INDUCTION DEVICE COMPRISING MULTIPLE INDIVIDUAL COILS FOR INDUCTION HEATING PLATES
An induction device for an induction heating plate ( 5 ), is adapted in such a way as to be arranged beneath a vitroceramic plate and includes at least first and second individual electroconductive windings ( 3 A and 3 B) which are arranged next to each other in a first plane. The device includes a magnetic conductive element ( 6 ) forming a coupling member which extends beneath the first individual winding ( 3 A) and the second individual winding ( 3 B) in such a way as to magnetically couple the first and second individual windings ( 3 A and 3 B). The invention can be especially used in an induction cooking surface.
1 . Induction device for an induction heating plate designed to be positioned under a glass-ceramic plate ( 1 ), comprising at least first and second individual coils ( 3 A and 3 B) with electrically conductive windings, positioned side by side in a first plane, characterized in that it comprises a magnetic conductive element ( 6 ) forming coupling means extending below the first individual coil ( 3 A) and below the second individual coil ( 3 B) so as to magnetically couple said first and second individual coils ( 3 A and 3 B).
2 . Device according to claim 1 , characterized in that the magnetic conductive element ( 6 ) is a one-piece element.
3 . Device according to claim 1 , characterized in that the magnetic conductive element ( 6 ) is split into two parts ( 6 A, 6 B) separated by an airgap (E).
4 . Device according to claim 3 , characterized in that the airgap (E) is less than or equal to 5 mm.
5 . Device according to claim 3 , characterized in that the two parts ( 6 A and 6 B) of the magnetic conductive element extend beyond the first and second individual coils ( 3 A and 3 B) respectively.
6 . Device according to claim 1 , characterized in that the magnetic conductive element ( 6 ; 6 ′) extends in a direction (D) coincident with an axis (X) passing through the centers of said first and second coils ( 3 A, 3 B; 3 B, 3 C).
7 . Device according to claim 1 , characterized in that the magnetic conductive element ( 6 ; 6 ′) extends in a direction (D) shifted relative to the axis (X) passing through the centers of said first and second coils ( 3 A, 3 B; 3 B, 3 C).
8 . Device according to claim 1 , characterized in that the portion of surface (S 1 ; S 1 ′) of the magnetic conductive element ( 6 ; 6 ′) covered by the first coil ( 3 B) is less than the portion of surface (S 2 ; S 2 ′) of the magnetic conductive element ( 6 ; 6 ′) covered by the second coil ( 3 A; 3 C).
9 . Device according to claim 1 , characterized in that the dimensions of the first coil ( 3 B) are greater than the dimensions of the second coil ( 3 A).
10 . Device according to claim 1 , characterized in that it comprises at least a third coil ( 3 C) and at least a second magnetic conductive element ( 6 ′) forming coupling means extending below the first coil ( 3 B) and below the third coil ( 3 C).
11 . Device according to claim 1 , characterized in that the electrically conductive windings of the individual coils ( 3 A, 3 B) are not parallel to each other.
12 . Device according to claim 1 , characterized in that the first and second individual coils ( 3 A, 3 B) are biased in opposite directions.
13 . Device according to claim 1 , characterized in that the first and second individual coils ( 3 A, 3 B) are connected in series.
14 . Device according to claim 1 , characterized in that the first and second individual coils ( 3 A, 3 B) each extend in a disk.
15 . Device according to claim 1 , characterized in that the material of the magnetic conductive element(s) ( 6 , 6 ′) forming coupling means is a ferrite.
16 . Induction hob comprising at least one heating plate ( 5 ) and a glass-ceramic plate ( 1 ), characterized in that it comprises an induction device claim 1 associated with said heating plate.
17 . Device according to claim 4 , characterized in that the two parts ( 6 A and 6 B) of the magnetic conductive element extend beyond the first and second individual coils ( 3 A and 3 B) respectively.