主权项 |
1. A rich-lean combustion burner with one row of central rich-side flame holes longitudinally-aligned, two rows of lean-side flame holes aligned on outer sides of said one row of central rich-side flame holes, two rows of outer rich-side flame holes aligned on outer sides of said two rows of lean-side flame holes, said one row of central rich-side flame holes on which rich-side flames generated using a rich-side mixture supplied thereto through a rich-side mixture supply channel, and said two rows of lean-side flame holes on which lean-side flames generated using a lean-side mixture supplied thereto through a lean-side mixture supply channel, said rich-lean combustion burner comprising:
an inner plate member comprising a pair of plate parts facing each other, a bent part integrally connecting said plate parts at lower end thereof and an upper end opening, each of said plate parts having both longitudinal side edges, said inner plate member formed by bending the center of a single sheet of plate material so as to form said pair of plate parts and said bent part; a pair of outer plate members which a predetermined clearance gap is formed therebetween, with slit parts provided at both longitudinal side edges of said pair of outer plate members, each of said slit parts having an inner width corresponding to the thickness of said side edges of said inner plate member and opening upward; and a pair of outermost plate members which is placed on the outside of said pair of outer plate members so as to form a predetermined clearance gap therebetween with opening at its upper end, wherein said one row of central rich-side flame holes is defined by said upper end opening of said inner plate member, wherein said two rows of lean-side flame holes are defined between both outer faces of said inner plate member and both inner faces of said pair of outer plate members, wherein said two rows of outer rich-side frame holes are defined between both outer faces of said pair of outer plate members and both inner faces of said pair of outermost plate members, wherein said inner plate member is assembled in said clearance gap between said outer plate members, with said side edges of said inner plate member pinched in said slit parts so as to close contact each other, whereby said rich-side mixture supply channel is defined between opposing surfaces of said pair of plate parts, and wherein said bent part of said inner plate member is exposedly disposed vertically halfway in said lean-side mixture supply channel partitioned and formed between said opposing surfaces of said pair of outer plate member, whereby said lean-side mixture supply channel is divided by said bent part of said inner plate member to provide separate extensions to said two rows of lean-side flame holes. |