Chassis arrangement for reducing flame emissions

Abstract

A chassis arrangement that minimizes lateral flame spread from card to card within the chassis, and increases heat dissipation from the chassis, comprising a heat sink attached to the inside of the chassis cover to dissipate excess heat from within the chassis, and PCB shields disposed between the circuit cards of the chassis and acting in concert with the heat sink to act as physical and thermal barriers to prevent lateral flame spread from card to card due to flame and hot gas wrap-around.

What is claimed is:  
     
         1 . A chassis arrangement for reducing flame emissions, a chassis and chassis cover defining an internal compartment having printed circuit board (PCB) cards installed within, said chassis arrangement comprising: 
 a heat sink thermally coupled to the bottom face of the chassis cover so as to allow the transmission of excess heat from the internal compartment through said heat sink and the chassis cover and to the environment; and    PCB shields disposed between the PCB cards, said PCB shields acting as physical and thermal barriers between adjacent PCB cards, said PCB shields acting in concert with said heat sink to prevent or reduce lateral flame spread from PCB card to PCB card due to flame wrap-around and to direct excess heat toward said heat sink.    
     
     
         2 . A chassis arrangement according to  claim 1 , wherein the top edges of said PCB shields are approximately flush with the bottom face of said heat shield.  
     
     
         3 . A chassis arrangement according to  claim 1 , wherein the top edges of said PCB shields are approximately flush with the bottom face of said heat shield, and the front and rear edges of said PCB shields are approximately flush with the front and rear faces, respectively, of the internal compartment.  
     
     
         4 . A chassis arrangement according to  claim 2 , further comprising non-flammable material attached to the chassis cover, adjacent to said heat sink, and approximately flush with the top edges of the PCB cards, said non-flammable material acting in concert with said heat sink to prevent or reduce lateral flame spread from PCB card to PCB card due to flame wrap-around.  
     
     
         5 . A chassis arrangement according to  claim 1 , the chassis further comprising a forced air cooling system, said chassis arrangement further comprising a thermal fuse acting to shut down the forced air cooling system, thereby reducing the venting of hot gasses or flames outside the chassis.