Patent ID: 7681327

Claim:
A vacuum belt conveyor of a web forming machine for transferring a threading tail, said vacuum belt conveyor comprising: an air-permeable belt loop; a frame, comprising two side plates; a first turning roll mounted to the frame between the two side plates, and having an axis defining an axial direction and a circumference defining a circumferential direction; a second turning roll mounted to the frame, and spaced from the first turning roll; wherein the first turning roll and the second turning roll are positioned within the belt loop and arranged so that the belt loop travels over the first turning roll and the second turning roll; wherein the first turning roll has portions defining an axial shaft with circular disc shaped necks thereon, the necks defining circumferential grooves therebetween; a vacuum chamber formed between the two side plates and containing the first turning roll, the vacuum chamber having a deflector forming part of the vacuum chamber, and a distributor pipe connected to a source of compressed air, the distributor pipe arranged to blow air over the deflector to form a source of vacuum which extends in the axial direction across the vacuum chamber which creates a vacuum effect in the vacuum chamber; at least one cross-directional dividing structure arranged to divide the vacuum chamber and the first turning roll to create at least a first vacuum zone and a second vacuum zone spaced in the axial direction along the first turning roll from the first vacuum zone, the source of vacuum arranged to create a vacuum effect in said first vacuum zone and said second vacuum zone; and wherein the distributor pipe is arranged to blow air over a second deflector mounted beneath the air-permeable belt loop to create a further vacuum zone on a section of the belt loop overlying the second deflector plate.