Method of producing a flexible circuit and master grid therefor

[54] METHOD OF PRODUCING A FLEXIBLE CIRCUIT AND MASTER GRID THEREFOR

[75] Inventor: Reece C. Jensen, Los Gatos, Calif.

[73] Assignee: Flexmark, Inc., Fremont, Calif.

[21] Appl. No.: 71,562

[22] Filed: Apr. 27, 1987

[51] Int. CI." H05K 1/00; H05K 3/00

[52] U.S. CI 361/398; 29/846;

174/68.5; 361/400; 361/409; 361/416

[58] Field of Search 83/30, 31; 29/846, 852;

269/904, 903; 174/68.5; 200/1 R, 5 R, 5 A, 159 B, 292; 361/397, 398, 400, 403, 404, 408, 409, 410, 411, 412, 414, 416, 417, 418

[56] References Cited

U.S. PATENT DOCUMENTS

3,290,558 12/1966 Sapy 361/398 X

3,364,300 1/1968 Bradham 361/416 X

3,564,115 2/1971 Gribble et al 361/409 X

3,718,936 2/1973 Rice, Jr 361/410 X

3,886,335 5/1975 Hendricks 200/5 A X

4,055,735 10/1977 Eachus et al 200/5 A

A method of producing a flexible circuit in a predetermined pattern includes in one embodiment utilizing a flexible circuit master grid which has, on a roll of insulating material, successive grid patterns of switch arrays connected to one another. By interrupting some of the circuit paths the remaining circuit paths will provide an overall flexible circuit pattern which can than be cut out of the roll. In another embodiment a simplified flexible circuit master grid can also include orthogonal conductors arranged on the front and back of the flexible insulating layer plated with holes connecting each front conductor to a corresponding back conductor. A flexible circuit pattern is then constructed by cutting along the boundary edges of the arrays.

16 Claims, 10 Drawing Sheets