Dynamit Nobel Aktiengesellschaft

Hans Florin

Gunther Faber

Peter Roh

Peter-Josef Grommes

One fuse head has an insulating pole body with electrically conducting longitudinal strips, an incandescence bridge arranged on the pole body between the strips and connecting wires. The glow bridge and the connecting wires each being connected via soldered joints to the longitudinal strips. The fuse head also has at least one priming explosive and an external varnish finish coating covering the at least one priming explosive. To improve adherence, to facilitate the manufacturing process, to reduce the size of the solder joints, and to reduce the weight distribution of the priming explosive, it is proposed to arrange on the pole body, perpendicular to the pole body axis, grooves which are filled with priming explosive. Another fuse head has a basic module with electrically conducting pole supports running through it, the ends of the supports being connected on the ignition side via an incandescence bridge. It is proposed to arrange on the basic module at least one groove perpendicular to a longitudinal axis of the basic module, said at least one groove being filled with priming explosive.

Fuse head

In fuse elements of layered structure with long delay times, misfires, occur, above all, if aggravating secondary conditions prevail (such as, for example, high projectile rotation and/or temperature stresses and shock stresses). The safe progression of the reaction through the element is enhanced by providing that, as seen in the propagation direction of the reaction, the central zone of a charge igniting a delay charge projects into a central region of the delay charge. An additional improvement can be achieved by interposing between the ignition charge and the delay section, one or several relay charges and by making the choice of the charge components so that the discontinuities of the characteristic values (especially of the reaction rate) become more even and thus smaller, or by utilizing an ignition charge having a particularly low reaction rate.

Fuse element, preferably with long delay period and method for producing

Pyrotechnic delay compositions with delays in the seconds range are based on a pyrotechnic delay mixture of powdered metallic tungsten, barium chromate an potassium perchlorate, and additionally contain either barium hexafluorosilicate or calcium fluoride pyrogenic silica. The additives cause these compositions to burn completely even under severe environmental conditions, such as very fast rotation, vibration, impact, shock, and, at the same time, extremely low below-freezing temperatures. The effect of the barium hexafluorosilicate is still further improved if the delay compositions additionally contain pyrogenic silica.

Pyrotechnic delay compositions

A nonelectric delay detonator has, in a casing, a secondary charge as well as a delay device. The delay detonator is initiated by an ignition transfer hose extending into the casing. A partition is arranged between a hose end and the delay device. Ignition of the delay device is effected by the hose by impact or heat. An auxiliary charge (e.g. a primer cap) is located on the other side of the partition, this auxiliary charge ignites a delay charge of the delay device. In this way, the delay device burns in a closed system from which gas and pressure cannot escape into the hose. Thereby the scattering width of the delay times of the detonator is reduced.

Delay detonator

A nonelectric delay detonator has means for allowing an ignition flame to be transmitted from an ignition transfer hose to a delay device. The delay device causes a secondary charge to detonate after a predetermined delay time. In order to obtain reproducibile delay times of the delay device, a check valve is arranged between one end of the ignition transfer hose and the delay device; this check valve being opened for a short time period due to the excess pressure in the hose and permitting the ignition flame to pass through. During deflagration of the delay device, the check valve is closed again so that the delay device burns within a closed system. In this manner, undefined pressure and gas losses are avoided.

Growing community of inventors

Troisdorf, Germany

Hans Florin