Vacuum cleaning device

A vacuum cleaning device comprising:

• a housing having a dirty air inlet and a clean air outlet and an airflow path between the dirty air inlet and the clean air outlet;
• a dust container mounted to the housing, wherein the airflow path goes through the dust container;
• a motor fan assembly mounted in the housing configured to create a negative pressure airflow along the airflow path in a suction mode and a positive pressure airflow along the airflow path in a blow mode;
• and
• a filter assembly mounted to the housing in the airflow path between the dust container and the motor-fan assembly, the filter assembly having a frame, a coarse filter element mounted to the frame and configured to stop relatively large dirt particles entrained in the negative pressure airflow during the suction mode, a fine filter element configured to stop relatively fine dirt particles entrained in the negative pressure airflow, and an airflow bypass directly attached to the frame and operated during the blow mode to enable the positive pressure airflow to flow through the airflow bypass and bypass the coarse filter element, wherein the relatively large dirt particles are larger than the fine dirt particles, and
• wherein, during the blow mode, the positive pressure airflow flows from the motor fan assembly, through the fine filter element, then through the airflow bypass, into the dust container, and out of the dirty air inlet, causing the fine dirt particles that are in a space between the fine filter element and the coarse filter element to bypass the coarse filter element and flow through the airflow bypass into the dust container and out of the dirty air inlet.