratcher and a match material, and is operated simply by opening the tear top of the can.

The present invention relates to ignition devices and, more particularly, to those which are intended to ignite a combustible material contained in a can such as is the case with a flare, canned heat, smoke pots, or the like. It also relates to igniters which are provided along with the can rather than as a separate entity.

Among the problems associated with flares, canned heat, smoke pots and the like are those of keeping the combustible material sealed from moisture and air during storage, which can cause the device to become inoperative because of oxidation and corrosion of the parts or due to an excess of water in the combustible material. Since these devices ordinarily spend long periods in storage prior to their use and yet must remain in good operating condition if they are to perform their functions satisafctorily, they must be very effectively sealed. One of the most effective ways of accomplishing this is the inclusion of the entire device inside a hermetically sealed container which is opened only at the time of use. It has been found by the present inventors that a metal can having a top which is rolled or crimped in place about its periphery and has a tear out tab portion embossed in its top with an attached pull ring is well suited for this purpose.

Another problem however, which presents itself in the use of such cans is how to keep all of the various igniter parts in proper position and relationship to one another during assembly and to insure that they do not change positions later during storage with resultant unexpected ignition or inoperativeness. In the present invention a solution to all of these problems is presented in the form of an ignition device which is wholly attached to the cover and therefore all of the, igniter parts are maintained in proper relationship to one another at all times.

Another important problem which is solved by the present invention is that of providing a positive, tamper proof and safe ignition device which will operate automatically upon opening of the can without the need for a hand held match or other flame which is not as safe and often is inconvenient. In the present invention, the igniter is operated by the upward pull of the tear strip as it is removed. This device is at once a positive, safe, automatic and effective igniter which is completely tamperproof upon the sealing of the top to the can.

It is, accordingly, an object of the present invention ice to provide an igniter for the combustible portion of a potted combustible such as a flare, smoke pot, canned heat and the like in which the igniter is sealed from moisture and corrosive atmospheres until its time of use.

It is another object of the present invention to providean igniter of the foregoing type which is at once effective, safe, tamperproof, and completely automatic as the tear out tab of the can cover is removed.

In the drawings:

FIGURE 1 is a cutaway cross sectional elevation of one embodiment of the invention as applied to a flare or smoke pot;

FIGURE 2 is a cutaway cross sectional view of another arrangement of the invention as applied to a flare or smoke pot;

FIGURE 3 is a cross sectional view of another arrangement of the invention as applied to a container of canned heat with the view taken transversely of the tear out strip;

FIGURE 4 is perspective view of the cover in inverted position and showing the igniter of FIGURE 1;

FIGURE 5 is an exterior view of the assembled can unit showing the tear out portion of the cover and the pull ring.

In a preferred embodiment of the invention, and with reference to FIGURE 1 of the drawings, a container 10 preferably of the aluminum can type is partially filled with a combustible light-producing compound 11. This compound is intended to be one of the common flare mixes used for this purpose and should be of the type which is capable of producing a colored light if that is desired or the compound could be a smoke producing material or one of the gelled combustibles commonly know as canned heat. At the top of the container 10, is a cover 12 which is rolled or crimped at its periphery into the upper periphery of the container 10 to form a hermetic seal. The cover 12 has a tear out tab portion or strip 13 including a pull ring 14, the tear out tab portion being integral with the cover but embossed in it (see particularly FIGURE 5) and with the pull ring 14 on the exterior of the cover and riveted to tear out strip by rivet 15.

Attached to the underside of cover 12 by rivets, welding or the like, is match support and guide 16 which is preferably of formed sheet aluminum. Between it and cover .12 are scratcher 17 and match composition or match 18 which must be on the same side of scratcher 17 as match 18. Scratcher 17 extends beyond support 16 and is a strip of spring metal attached at one end to tear out tab 13 by rivet 15. It is coated with abrasive 17a or otherwise roughened at its unattached end start ing just beyond the match composition and extending to its end. In other words, that portion of scratcher 17 which is directly under or otherwise touches the match is not coated with the abrasive material in order that movement of scratcher 17 due to jarring or slight deformation of cover 112 during shipment or normal handling will not cause the match composition to ignite accidentally by friction between the match and scratcher. It should be noted that scratcher 17 is twisted out of its plane as shown in the drawing in order to afford a spring loading effect of the scratcher upon the match composition as it is withdrawn through guide 16 in order that considerable friction will be created and positive ignition of the match 18- from the heat generated will occur. Also, it will be seen in FIGURE 1 that scratcher 17 is looped or folded back upon itself from its point of attachment to the support 16 in order to increase its length for the purpose of delaying the pull of its abrasive en'd slightly and thus to provide the operator a little more time to open the can fully before ignition occurs.

In operation, the ring 14 is lifted and then pulled in the direction of the tear out tab 13 thus tearing it out along the embossed line and leaving a cover remainder 20, with an opening in it. As this action occurs, scratcher 17 is, after a slight delay as its looped length or slack is taken up, automatically pulled under match support and guide 16 straightening out the twist of scratcher 17 as the scratcher passes through the narrow space between the guide 16 and cover 12, and the match 18 and the abrasive portion of the scratcher rubs briskly across the match composition 18 and under the spring urging of scratcher 17 as it untwists causes friction heat which ignites the match 18. The ignition of the match composition causes sufiicient heat to raise the temperature of the surface of the flare composition to its combustion point and it then burns creating a bright light or producing smoke, or both, or just heat as the case may be.

Since scratcher 17 is a flat metal member and has sufficient thickness to prevent tearing, buckling, or deformation when pulled under guide 16, it cannot kink or snag or otherwise become caught or wedged but will always pull straight through.

In another configuration of the same invention as shown in FIGURE 2, a flare, smoke producing compound or the like 11 is contained in can 10, and a cover 12, tear out tab 13 and pull ring 14 are provided as previously. The igniter, however, comprises a support and guide member 21 attached fixedly to cover 12 but only to the portion of the cover remaining after removal of the tear out tab and not to the tear out tab 13 itself. Scratcher 22, however, is attached only to tear out tab 13 and will therefore move with it with respect to support 21. Between scratcher 22 and support 21 and supported by support 21, is match or match composition 23 which is of the same composition used in FIGURE 1. Scratcher 22 is of spring metal and its extremities which extend downward from support 21 are bent away from one another in the manner shown in FIGURE 2 so that a definite spring effect will be brought about upon the match 23 urging the scratcher 22 very definitely against it as the scratcher is withdrawn when the tear strip 13 is removed. The lower or bent out ends of scratcher 22 are roughened or coated with abrasive material at 24 but the roughened portion does not reach the match 23 until the scratcher 22 has moved upward a small distance thus preventing any possibility of accidental ignition due to handling, jarring or the like and providing a slight delay in the ignition which again allows the operator more time to open the can before ignition occurs.

In operation, the ring 14 is pulled as previously described tearing out tear out tab 13. This action pulls scratcher 22 upward through support and guide 21 and over match 23 thus compressing the springy, roughened ends of scratcher 22 and causing them to pass across match 23 with a firm and positive spring pressure to produce friction heat and thus to ignite the match composition. The heat from the burning match 23 then ignites the flare (or other) composition.

In FIGURE 3 is shown another configuration of the present invention which is similar to that shown in FIG- URE 2 except that the match supports 25 and 25a are separate, are located laterally of tear out tab 13, and neither the abrasive nor other portions of scratcher 26 are in initial contact with the

matches

27 and 27a. As will be seen from FIGURE 3, scratcher 26 is lifted upward when tear out strip 13 is removed in the usual manner. As it moves upward, its

abrasive ends

28, 28a are drawn against and then across

matches

27 and 27a, the spring action of scratches 26 as it bends causing spring pressure between it and the matches thus insuring considerable friction. This friction then ignites the

matches

27 and 27a and the flare (or other) composition becomes ignited therefrom.

In all three of the foregoing configurations, additional delay means (not shown) can be used if desired, in the form of slow burning materials which burn before the main combustible becomes ignited but this depends on the rate of burning of the main combustible and ordinarily would not be necessary.

It is intended that the can, cover and as many other of the metal parts as possible (including the striker if made to retain spring-like qualities), be made of aluminum so that they will be consumed by the fire. It is particularly desirable that the cover be made of aluminum or the like so that it will be readily consumed and Will open the top of the can completely.

It is important to note that all of the igniter components of all configurations of the present invention are fastened directly to the under side of the cover which makes it possible to assemble the igniter entirely separately from the can after which the cover is placed on the can and their respective peripheries are crimped together to form a hermetic seal. The entire device then appears as is shown in FIGURE 5 and is ready for instant use.

It is to be understood that the form of my invention herewith shown and described is to be taken as a preferred example of the same and that various changes in the shape, size and arrangement of parts may be resorted to without departure from the spirit of the invention or the scope of the subjoined claims.

What is claimed:

1. An igniter for a substantially solid combustible contained in a sealed can having a cover including a tear out tab portion com-prising, in combination, a spring metal scratcher attached to said cover and having an abrasive portion substantially at its unattached end, a match, support means supporting said match in close proximity to the scratcher and attached to said cover, said scratcher and said support means being separately attached one to the tear out tab portion of the cover and the other to that portion of the cover apart from the tear out tab portion, means guiding the scratcher abrasive portion over the match in contact with it, and said scratcher being so formed that its abrasive portion will contact and rub across said match with positive spring pressure as the tear out tab is removed and the scratcher is pulled, whereby the match becomes ignited from the friction heat generated by this action and the combustible contained in the can is thereafter ignited by the heat of combustion of the match.

2. The invention set forth in claim 1 with the scratcherattached to the tear out tab portion of the cover.

3. The invention set forth in claim 1 with the support means attached to the portion of the cover apart from the tear out tab portion.

4. The invention set forth in claim 1 with the scratcher bent about its longitudinal axis to provide the spring action.

5. The invention set forth in claim 1 with the scratcher being attached in its middle to the tear out tab and bent downward adjacent its free ends and extended over the matches so that the abrasive portion of the scratcher will be dragged over the match with spring action.

6. The invention set forth in claim 1 with the scratcher U-shaped with its legs bent outward slightly and the match located on each side of the scratcher and adapted to be rubbed by the abrasive portions of the scratcher as they are pulled upward, whereby the outwardly bent legs provide a spring action as they are compressed between the matches.

7. The invention set forth in claim 1 with the scratcher bent transversely between its abrasive portion and the match and the bend being in the direction of the match.

8. The invention set forth in claim 1 with the scratcher being a flat strip having an abrasive portion at its unattached end, guide and support means adapted to direct the flat strip in one plane and to support a match in the path of the abrasive portion of the strip, and a twist of less than 90 degrees in the scratcher between its References Cited abrasive end and the guide means.

9. The invention set forth in claim 1 with the abrasive UNITED STATES PATENTS portion of the scratcher and the match separated ex- 2,237,523 4/1941 431 269 cept when the tear out tab is being removed. 5 2,584,040 1/1952 Naramlclc 10. The invention set forth in claim 8 with the scratcher 2,896,607 7/1959 Ede! 126-262 folded back upon itself at its attached end to increase its length, whereby ignition is delayed to the extent of EDWARD G'FAVORS Primary Exammer the time it takes to take up the extra length before the US. Cl. X.R. scratcher is pulled. 10 44-39; 126262