# US 4,392,618 A · Liquid-projecting monitor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 4,392,618 A - Document ID: US4392618A - Status: Granted - Kind: A - Application number: 06/243,305 - Filed: 1981-03-13 - Granted: 1983-07-12 - Earliest claimed: 1980-03-13 - Assignees: Chubb Fire Security Limited - Inventors: John L. Evans; Kuldip Bains - Web page: https://patentgrep.com/patent/US4392618A ## CPC - F16L 27/087: Joints with radial fluid passages - A62C 31/24: attached to ladders, poles, towers, or other structures with or without rotary heads - B05B 15/654: using universal joints - F16L: PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL - A62C: FIRE-FIGHTING (fire-extinguishing compositions, use of chemical substances in extinguishing fires A62D1/00; spraying, applying liquids or other fluent materials to surfaces in general B05; alarm arrangements G08B, e.g. fire alarms actuated by smoke or gases G08B17/10) - B05B: SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES (spray-mixers with nozzles B01F25/72; processes for applying liquids or other fluent materials to surfaces by spraying B05D) ## Abstract A liquid-projecting monitor of the spherical head type has its head sealing against a housing which defines together with the head a chamber from which liquid is lead into a passage in the head and then to a nozzle coupled to the head. The head is borne by a horizontal axle for pivotal movement relative to the housing so as to adjust the angular elevation or depression of the nozzle. A center body extends transversely across the interior of the head to enclose the axle and is so shaped, together with the internal surface of the head, that the cross-sectional area of the passage within the head available for liquid flow is maintained at least approximately constant throughout its length, so as to minimize the pressure drop in the liquid flow which passes through the head. ## Claims ### Claim 1 A liquid-projecting monitor comprising a housing, and a head for carrying a nozzle; the head having a frusto-spherical external surface and having a passage within the head for liquid flow to the nozzle; the housing defining together with the head a chamber from which liquid is led into said passage within the head and thence to the nozzle; an axle passing transversely through the width of the head to support the head for pivotal movement relative to the housing about a generally horizontal axis so as to provide adjustment of the angular elevation or depression of the head; the frusto-spherical surfce of the head forming a sliding seal against the housing to maintain the aforesaid chamber liquid-tight throughout the permitted range of said pivotal movement; a body extending transversely across the interior of the head to enclose said axle and to define in part the confines of said passage; and the head being so configured that the cross-sectional area of said passage within the head which is available for liquid flow is at least approximately constant throughout the length of said pressure. ### Claim 2 (depends on 1) A monitor according to claim 1 wherein said body is shaped as a streamlined foil pointing upstream in the intended sense of liquid flow through the head. ### Claim 3 (depends on 1) A monitor according to claim 1 wherein the head has an inlet for liquid from said chamber up-stream of said body, the inlet being of generally elliptical cross-section and the internal surface of the head blending smoothly from said generally elliptical form upstream of said body to a generally circular form downstream of said body. ### Claim 4 (depends on 1) A monitor according to claim 1 comprising means for bearing the assembly of said head and housing for pivotal movement as a whole about a generally vertical axis. ### Claim 5 (depends on 4) A monitor according to claim 4 wherein said bearing means include a hollow, generally vertical axle which turns together with said assembly and through which liquid is lead into said chamber. ### Claim 6 (depends on 1) A monitor according to claim 1 wherein said bearing means include an annular chamber surrounding said generally vertical axle for the supply of liquid to the head, the axle having inlet apertures in its wall to permit a flow of liquid from said annular chamber to said first-named chamber defined by said housing and said head. ### Claim 7 A liquid-projecting monitor comprising a housing, and a head for carrying a nozzle; the head having a frusto-spherical external surface and having a passage within the head for liquid flow to the nozzle; the housing defining together with the head a chamber from which liquid is led into said passage wiithin the head and thence to the nozzle; the head being borne for pivotal movement relative to the housing about a generally horizontal axis so as to provide adjustment of the angular elevation or depression of the head; the frusto-spherical surface of the head forming a sliding seal against the housing to maintain the aforesaid chamber liquid-tight throughout the permitted range of said pivotal movement; a hollow, generally vertical axle through which liquid is led into said chamber and by which the assembly of said head and housing is borne for pivotal movement as a whole about a generally vertical axis, said axle turning together with said assembly; and means defining an annular chamber surrounding said axle for the supply of liquid to the head, the axle having inlet apertures in its wall in communication with said annular chamber; and said axle being configured internally to define a circumferentially arrayed series of arcuately extending channels to lead separate streams of liquid smoothly from respective said inlet apertures to the upper portion of the axle. ### Claim 8 (depends on 7) A monitor according to claim 7, comprising support means bearing said generally vertical axle which support means are adapted to be stood upon the ground and have at least one inlet coupling for the supply of liquid to the head via that axle.