Liquid filling and level sensing apparatus

Abstract

Container filling apparatus having a novel, multi-purpose nozzle including a valve designed to control injection of a liquid or semi-liquid product into the container and a further means for evacuating any froth or foam from the container while simultaneously sensing when the level of product within the container reaches the predetermined full level. The valve comprises a hollow cylindrical body defining a chamber for receiving froth and foam and discharging same through a drain port. Passing longitudinally through this body member is a tubular piston having a product tube portion extending therefrom and dimensioned to fit through the neck of the container to be filled. The product tube has an exit port near its distal end and surrounding the product tube is a combination venting and level sensing tube. The space between the outside of the product tube and the inside of the venting/level sensing tube communicates with the froth/foam receiving chamber in the valve body. Means are provided for coupling this same clearance space to a fluidic logic controller. When a container to be filled is positioned with the coaxial tube arrangement entering the filling neck thereof, the exit port zone of the product tube is extended outwardly from the distal end of the venting/level sensing tube, thereby unblocking the exit ports allowing the liquid product to flow into the container. As froth or foam flows up the venting/level sensing tube to the drain chamber, the pressure in this tube is continuously sensed. When the product level reaches the open end of the venting/sensing tube, a sudden pressure change is detected which triggers the fluidic control unit, causing the tubular piston to be retracted, terminating the product flow.