Method and apparatus for determining the degree of filling of a dust collector of a dust collecting device, in particular a dust collector robot, and dust collection unit with such a device

A method for determining the degree of filling of a dust collector of a dust collecting device, in particular a dust collector robot, by means of at least a light emitting element and at least one light receiving element comprising the optical sensor whose output signals are evaluated, characterized in that the detection signals directly afferent in to the dust collecting container (SB) dust collecting channel ( SK) are determined and that the evaluation of the detection signals is effected by that the detection signals are counted and (with a definable degree of filling of the dust collecting SB) corresponding threshold value (SW) are compared, when reached or exceeded by the counted detection signals an alarm signal via the relevant degree of filling is dispensed.