High "g" electronics system

Abstract

The invention concerns a technique and apparatus for protecting sensitive ectronic components against the high accelerations encountered in a tank-powered projectile, for instance. A first ring is placed on a circuit board and filled with an RTV compound. A cap is placed on the first ring to force excess RTV compound from the first ring, and is removed once the RTV compound cures. A second shorter ring is placed about the RTV compound and is attached to the circuit board. A flat plate is then used to press the RTV compound into any voids which may exist between elements mounted on the circuit board. Circuit modules created in this manner may be stacked upon one another and interconnected.

What is claimed is: 
     
       1. For a potted circuit board having elements connected bY leads, an assembly including: a first walled means for surrounding the elements and connected to the circuit board;   an insulating means for insulating the elements, filling the first walled means;   a cap means for closing the first walled means, which when placed upon the first walled means extends slightly within the first walled means;   a venting means via which an excess of the insulating means travels with the cap closed;   a second walled means shorter than and for replacing the first walled means about the insulating means, and connected to the circuit board; and   a pressing means for pressing the insulating means toward the circuit board until contacting the second walled means.   
     
     
       2. An assembly as in claim 1, the first walled means comprising a molding ring. 
     
     
       3. An assembly as in claim 2, the shock insulating compound comprising an RTV compound which fills the molding ring. 
     
     
       4. An assembly as in claim 3, the cap means comprising a round molding cap. 
     
     
       5. An assembly as in claim 4, the molding cap havinq a circular and concentric structure thereon. 
     
     
       6. An assembly as in claim 5, the circular and concentric structure comprising an alternating series of channels and ridges. 
     
     
       7. An assembly as in claim 6, the venting means comprisinq a hole in the molding cap through which the excess RTV compound travels. 
     
     
       8. An assembly as in claim 7, the venting means including a vacuum means connected to the hole, for evacuating the excess RTV compound. 
     
     
       9. An assembly as in claim 8, the second walled means comprising a second ring, shorter than the molding ring which is engaged in the molding cap. 
     
     
       10. An assembly as in claim 9, the pressing means comprisinq a flat plate which presses the RTV compound toward the circuit board, until contacting the second ring. 
     
     
       11. A method for assembling a potted circuit board having elements connected by leads, the steps including: surrounding the elements with a wall;   filling the wall with an insulating material;   capping the wall;   forcing an excess of the insulating material from within the wall;   surrounding the insulating material with a second ring;   pressing the insulating material toward the circuit board.   
     
     
       12. The method as in claim 11, including surrounding the elements with a molding ring. 
     
     
       13. The methods ad in claim 12, including filling the molding ring with a RTV compound. 
     
     
       14. The method as in claim 13, including capping the wall with a round cap. 
     
     
       15. The method as in claim 14, includinq capping the wall with a cap having a circular and concentric structure thereon. 
     
     
       16. The method as in claim 15, including capping the wall with a circular and concentric structure having an alternatinq series of ridges and channels, and forminq a complementary series of channels and ridges in the RTV compound. 
     
     
       17. The method as in claim 16, including forcing an excess of the RTV compound throuqh holes in the molding cap. 
     
     
       18. The method as in claim 17, including evacuating the excess RTV compound through the holes with a vacuum. 
     
     
       19. The method as in claim 18, including curing the RTV compound. 
     
     
       20. The method as in claim 19, including removing the molding ring and surrounding the elements with a second, shorter ring. 
     
     
       21. The method as in claim 20, including pressing the cured RTV compound with a flat plate.