Zone-regulated high-temperature electric-heating system for the manufacture of products made from composite materials

Claim 1

High temperature electrical heater equipment for mounting n a rigid mechanical support (66), the equipment being of the type comprising: a heat-distribution plate (60) at a distance from said mechanical support (66); thermal insulation means (65) provided against said mechanical support (66) and on the lateral margins of said equipment; electrical heater means and cooling means disposed between said heat-distribution plate (60) and said thermal insulation means (65); and temperature regulation means for maintaining a uniform temperature over the entire area of said temperature distribution plate (60) as a function of a manufacturing program; the equipment being characterized in that: a) the said electrical heater means and the said cooling means are disposed in independent layers between said thermal insulation means (65) and said heat-distribution plate (60); b) the electrical heater means comprise a heater submodule (61) situated adjacent to said heat-distribution plate (60) and a heat return plate (64) fixed to said heater submodule (61) on the opposite side to said heat-distribution plate (60); c) the heater submodule (61) includes a plurality of flat and solid metal-clad heater elements (62) disposed across the width of the said heat-distribution plate (60) and spaced apart by spacer blocks (63); d) each heater element (62) includes at least three electrical resistances (X1, X2, X3) which are separate from one another and distributed in the lengthwise direction of the element; e) the heater elements (62) are distributed along the length of said heat-distribution plate (60) in at least three zones, thereby defining at least nine different juxtaposed and joining heater zones (Z1, . . . , Z9) by virtue of the electrical resistances (X1, X2, X3) being distributed across the width of said heat distribution plate (60); f) the heat-distribution plate (60) includes a temperature sensor (TC) in each heater zone (Z1, . . . , Z9) and g) the electrical resistances in each zone are electrically powered independently from the electrical resistances in the other heater zones via electronic power feed means for each zone, and as a function of predetermined references for each heater zone co-operating with said temperature sensors, said power feed means for each zone being regulated by a PID regulator.