Counting Discs

Koster counting discs are used to determine the number of papers or similar materials in a stack. Counting takes place from the top or bottom sheet of the stack, depending on the construction of the machine. By means of vacuum a corner or side edge of this sheet is sucked onto a rotating disc, thereby separated from the rest of the stack and then led to the back of the disc through a gap. While the sheet is inside the gap a signal is generated and thus the sheet is counted. The counting disc works its way sheet by sheet through the stack. Depending on the division of the disc there can be sucked in and counted up to 6 sheets during one turn.

For paper with different stiffness, grammage or material there are different counting discs, as a 30 g/m² paper requires another treatment than a 300 g/m² carton. Also the maximum counting speed depends on the material to be counted. With our machines and discs the counting speed can be more than 300 sheets per second which clearly sets us apart from other providers.

The usual area of application is security printing because here all the characteristics of this way of counting is demanded: Physical counting of every single sheet, speed, gentle on the paper, without leaving deformations or marks on the material. Due to the low depth of contact it is also possible to count banded products.