GB817823A - Improvements in and relating to apparatus for filling containers with liquid - Google Patents

Abstract

817,823. Automatic pressure control systems. MEYER LIQUID Ltd., and FRIENDSHIP, K. F. M. Feb. 5, 1958 [Feb. 6, 1957], No. 4047/57. Class 38 (4). [Also in Group XVII] In a counter pressure bottle-filling machine a column of liquid is balanced against the pressure in the filling-tank 1 and the pressure in a vessel 15 for counter-pressure fluid, and changes in level of the liquid are detected and utilized through suitable relay or transducer means to control the pressure in vessel 15. Liquid is supplied to filling-tank 1 through pipe 2 and the level is maintained constant through a device 6 as described in Specification 631,610. Air under pressure is supplied to tank 1 through pipe 13 and control 12 from a supply line 8. Counter pressure is supplied to a ring main 22 through line 21 fed from vessel 15 which is connected to line 8 through a three-way valve 17 including a vent 19. A U-tube containing a liquid such as oil has one limb 23 in communication with line 13 feeding the liquid tank 1, while the other limb 24 communicates with the pressure vessel 15. A detector 27, e.g. a photoelectric cell in conjunction with a light source or a radio-active isotope in conjunction with a Geiger-Muller rate meter or an ionization chamber, senses a rise in level of liquid in limb 24 due to a fall in counter pressure and causes operation of a relay 28 operating three-way switch 17 which opens to allow counter pressure fluid to enter through line 16. If counter pressure becomes too great the vessel 15 is vented to atmosphere. The U-tube may be replaced by a single column of liquid, the upper end of which is in communication with a diaphragm or other displaceable member subject to filling tank pressure. A balanced relay or transducer system is attached to the diaphragm to control the pressure of vessel 15. Specifications 541,200, 650,454, 790,506 and 817,824, [all in Group XVII], are referred to.