TECHNICAL FIELD 
     The present invention relates to a vacuum cleaner which can remove substances from the bottom by a rotary force of a brush and a vacuum pressure operated on a suction head by rotatably installing the brush on the suction head, and more particularly to, a vacuum cleaner which can consult a user&#39;s convenience by preferentially sucking thin and long substances such as hairs or furs of a pet dog not to be wound around the brush. 
     BACKGROUND ART 
     In general, a vacuum cleaner generates a suction force by a vacuum pressure, sucks the air and substances from the bottom, separates the air from the sucked substances, filters fine alien substances of the sucked air through various filters, and discharges the air. 
     The vacuum cleaners are classified into a cylindrical floor type vacuum cleaner, an upright type vacuum cleaner and a hand type vacuum cleaner by uses and using methods. The floor type vacuum cleaner can efficiently clean a hard bottom such as a wooden floor generally in a house, the upright type vacuum cleaner can efficiently clean a carpet, and the hand type vacuum cleaner can efficiently clean a narrow space such as stairs and desks. 
     The floor type or upright type vacuum cleaner includes a main body for generating a suction force, separating substances on a suction path, and filtering off fine alien substances of the sucked air such as dust, and a suction head or a suction nozzle unit linked to the main body, for contacting the bottom and sucking the substances and the ambient air. 
     In detail, the main body houses a suction motor for generating a suction force in a main body casing in which a suction path for the sucked air has been formed, and includes a filter assembly disposed higher than the suction motor in the sucked air flow direction, for filtering off fine alien substances of the suction flow such as dust. 
     Here, a suction tube linked to the suction head is connected to the lower region of the main body casing, and an exhaust unit having a plurality of holes for discharging the air passing through the suction motor and the filter assembly is formed at the rear upper region of the main body casing. 
     As shown in  FIG. 1 , the suction head is installed at the lower portion of the main body casing to be linked to the main body casing. A suction casing  2  having a suction hole  2   h  on its rectangular bottom surface for the inflow of the sucked air is installed to be linked to the suction tube I of the main body casing. A brush  4  adhered to an agitator is rotated on the suction hole  2   h  of the suction casing  2 , for pressurizing and agitating the inside of the carpet by the rotary force, floating dust hidden deep in the carpet, and sucking the substances from the bottom by a suction force by a vacuum pressure generated in the main body. If necessary, a plurality of bristles can be protruded from the brush  4  to easily clean the carpet. The structure of  FIG. 1  is one example of the upright vacuum cleaner. However, the floor type vacuum cleaner can have the same structure. That is, the agitator and the brush can be installed on the suction head, for pressurizing the bottom to facilitate suction of substances from the bottom. 
     Here, the brush  4  is positioned to cross the suction hole  2   h  of the suction casing  2  with its both ends hinge-coupled. One end of the brush  4  is connected to a driving motor (not shown) by various pulleys (not shown), so that the brush  4  can be rotatably driven. 
     Accordingly, when the suction motor is operated, the suction force is generated by the vacuum pressure, and thus the substances and the ambient air are sucked from the bottom through the suction hole  2   h  of the suction head. Here, when the driving motor is operated, the brush  4  is rotated to pressurize and agitate the bottom. The substances hidden deep in the carpet are floated or the substances adhered to the bottom are easily separated from the bottom, and sucked through the suction hole  2   h  with the sucked air. 
     The sucked air including the sucked substances flows through the suction tube I and the suction path and is separated from the substances. When the sucked air passes through the filter assembly, the fine alien substances of the sucked air such as dust are filtered off. Then, the air is discharged through the exhaust unit. 
     However, thin and long substances such as hair or fur of a pet dog exist on the bottom. In the conventional vacuum cleaner installing the brush on the agitator to improve cleaning efficiency, the thin and long substances are sucked through the suction hole by the vacuum pressure of the suction motor, transferred along the suction path, and wound around the rotating brush, instead of being separated from the sucked air with the other substances in the main body. The thin and long substances wound around the brush are not good for sanitation and appearance. Also, the thin and long substances reduce cleaning efficiency by deteriorating the function of the brush. Furthermore, it is difficult for the user to remove the thin and long substances wound around the brush. 
     DISCLOSURE OF THE INVENTION 
     The present invention is achieved to solve the above problems. An object of the present invention is to provide a vacuum cleaner which can make a brush clean and maintain performance of the brush, by sucking thin and long substances from the bottom before being wound around the brush, sending the substances to a suction path, and separating the substances with the other substances in a main body, when the brush for pressurizing and agitating the bottom by a rotary force is rotatably installed on a suction head for sucking the air including substances. 
     In order to achieve the above-described object of the invention, there is provided a vacuum cleaner, including: a suction head being installed at a front end of a suction path for sucking substances by a vacuum pressure generated by a suction motor, and having a suction hole for sucking the substances on its bottom; a brush installed on the suction hole of the suction head, and rotated to contact the bottom; and a hair tunnel formed on the suction head not to interfere with the brush, for preferentially sucking thin and long substances from the bottom. 
     The hair tunnel is linked to the front end of the suction path through a path isolated from the path for linking the suction hole to the front end of the suction path in the suction head. The inlet unit of the hair tunnel is installed to surround the suction hole, or installed at the front and/or rear portion of the suction hole in the general suction head progress direction. 
     A sweeper is installed at the inlet unit of the hair tunnel, for preferentially sucking the thin and long substances from the bottom to the hair tunnel. The sweeper includes a first sweeper partially downwardly protruded from the bottom surface of the end of the inlet unit of the hair tunnel far from the suction hole, and a second sweeper downwardly protruded from the bottom surface of the end of the inlet unit of the hair tunnel close to the suction hole. 
     In detail, the first and second sweepers are formed in a group bristle shape or comb-tooth shape with a predetermined width. The interval of the comb teeth of the second sweeper is smaller than that of the comb teeth of the first sweeper. The first and second sweepers can sweep the thin and long substances such as hairs or furs of a pet dog twice. 
     The comb teeth of the first sweeper are longer than those of the second sweeper to reduce a friction force with the bottom. Some of the comb teeth of the first sweeper include a support member for reducing an operation resistance by the first sweeper and obtaining a flow space of the sucked air. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will become better understood with reference to the accompanying drawings which are given only by way of illustration and thus are not limitative of the present invention, wherein: 
         FIG. 1  is a side-sectional view illustrating a suction head of a conventional upright vacuum cleaner; 
         FIG. 2  is a perspective view illustrating an upright vacuum cleaner in accordance with the present invention; 
         FIGS. 3 and 4  are a side-sectional view and a rear view illustrating a suction head of the upright vacuum cleaner of  FIG. 2 ; 
         FIG. 5  is a rear view illustrating another example of the suction head that can be applied to the upright vacuum cleaner of  FIG. 2 ; 
         FIGS. 6 and 7  are a perspective view and a side-sectional view illustrating first and second sweepers applied to hair tunnels of the upright vacuum cleaner of  FIG. 2 ; and 
         FIGS. 8A and 8B  are front views illustrating examples of the first and second sweepers of  FIG. 6 . 
     
    
    
     DETAILED DESCRIPTION 
     The preferred embodiments of the present invention achieving the above object will now be described in detail with reference to the accompanying drawings. 
     The preferred embodiments of the present invention will now be explained by exemplifying an upright vacuum cleaner. However, the scope of the present invention should not be limited to these preferred embodiments but to the claims as hereinafter recited. Especially, the present invention can be applied to different types of vacuum cleaners including the structure of the claims, such as floor type and hand type vacuum cleaners. 
     Referring to  FIG. 2 , the upright vacuum cleaner includes a main body  50  for generating a suction force and separating substances from sucked air, and a suction head  60  linked to the main body  50 , for sucking the sucked air. The suction head  60  is installed to individually suck thin and long substances such as hair or fur of a pet dog from the sucked air. 
     The main body  50  includes a main body casing  52  having a suction path inside, a filter assembly  54  installed on the suction path of the main body casing  52 , for filtering off substances of the sucked air such as dust, and a suction motor  56  installed on the suction path of the main body casing  52  at the rear end of the filter assembly  54 , for generating a suction force. 
     A suction tube I is installed at the lower region of the main body casing  52  to be connected to the suction path and linked to the suction head  60 . An exhaust unit  58  having a plurality of slit holes is formed at the rear upper region of the main body casing  52 , for discharging the air passing through the filter assembly  54 . 
     A handle  59  is upwardly extended from the higher region than the exhaust unit  58  in the main body casing  52 , and a control unit (not shown) for controlling the operation of the suction motor  56  is formed at one side of the main body casing  52 . 
     The suction motor  56  is formed in a cylindrical shape. When power is applied to the suction motor  56 , the fan is rotated to generate the suction force by the air pressure difference. The filter assembly  54  is detachably installed in the suction area, and the exhaust unit  58  of the main body casing  52  is linked to the discharge area. 
     Here, the filter assembly  54  includes various filter members for filtering off the substances of the air sucked to the suction motor  56 , such as dust hair and fur of a pet dog, or a dust collecting vessel for collecting the substances of the air in a cyclone method. 
     On the other hand, as illustrated in  FIGS. 3 and 4 , in the suction head  60 , a suction casing  62  is hinge-coupled to the lower portion of the main body casing  52 , a brush  64  is rotatably installed on a suction hole  62   h  formed on the bottom surface of the suction casing  62 , and a pair of hair tunnels  66  and  68  are formed on the suction hole  62   h  at both sides of the progress direction of the suction head  60 . The hair tunnels  66  and  68  are linked to the suction tube I of the main body casing  52 , for sucking the thin and long substances such as hair or fur of a pet dog individually from the suction hole  62   h.    
     The suction casing  62  has its top end linked to the suction tube I of the main body casing  52 , and is hinge-coupled to be freely moved. The rectangular suction hole  62   h  is formed long in the width direction on the bottom surface of the suction casing  62 . A suction path (not shown) is formed in the suction hole  62   h , for guiding the sucked air to the suction tube I of the main body casing  52 . 
     The brush  64  is positioned to cross the suction hole  62   h  with its both ends hinge-coupled. One end of the brush  64  is connected to a driving motor (not shown) by various pulleys (not shown) and rotatably driven. 
     Here, the brush  64  is formed in a cylindrical shape. Spiral bristles are protruded from the surface of the brush  64 . When the suction hole  62   h  is adhered to the bottom, the brush  64  pressurizes the bottom, facilitates suction of the substances hidden in the bottom such as dust, and generates a suction force. 
     Especially, the hair tunnels  66  and  68  are isolated from the path for linking the suction hole  62   h  to the front end of the suction tube I, and linked to the front end of the suction tube I of the main body casing  52  in the suction casing  62 , for generating the suction force inside. The inlet units  66   h  and  68   h  of the hair tunnels  66  and  68  are much smaller than the suction hole  62   h , for individually sucking the thin and long substances. 
     In detail, as shown in  FIG. 4 , when seen in the progress direction of the suction holes  62   h , the hair tunnels  66  and  68  can be two hair tunnels  66  and  68  having their inlet units  66   h  and  68   h  formed at the front and rear portions of the suction hole  62   h . Preferably, the inlet units  66   h  and  68   h  are formed in a slot hole shape long in the width direction at predetermined intervals from the suction hole  62   h.    
     It is also possible to form only one of the front hair tunnel  66  having its inlet unit  66   h  formed at the front portion of the suction hole  62   h  and the rear hair tunnel  68  having its inlet unit  68   h  formed at the rear portion of the suction hole  62   h.    
     Accordingly, when the suction head  60  moves forward to clean the bottom, the thin and long substances are sucked through the front hair tunnel  66 , and the other large substances are sucked through the suction hole  62   h . Conversely, when the suction head  60  moves backward to clean the bottom, the thin and long substances are sucked through the rear hair tunnel  68 , and the other large substances are sucked through the suction hole  62   h.    
     Although the substances are individually sucked through the hair tunnels  66  and  68  and the suction hole  62   h , the substances are collected at the front end of the suction tube I of the main body casing  52 , transferred through the suction tube I and the suction path of the main body casing  52 , and filtered off. 
     On the other hand, as shown in  FIG. 5 , the inlet unit  166   h  of the hair tunnel  166  can be formed to surround the suction hole  162   h . Preferably, the inlet unit  166   h  is formed in a polygonal ring shape with a predetermined interval from the circumference of the suction hole  162   h.    
     Therefore, when the suction head  60  moves in any one of the forward and backward and side directions to clean a surface, the thin and long substances are sucked through the hair tunnel  166 , and the other large substances are sucked through the suction hole  162   h . Such substances are transferred through the suction tube I and the suction path, and filtered off. 
     As described above, the thin and long substances, such as hair or fur of a pet dog, are sucked through the hair tunnels  66 ,  68  and  166  and the other substances are sucked through the suction hole  162   h . Even if the thin and long substances pass through the brush  64 , they are not wound around the brush  64 . As a result, the user does not have to clean the brush  64 . The appearance of the vacuum cleaner can also be improved. Because the substances are sucked through the hair tunnels  66 ,  68  and  166  and the suction hole  162   h  at the same time, the cleaning area can be widened and suction efficiency can be improved. 
     On the other hand, referring to  FIGS. 6 , and  7 , the suction head  60  of the vacuum cleaner includes first and second sweepers  66   a ,  66   b ,  68   a  and  68   b  at the front and rear ends of each hair tunnel  66  and  68 . The first and second sweepers  66   a ,  66   b ,  68   a  and  68   b  of the hair tunnels  66  and  68  are more protruded than the bottom surface of the suction casing  62  on which the inlet units  66   h  and  68   h  of the hair tunnels  66  and  68  have been formed. When the suction casing  62  moves closely to the bottom such as a carpet C, the first and second sweepers  66   a ,  66   b ,  68   a  and  68   b  are inserted into the bottom and transferred. Therefore, the thin and long substances hidden in the bottom are hooked on the first and second sweepers  66   a ,  6   b ,  68   a  and  68   b . The thin and long substances hooked on the first and second sweepers  66   a ,  66   b ,  68   a  and  68   b  are efficiently sucked through the adjacent inlet units  66   h  and  68   h  of the hair tunnels  66  and  68  by the suction force generated by the hair tunnels  66  and  68 . 
     The first and second sweepers  66   a ,  66   b ,  68   a  and  68   b  are downwardly protruded from the progress direction and the opposite direction of the hair tunnels  66  and  68 , respectively. In detail, the first and second sweepers  66   a  and  66   b  are formed at the front and rear ends of the front hair tunnel  66 , and the first and second sweepers  68   a  and  68   b  are formed at the rear and front ends of the rear hair tunnel  68 . 
     In addition, the first and second sweepers  66   a ,  66   b ,  68   a  and  68   b  can be irregularly downwardly protruded from the front and rear ends of the hair tunnels  66  and  68 , or formed in a group bristle shape or a comb shape having teeth at regular intervals. The first and second sweepers  66   a ,  66   b ,  68   a  and  68   b  will now be explained in more detail with reference to  FIGS. 8A and 8B . The interval a 1  between the comb teeth of the first sweepers  66   a  and  68   a  is relatively larger than the interval a 2  between the comb teeth of the second sweepers  66   b  and  68   b.    
     Accordingly, when the suction head  60  moves forward or backward to clean the bottom, the thin and long substances hidden in the bottom are firstly hooked on the relatively sparse comb teeth of the first sweepers  66   a  and  68   a , and the other thin and long substances are secondly hooked on the relatively dense comb teeth of the second sweepers  66   b  and  68   b . Because the thin and long substances are filtered off by the comb teeth of the first and second sweepers  66   a ,  66   b ,  68   a  and  68   b  twice and. sent to the adjacent hair tunnels  66  and  68 , the thin and long substances are not wound around the brush  64  through the suction hole  62   h.    
     In the case that the comb teeth of the first and second sweepers  66   a ,  66   b ,  68   a  and  68   b  are more densely formed, the friction force to the bottom increases. Accordingly, a large force is required to move the suction head  60 , and the air is not efficiently sucked between the comb teeth of the first and second sweepers  66   a ,  66   b ,  68   a  and  68   b , which reduces cleaning performance. In order to solve the foregoing problems, the length b 1  of the comb teeth of the first sweepers  66   a  and  68   a  is more lengthened than the length b 2  of the comb teeth of the second sweepers  66   b  and  68   b , and space obtaining support members  66   c  and  68   c  are downwardly protruded with a length shorter than the length of the first sweepers  66   a  and  68   a  between the first sweepers  66   a  and  68   a  and the hair tunnels  66  and  68 . The space obtaining support members  66   c  and  68   c  can be formed on some of the comb teeth of the first sweepers  66   a  and  68   a.    
     Because the ends of the comb teeth of the first sweepers  66   a  and  68   a  are inserted into the bottom such as the carpet C and the space obtaining support members  66   c  and  68   c  are supported on the bottom, the friction force decreases between the first sweepers  66   a  and  68   a  and the bottom. Thus, the suction head  60  can be easily transferred, and the suction flow can be increased by forming a suction space S for sucking the sucked air between the first sweepers  66   a  and  68   a  and the bottom, thereby improving cleaning performance. 
     The operation of the upright vacuum cleaner in accordance with the present invention will now be described. 
     When the suction head  60  moves forward to clean the bottom, if the suction hole  62   h  of the suction casing  62  is transferred closely to the bottom such as the carpet C, the first and second sweepers  66   a ,  66   a ,  68   a  and  68   b  are inserted into the bottom and transferred to hook the thin and long substances such as hair and a fur of a pet dog. The brush  64  is also transferred to pressurize the bottom. 
     Here, when the suction motor  56  is operated, the suction force is generated in the suction hole  62   h  and the hair tunnels  66  and  68 . Various substances hooked on the first sweeper  66   a  are sucked through the front hair tunnel  66 , and the other substances are hooked on the second sweeper  66   b  having denser comb teeth than the first sweeper  66   a  and sucked through the front hair tunnel  66 . Some substances are guided by the first and second sweepers  68   a  and  68   b  and sucked through the rear hair tunnel  68 . 
     In addition, the brush  64  is rotated to pressurize the bottom, and thus the substances hidden in the bottom such as dust are efficiently sucked through the suction hole  62   h.    
     Even if the ends of the comb teeth of the first sweepers  66   a  and  68   a  are inserted into the carpet C, since the space obtaining support members  66   c  and  68   c  are supported on the bottom, the sucked air is sucked to the suction space S and sucked through the front and rear hair tunnels  66  and  68  and the suction hole  62   h . That is, the suction area is relatively widened to improve cleaning performance. Because most of the thin and long substances are sucked through the front hair tunnel  66 , the other substances are sucked through the suction hole  62   h . It is thus possible to prevent the thin and long substances from being wound around the brush  64 . 
     As described above, various substances sucked through the front and rear hair tunnels  66  and  68  and the suction hole  62   h  are transferred through the suction tube I and the suction path of the main body casing  52 , filtered off through the dust collecting vessel and/or the filter assembly  54 , and externally discharged through the exhaust unit  58  via the suction motor  56 . 
     On the other hand, when the suction head  60  moves backward to clean the bottom by operating the suction motor  56 , various thin and long substances are guided by the first and second sweepers  68   a  and  68   b  in the rear hair tunnel  68  and filtered off in the same manner.
A vacuum cleaner is provided which can remove substances from a surface by a rotary force of a brush and a vacuum pressure operated on a suction head on which the brush is rotatably installed. The vacuum cleaner improves a user's convenience by preventing thin and long substances, such as hair or the fur of a pet dog, from being wound around the brush. The vacuum cleaner may include a suction head installed at a front end of a suction path, that sucks substances by a vacuum pressure generated by a suction motor and having a suction hole for sucking the substances, a brush installed in the suction hole and rotated to contact a surface, and a hair tunnel formed on the suction head so as not to interfere with the brush, that preferentially sucks thin and long substances from the surface.