Abstract: A portable electric hotplate is heated by an inductive heating power source having a glass ceramic plate and a primary induction coil. The hotplate has an outer heat conductive casing, the top of which forms a hotplate and the base of which is made from a dielectric material. The top surface of the hotplate is heated by an electrical resistor embedded therein adjacent the top surface, which resistor is connector to a secondary inductive circuit mounted adjacent the dielectric base of the hotplate. The hotplate secondary circuit has an induction coil which serves as the secondary for the electromagnetic field emitted by the primary induction coil in the heating power source. The secondary coil is connected in parallel with a capacitor and the two are connected in series to the electrical resistor embedded in the top surface of the hotplate.

Abstract: Induction-heated hob or cookplate has a glass-ceramic transparent top plate, one or more inductor coils below the top plate, and a support plate that has cutout or cutouts in which the inductor coil or coils are situated. The inductor coil or coils is in the form of a spiral or flat winding or a square or rectangular flat winding. A converter receives household power (e.g. 220 v, 60 Hz) and provides an alternating current of suitable frequency (e.g. 25 KHz to 30 KHz) to the inductor coils. Between the support plate and the top plate there is an intermediate complex composed, e.g., of a mica sheet and a glass fabric sheet. Markings or decoration are disposed on the underside of the top plate or on the glass fabric sheet, where they are clearly visible through the transparent top plate, but are not subject to abrasion from cooking utensils or scrubbing.