Container filling machine

A machine for filling with liquid containers having spring-loaded closure units, the filling being carried out via a head which seals with a container to be filled and which carries means to open the closure unit of said container, the machine comprising:

• a main frame and a filling head movable relative to the frame to engage a container to be filled,
• a liquid inlet valve on the frame and a conduit from the liquid inlet valve to a change-over valve fixed to the head,
• a liquid outlet valve on the frame and a conduit from the liquid outlet valve to the change-over valve,
• a gas inlet valve fixed on the frame and a conduit from the gas inlet valve to the head,
• said change-over valve being operable in synchronism with the liquid inlet valve,
• the change-over valve being adjustable to a first state in which the head communicates with the liquid inlet valve and a second state in which the head communicates wih the liquid outlet valve, and,
• control means arranged so that during filling of a container the container closure unit is open, the liquid inlet valve is open and the change-over valve is in its first state so that liquid passes through the liquid inlet valve and the conduit from it to the change-over valve, then to the head and then into the container and, upon termination of filling, the container closure unit and the liquid inlet valve are closed, the change-over valve is changed over to its second state and the gas inlet valve is opened so that gas can flow from the gas inlet valve through the conduit from it to the head to enable the gas to clear the head of liquid which is driven by the gas through the change-over valve into the conduit therefrom to the liquid outlet valve.