Paul BryanEnglewood, NJ

4696231, Sep 29, 1987

Feb 25, 1986

6/832777

Paul J. Bryan - Hewitt NJ

E. I. Du Pont de Nemours and Company - Wilmington DE

F42B 310
F42C 1908

1022025

Delay detonators can be made to function reliably at reduced distances from a neighboring detonation by increasing the weight of the detonator's priming charge. Detonators containing about 0. 26 g or more of lead azide perform reliably 12. 7 cm from a detonation in a shock resistance pipe test, and this performance is reflected in high performance in trenching operations. The higher energy output of the heavier primer charge may compensate for a decrease in the base charge's sensitivity as the detonator shell is deformed or collapsed by shock.

4299167, Nov 10, 1981

Apr 28, 1980

6/144535

Paul J. Bryan - Hewitt NJ

E. I. Du Pont de Nemours & Co. - Wilmington DE

F42B 310

1022023

A surface delay device which exhibits good precision in delay timing when it is ignited from the side output of a low-energy detonating cord (LEDC) trunkline and end-initiates an LEDC trunkline or downline has a percussion-sensitive ignition charge wedged between the integrally closed end of a metal shell and the end of a delay capsule, which houses the delay and priming charges. An orifice in the end of the delay capsule between the ignition and delay charges is kept free of the ignition charge, e. g. , by providing an axial recess in the end of the shell extending at least as far as the orifice. In the field the end of a cord is fitted into a well which is seated in the main detonating charge, adapted to be initiated by the priming charge; and another cord is positioned transversely against the ignition end of the shell.

4335652, Jun 22, 1982

Aug 11, 1980

6/177210

Paul J. Bryan - Hewitt NJ

E. I. Du Pont de Nemours & Company - Wilmington DE

F42C 1500

1022021

The ignition assembly of a non-electric delay detonator which is adapted for field-assembly with a low-energy detonating cord has an expansion shell provided with a cavity into which the cord is inserted at the time of use. The pressure pulse resulting from the detonation of the cord causes the shell to expand and an ignition charge to be actuated as a result of sudden compression between the expansion shell and a rigid ignition capsule. The burning ignition charge causes the ignition of a delay charge, which in turn ignites a priming charge, causing the base charge to detonate. The presence of ignition charge in an annular spacing between the expansion shell and ignition capsule walls, as well as between the shell and capsule ends, and the proper positioning of a cord-gripping means, preferably in the shell cavity, assure actuation of the ignition charge whether or not the cord is shoved to the bottom of the shell.

4369708, Jan 25, 1983

Sep 21, 1979

6/077718

Paul J. Bryan - Hewitt NJ
Daniel R. Morse - Bloomingdale NJ

E. I. Du Pont de Nemours and Company - Wilmington DE

F42B 316

10220213

A delay blasting cap having improved uniformity and predictability of delay time, and less susceptible to timing change as a result of a change in the medium or temperature surrounding the cap, has a polyolefin or polyfluorocarbon carrier capsule or tube for the delay charge, and preferably a rigid metal capsule holding the delay charge in place. Preferably, the delay carrier is a polyethylene capsule, which inhibits the priming charge from penetrating into the delay charge during the assembling of the cap.