Two-phase projectile

Abstract

A device for transferring energy to propel a payload with added velocity after launch includes a first component having a mass (m 1 ), and a second component having a mass (m 2 ). As an assembly, the first and second components are positioned to establish a compression chamber between them that is dimensionally responsive to their relative movements. And, a payload is mounted on a selected component of the assembly. In operation, a driving force is exerted against one component of the assembly to propel the entire assembly along a predetermined flight path. Contemporaneously with this acceleration, the two components are moved toward each other. In turn, this compresses gas in the gas chamber to generate potential energy that is transferred as the gas expands to separate the payload from the assembly with added velocity.

What is claimed is: 
     
         1 . A device which comprises:
 a first component, wherein the first component is tubular shaped, is formed with a lumen and defines an axis, and wherein the first component has an open end and a closed end;   a second component engaged with the first component to create an assembly, wherein the assembly provides for a back and forth axial movement of the second component in the lumen of the first component, and establishes a gas-filled compression chamber in the lumen of the first component between the second component and the closed end of the first component;   a payload mounted on a selected component of the assembly; and   a launcher for generating an axially-directed driving force on the assembly to propel the assembly from the launcher and onto a flight path in the axial direction with an initial relative movement between the first component and the second component to compress gas in the compression chamber and generate potential energy in the compressed gas for use in separating the payload from the assembly in flight.   
     
     
         2 . A device as recited in  claim 1  wherein, during an initial acceleration of the assembly by the driving force, a first kinetic energy is generated for the first component and a second kinetic energy is generated for the second component of the assembly, and a potential energy is generated for the gas in the gas-filled chamber of the assembly. 
     
     
         3 . A device as recited in  claim 2  wherein, after the initial acceleration of the assembly, the potential energy of the gas is transferred into kinetic energy with an expansion of the gas to accelerate the payload for separation of the payload from the assembly and to decelerate any remainder of the separated assembly. 
     
     
         4 . A device as recited in  claim 1  wherein the second component is a cartridge for holding the payload, and the driving force is generated on the first component, and further wherein the payload is separated from the second component, in flight, after launch. 
     
     
         5 . A device as recited in  claim 1  wherein the payload is mounted on the first component and the driving force is applied to the second component. 
     
     
         6 . A device as recited in  claim 1  wherein the launcher is man-powered. 
     
     
         7 . A device as recited in  claim 6  wherein the launcher is a vertical bow. 
     
     
         8 . A device as recited in  claim 6  wherein the launcher is a crossbow. 
     
     
         9 . A device as recited in  claim 1  wherein a mass (m 1 ) of the first component is not equal to a mass (m 2 ) of the second component. 
     
     
         10 . A device which comprises:
 a first component having a mass (m 1 );   a second component having a mass (m 2 ), wherein the first component and the second component are positioned in an assembly for relative movement therebetween;   a payload mounted on a selected component of the assembly; and   an enclosed gas chamber established between the first and second components, wherein the gas chamber is dimensionally responsive to movements between the first and second components for compressing gas in the gas chamber to generate potential energy in the compressed gas for subsequent use as the gas expands to separate the payload from the assembly.   
     
     
         11 . A device as recited in  claim 10  wherein the first component is tubular shaped, is formed with a lumen and defines an axis, and wherein the first component has an open end and a closed end, and further wherein the assembly establishes a gas-filled compression chamber in the lumen of the first component between the second component and the closed end of the first component, and provides for a back and forth axial movement of the second component in the compression chamber. 
     
     
         12 . A device as recited in  claim 11  further comprising a launcher for generating an axially-directed driving force on the assembly to propel the assembly from the launcher and onto a flight path in the axial direction with an initial relative movement between the first component and the second component to compress gas in the compression chamber and generate potential energy in the compressed gas for use in separating the payload from the assembly in flight. 
     
     
         13 . A device as recited in  claim 12  wherein the second component is a cartridge for holding the payload, and the driving force is generated on the first component, and further wherein the payload is separated from the second component. 
     
     
         14 . A device as recited in  claim 12  wherein the payload is mounted on the first component and the driving force is generated on the second component. 
     
     
         15 . A device as recited in  claim 12  wherein the launcher is man-powered. 
     
     
         16 . A device as recited in  claim 12  wherein the launcher is a vertical bow. 
     
     
         17 . A device as recited in  claim 12  wherein the launcher is a crossbow. 
     
     
         18 . A method for transferring energy to propel a payload, the method comprising the steps of:
 providing an assembly, wherein the assembly includes a first incompressible component having a mass (m 1 ) and a second incompressible component having a mass (m 2 ), and a compressible component aligned along an axis extending between the first and second incompressible components, wherein the compressible component is responsive to relative movements between the first and second incompressible components;   mounting the payload on the second incompressible component of the assembly;   exerting an axially directed driving force against a selected incompressible component to establish a kinetic energy for the assembly, and to cause the first and second incompressible components to move along the axis toward each other;   generating a potential energy in the assembly as the compressible component is compressed between the first and second incompressible components in response to relative movements thereof; and   converting the potential energy generated in the compressible component into kinetic energy with equal and opposite forces acting respectively against the first and second incompressible components to dissipate kinetic energy in one incompressible component, to increase kinetic energy in the other incompressible component and to cause separation of the payload from the assembly with increased velocity.   
     
     
         19 . A method as recited in  claim 18  wherein the compressible component is a gas. 
     
     
         20 . A method as recited in  claim 18  wherein the exerting step is accomplished using a man-powered launcher.