Electric heater using light bulbs as heat source - uses array of light bulbs in light-tight but not air tight box with bulbs series connected to run at half nominal voltage

摘要

The appts. uses an array of light bulbs in an enclosure to provide heat, and electric motor driven fans to circulate air through the light bulb array. The enclosure has a labyrinth air exit to allow air flow while masking the light output To improve bulb life, the bulbs are wired in series groups so that they operate at half their nominal operating voltage for 15 watt bulbs, decreasing with increasing power rating to round 25 per cent of normal voltage for 60 watt bulbs. The bulbs used are the spherical type E14 with either a zig-zag filament or a crown filament.