摘要:
A method and apparatus are provided for increasing the energy of chirped laser pulses to an output in the range 0.001 to over 10 millijoules at a repetition rate 0.010 to 100 kHz by using a two stage optical parametric amplifier utilizing a bulk nonlinear crystal wherein the pump and signal beam size can be independently adjusted in each stage.
摘要:
A method for chopping a body consisting of explosives is described, by which a high-pressure water jet emerging from a nozzle is directed against the body of solid explosive and in which the nozzle and the body carry out a movement relative to each other during the chopping. Preferred fields of use are composite rocket fuels. There is also described a device for carrying out the process, in which the body of composite rocket fuel to be decomposed or divided into portions is secured on a chopping bench, and a nozzle fastened to a nozzle holder for the high-pressure water jet as well as at least one means for producing a relative movement serving as chopping advance movement between the nozzle and the body of composite rocket fuel are provided.
摘要:
There is disclosed a tying machine (100) for forming bundles from a plurality of propellant sticks (4). Such bun-files may be used to form a propellant charge for use in, for example, heavy artillery. The tying machine tends to comprise an aperture (6) and a work surface (8) such that the plurality of sticks may rest on the work surface and occupy a portion of the aperture. Further, a drum (10) holding one end of a length of twine surrounds the aperture and can be rotated to wind the twine around the sticks. The twine can be secured once the sticks are bound.
摘要:
A method for mass producing and loading explosive charges in detonators, ds, relays, primers, etc., utilizing the explosive charges each in sheet form. Sheets corresponding to the various increments, each containing the finely divided high explosive and binder therefor, are superposed in the proper order preferably on a sheet of closing disc material, and the resulting structure of layered sheets is cored to produce the explosive train. The coring can be accomplished with a battery of cutters so that large numbers of explosive trains can be cut to size simultaneously. The explosive train cores thus obtained can be pushed out of the cutters into cups, which are then crimped and sealed.
摘要:
A method and apparatus are provided for increasing the energy of chirped laser pulses to an output in the range 0.001 to over 10 millijoules at a repetition rate 0.010 to 100 kHz by using a two stage optical parametric amplifier utilizing a bulk nonlinear crystal wherein the pump and signal beam size can be independently adjusted in each stage.
摘要:
A cutting assembly for cutting propellant from a rocket motor. The cutting assembly includes a plurality of first cutting wheels, second cutting wheels and secondary cutters which are mounted to a mounting head. The mounting head is attached to an arm for rotation about an axis of rotation. Means are provided for rotating the mounting head. The cutting wheels are mounted to the mounting head for rotation about an axis of rotation transverse to the axis of rotation of the mounting head. Each cutting wheel includes a plurality of cutting blades extending outwardly from the rim. The cutting blades are each configured with a radially extending cutting edge for cutting in a direction substantially normal to the axis of rotation of the mounting head. The cutting blades are oriented at an approximate 30 degree angle to the axis of rotation of the first cutting wheel, with the angle of orientation of the cutting blades of the second cutting wheels being opposite in direction to the angle of orientation of the cutting blades of the first cutting wheels. The secondary cutters include a substantially circular cutting blade for making cuts in the propellant which are substantially transverse to the cuts made by the first and second cutting wheels.
摘要:
The present invention is a method for penetrating a workpiece using an ultra-short pulse laser beam without causing damage to subsequent surfaces facing the laser. Several embodiments are shown which place holes in fuel injectors without damaging the back surface of the sack in which the fuel is ejected. In one embodiment, pulses from an ultra short pulse laser remove about 10 nm to 1000 nm of material per pulse. In one embodiment, a plasma source is attached to the fuel injector and initiated by common methods such as microwave energy. In another embodiment of the invention, the sack void is filled with a solid. In one other embodiment, a high viscosity liquid is placed within the sack. In general, high-viscosity liquids preferably used in this invention should have a high damage threshold and have a diffusing property.
摘要:
The invention consists of a method for machining (cutting, drilling, sculpting) of explosives (e.g., TNT, TATB, PETN, RDX, etc.). By using pulses of a duration in the range of 5 femtoseconds to 50 picoseconds, extremely precise and rapid machining can be achieved with essentially no heat or shock affected zone. In this method, material is removed by a nonthermal mechanism. A combination of multiphoton and collisional ionization creates a critical density plasma in a time scale much shorter than electron kinetic energy is transferred to the lattice. The resulting plasma is far from thermal equilibrium. The material is in essence converted from its initial solid-state directly into a fully ionized plasma on a time scale too short for thermal equilibrium to be established with the lattice. As a result, there is negligible heat conduction beyond the region removed resulting in negligible thermal stress or shock to the material beyond a few microns from the laser machined surface. Hydrodynamic expansion of the plasma eliminates the need for any ancillary techniques to remove material and produces extremely high quality machined surfaces. There is no detonation or deflagration of the explosive in the process and the material which is removed is rendered inert.