| 摘要 |
1531677 Circuit assembly DAINI SEIKOSHA KK 7 April 1977 [16 April 1976] 14807/77 Heading H1R An electronic circuit, e.g. for a watch, is constructed (Figs. 4, 6) of an insulant substrate 5 of, e.g. ceramic, glass, or epoxy resin carrying a printed circuit 6 and recessed to house an electronic component. A frame 11 larger than the recess is formed of thermoplastic resin and disposed round the recess; the substrate being placed on heater 12 and the frame being thermally bonded on by pressure plate 13. A component 9 is fixed by adhesive 8 in the recess 7 and its contact pads are wire bonded to the circuit 6; after which the cavity within the frame and substrate is filled with potting compound. In modifications (Fig. 8, not shown) deformation of the frame is prevented by insertion in an outer reinforcing frame during thermal bonding and (Fig. 9, not shown) the frame is held in an apertured air-chuck during pressure bonding. In a further modification (Fig. 11) a monolithic chip 19 comprising light emitting diodes is bonded directly to the substrate 18 and a frame 20 of thermoplastic material is thermally bonded thereto. The chip is then moulded in settable transparent resin 21 potted in the region within the frame. In a further modification (Fig. 12) a flexible substrate 22 is apertured at 26 for electronic component 25 bonded directly to a printed circuit pattern 24 of the substrate, and a frame 26 of thermoplastic resin has a base 27 surrounded by a side wall 28 bonded by heat and pressure to the substrate. A further frame 29 is formed on the reverse face of the substrate by printed circuit techniques, and the component is potted in settable resin (Fig. 13, not shown) whose flow along the reverse face is inhibited by frame 29. In a further modification (Fig. 14) a resist 31 of, e.g., epoxy resin, is screen printed on substrate 5 to overly the circuit pattern surrounding the recess 7, and a larger frame 11a of thermoplastic or thermosetting resin is disposed on the substrate to surround the aperture while the resist is liquid, and thermally bonded; after which component 9 is mounted and potted in by resin 14. |
