Hand-holdable gun for longitudinal extrusion of a thermoplastic-type medium therefrom and removable heat sleeve therefor

A removable hollow heating sleeve for use in a hand-holdable gun for longitudinally extruding a thermoplastic typemedium from a removable self-contained storage cartridge container therefor in response to piston pressure along the longitudinal axis of said container wherein said gun contains a longitudinally movable piston means for applying said piston pressure along said container longitudinal axis and said cartridge container includes a plunger means movable along said longitudinal axis of said cartridge container in response to said piston pressure, and an outlet for enabling said piston pressure responsive extrusion therefrom, said thermoplastic medium longitudinal extrusion being dependent on the temperature of said thermoplastic medium during said piston pressure responsive extrusion;

• said removable hollow heating sleeve having an internal diameter sufficient to surround said cartridge container for providing a controlled temperature to said heat sleeve surrounded thermoplastic type medium during said piston pressure responsive extrusion to enhance the flowability of said thermoplastic type medium from said cartridge container independently of the ambient temperature outside said heating sleeve, said heating sleeve comprising a first heat reflective sleeve surrounding said cartridge container for reflecting heat toward said hollow sleeve interior for providing said controlled temperature thereto, an electric heating coil surrounding said first heat reflective sleeve for heating said hollow heat sleeve interior to said controlled temperature in response to a voltage applied thereto, and a first heat transmissive removable burst shield sleeve within the interior of said first heat reflective sleeve and at least partially surrounding said heat sleeve surrounded cartridge container to provide at least a portion of a complete burst shield protective enclosure therefor physically isolating said heat sleeve first reflective sleeve and heating coil from said cartridge container to prevent fouling thereof in the event of a burst of said cartridge container while enabling heating of said thermoplastic type medium within said cartridge container to said controlled temperature, said heating sleeve comprising a second heat reflective sleeve surrounding said heating coil for reflecting heat toward said hollow heating sleeve interior, said first and second heat reflective sleeves sandwiching said heating coil therebetween, and an end cap at one end of said heating sleeve having an opening therein for receiving said extrusion outlet of said surrounded container therein, whereby said thermoplastic type piston pressure actuated extrusion may be readily accomplished independent of the outside ambient temperature of said storage container therefor.