To always realize a stable double-staged combustion and further enable a low NOx combustion to be carried out.
There are provided a Bunsen burner main body 1 having a primary flame hole 2 at its upper surface and a combustion chamber 4 having a box-like combustion chamber wall 3 substantially air-tightly enclosing a circumference of the primary flame hole 2. The combustion chamber 4 is formed into such a shape as one in which it has a stepped part with its upper part being wide and lower part being narrow in a longitudinal direction of the primary flame hole 2. The upper surface of the combustion chamber wall 3 is provided with a secondary flame hole 20, a partition plate having an auxiliary flame hole 5 arranged to divide the combustion chamber 4 into an upper segment and a lower segment in a vertical direction holds an auxiliary combustion chamber 27 and then the flame formed at the primary flame hole 2 and auxiliary flame hole 5 is shut off with secondary air to restrict occurrence of NOx.
MORIHANA HIDEAKI
ISHIKURA NAOKI
