Patent ID: 7603750

Claim:
An apparatus on a drafting system of a spinning machine for weighting a drafting system roller, comprising: a cylinder; a piston axially movable within the cylinder; a piston rod extending from the piston for applying weighting to the roller; an optical sensor positioned on one of the cylinder or the piston and configured to measure a distance between the sensor and a counter-surface on the other of the cylinder or the piston and produce a corresponding output signal; an evaluation device coupled to the output signal and producing a distance signal corresponding to a measured distance of the sensor from the counter-surface to determine a position of the piston and piston rod; and an electronic control and regulation device coupled to the sensor and configured to receive the distance signal, wherein the electronic control and evaluation device is adapted to compare the distance signal to stored predetermined maximum and minimum values relating to allowable lap formation on the roller and wear to the roller, respectively.