| 摘要 |
PROBLEM TO BE SOLVED: To provide a rich/lean combustion burner capable of unifying a supply flow rate of rich air-fuel mixture over all longitudinal direction regions when rich air-fuel mixture in a rich air-fuel mixture introduction passage is introduced into a rich air-fuel mixture supply passage from a communication hole at a longitudinal direction intermediate position and the rich air-fuel mixture is supplied to a central rich flame hole.SOLUTION: Rich flame holes 331 at a central rich burner part 3a, lean flame holes of lean burner parts at both sides and rich flame holes of outer rich burners at both outer sides are arrayed in order. A lower end part 60a of the central rich burner part is protruded to open a first communication hole 61 in relation to the inside of a cylinder part 38 into which rich air-fuel mixture is introduced in a right direction. A rich air-fuel mixture diffusion part 657 is provided at an upper position of the first communication hole to diffuse the rich air-fuel mixture introduced upward from the first communication hole to both of right and left sides. Restriction parts 658 for flow rate stabilization are provided at lower side positions of the rich flame holes in the right side region, and a flow path expansion part 654 is provided in the longitudinal direction between the restriction parts and the rich flame holes to unify supply flow rate. |
