GB872187A - Metering valves for pressurised containers - Google Patents

Abstract

872,187. Dispensing measured quantities of liquids. RISDON MANUFACTURING CO. Oct. 1, 1959 [Nov. 10, 1958], No. 33271/59. Class 106(5) [Also in Group XXVIII] - A device for dispensing measured quantities of liquid from a pressurized container 22 comprises a measuring chamber 50 formed in a valve housing 34 having intake and discharge ports 72, 56 for connecting the chamber with the interior of the container and with atmosphere respectively, valve means 70, 62 associated with each port, and a closed auxiliary chamber mounted on the housing and in continuously open communication with the chamber intermediate both ports. The valve housing 34, of a suitable moulded plastic material, has a flange 36 sealingly clamped by a cap 38 against a flange 40 formed on a resilient sack 42, the interior of which, together with the exterior of the valve housing and a dip tube 32 secured thereto, defines the auxiliary chamber 80. A hollow valve plunger 52 passes into the chamber 50 through a sealing ring 60 and is arranged at its lower end, to co-operate with an elastomeric valve plug 70. In operation, liquid in the container, which is pressurized by a gas, such as nitrogen, in the space 30 above the liquid, is forced by the gas up the tube 32 through the inlet space 72 into the chamber 50 and thence through a number of ports 82 into the chamber 80, escape of the liquid from the container being prevented by a ridge 54 on the plunger engaging a resilient sealing washer 62. Upon depression of a nozzle 26 secured to the plunger 52, the latter acts against the valve plug 70 so as to close off the inlet space 72 and, after further depression, bring the port 56 in the plunger into communication with the chamber 50, the liquid in the chamber 80 then being dispensed due to the collapse of the resilient sack under the action of the gas pressure in the space 30; in the case when the propellant gas readily mixes with the liquid being dispensed, the admixture contained in the chamber 50 is also dispensed under the action of the gas contained therein. The container is filled by removing the nozzle 26, fitting a filling head over the end of the valve plunger 52, depressing the plunger so as to bring the ports 56 into communication with the chamber 50, then forcing the liquid under pressure through the ports 56 into the chamber 80 thereby lifting a sealing lip 43 out of contact with the dip tube 32 so that the liquid may enter the container (Fig. 5, not shown). Fig. 6 shows, inter alia, a modified form of the nozzle 166 and method of clamping the valve housing 116 and resilient sack 154 to the container 112, the flexible lip 160 of the sack engaging an extension of the valve housing; the function of the device is identical with that previously described. Specification 798,169 is referred to.