Upright vacuum cleaner using return current of discharging air

Abstract

An upright vacuum cleaner includes a suction nozzle unit, an inlet formed on a bottom surface of the suction nozzle unit, an injection path disposed near the inlet, a suction motor mounted in the suction nozzle unit, and a main body attached to the suction nozzle unit and in fluid communication with the suction motor. The injection path ejects air toward a surface to be cleaned. The suction motor generates a suction force to draw in air and dust through the inlet. The main body separates dust from the air using centrifugal force, collects the dust, and discharges the air to the suction nozzle unit. The air discharged from the main body flows through the suction motor, is ejected from the injection path toward the surface to be cleaned, and is then suctioned into the inlet so that a portion of the discharged air circulates within the vacuum cleaner.

1 . An upright vacuum cleaner, comprising:
 a suction nozzle unit;   an inlet formed on a bottom surface of the suction nozzle unit;   an injection path disposed near the inlet, the injection path ejecting air toward a surface to be cleaned;   a suction motor mounted in the suction nozzle unit, the suction motor generating a suction force to draw in air and dust through the inlet; and   a main body coupled to the suction nozzle unit and in fluid communication with the suction motor, the main body configured to separate dust from the air drawn in through the inlet using a centrifugal force, collect the dust, and discharge the air to the suction nozzle unit;   wherein air discharged from the main body flows through the suction motor, is ejected from the suction nozzle unit through the injection path toward the surface to be cleaned, and is then suctioned into the inlet of the suction nozzle unit by the suction motor so that a portion of the discharged air circulates within the vacuum cleaner.   
   
   
       2 . The upright vacuum cleaner as claimed in  claim 1 , wherein the main body comprises:
 a frame, a lower end of which is hinged to the suction nozzle unit;   a grip disposed at an upper end of the frame; and   a dust collecting unit mounted at the frame.   
   
   
       3 . The upright vacuum cleaner as claimed in  claim 2 , wherein the dust collecting unit comprises:
 a cyclone part, the cyclone part having a substantially cylindrical shape;   an inflow port disposed at one side of the cyclone part to give a rotation force to the drawn-in air;   a dust bin detachably coupled to a lower side of the cyclone part, the dust bin collecting dust separated from the drawn-in air and descending from the cyclone unit due to gravity; and   an exhaust pipe penetrating a bottom surface of the dust bin and extending substantially vertically near the center of the dust bin, the exhaust pipe discharging the drawn-in air toward the suction nozzle unit.   
   
   
       4 . The upright vacuum cleaner as claimed in  claim 3 , further comprising a guide duct to fluidly communicate between the dust collecting unit and the suction nozzle unit is mounted inside the lower end of the frame which is hinged to the suction nozzle unit. 
   
   
       5 . The upright vacuum cleaner as claimed in  claim 4 , further comprising a first filter disposed between the exhaust pipe and the guide duct. 
   
   
       6 . The upright vacuum cleaner as claimed in  claim 1 , wherein the suction nozzle unit comprises:
 a housing;   a motor chamber disposed at the housing, the motor chamber receiving the suction motor;   a discharge path disposed at the housing in fluid communication with the injection path, the discharge path guiding air discharged from the motor chamber to a front of the housing; and   at least one injection hole formed at a terminal end of the injection path.   
   
   
       7 . The upright vacuum cleaner as claimed in  claim 6 , wherein the injection path is curved inwardly with a predetermined curvature toward the rear of the housing, so that the at least one injection hole is disposed toward the inlet. 
   
   
       8 . The upright vacuum cleaner as claimed in  claim 6 , wherein the suction nozzle unit further comprises a second filter disposed at the discharge path. 
   
   
       9 . The upright vacuum cleaner as claimed in  claim 6 , wherein the suction nozzle unit further comprises a rotating brush rotatably mounted inside the inlet and driven by the suction motor, the rotating brush striking dust attached to the surface to be cleaned and separating the dust from the surface to be cleaned while rotating. 
   
   
       10 . The upright vacuum cleaner as claimed in  claim 2 , further comprising an air re-intake passage in fluid communication with the dust collecting unit, the air re-intake passage receiving air discharged from the suction nozzle unit with air drawn-in containing dust on the surface to be cleaned, to the dust collecting unit. 
   
   
       11 . The upright vacuum cleaner as claimed in  claim 10 , wherein the air re-intake passage comprises:
 a first connection pipe with one end in fluid communication with the inlet of the suction nozzle unit;   a flexible hose with one end coupled to the first connection pipe, the flexible hose being disposed to the exterior of the suction nozzle unit; and   a second connection pipe with one end in fluid communication with the flexible hose and an opposite end in fluid communication with the dust collecting unit.   
   
   
       12 . An upright vacuum cleaner, comprising:
 means for receiving air and dust from a surface to be cleaned disposed in a suction nozzle unit;   means for generating a suction force to draw in the air and the dust, the means for generating a suction force being within the means for receiving air and dust;   means for separating the dust from the air disposed in a main body coupled to the suction nozzle unit;   means for collecting the dust disposed in the main body; and   means for discharging the air to the means for receiving air and dust so that a portion of the air recirculates through the upright vacuum cleaner.   
   
   
       13 . The upright vacuum cleaner as claimed in  claim 12 , wherein the means for separating the dust from the air includes means for forming a cyclone to separate the dust from the air by centrifugal force. 
   
   
       14 . The upright vacuum cleaner as claimed in  claim 12 , further comprising a first means for filtering air from the means for separating dust from the air. 
   
   
       15 . The upright vacuum cleaner as claimed in  claim 12 , wherein the means for receiving air and dust further comprising a second means for filtering air. 
   
   
       16 . The upright vacuum cleaner as claimed in  claim 12 , further comprising means for ejecting air toward the surface to be cleaned. 
   
   
       17 . The upright vacuum cleaner as claimed in  claim 12 , further comprising means for agitating dust. 
   
   
       18 . The upright vacuum cleaner as claimed in  claim 12 , further comprising means for guiding air from the means for receiving air and dust from a surface to be cleaned to the means for separating the dust from the air. 
   
   
       19 . An upright vacuum cleaner, comprising:
 a suction nozzle unit;   a suction motor mounted to the suction nozzle unit;   an inlet formed at a bottom surface of the suction nozzle unit;   at least one injection hole disposed near the inlet;   a main body coupled to the suction nozzle unit;   a cyclone disposed in the main body;   a first air flow path disposed between the inlet and the cyclone;   a dust bin detachably coupled to a lower side of the cyclone; and   a second air flow path disposed between the cyclone and the at least one injection hole,   wherein air and dust are received through the inlet, the dust is separated from the air at the cyclone, the air is discharged through the at least one injection hole, and a portion of the air recirculates through the upright vacuum cleaner.   
   
   
       20 . The upright vacuum cleaner as claimed in  claim 19 , further comprising at least one filter in the second air flow path.