EP 0335617 A3 19910320 - CURRENT SOURCE LIMITATION FOR THICK FILM HEATING ELEMENTS

Title (en)

CURRENT SOURCE LIMITATION FOR THICK FILM HEATING ELEMENTS

Publication

EP 0335617 A3 19910320 (EN)

Application

EP 89302961 A 19890323

Priority

GB 8807139 A 19880325

Abstract (en)

[origin: EP0335617A2] A heating element (1) comprises a plurality of thick film electrically resistive tracks (2, 4, 6), of which at least one has a temperature coefficient of resistance in excess of 0.006 per degree C. A first track (2) is for electrical connection to a power supply. Means (12, 14) for electrically connecting the first track (2) to a second track (4, 6) comprise a component which depends on temperature such that, in use, the current flowing in the second track (4, 6) increases with the temperature of the first track (2).

IPC 1-7

H05B 3/26; H05B 3/74

IPC 8 full level

H05B 3/26 (2006.01); H05B 3/74 (2006.01)

CPC (source: EP)

H05B 3/26 (2013.01); H05B 3/748 (2013.01); H05B 2203/002 (2013.01); H05B 2203/005 (2013.01); H05B 2203/013 (2013.01); H05B 2203/017 (2013.01); H05B 2203/019 (2013.01)

Citation (search report)

[A] EP 0227405 A2 19870701 - RAYCHEM CORP [US]
[A] EP 0208823 A1 19870121 - KANTHAL AB [SE]
[A] US 3396055 A 19680806 - HEDDEN WALTER A, et al
[A] US 2777930 A 19570115 - MAX NATHANSON

Designated contracting state (EPC)

AT BE CH DE ES FR GB GR IT LI LU NL SE

DOCDB simple family (publication)

EP 0335617 A2 19891004; EP 0335617 A3 19910320; EP 0335617 B1 19931201; AT E98082 T1 19931215; DE 68911008 D1 19940113; DE 68911008 T2 19940616; GB 8807139 D0 19880427

DOCDB simple family (application)

EP 89302961 A 19890323; AT 89302961 T 19890323; DE 68911008 T 19890323; GB 8807139 A 19880325