Touch control panel for induction heating cook-top

United States Patent m

Tucker

[ii] 4,149,217 [45] Apr. 10, 1979

[54] TOUCH CONTROL PANEL FOR

INDUCTION HEATING COOK-TOP

[75] Inventor: Raymond M. Tucker, Cleburne, Tex.

[73] Assignee: Rangaire Corporation, Cleburne,
Tex.

[21] Appl. No.: 819,169
[22] Filed: Jul. 26, 1977

[51] Int. CI.2 H05B 5/08; H02B 1/02

[52] U.S. a 361/358; 200/DIG. 1;

219/10.49 R; 219/10.77; 219/506; 340/365 L

[58] Field of Search 219/10.49, 10.77, 10.55 B,

219/445, 459, 453, 492, 493, 490, 494, 497, 499, 501, 506; 307/238, 239, 116, 252 M, 252 K; 323/101; 235/92 EA, 92 EV, 92 DE, 92 CT; 340/337, 365 C, 365 S; 328/48, 71, 5; 363/57, 95, 96, 135; 200/DIG. 1; 361/181, 399, 403,

362, 358, 359

[56] References Cited

U.S. PATENT DOCUMENTS

2,760,123 8/1956 Wills 361/359

3,701,869 10/1972 Jacob et al 340/365 C

3,974,472 8/1976 Gould 219/506

4,001,699 1/1977 Denny et al 328/71

4,045,629 8/1977 Auzani 200/DIG. 1

4,046,991 9/1977 Sefton et al 219/497

The specification discloses a touch control panel particularly adapted for use with an induction heating cooktop. The panel includes a plate of insulating material such as glass having outer and inner planar surfaces separated by a predetermined thickness. Discrete conductive film areas such as tin oxide are formed on the outer planar surface of the plate. A printed circuit board includes a plurality of pairs of spaced apart conductive regions formed of copper or the like thereon. Springs are provided to urge the printed circuit board continually against the inner surface of the plate, such that the pairs of conductive regions are disposed in a predetermined symmetrical orientation below the film areas on the outer surface of the plate. Circuitry is connected on the printed circuit board and is coupled to the conductive regions in order to generate electrical signals in response to contact with the film area by a finger of the operator. By touching various ones of the film areas formed on the plate, the operator can then control the energization and heating level of the induction heating coils located in the cook-top.

16 Claims, 9 Drawing Figures