Abstract: An electrothermal gun uses an apparatus for generating high gas pressure. The apparatus includes a receiver having a combustion chamber for holding a propellant which produces a gas component and a particle component when the propellant undergoes an exothermic chemical reaction, and a flow passageway positioned downstream of the combustion chamber. An ignition mechanism causes the propellant contained in the combustion chamber to undergo the exothermic chemical reaction. A separator in the flow passageway substantially separates the particle component from the gas component in the flow passageway. The gun includes a barrel connected to the receiver and communicating with the flow passageway. By substantially stopping the particle component, namely metal oxide, from reaching the barrel, wear on the barrel is reduced.

Abstract: An electrothermal gun uses an apparatus for generating high gas pressure. The apparatus includes a receiver having a combustion chamber for holding a propellant which produces a gas component and a particle component when the propellant undergoes an exothermic chemical reaction, and a flow passageway positioned downstream of the combustion chamber. An ignition mechanism causes the propellant contained in the combustion chamber to undergo the exothermic chemical reaction. A separator in the flow passageway substantially separates the particle component from the gas component in the flow passageway. The gun includes a barrel connected to the receiver and communicating with the flow passageway. By substantially stopping the particle component, namely metal oxide, from reaching the barrel, wear on the barrel is reduced.

Abstract: Hard material can be displaced by firing a frangible projectile from a firing device. The projectile has a rear portion that engages the bore of the barrel of the firing device and a front portion that is rotatably journaled to the rear portion. The front portion can be frangible to allow maximum displacement of the hard material. Specifically, the front portion has a core and a plurality of fins extending from the core. At impact, as the fins penetrate the target, the fins separate from the core and spread radially outwardly from the core.

Abstract: An identification/security tag system, including miniaturized tags which can be readily concealed, utilizes a concept of "electronic" Doppler shifting to generate a frequency shifted signal in response to an interrogation signal. The frequency shifted signal is used to identify individual tags. The implementation of electronic Doppler shifting permits the utilization of conventional police/sport radar guns as a combined transmitter and receiver unit, thereby greatly reducing the expense of the system. The high frequency operation of the system permits size of the tag to be significantly reduced with respect to the size of tags used in conventional tag systems. Rectenna circuitry is further employed to eliminate the need for an active power supply in the tag in some applications.