US Patent 7487570 Apparatus for protecting motor of a vacuum cleaner

A motor protection apparatus for a vacuum cleaner includes: a motor chamber adapted to mount a motor; a penetration hole formed on a partition surrounding the motor chamber; a valve member configured to move between a first position closing the penetration hole and a second position at a distance from the penetration hole; and a casing adapted to be connected to an inner wall of the partition to surround the valve member and to guide movement of the valve member. A casing distance between an inner circumference of the casing and the valve member is minimized when the valve member is in the first position and maximized when the valve member is in the second position.