Safety pilot enclosure having flame-diverting air inlet

Claim 1

For use with gas-fired furnaces and like appliances wherein a safety pilot both ignites the gas from a main burner orifice and provides heat to a thermocouple which controls a shut-off valve to such main burner, a safety pilot comprising a thermocouple supported substantially vertically, pilot gas supply means including a substantially vertical orifice for gas only, the orifice being spaced from the thermocouple in a substantially vertical plane, and a metal flame-developing hood positioned slantingly above the pilot gas orifice and having downward-flanged edges tapering wideningly outward from a central hood indentation, whereby to develop a two-tongued forked flame, the hood being positioned at such angle to such vertical plane that one of the hood edges directs a tongue of such flame toward the thermocouple and the other edge extends angularly outward, characterized in having a sheet metal enclosure having substantially vertical side walls, whereby to shield such pilot orifice and at least the lower portions of the hood and thermocouple from horizontal air flow, one of said side walls extending between the pilot orifice and such main burner and its upper portion being presented beneath such angularly outward extending edge of the hood, further characterized in that a horizontal air flow opening extends through that side wall of the enclosure which is adjacent to the thermocouple and remote from the pilot gas orifice, whereby, if the pilot flame height lowers, inflow of air into the enclosure through said horizontal air flow opening will divert a portion of the flame from that tongue which extends toward the thermocouple to the other tongue which extends over that side wall of the enclosure separating the pilot flame from the main burner, thereby to prefer ignition of the main burner over voltage output from the thermocouple.