A method of manufacturing an inkjet head includes forming a plurality of electrodes at predetermined positions on an upside of a base piezoelectric layer. The power source has a main air-intake passage fluidly connected to a first air-intake passage and a second air-intake passage. With the gelated electrolyte composed of the polyacrylonitrile containing high molecular material, non-aqueous solvent and the electrolyte salt mainly composed of LiPF6, a carbide film is formed on the electrode surface, on contact with the flame, as a result of the carbonization of the high molecular material and the carbonization accelerating operation of LiPF6. Adjacent to each tooth in a circumferential direction at least one gap is provided, into which gap of one coupling half a tooth of the other coupling half enters and fits, and each tooth is equipped in the circumferential direction with a bevel.