METHOD OF PRODUCTION OF FLEXIBLE COMPOSITE ELECTRIC HEATER Russian patent published in 1997 - IPC

FIELD: electrical engineering, in particular technique of production of resistive heating elements, can be used in production of electric heaters for spot heating in technical and domestic conditions. SUBSTANCE: method of production of flexible composite electric heater consists in production of current- conducting and insulating layers from composite material based on butyl rubber, laying of two electrodes of metal gauze with flexible current leads at the edges of the current-conducting layer, placement of the current-conducting layer with electrodes and flexible current leads between the insulating layers and subsequent vulcanization of the assembled pack. Prior to laying of the current-conducting layer with electrodes between the insulating layers, an additional layer of material of the current-conducting layer is put from the top on each electrode. The flexible current leads between the insulating layers are laid in the form of a wavy line. Vulcanization of the assembled pack is carried out in two stages; in the first stage, during 10 to 15 min, a pressure of 14 to 16 MPa is built up, and in the second stage, during 30 to 35 min, a pressure of 3 to 5 MPa is built up. This ensures a uniform distribution of electric field strength in electric heaters and, hence, a uniform heat release over the entire surface, reduction of the number of defective products due to prevention of breaks of connection of current leads and electrodes, considerable reduction of process power intensity. EFFECT: enhanced quality. 2 cl, 1 dwg