Vacuum cleaner

The invention relates to a vacuum cleaner having a suction nozzle, a suction object chamber and a fan which are fluidically connected to one another and fluidically connected to one another such that during a suction operation of the vacuum cleaner, a suction object is sucked into the suction object chamber by means of the fan via the suction nozzle, the suction substance chamber has a chamber housing defining a suction substance receiving region, the suction substance chamber has an emptying opening through which the suction substance can exit the suction substance chamber during the regeneration operation. The suction chamber has at least one thrust element (7) which can be reversibly moved into the suction receiving region (5) relative to the suction receiving region (5) and which is reversibly variable in size, said thrust element delimiting at least one partial region of the maximum volume of the suction receiving region (5) which can be used to receive the suction, the displacement and/or dimensional ch