Abstract: A system for determining the optimal settings for parameter of a stencil printing machine. The system generates a model mapping parameter inputs to output results. The model is then used to determine the optimal settings of parameter inputs in order to produce the desired results. One form of mapping is to generate a neural network model of a system. The neural network is generated from data that includes multiple sets of input parameter settings and the resulting output associated with the inputs. Back propagation is then performed on the neural network to determine the optimal settings.

Abstract: Allowing printed circuit boards to be secured in a printed circuit carrier by means of a retaining bar that is secured at its ends to the printed circuit board carrier. Contact is established between the retaining bar and each individual printed circuit board by depositing a copper area on the back face of the printed circuit board and making contact with this area by the retaining bar. The conductive area is connected to the ground of the printed circuit board, and the retaining bar is conductive in nature and makes contact at either end with the printed circuit board carrier. The retaining bar is designed to provide vertical strength throughout its length.

Abstract: The precise solder paste application process makes use of mask registration apertures that are formed in the printed circuit board and that are adapted to receive a component solder paste mask that conforms to the conductor pattern of the component to be replaced. The component solder paste mask comprises a mask that has formed therein apertures that correspond to the pattern of solder paste that is to be applied to the printed circuit board surface mount pads to correspond to the conductors of the component. The component solder paste mask includes registration features that mate with the registration apertures formed in the printed circuit board to thereby ensure precise placement of the component solder paste mask over the area of the printed circuit board that receives the replacement component.

Abstract: A metallic RF or thermal shield (200, 200', 200") has a non-perforated area (202) around its center of mass, of a radius (203) sufficient for pick-up and placement of the shield by automatic vacuum pick-up equipment during automated surface-mount circuit assembly.