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

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.