| 摘要 |
PURPOSE:To reduce a machining expenses by machining the outer peripheral wall of a hollow protrusion formed on the upper surface of a burner cap, and forming a lid member at the upper part of a cylindrical part through a clearance except a protruding part provided on the hollow inner surface of the burner. CONSTITUTION:The size phiB of a hollow part 18 of a protrusion 17 is formed at a protruding part 20 and a tip end except a material corresponding to a lid member 6. When machining of an outer peripheral wall 21 is carried out up to a size phiD by use of a lathe or the like, since the size phiD is smaller in the diameter than the size phiB, a gap 5 intermittent by the protruding part 20 is formed between the lid member 6 and an upper end part 8. Therefore, a cylindrical part 4 and the lid member 6 constituting a burner cap 2 are formed into an integral body. Further, since a gap 5 is formed, the machining for providing the gap 5 is made by one machining work by a lathe or the like. Further, by selecting the relation between the sizes of respective parts to phiA>phiB>phiD>phiC, where phiA represents the size of the protrusion 17, and phiC, the size of the protruded part 20, the burner cap 2 and the lid member 6 can be simultaneously formed integrally by forging, casting or the like. |
