US3665859A - Priming device - Google Patents

Abstract

A priming device inside of a chamber includes a flat ring, in which is disposed a shallow cup that is encircled by an integral flange overlapping one side of the ring, to which one side of the flange is secured. The bottom of the cup has a hole through it and the cup contains pyrotechnic material. The opposite side of the flange is secured to a thin metal wall of the chamber. The material in the cup is detonated by striking the thin wall to bend it into the cup so that it will press against the pyrotechnic material.

Description

Unite States fie t [151 3,665,859 Caples 1 30, 1972 541 PRIMING DEVICE 733,638 5/1903 Gardner.... l02/86.5 [72] lnvemor: Allen s. Capks, Baltimore, M d 3,124,075 3/1964 Eldh et a] 102/865 [73] Assignee: Catalyst Research Corporation, Baltimore, Primary Examiner-Samuel W. Engle M Attorney-Brown, Murray, Flick & Peckham 22 F'] d: Ma 25 1970 l 1 y 57 ABSTRACT 21 A 1. No.: 40 156 1 pp A priming device inside of a chamber includes a flat ring, in which is disposed a shallow cup that is encircled by an integral [52] US. Cl. l02/45, 102/70 R, 102/865 flange overlapping one Side f h ring m which one side f [5 l] Int. Cl. ..F42C 19/10 the flange is Secured The bottom of the cup has a h [58] Field of Search 102/46 45 through it and the cup contains pyrotechnic material. The opposite side of the flange is secured to a thin metal wall of the [56] References Cned chamber. The material in the cup is detonated by striking the UNITED STATES PATENTS thin wall to bend it into the cup so that it will press against the pyrotechnic material. 1,313,801 8/1919 Doran ..102/86.5 3,186,341 6/1965 Bjorklund ..l02/86.5 4 Claims, 2 Drawing Figures Patented May 30, 1972 lNVE/VTOR. ALLEN 5. 01, 4 5

Fig.2

PRIMING DEVICE It is an object of this invention to provide a priming device that can have a much smaller volume than priming devices usually used for firing pyrotechnic compositions in a chamber. Other objects are to provide a priming device that is completely enclosed and sealed, which does not have to be struck in an exact spot in order to detonate it, which is much simpler than conventional primers with their holders, and which has fewer parts and requires no particular care or skill in mounting it in position.

The preferred embodiment of the invention is illustrated in the accompanying drawings, in which FIG. 1 is an end view, partly broken away, of a chamber containing the priming device; and

FIG. 2 is a fragmentary view, partly in section on the line "-11 of FIG. 1.

Referring to the drawings, a sealed chamber 1 containing a pyrotechnic composition 2 that is to be fired has a relatively thin metal wall. This may be an outside wall of the chamber or an inside partition wall. In the drawing, it is shown as being the end wall 3 of the chamber that is in the form of a can. Inside the chamber or can there is a priming device that is surrounded by composition 2. The principal portion of the device is a shallow cup 4 encircled by a flat integral radial flange 5. The cup fits in a flat ring 6, like a washer, with the flange overlapping one side of the ring and secured to it by an adhesive or by spot welds 7 or the like. The opposite side of the flange is secured in the same or similar manner, such as by an adhesive 8, to the inner surface of the thin metal wall of the can. This wall therefore closes the cup. The cup contains an impact sensitive pyrotechnic material 9 of any well known type, which preferably is in the form of a coating on the bottom of the cup. It is spaced from the thin end wall of the can. The bottom of the cup is provided with a central hole 10 through it.

When the thin wall of the can is struck by an instrument that will cause it to be bent into the cup and strike the pyrotechnic material 9 therein, the latter will be detonated and the fire will pass through hole 10 in the cup to fire the pyrotechnic composition 2 in the can around the priming device.

The washer or ring 6 adds rigidity to the device for handling and it protects the cup from compressive forces due to the pyrotechnic material 2 consolidated or pressed tightly against the outside of the device within the can. This ring, along with the space between the can wall and the pyrotechnic coating in the cup, isolates the coating from premature or inadvertent firing.

It will be seen that this priming device is very simple and requires but little space. It has only two parts and requires no particular care or skill to mount it in place. The entire device is sealed inside the can so that it cannot be affected by the out side atmosphere. Because the pyrotechnic coating within the cup is spread over a relatively large area, a strike against it by the wall of the can anywhere within that area will fire the primer, unlike conventional primers which require a strike very nearly in the exact center. If a conventional primer holder is mounted on a thin wall, the relatively large diameter of the holder tends to diffuse part of the striking force into elastic deflection of the wall in a direction and manner detrimental to firing the primer. On the other hand, with the arrangement disclosed herein, the applied stress is concentrated in the small firing pin area so that more plastic than elastic deformation occurs.

According to the provisions of the patent statutes, I have explained the principle of my invention and have illustrated and described what I now consider to represent its best embodiment. However, I desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

I claim:

1. In combination with a thin metal wall of a chamber, a priming device in the chamber comprising a flat ring, a shallow cup disposed in said ring and encircled by an integral flange overlapping one side of the ring, means securing the ring to the adioining side of said flange, the bottom of the cup having a ho e through it, a coating of impact sensitive pyrotechnic material on the inner surface of the bottom of the cup, and means securing the opposite side of said flange to said wall to close the cup, said wall being deformable into the cup against said material to detonate it.

2. In the combination recited in claim 1, said chamber being sealed and filled with a pyrotechnic composition to be fired by said priming device.

3. In the combination recited in claim 1, the combined thickness of the ring and flange being at least as great as the height of the cup.

4. In the combination recited in claim I, said first-mentioned securing means being disposed between said ring and flange, and said last-mentioned securing means being disposed between said flange and wall.

Claims (4)

1. In combination with a thin metal wall of a chamber, a priming device in the chamber comprising a flat ring, a shallow cup disposed in said ring and encircled by an integral flange overlapping one side of the ring, means securing the ring to the adjoining side of said flange, the bottom of the cup having a hole through it, a coating of impact sensitive pyrotechnic material on the inner surface of the bottom of the cup, and means securing the opposite side of said flange to said wall to close the cup, said wall being deformable into the cup against said material to detonate it.

2. In the combination recited in claim 1, said chamber being sealed and filled with a pyrotechnic composition to be fired by said priming device.

3. In the combination recited in claim 1, the combined thickness of the ring and flange being at least as great as the height of the cup.

4. In the combination recited in claim 1, said first-mentioned securing means being disposed between said ring and flange, and said last-mentioned securing means being disposed between said flange and wall.

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