Rotary valve for air inlet to opening roller on an open-end spinning unit has air passage with straight-line flow when in open position

摘要

An open-end spinning unit is fitted with a rotary valve (19), which can alter the amount of air drawn in through an air inlet (18) to control the amount of air that is also drawn in through the trash opening (14). The air passage (21) in the valve is arranged so that, at least in the fully open position, the airflow is not diverted from its flow in the air inlet channel (18). The air passage (21) can be tapered or parallel. Alternatively it can be curved to make the valve less sensitive to angular adjustment in the partially closed position.