US1805214A - Delay powder - Google Patents

Description

Patented May 12, 1931- UNITED- STATES" 'enoaen c. HALE, or Down, mm mm DELAY rowmm Ho Drawing.

Application filed January 8, 1925. Serial No. 462.

(GRANTED UNDER THE ACT OF MARCH 3, 1883, AS AMENDED APRIL 30, 1928; 870 0. G. 757) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.

The subject of this invention is a delay powder intended for use primarily in fuses.-

The powders heretofore used for delay powder trains, one of the principal uses of such powders being in time train fuses, gave uniformly good results until the advent of aircraft into warfare and the consequent necessity of propelling projectiles into the upper strata of the atmosphere where the air is more rarefied and the atmospheric pressure consequently reduced.

Under these circumstances it is found that the fuses give very erratic functioning re-.

tus which is partially evacuated. In a'16" vacuum the burning time of the fuse at full setting is approximately ll seconds slower than under atmospheric pressure. Under these conditions some of the fuses fail to burn through completely. Thus it seems that it has practically been proven that low pressure is responsible for the erratic action of the fuses in firing tests.

Efforts have been made to overcome this difficulty by altering the composition of black powder in such a way as to obtain powders which will give a higher temperature upon 40 burning and greater ease of ignition. While a some improvement was effected in this manner no powder was obtained which would burn uniformly under reduced'pressure.

By departing entirely from the typeof powders just referred to, it has been mind that the difliculty can be overcome. To obtain this result it is proposed to provide a powder composed of substances one or more of which will decompose, when decomposition is once started, and others of which will combine with the gases evolved on decomposition, the chemical reactions taking place evolving suflicient heat to insure a continuation of the reactions until the train is completely converted. The result of these chemical reactions is the production of solids rather than gases.

Powders combined in this way are found to burn uniformly even in rarefied air and accuracy of the setting of a time fuse having such a powder train is greatly enhanced.

A powder of this character loaded into the regular time fuse has burned through both rings completely in about 17.5 seconds, the extreme variation among all the fuses fired being only 0.4 seconds under a 16" vacuum. t has, consequently, been shown that such powders have unusual possibilities for use in time fuses.

The following are given by way of example of powders constructed or combined in accordance with this invention. P t

" er Cell 1. Red lead 84A Silicon 14.8 Glycerine 0.8 The burning of this powder may be represented by the following-formula:

as a result of decomposition. Per cent 5 2. Barium peroxide 83 Magnesium 12 Shellac 5 3. Red lead 88 Calcium silicide 10 Resin" 2 4. Red lead 79 Ferro-silicon 12 Aluminum 9 5. Lead peroxide i. 86

Calcium silicide 1410c It will be readily realized by those familiar with this art that other gas producing compounds than those mentioned above may be substituted therefor and that other substances may be substituted for the silicon, aluminum and magnesium, and it is within the spirit of this invention to make such substitution when desired.

I claim:

1. A delay powder for time fuses embodying an oxide of lead, silicon and a substance capable of reacting with the lead oxide and forming a binder. v

2. A delay powder for time fuses including an oxide of lead, siliconand glycerine.

3. A delay powder for time fuses embodying a metallic oxide and a silicon com ound capgble of combining with oxygen to f drm a soli a 4. A delay powder for time fuses embodying an oxide evolving oxygen upon decomposition of such oxide, a silicon compound capable of reacting with oxygen to form a solid and a binder.

5. A delay powder for time fuses embodying an oxide, silicon capable of reacting with oxygen to form a solid and a substance uniting with an element of the oxide to form a chemical compound and forming a binder.

6. A delay powder for fuses embodying a metallic oxide, a mineral adapted to react with oxygen to form a solid and 'Iycerine.

GEORGE c? n.