Abstract: A fluid discharge nozzle includes a nozzle tip defining a spout for jetting fluid at a jet angle. Wall surfaces surround the spout and extend downstream with respect to a jetting direction. The wall surfaces contact free surfaces of the fluid jetting out of the spout. Fluid jets produce negative pressure regions inwardly of a forward end surface of the nozzle tip.

Abstract: The present invention relates to a descaling nozzle for removing scales from a metal surface by causing a high-pressure liquid to collide with the metal surface. In the descaling nozzle, the nozzle body includes a concave section formed at a forward end thereof with respect to a liquid jetting direction and having a diameter reducing as it extends downstream with respect to the liquid jetting direction. The forward end has an annular shape integrally surrounding an entire outer circumference of said concave section. The orifice has an outlet opening at a bottom of said concave section around an entire circumference thereof. Thus, the orifice peripheries have high wear resistance against ultrahigh-pressure water and have durability, and can be effectively prevented from damage.

Abstract: A fluid jet nozzle apparatus includes a fluid passage communicated with a fluid jet opening, a valve member for opening/closing the fluid passage, and an elastic member for biasing and moving the valve member to a passage closing position. The valve member includes a pressure receiving face for moving the valve member to a passage opening position against the biasing force of the elastic member in response to application thereto of a fluid pressure exceeding a predetermined pressure. The valve member and the elastic member are interposed between an entrance opening of the fluid passage and a strainer surrounding the entrance opening.

Abstract: A liquid-spraying nozzle has a bottom-equipped nozzle body which includes an inner peripheral face formed at an inner bottom portion of the body and coaxial or substantially coaxial with a nozzle axis and a laterally-elongated orifice defined normal or substantially normal to the nozzle axis when viewed from the direction of the nozzle axis. The invention is characterized by a large-diameter peripheral face formed upstream of the inner peripheral face and having a larger inner diameter than the inner peripheral face, a stepped portion formed between the inner peripheral face and the large-diameter peripheral face, and a pair of elongated grooves disposed along the nozzle axis and at positions opposing to each other across a longitudinal center of the orifice of the inner peripheral face. Each elongated groove has a downstream end relative to the spraying direction with an arcuate cross section extending to the vicinity of the orifice and an upstream end opened at the stepped portion.

Abstract: A descaling nozzle having a straightening passage incorporating a straightener, a constricted passage communicating with a downstream side of the straightening passage and a jetting passage communicating with a dowstream side of the constricted passage. The jetting passage has a jetting opening at a bottom of a groove defined at a top end face thereof in the direction of diameter of the same. Axes of the straightening, constricted and jetting passages are aligned on the same straight line. The straightening passage has the same radius through its whole or substantially whole length and the constricted passage has a radius tapering from its upstream end to its downstream end or to a vicinity of the same.

Abstract: There is disclosed a nozzle apparatus for spraying a mixture of gas and liquid. The apparatus comprises a casing having therein a gas jetting nozzle member and a liquid chamber. The liquid flows out of the chamber in directions to cross at a predetermined angle with a direction in which the gas is jetted out of the nozzle member.