Flat electric heater, e.g. food warming plate - has sandwich of polymeric concrete slab with natural stone slab and zigzag flexible conductor between them

摘要

The flat heater containing a zigzag flexible electrical conductor (2) is made in the form of a monolithic sandwich enveloping the conductor, using a casting, press or injection moulding method. The two layers comprise artificial stone like polymeric concrete (1) and a natural stone slab (20). The artificial stone slab has a recess in a corner away a little from the conductor where a thermostat (4) is positioned, but not in direct thermal contact with the stone. This same slab has integral mounting brackets on its rear surface. On the conductor side, there is a grid-like frame (also made of polymeric concrete) with pegs around which the conductor is hooked. ADVANTAGE - Easily manufactured and with a high thermal capacity.