Temperature controllable heater plate for molds

Claim 1

A heater plate assembly for a plunger-type molding press, said heater plate assembly comprising: a heater plate having upper and lower surfaces and a peripheral edge, said plate having a center, said plate being provided with a plurality of holes extending into the plate perpendicularly to the top and bottom surfaces, said holes being disposed in a plurality of spaced rows extending parallel to the peripheral edge of the plate and of successively increasing distance from the center of the plate to divide the plate into a plurality of regions constituting congruent partial areas of the surfaces of the plate, a corresponding plurality of selectively electrically heatable heating members, each disposed in one of said holes thereby dividing the body of the plate into a plurality of heatable areas of the heater plate, the spacing between successive rows of holes and heating members therein progressively decreasing from the center of said heater plate toward the peripheral edge of said heater plate, thereby increasing the density of the heating members from the center of the plate towards the peripheral edge, and control means for individually controlling the heating of the heating members and thus of the temperatures in said heatable areas.