US1765294A

US1765294A - Delay-action detonator

Info

Publication number: US1765294A
Application number: US328004A
Authority: US
Inventors: Gilbert C Bacon
Original assignee: Atlas Powder Co
Current assignee: Atlas Powder Co
Priority date: 1928-12-22
Filing date: 1928-12-22
Publication date: 1930-06-17
Anticipated expiration: 1947-06-17

Description

Fild Dec. 22, 1928 lllllllllllilllnllll \llll II I Ill I. v m M l 6 7 2 2 9 n f I I l llllllllllllllllll I|l|..l| llllllllllllllllllll: llllll Illllllllllllll |||l|l\ INVENTOR CHLB RT C. BAC ON ATTORNEY ii atented June 31?, 39.536?

A N OFFI' stars-3r c. BACON, or TAMAQUA, PENNSYLVANIAL'ASSIGNOB 'ro ATLAS POWDER CC'FR'IIEANY, or WILMINGTON, DELAWARE, A conronsrron or DELAWARE DELAY-ACTION DETONATOR Application filed December 22, 1928 Serial No. 328,004.

This invention 'relates to delay action detonators, and ithas for its objects to provide an improved device of this character constructed in such manner that any possibility of preignition of either the priming charge or ofthe main charge, will be-efi'ectually guarded against. Further objects and advantages of the invention will be set forth in the detailed description which follows:

In the accompanying drawing Fig. 1 is'a magnified vertical sectional viewof a detonator constructed in accordance with the invention. Fig. 2 is a side elevation thereof. Fig. 3 is adetailed side view of .a flame tube hereinafter described, and Fig. 4 is a detailed side view of a delay tube hereinafter described. Like numerals designate corresponding parts in all of the figures .of the drawing. I Referring to the drawing, 5 designates the main shell of the detonator in which a suitable priming charge 6, such as fulminate of mercury, or likeinitiating explosive, is located. An electrical igniting element 7 is sealed within the outer end of the shell by the sealing'inaterial8. This igniting ele ment is of a well known and conventional form, its lead wires being indicated at 9 and 10. A delay tube 11 of relatively heavy material is filled with a suitable combustible delay material 12. A suitable material for this purpose is black powder, though it is to be understood that -many other materials may be'employed in lieu thereof. This black powder is compressed into the tube 11 to a relatively high density. The purpose of compressing the delay material to a condi-- tion of high density is to insurethat the delay ;material of difierent detonators will be of substantially the same density, so that the'timing of the explosion of one detonator with respect to the timing ofthe explosion of another detonator may be accurately controlled. A flame-tube'13 is located betweenthe head 14 of the igniting deviceand-the delay material. This flame tube is of spoollike formation, that is to say, it has heads 13.-A at its opposite ends, and a portion of reduced diameter 13' B between said heads.

It is further provided with-a longitudinal passage-way 15, and a transverse discharge opening 16, which leads from the passage 15 to the side of the flame tube at a point between its heads. The heads 13A of the flame tube arealmost equal in diameter to the internal diameter of the shell 5, though the fit of the flame tube within the shell is aloose one. A flame shield 17 in the form of an auxiliary shell of larger diameter than the shell 5 surrounds the latter from its outer end to a point below' the flame tube. The shell 17 and the shell 5 are rolled or crimped inwardly as indicated at 18 into an annular recess 19 of the delay tube, whereby all of these parts are securely held together. When" the circuit is closed through wires 9 and 10 and the element 14 here shown-as amatch. head, isignited, the flame from the delay material pass upwardly through they 4 passage 15 and out of the opening 16 into the annular recess 20, formed between the tube 5 and the reduced portion 13B of .the flame tube, These gases then pass around the flame tube to and through an opening 21 in the wall of the shell 5 to the space between the flame shield 17 and the shell 5, and are dis- I charged from said space'at the upper or outer end of the detonator.

Very important advantages flow from the above described construction, in that: since the delay tube is of a relatively thick material, it absorbs enough of the heat genera-ted by the burning of the delay material to guard against the heating up of the lower part .ofthe main shell of the detonator to such an extent as to bring about preignition of the fulminate. Inaddition the construe-- onator is embedded-in use. the fact that the body of the detonator at Lveaeee tion is such as to effectually guard against preignition of the main charge of dynamite, powder; or other explosive, in which the det- This is due to the point of generation of the greatest heat does not come in contact with the explosive at all, but is held in spaced relation thereto by the presence of the flame shield. The gases are caused to travel through so long a path that they have time to cool before they pass from the detonator, that is to say, these gases must pass first through the flame tube then around the flame tube and then through sub stantially the entire length of the shield 17 before they pass from the detonator. Certain kinds of delay materials, of whichblack powder is an example, leave a, residue of considerable ash, and the arrangement described is such as to guard against the possibility of this ash clogging up the escape ports of the gases. If theseescape ports were to become clogged, it would result in the building up of such internal pressure in the generator as to causethe delay material to burn much more rapidly than would otherwise be the case and it is clear that this would result in reducing the intended period of delay. The placing of the flame tube between the delaytube and the igniter serves to eliminate two of the primary causes of premature detonation. It is highly des rable to use a lateral vent for the gases, of the character of that shown by the applicant, it being found, in practice, that a lateral vent ofthis nature may be made water tight with much less difiiculty than a longitudinal vent. However, with the lateral vent and no flame tube; the ash from the burning delay mate rial tends to close the outlet, resulting in the creation of a pressure within the detonator, and a consequent irregularity in the delayinterval accompanied by the possibility of premature explosion. Likewise, with the lateral vent, and in the absence of the flame tube, the heat from the burning delay material' is likelyJco bring about ignitionor premature explosion of the explosive in which the delay action electric detonator is inserted.- In case of premature explosion,

the proper, sequence of delayed blasts is, of course, disturbed. In case of ignition, the.

burning explosive may explode the detonator charge before it is regularly exploded by the delay tube. This would also disturb the proper sequence.

The placing of the flame tube between the 'dela tube and the igniter cools the gases pro uced by the burning of the delay material to such a point that'theydo not ignite the surrounding body of high explosive, and it also causes the deposit of the greater part of the ash from the delay material before the vent is reached, and in this manner eliminate's the blocking of the vent. Therefore,

it will be seen that a flame tube is essential to the proper action of the desirable lateral or side wall vent. The particular shape of this flame tube is not of the essence of the invention since it is clear that other shapes may be resorted to, while retaining the advantages above outlined. In the manufacture of the detonator, the opening 21, between the shell 5 and the interior of the flame shield is covered with a suitable sealing material, such, for example, as .a nitrocellulose lacquer. This material has several important advantages, in that it is waterproof,

.it adheres very securely and firmly to the sumed, to open the vent at the time of use 1 of the detonator, being suflicient.

It is to be understood that the invention is not limited to the precise arrangements shown and described, but that it includes within its purview whatever changes fairly come within either the terms or the spirit of the appended claims. 2

Having described my invention what I claim is:

1. A delay action detonator comprising a main shell, a priming charge therein, a delay tube in the shell containing a combustible delay material, an electric igniter and a separate flame tube within the shell and between the gniter and the delay material.

2. A delay action detonator comprising a main shell, a priming charge therein, a delay tube in the-shell containing a combustible delay material, and an electric igniter and a separate flame tube in the main shell between the igniter and the delay material, said flame tube having alongitudinal passage-way there-through,'and' a lateral diseharge opening leading from saidpassageway through the side of the flame tube.

3. A delay action detonator comprising a main shell, a priming charge in the lower end thereof, a delay tube containing a comin its wall within the length of the flame tube. V

p 4. A delay action detonator comprising a shell, '3. priming charge in the inner end thereof, a combustible delay materiallocated between the igniter. and the priming charge, and a flame tube between the delay material and the igniter, said flame tube comprising a body having heads-at its ends of approximately the'interior diameter of the shell and a reduced; intermediate portion connecting said heads, said flame tube having an opening formed longitudinally there-throughwith a lateral discharge opening. in its portion of reduced diameter and said shell having an opening formed in its wall within the length of the flame tube.

5. A delay action'detonator comprising a shell, a priming charge in the inner end thereof, a combustible-delay material located between the igniter and the priming charge,

and a flame tube betweenthe delay materlal and the igniter, said flame tube comprising a body having headsat its ends of approximately the interior diameter of the shell and a reduced intermediate portion connecting said heads, said flame tube having an opening formed longitudinally there-through with a lateral discharge opening in its portion of reduced diameter and said shell having an opening formed in its wall within the length of the flame tube but at a point oil-set with respect to the discharge opening of the flame tube.

6. A delay action detonator comprising a shell, a priming charge in the inner end thereof, a combustible delay material located between the igniter and the priming charge, and a flame tube comprising a body having heads at its 'ends, of approximately the interior diameter of the .shell and a reduced intermediate portion connecting said heads, said flame tube having an opening formed longitudinally there-through with a lateral discharge opening in its portion of reduced diameter and said shell having an opening formed in its wall within the len flame tube, but at. a point off-set with respect to the discharge opening of the flame tube,

said tube having an opening formed in its wall at a point within the length of the flame tube, but at a point substantially diametri= cally opposite to the discharge opening of the flame tube.

7-. In a delay action detonator, a main shell, a priming charge therein, a combustible delay material, an electric igniter, a sep arate flame tube within the shell between the igniter and the delay material having a longitudinal passage there-through, and a lateral discharge opening, there being an opening formed in the. shell within the length of the flame tube and a flame shield outside of said shell which receives the gases h of the discharged from the opening of the first named shell.

8. In a delay action detonator, a main shell, a priming charge therein, a combustible delay material, an electric igniter, a se priming charge and having-a cumbustible delay material therein, an electric igniter outwardly of the delay tube, a flame tube of spool-like formation between the igniter and the delay tube and lying in contact with the latter, said flame tube having a longitudinal passage-way there-through and a lateral discharge opening. at a point intermediate its ends. v 1

10. A delay action detonator comprising a shell, a priming charge therein, a delay tube of much thicker material than the shell of the detonator secured within said shell outwardly of the priming .charge and hav- "ing a combustible delay material therein,

an electric igniter outwardly of the delay tube, a flame tube of spool-like formation between the igniter and the-delay tube' and lying in contact with the latter, said flame tube having a longitudinal passage-way there-through and a lateraldischarge opening at a point intermediate its ends, there being a lateral discharge opening formed in the detonator shell within the length of said flame tube.

11. A delay action detonator comprising a shell,-a priming charge therein, a delay tube of much thicker material than the shell of the detonator securedfwithin said shell outwardly of the priming charge and having a combustible delay-material therein, an electric igniter -outwardly of the delay tube, a flame tube of spool-like formation between the igniterand the delay tubeand lyingin contact with the latter, said flame tube having a longitudinal passage-way there-through and a lateral discharge opening at a point intermediate its ends, there .being a lateral discharge" opening formed in the detonator shell within the length of the flame tube and a flame shield upon the exterior of said shell into which the gases passing through said opening discharge.

12. A delay action detonator comprising a. shell, a priming charge therein, a delay t'ube of .much thicker material than the arate flame tube within the shell between t e 7 there shell of the detonator secured within said ;shell outwardly of the priming charge and formed in the detonator shell within the length of the flame tube and a flame shield upon the exterior of said shell into which the gases passing through said opening discharge, said flanie shield being closed at its inner end and open at is outer end and extending from a point inwardly of the'igniter to substantially the outer end of the shell of the detonator. 1

13. A delay action detonator comprising a shell, a main charge in the shell, a delay tube in the shell outwardly of the main charge, a lateral discharge opening in the side Wall of the shell, and a flame tube within the shell between the lateral dis charge opening and the delay tube, said flame tube being separate from and in addition to the shell.

14. A delay action detonator comprising a shell, a main charge in the shell, a delay tube in the shell outwardly of the main charge, a lateral discharge opening in the side wall of the shell, a relatively thick flame tube within the shell which is separate from and in addition to. the said shell between the lateral discharge opening and the delay tube, said flame tube being separate from and in addition to the shell, and a flame shield outwardly of the shell at the point of discharge of the lateral discharge opening and lying in spaced relation thereto.

15. A delay action detonator comprising a shell, a main charge in the shell, a-delay tube in the shell outwardly of the main charge, a lateral discharge opening in the side wall of the shell, a relatively thick flame tube within the shell which is separate from and in addition to the said shell, between the lateral-discharge opening and the delay tube, and a flame shield surrounding the shell and lying in spaced relation thereto,, and extending from a point below said lateral discharge opening to a point adjacent the upper end of the shell.

16. A delay action detonator comprising a shell, a main charg in the shel1,'a delay tube in the shell outwardly of the main charge, a discharge opening in' the shell, and a flame tube within the shell between the discharge opening and the delay tube, said flame tube being of a material materially thicker than the metal of the shell to adapt it to constitute a heat absorbing agent 17. A device of the character described,

comprising a main charge, a delay tube, a flame tube and igniting element, an integral one piece main shell in which all of said parts are contained, and a flame shield carried. by said shell, said flame tube being thicker than and in addition to the said shell. I I

18. A delay action detonatorcomprising a main charge, a delay tube, a flame tube and an igniting element, a one-piece integral shell of substantially uniform diameter throughout its length in which all of the said parts are contained, said flame tube being thicker than and in addition to the said shell, said shell being provided with a lateral gas discharge opening adjacent the flame tube, and a flame shield upon the exterior of the shell and extending about said shell at a point opposite the gas discharge opening.

In testimony whereof I have aflixed my.

signature. GILBERT C. BACON.