An arrangement for producing a spun thread includes a drafting unit having a delivery roller pair and an airjet assembly arranged downstream thereof. In the airjet assembly, a vortex chamber with an air evacuation channel is provided. Furthermore, at least one cleaning channel is provided, which is arranged with a suction opening to the delivery roller pair. This cleaning channel is connected by a mouthpiece to the air evacuation channel. A compressed air opening of an injector channel is located in the area of the mouthpiece. The injector channel increasing the low pressure of the air evacuation channel when required.