PURPOSE: To prevent deformation at the opening end part, and to reliably seal the mount to the bulb in such a way that flame holes of a burner mechanism are inclined by specified angles to the axial center line of the exhaust pipe of the mount from the outside toward the flare part outer peripheral end and the bulb opening end part into which the mount is inserted.

CONSTITUTION: A mount holder 10 is incorporatively penetrated and fixed in the central part of an enclosing head body 9, and this holder 10 positions the flare part in such a way that a tapered tip part 10a is tucked to meet the inside of the flare part 103 of a mount 101. Furthermore, a ring-shaped sealing burner 17 is provided in front of the head body 9, and this burner 17 has flame holes 18 to make for the outer peripheral end of the flare part 103. Besides, these flame holes 18 have their inclined angles θ to the axial center line of the exhaust pipe 102, namely the axial center of the inserting hole 13 set within the range of 50°W80°. This facilitates to prevent deformation at the opening end part of the valve, and to reliably seal the bulb to the mount.