Patent Publication Number: US-6668421-B1

Title: Motor brush dust removing filter for use in vacuum cleaner

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a motor brush dust removing filter for use in a vacuum cleaner, and more particularly, to a motor brush dust filter for a vacuum cleaner in which brush dust from a brush assembly of an electric motor employed to generate suction power of the vacuum cleaner is prevented from being discharged. 
     2. Description of the Conventional Art 
     A typical vacuum cleaner, as shown in FIG. 1, includes a cylindrical canister  10 , a supporting member  11  having wheels  11   a  at a lower portion of cylindrical canister  10 , an air outlet  12   a  for discharging air at an upper portion of cylindrical canister  10 , and a vacuum generating unit  13  for sucking air into cylindrical canister  10 . 
     Vacuum generating unit  13  is made up of a vacuum chamber  13   a , a filter  13   b , an air suction fan  13   c  arranged on suction filter  13   b , and a motor  14  for driving air suction fan  13   c.    
     When an electric motor  14  is driven by power supplied thereto by a user, air suction fan  13   c  rotates so as to generate in a space of suction filter  13   b , i.e., vacuum chamber  13   a , a vacuum state. Then, debris is sucked in via a hose  13   d  by the suction force of vacuum chamber  13   a.    
     Thus, sucked-in substances are filtered by filter  13   b , and the air passed through filter  13   b  is discharged outside via air outlet  12   a.    
     Electric motor  14  employed for a rotation of air suction fan  13   c  is a common electric motor which uses a brush assembly  14   a  to provide a rotator with power. It is a common practice to place brush assembly  14   a  onto electric motor  14 , wherein brush assembly  14   a  has at top surface thereof an air vent  14   b  so that a heat generated from the friction of the brush may be cooled down and a brush dust may be discharged. 
     To prevent the brush dust generated by the operation of brush assembly  14   a  of motor  14  from being discharged out via air outlet  12   a , a conventional solution places a cover  15  having a non-woven fabric or a sponge  15   a  attached thereto over air vent  14   b , so that the brush dust can be roughly collected and caught by a non-woven fabric or a sponge  2   c  which is attached inside air outlet  12   a.    
     However, such a conventional brush dust collecting unit has disadvantages in that brush dust may not be completely blocked since cover  15  cannot be placed closely to air vent  14   b  considering cooling of inner heat generated by the operation of electric motor  4 . 
     SUMMARY OF THE INVENTION 
     Therefore, it is an object of the present invention to provide a motor brush dust removing filter for use in a vacuum cleaner in which the brush dust from a brush assembly of an electric motor may be discharged via an additional outlet and a filter is embedded in or attached to the outlet, to thereby allow an efficient cooling of the brush assembly and a complete blocking of the brush dust. 
     To accomplish the above object of the present invention, there is provided a motor brush dust removing filter for use in a vacuum cleaner, the vacuum cleaner including a cylindrical canister, a support member having wheels installed under the canister, an air outlet in a cover for discharging air from an upper portion of the canister, and a vacuum generating unit containing an electric motor for sucking air into the canister, wherein the cover has at a center thereof a circular aperture, a circular protrusion along the aperture, a filtering member, and a brush dust removing filter having a connection portion attached to a case of the motor brush assembly, so that brush dust discharged via an air vent formed at an upper surface of the brush assembly case is filtered by the filter of the filter unit and directly exhausted to the atmosphere. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will become more fully understood from the detailed description provided hereinafter with reference to the accompanying drawings, which are set forth by way of illustration only, and thus are not considered limitative of the present invention, and wherein: 
     FIG. 1 is a partial section view illustrating a conventional vacuum cleaner; 
     FIG. 2 is an enlarged section view illustrating the primary portion of the conventional vacuum cleaner; 
     FIG. 3 is a partial section view illustrating a configuration of a vacuum cleaner according to the present invention; 
     FIG. 4 is an enlarged section view illustrating the primary portion of the vacuum cleaner according to the present invention; and 
     FIG. 5 is a disassembled perspective view illustrating a filter adopted to the present invention. 
    
    
     PREFERRED EMBODIMENTS OF THE PRESENT INVENTION 
     The present invention will be explained more detail with reference to the attached drawings. 
     FIG. 3 is an overall section view of the vacuum cleaner of the present invention, FIG. 4 is a section view thereof, and FIG. 5 is an exploded or disassembled view of the filter unit of the present invention. 
     Similarly to the conventional machine, the vacuum cleaner of the present invention includes cylindrical canister  10  for having an inner space therein, a supporting member  11  which has wheels  11   a  and which is positioned at a lower portion of canister  10 , an air outlet  12   a  arranged at a cover in order to exhaust air from an upper portion of cylindrical canister  10 , and a vacuum generating unit  13  containing an electric motor  14  for sucking air into canister  10 . 
     A cover  12  is engaged to an upper portion of the cylindrical canister  10 . A circular aperture  12   b  and a circular protrusion or support shelf  12   c  are formed at the center of cover  12 , then a filter unit  2  is inserted through aperture  12   b  and engages protrusion  12   c  to rest thereon. 
     Filter unit  2  has a filter  2   a  in an upper interior portion thereof, and a connection portion  21  at a bottom surface of the filter. When connection portion  21  is connected to a brush assembly case  14   c  of a brush assembly  14   a  in cylindrical canister  10 , brush dust exhausted via an air vent  14   b  formed in an upper surface of brush assembly case  14   c  is filtered by filter  2   a  of filter unit  2  and directly discharged. 
     Filter unit  2  will be explained in more detail with reference to FIG.  5 . 
     Filter unit  2  includes a cylindrical lower case or casing  22  having a flange  22   a , an upper case or casing  23  having a plurality of spiral blades  23   a  which are arranged radially, a cover  24  on upper case  23 , and a connection portion  21  under lower case  22 . Filter  2   a  is inserted between upper case  23  and lower case  22 . 
     Connection portion  21  has an inverse L-shaped coupling slot  21   a , so that a fixation fin  14   d  formed on the brush assembly case of motor case  14   c  is fixed by being inserted into slot  21   a . Also, an additional filtering member  2   b  is inserted between the center of the interior of lower case  22  and the bottom surface of filter  2   a  for a filtering function enhancement. 
     The motor brush dust removing filter of the present invention removes brush dust generated by electric motor  14  when power is turned on in order to operate vacuum cleaner  1 , and an air suction fan  13   c  rotates in accordance with the driving of electric motor  14 , thereby obtaining vacuum suction force required for vacuum cleaning. 
     In brush assembly  14   a  of electric motor  14 , the brush which is adhered closely to a stator abrades the same during a driving of motor  4 . Brush dust which is generated by the abrasion of the brush is exhausted to an upper space of vacuum cleaner  1  via air vent  14   b  formed in an upper surface of brush assembly case  14   c.    
     In accordance with the present invention, cylinder-shaped connection portion  21  of filter unit  2  directly connects air vent  14   b  and filter unit  2 . Therefore, brush dust fed into filter unit  2  by filter  2   a , and only the purified air is exhausted to the outside or ambient atmosphere. 
     If filtering member  2   b  is arranged under filter  2   a , the brush dust is initially filtered by filtering member  2   b  and subsequently filtered by filter  2   a , thus achieving perfect filtering. 
     As described above, the motor brush dust removing filter of the present invention is advantageous in that a filter unit is arranged to discharge air through a cover, and heat generated by an electric motor can be directly and easily exhausted. As a result, overheating of the upper portion of the vacuum cleaner can be prevented, and a satisfactory filtering of brush dust is performed, only purified air being exhausted.