Hand held vacuum cleaners which are battery powered as well as powered by mains supply, are previously known, see for instance U.S. Pat. No. 4,967,443, and are used for fast cleaning of small surfaces. It is important that such vacuum cleaners are easily accessible and user friendly designed. These vacuum cleaners are usually designed such that the dust container together with the filter can be removed from the remaining part of the vacuum cleaner housing that contains the fan unit. In order to empty the vacuum cleaner also the filter has to be removed from the dust container before the content can be emptied through the opening which is established when the filter has been taken away. Removal of the dust from the dust container is hence troublesome, dirty and time consuming. It should in this connection be mentioned that the volume of the dust container for this type of vacuum cleaners is very limited and that the filter is rapidly clogged which means lost suction efficiency and that emptying has to be done with short intervals.
It is further known, see EP 914795, to provide a hand held vacuum cleaner of the type mentioned above with a large opening covered by a pivotable lid in order to facilitate emptying but since the dust usually gets stuck to the filter the dust can not be easily poured out of the opening. Moreover since the conventional filter system is quickly clogged the suction efficiency is still not sufficient.
It is also previously known to use the type of hand held vacuum cleaner described above in combination with a shaft part whose, lower portion supports a nozzle (so called stick cleaner), see for instance SE 9701543-2. The shaft part is provided with a tube connection by means of which dust laden air is transferred from the nozzle to the air inlet of the hand held vacuum cleaner which is removably secured to the shaft part. This means that the combined stick cleaner in a comfortable way can be used for floor cleaning purpose. Of course this type of vacuum cleaners also has the same disadvantages as the hand held vacuum cleaner described above with respect to filter clogging and handling when being emptied.
USPTO Backgrounds
USPTO Backgrounds