PROBLEM TO BE SOLVED: To provide a nozzle of which atomization function and clog prevention function are improved.SOLUTION: A nozzle comprises a nozzle body and a closer which is accommodated in the nozzle body, in which the nozzle body comprises an ejection side wall at a center of which an ejection hole penetrates, and an outer peripheral wall, and the closer is accommodated in a space surrounded by the ejection side wall and an inner peripheral surface of the outer peripheral wall of the nozzle body. A large diameter inflow port of the ejection hole of the nozzle body is provided on a central part of an inflow side inner face of the ejection side wall or a central part of an ejection side end face of the closer. An inner peripheral end of an arc-shaped revolving groove, which is provided on an outer peripheral step part surrounding the large diameter inflow port, is opened to the large diameter inflow port, and an outer peripheral end of the revolving groove is opened to a liquid passage provided on an outer periphery of the closer so that a revolving flow, which flows in the revolving groove, is ejected from the ejection hole. An inside end of the revolving groove is provided with an orifice having a width and a depth of a dimension L1, and the dimension L1 is so made as to be equal to a dimension of a minimum diameter portion of the ejection hole.SELECTED DRAWING: Figure 1【課題】微粒化機能と目詰まり防止機能を向上させたノズルを提供する。【解決手段】ノズル本体と、該ノズル本体に収容するクローザーを備え、前記ノズル本体は中央に噴射穴が貫通した噴射側壁と外周壁を備え、該ノズル本体の噴射側壁と外周壁の内周面に囲まれた空間に前記クローザーが収容されており、前記ノズル本体の噴射穴の大径流入口は前記噴射側壁の流入側内面の中央部分または前記クローザーの噴射側端面の中央部分に設けられ、該大径流入口を囲む外周段部に設けられる円弧状の旋回溝の内周端が前記大径流入口に開口すると共に、前記旋回溝の外周端を該クローザーの外周に設けられる液通路に開口させて前記旋回溝を流れる旋回流が前記噴射穴より噴霧されるものとし、かつ、前記旋回溝の内側端に寸法Ｌ１の幅と深さを有するオリフィスを備え、前記寸法Ｌ１は前記噴射穴の最小径部分の寸法と同等とされている。【選択図】図１
