GB910839A - Improved apparatus for filling containers with liquid - Google Patents

Abstract

910,839. Fluid-pressure servomotor-control systems. VICKERS RUWOLT PROPRIETARY Ltd. Dec. 29, 1959, No. 44114/59. Class 135. [Also in Group XVII] An apparatus of the rotary turret-type for filling containers 43 with liquid such as beer, includes means for maintaining the air pressure in each container 43, during filling, equal to the gas pressure above a liquid supply in a central distributing tank 22, thereby insuring that the flow of liquid from the distributing tank 22 to each container 43 is due to the hydrostatic pressure only. An air reservoir 21 has a pipe 52 supplying air to each container 43. A differential pressure transmitter 93 is connected to the air reservoir 21 by a pipe 98 and to the gas space above the liquid-distributing tank 22 by a pipe 97. The differential pressure transmitter 93 and a pressure-controlling instrument 92, each receive a uniform controlled air pressure from an air regulator 96, and are interconnected by a pipe 99. When a container 43 reaches its filling position, air flows from the reservoir 21, through pipe 52, into the container, and this causes a momentary decrease in the air pressure in reservoir 21. The resulting pressure difference in pipes 97 and 98 is sensed by the differential pressure transmitter 93 and a pneumatic impulse proportional to this difference is relayed from the transmitter 93, through pipe 99, to the pressure controller 92 which compares the impulse with a set pointer so that a second pneumatic impulse is sent from the controller 92, through pipes 102 and 104 to a vent valve 103 and an air supply valve 91 respectively. This second pneumatic impulse causes a vent valve 103 to close partially or completely, thereby restricting or preventing further escape of air from the reservoir 21 through this vent, and also permits more air to be admitted through the supply valve 91 with the result that the pressure inside the air reservoir 21 increases to the required value. When the container 43 starts to fill, the air pressure in the container increases and back pressure occurs along pipe line 52, to the reservoir 21 to cause a pressure difference in pipes 97 and 98. This difference causes the valve 103 to open partially or completely to exhaust air from the reservoir 21 and caused valve 91 to close partially or completely to restrict or prevent the entrance of air to the reservoir 21.