Connecting tube having dust sensing function for use in vacuum cleaner

1. A connecting tube having a dust sensing function for use in a vacuum cleaner, comprising:

a tube element having a first air flowing passage therein to move suction air laden with dust or dirt;

a body connected to the tube element and having a second air flowing passage to communicate with the first air flowing passage;

a detecting sensor disposed in the second air flowing passage of the body to detect whether the dust or dirt passes through the second air flowing passage;

a lamp part to operate according to a signal outputted from the detecting sensor;

a rotating part rotatably disposed in the body;

a rotation driving-passage part disposed in the body to draw in an external air into the second air flowing passage from the outside by means of an air suction force in the second air flowing passage of the body and thus to rotate the rotating part;

an electric generator connected to the rotating part to rotate by the rotating part thus to generate an electric power for operating the detecting sensor and the lamp part;

a muffler part disposed in the body to reduce noises generating in rotating of the rotating part and in flowing of air in the second air flowing passage; and

a cover part to wrap an area of the body on which the detecting sensor, the lamp part, the rotation driving-passage part, the electric generator, and the muffler part are installed, wherein the muffler part comprises:

a plurality of resonating holes formed in the body adjacent to the second air flowing passage; and

a sponge filled in a space between the cover part and the body on the plurality of resonating holes.

2. The connecting tube of claim 1 , wherein the tube element comprises an element selected from the group consisting of a straight tube, a telescopic tube, and a flexible tube.

3. The connecting tube of claim 1 , wherein the body and the tube element are detachably disposed on a suction nozzle and an operating handle, or the operating handle and a cleaner body, respectively.

4. The connecting tube of claim 1 , wherein the detecting sensor comprises an optical sensor having a light-emitting part and a light-receiving part.

5. The connecting tube of claim 1 , wherein the lamp part comprises:

a first lamp to operate according to a first signal generated when the detecting sensor detects the dust or dirt; and

a second lamp to operate according to a second signal generated when the detecting sensor does not detect the dust or dirt.

6. The connecting tube of claim 1 , wherein the rotating part comprises an impeller having a rotating axis disposed parallel to a longitudinal axis of the second air flowing passage of the body.

7. The connecting tube of claim 1 , wherein the rotation driving-passage part comprises a rotating part-mounting part configured to mount the rotating part therein, and comprises a plurality of suction openings formed on an outer circumferential surface of the rotating part-mounting part to draw in the external air, a rotating part-mounting space in which the rotating part is disposed and through which the external air moves via the rotating part, and a discharging tube part formed on a surface of the rotating part-mounting part to communicate with the second air flowing passage.

8. The connecting tube of claim 1 , wherein the cover part comprises an upper cover and a lower cover, the upper cover wrapping the area of the body, the upper cover comprising a transparent plate and a plurality of air suction openings.