GB1274495A - Fluid medium dispensing apparatus - Google Patents

Abstract

1,274,495. Portable pressurised fire extinguishers. WALTER KIDDE & CO. 11 Aug., 1969 [18 Sept., 1968; 20 Sept., 1968], No. 40128/69. Heading A5A. Apparatus for dispensing a fluid medium under pressure, particularly water or a dry powder fire extinguishant, comprises a container therefor (e.g. 10, Fig. 1), a neck opening closable by a control head, 12, which is movable between an outer operational position sealing the opening and an inner venting position, a pressure surface 41 subject to the internal fluid pressure tending to urge head 12 outwards, sealing means connected to 12 and cooperating with neck 11 to seal the opening when 12 is in the outer position but ineffective in the inner position, and disengageable locking means including pin 16 which limits outward movement of 12 to the outer position and is disengageable on movement to the inner position. Metal container 10 and neck 11 are welded together and closed by plastic control head 12 formed with stepped portions 21, 22, upper part 23, axial bore 24 for syphon tube 15, and discharge passageway 25. Syphon tube 15 is controlled by valve 14. Handle 38 and valveoperating lever 39 are rigidly-pivotally mounted respectively such that valve 14 is operated by squeezing 38 and 39 together. Seal arrangement 13 includes annular formation 40 at the base of neck 11 providing cylindrical surface 41 against which acts "O" ring seal 42 mounted in annular recess 48 in step 22. The diameters of 21, 22 and 11, 40 are such as to provide a vent passageway from the container interior to atmosphere when control head 12 is depressed, shoulder 43 limiting the extent of depression. In Figs. 1-3 the locking means includes U- shaped pin 16 a pair of diametrically opposite vertical slots 44, 45 in control head part 20 and similar slots 46, 47 and 49, 50 in neck 11 aligned with 44 and 45 respectively. The pin arms 51, 52 extend through 44-46-47, and 45-49-50, and are bent where they emerge from neck 11 to form obstructing sections 55, 56 which prevent withdrawal of the pin. The slots are arranged to be in alignment for pin withdrawal only when 'O' ring 42 is below surface 41. Normal container pressure urges head 12 upwardly such that the bottom surfaces of slots 44, 45 engage arms 51, 52 and lift the pin until it engages the upper surfaces of slots 46, 47, 49, 50, in which position 'O' ring 42 engages surface 41 to form a gastight seal. As long as the container remains pressurised pin 16 cannot be withdrawn. To refill or service the container, head 12 is manually depressed to align the head and neck slots and to break the seal. The container thus vents to atmosphere and pin 16 can be withdrawn to release the head for removal. The force required to depress the head indicates the residual pressure in the container, and valve 14 is operated as necessary to discharge fully before disassembly. In Figs. 4-7 a modified locking clip is shown.