GB1350209A - Counterpressure filling machine - Google Patents

Abstract

1350209 Counterpressure filling machine DAWSON & BARFOS Ltd 27 Oct 1971 [4 Nov 1970] 52408/70 Heading B8T A counterpressure filling machine is operated by pneumatic low and high pressure systems; the low pressure system controls a snift valve 172 and pilot valve 148, and the high pressure system, controlled by the pilot valve 148, operates the counterpressure valve 70 and liquid valve 50. With no container 216 below the bell 208, the button 180 is depressed by a cam (194), Fig. 1 (not shown), and held by a spring limb 192, and the low pressure system in tubes 162 and 168 is vented to atmosphere through an opening (184), Fig. 3 (not shown), the venting allowing the diaphragm 158 to remain undisplaced. The pipe 152 then supplies high pressure air to a chamber above the main piston 110, which is forced down and shuts the counterpressure and liquid valves 70 and 50 respectively. As the bell 208 is raised by a container top, the spring 192 disengages from the button 180 thus closing the opening (184) and causing a pressure build up in the low pressure system which causes the diaphragm 158 to be displaced, thus shutting off the high pressure pipe 152 from the chamber above piston 110 which is now vented to the atmosphere through vent 160. This allows piston 110 to rise under the action of the spring 120 and open the counterpressure valve 70 which pressurizes the container through the counterpressure tube 60 and eye 56. The spring 66 and pressure build up in the container cause the liquid valve 50 to move upwards and allow liquid 222 to fill the container. During filling air is forced through port 134 and between the pistons 110 and 114, separating them and thus reducing the counterpressure valve opening, Fig. 7 (not shown), and allowing rapid closure if bottle breakage occurs. After a predetermined time, the cam (194) again engages button 180 causing the low pressure system to be vented, and the high pressure system to force piston 110 down and close the counterpressure and liquid valves. Excess pressure in the container 216 is vented to the atmosphere by forcing the valve member (196), Fig. 3 (not shown), away from the snift passage (200).