Vacuum cleaner and method of operating same

Abstract

A vacuum cleaner has a housing, a fan in the housing generating a suction air flow, an electric fan motor driving the fan, a dirt separator on the housing for separating dirt particles from the suction air flow, and a nozzle assembly. A suction pipe connects the housing to the nozzle assembly for drawing the suction air flow through the nozzle assembly. An external energy-storage unit on the suction pipe is connectable with the fan motor.

What is claimed is: 
     
         1 . A vacuum cleaner comprising
 a housing;   a fan in the housing generating a suction air flow;   an electric fan motor driving the fan;   a dirt separator on the housing for separating dirt particles from the suction air flow;   a nozzle assembly;   a suction pipe connecting the housing to the nozzle assembly for drawing the suction air flow through the nozzle assembly; and   an external energy-storage unit on the suction pipe and connectable with the fan motor.   
     
     
         2 . The vacuum cleaner according to  claim 1 , further comprising:
 an internal energy-storage unit in the housing for powering the fan motor.   
     
     
         3 . The vacuum cleaner according to  claim 1 , wherein the suction pipe is detachably connected with the external energy-storage unit or with the housing. 
     
     
         4 . The vacuum cleaner according to  claim 1 , further comprising:
 a main controller in the housing for operating the fan motor and thereby regulating the suction air stream by controlling energy supplied to the fan motor.   
     
     
         5 . The vacuum cleaner according to  claim 4 , further comprising:
 a charge controller in the external energy-storage unit; and   a data line connecting the charge controller to the main controller.   
     
     
         6 . The vacuum cleaner according to  claim 1 , further comprising:
 an electrically driven cleaning device on the nozzle assembly connectable or at least partially powered by the external energy-storage unit.   
     
     
         7 . A method for operating a vacuum cleaner according to  claim 1 , wherein the fan motor is at least partially powered by the external energy-storage unit. 
     
     
         8 . The method according to  claim 7 , wherein
 the external energy-storage unit has an external charge controller,   an internal energy-storage unit and internal charge controller are provided in the housing,   a main controller is provided in the housing and is connected to the external charge controller and to the internal charge controller for operating same.   
     
     
         9 . The method according to  claim 8 , wherein,
 in a first operating mode the external energy-storage unit is operated by the main controller to power the fan motor, and   in a second operating mode the internal energy-storage unit is operated by the main controller to power the fan motor.   
     
     
         10 . The method according to  claim 9 , wherein
 in a boost mode the external energy-storage unit and the internal storage unit are both operated by the main controller to power the fan motor.   
     
     
         11 . The method according to  claim 9 , wherein
 in a transfer mode the external energy-storage unit is operated by the main controller to charge the internal energy-storage unit.