Plastics material components metering device - has rotary valve with outlet port provided with groove providing recirculatory path on rotation of valve

摘要

Metering device for mixers used in the mfr. of plastics materials contg. several components has a housing which is fitted with a sealing bushing in which is disposed a rotary valve. Valve is hollow and provided with component inlet duct and a component outlet duct. Duct is associated with a peripheral groove which is arranged to interconnect the outlet duct and the sealing duct with a flushing channel when the valve is rotated into a recirculation position. Flushing channel passes through the sealing bushing and the wall of the housing.