Abstract:
A vacuum cleaner comprises a suction port assembly having a suction inlet, a rotatable drum, a driving pulley that drives the rotatable drum, a driven pulley that is driven by a motor and a free-wheeling idler pulley that can rotate irrespective of the driven pulley. A drive belt between the motor and the driven pulley can be moved off the driven pulley and onto the free-wheeling idler pulley. When the drive belt from the motor rides on the idler pulley, the rotatable drum is disconnected from the motor, allowing it to stop. The drive belt is move onto and off of the idler pulley by a user-operable two-position guide member. In a first position, the drive belt is connected to the driven pulley. In the second position, the drive belt is directed onto the free-wheeling idler pulley. A user of the vacuum cleaner can selectively activate and deactivate the rotatable drum during cleaning thereby saving power, reducing wear on the rotating drum and its bristles and reducing noise.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application claims the benefit of Korean Patent Application No. 2004-21061, filed Mar. 29, 2004, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.  
       FIELD OF THE INVENTION  
       [0002]     The present invention relates generally to a vacuum cleaner, and more particularly, to a suction port assembly comprising a rotatable drum mounted at a suction inlet, and a vacuum cleaner having the same.  
       BACKGROUND OF THE INVENTION  
       [0003]     A general vacuum cleaner includes therein a vacuum source such that, when the vacuum source is driven, the vacuum cleaner draws in contaminants using a suction force generated at a suction inlet, thereby cleaning a surface being cleaned. Recently, a rotatable drum is further provided to the vacuum cleaner for more complete cleaning of stubborn dust or dust on a surface difficult to be cleaned simply by the suction force. The rotatable drum is generally mounted adjacent to a suction inlet and provided with a plurality of brush members on an outer periphery thereof. When the rotatable drum is driven, the brush members are moved in contact with the surface being cleaned, thereby cleaning stubborn dust and dirt on surfaces such as carpet and bedclothes.  
         [0004]     However, as can be understood from the above, the rotatable drum is not always necessary. A vacuum cleaner that is capable of selectively using the rotatable drum according to the conditions of the surface being cleaned or the cleaning environment, would be an improvement over the prior art.  
       SUMMARY OF THE INVENTION  
       [0005]     An aspect of the present invention is to solve at least the above problems and/or disadvantages and to provide at least the advantages described below. Accordingly, an aspect of the present invention is to provide a suction port assembly capable of selectively driving a rotatable drum according to conditions of a surface being cleaned, and a vacuum cleaner comprising the same.  
         [0006]     In order to achieve the above-described aspects of the present invention, there is provided a vacuum cleaner body housing a vacuum source, a suction port on the vacuum cleaner body having a suction inlet for drawing in dust on a surface being cleaned and connected to the cleaner body such that the suction inlet is fluidly communicated with the cleaner body. A rotatable drum is mounted in the suction inlet to rotate by a driven pulley connected to the rotatable drum for power transmission. A free wheeling idler pulley that rotates without regard to the driven pulley. A driving source for supplying rotational power to the rotatable drum, drives a first drive belt for that can be selectively connected to either one of the driven pulley and the idler pulley. The first drive belt is moved from the driven pulley to the idler pulley by a guide member having a guide part that is moved between a first position and a second position, the first position being where the first drive belt is connected to the driven pulley and the second position being where the first drive belt is connected to the idler pulley. A cam member rotatably mounted to a suction port assembly having the suction inlet is moved to one of the first and the second positions by contact with the cam member to selectively drive the rotatable drum member.  
         [0007]     According to an embodiment of the present invention, the suction port assembly and the vacuum cleaner comprise a resilient spring member for elastically biasing the guide member toward any one of the first and the second positions.  
         [0008]     The resilient spring member is extended from the guide member and contacted by its free end with an inner wall of the suction port assembly body. The guide member and the resilient spring member are preferably formed from molded plastic.  
         [0009]     The suction port assembly and the vacuum cleaner further comprise a rotation knob, which includes a handle part rotatably mounted in a mounting hole of the suction port assembly body and exposed out of the suction port assembly body, and the cam member disposed in contact with the suction port assembly body. One of the mounting hole and the rotation knob comprises at least two fixing grooves, and the other one of the mounting hole and the rotation knob comprises a fixing projection elastically inserted in one of the at least two fixing grooves when the rotation knob is rotated to a predetermined position.  
         [0010]     The suction port assembly and the vacuum cleaner according to an embodiment of the present invention further comprise a middle shaft rotatably mounted between the rotatable drum and the driving source in the suction port assembly body and comprising the driven pulley and the idler pulley, and a second drive belt for connecting the middle shaft to the rotatable drum, and wherein, when the driven pulley is driven in connection with the first belt, the rotatable drum is driven by power transmitted through the second drive belt. The guide member is slidably mounted within the suction port assembly body to enable the guide part to move between the first and the second positions.  
         [0011]     The vacuum cleaner includes therein a driving source for generating a suction force in the suction inlet and further comprises a cleaner body pivotably connected to the suction port assembly body, a projection protruded from a portion of the cleaner body, the portion adjacent to the suction port assembly body, and an auxiliary guide member for moving the guide member, being moved by contact with the projection, when the cleaner body is pivoted and postured in a certain position with respect to the suction port assembly body.  
         [0012]     The auxiliary guide member comprises an auxiliary guide body slidably mounted within the suction port assembly body, and an auxiliary guide projection projected from a side of the auxiliary guide body to come into contact with the guide member when the cleaner body is postured in a certain position, thereby moving the guide part.  
         [0013]     Accordingly, when applying an embodiment of the present invention to an upright-type vacuum cleaner, the driving of the rotatable drum is automatically controlled according to posture of a cleaner body which is pivotably connected to the suction port assembly. 
     
    
     BRIEF DESCRIPTION OF THE DRAWING FIGURES  
       [0014]     The above aspect and other features of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawing figures, wherein;  
         [0015]      FIG. 1  is a perspective view of an exterior of a vacuum cleaner according to an embodiment of the present invention;  
         [0016]      FIG. 2  is a view schematically showing an inner structure of a suction port assembly of  FIG. 1 ; and  
         [0017]      FIGS. 3 and 4  are a perspective view and a bottom view, respectively, showing the operation of main parts of an embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0018]     Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawing figures.  
         [0019]     In the following description, reference numerals are used for the same elements even in different drawings. The matters defined in the description such as a detailed construction and elements are nothing but the ones provided to assist in a comprehensive understanding of the invention. Thus, it is apparent that the present invention can be carried out without those defined matters. Also, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.  
         [0020]      FIG. 1  shows an upright-type vacuum cleaner  100 . The vacuum cleaner  100  comprises a cleaner body  110  and a suction port assembly  150 .  
         [0021]     As shown in  FIG. 2 , the cleaner body  110  includes therein a vacuum source (not shown for brevity but well known to those of ordinary skill in the art) that is driven by a motor  120  and a dust-collecting chamber (not shown). The cleaner body  110  and the suction port assembly  150  are connected to each other such that a suction inlet  161  ( FIG. 2 ) formed at a bottom of the suction port assembly  150  fluidly communicates with the vacuum source and the dust-collecting chamber. As the vacuum source operates, it provides or generates a suction force at the suction inlet  161 . Dust on a surface being cleaned is thereby drawn into the collecting chamber with surrounding air by the suction force through the suction inlet  161 . The vacuum source may be mounted within the suction port assembly  150 .  
         [0022]     In the preferred embodiment, the suction port assembly  150 , as shown in  FIG. 2 , comprises an assembly body  160 , a rotatable drum  170 , a middle shaft  180 , a first drive belt  220 , a second second drive belt  220 , a guide member  190  and a rotation knob  200 . The rotatable drum  170  is mounted adjacent the suction inlet  161  and has several brush members  171  ( FIG. 3 ) on an outer periphery thereof. The rotatable drum  170  is driven by the rotational power of a driving source through one or more drive belts. For the driving source, a turbine (not shown) rotated by the air drawn into the cleaner body  110 , and the motor  120  used as the vacuum source may be adopted. In this embodiment, the motor  120  is adapted for the driving source.  
         [0023]     The driving motor  120  is mounted in the cleaner body  110  so that rotation of the motor&#39;s shaft  121  is exposed into the suction port assembly  150  when the cleaner body  110  is connected to the suction port assembly  150 . The driving motor  120  also functions to drive the vacuum source.  
         [0024]     As shown in  FIGS. 3 and 4 , the middle shaft  180  is rotatably mounted in the assembly body  160  between the rotatable drum  170  and the driving motor  120 . The middle shaft  180  comprises a driving pulley  182  that drives the rotatable drum  170  through a second second drive belt  220 . The assembly body  160  also includes a driven pulley  181 , so named because it is driven by rotational power supplied to it from the motor  120  through a first drive belt  220 . An idler pulley  183  lies alongside, i.e., adjacent to the driven pulley  181  so that the first drive belt  220  can be selectively directed to ride over either the driven pulley  181  or the idler pulley  183 . As shown in  FIG. 3 , all three of these pulleys  181 ,  182  and  183  rotate about the same axis, which coincides with the middle shaft  180  axis of rotation. Accordingly, the driving pulley  182  and the driven pulley  181  are driven by the motor  120  about the middle shaft  180 . The idler pulley  183  is mounted on the middle shaft  180  so that it can freely rotate about the middle shaft  180 . The idler pulley  183  is therefore considered to be “free wheeling” meaning that it can freely rotate about the middle shaft  180 , irrespective of the driving and the driven pulleys  181  and  182 . Rotation of the idler pulley  183  requires little or no energy, i.e., only the energy required to overcome frictional losses of the pulley&#39;s bearings.  
         [0025]     Depending on the position of the guide member  190 , the driven pulley  181  and the idler pulley  183  are selectively connected to the motor  120  through the first drive belt  220 . The driven pulley  181  and the driving pulley  181  are fixed to the middle shaft  180 , however, such that both pulleys  181  and  182  rotate together, through the middle shaft  180 . The second drive belt  220  therefore delivers power to the rotatable drum  170  from the driving pulley  182 , which is in turn driven by the middle shaft  180 . Since the driving pulley  182  and the driven pulley  181  are effectively locked to the middle shaft  180 , the driving pulley  182  is driven by the driven pulley  181 . The driven pulley  181  is in turn driven by the motor  120  through the first drive belt  220 . Power from the motor  120  can be removed from the driven pulley  181  and therefore removed from the rotatable drum  170  by moving the first drive belt  220  from the driven pulley  181  onto the idler pulley  183  instead. The first drive belt  220  is moved sideways to ride over the idler pulley  183  by movement of the guide member  190  in the direction of the arrow “A” as shown in  FIG. 3 .  
         [0026]     The guide member  190  translates as shown by the arrow “A” and directs the first drive belt  220  to run over either the driven pulley  181  or the idler pulley  183 . The guide member  190  includes a belt guide part  195  for restraining flank sides of the first drive belt  220 . The guide member  190  is slidably mounted in the assembly body  160  such that the guide part  195  is slid between a first position, where the first drive belt  220  and the driven pulley  181  are connected, and a second position, where the first drive belt  220  and the idler pulley  183  are connected, along a direction A of  FIG. 3 , as shown in  FIG. 1  and  FIG. 3 .  
         [0027]     A rotation knob  200  is provided on the top of the suction port assembly  150  for moving the guide member  190  according to a user&#39;s operation, so that the guide part  195  is placed in one of the aforementioned first and the second positions. To do this, the rotation knob  200  as shown in  FIG. 3  is rotatably mounted through a mounting hole  163  ( FIG. 1 ), which is formed through an upper surface of the assembly body  160 . The rotation knob  200  comprises a handle part  201  formed at an upper part thereof and exposed out of the assembly body  160 , and a cam member  205  formed at a lower part thereof and disposed in the assembly body  160 . The cam member  205  contacts with one side of the guide member  190  and has a non-circular transection. When the cam member  205  is rotated by operating the handle part  201 , the guide member  190  is moved by the contact with the cam member  205  in a manner that a first slide projection  165  slides along a slide slot  193 . By the movement of the guide member  190 , the first drive belt  220  is connected to one of the first driving pulley  181  and the idler pulley  183 .  
         [0028]     Although not illustrated, in an alternate embodiment the guide member  190  may be mounted to pivot about a pivot shaft (not shown).  
         [0029]     In another alternate embodiment not illustrated, the first driven  181  and the idler pulley  183  may be formed directly on the rotatable drum  170 . In this case, the structure of the suction port assembly  150  can be simplified by omitting the middle shaft  180 .  
         [0030]     When the rotation knob  200  moves the guide member  190 , the guide member  190  and the cam member  205  are preferably in constant contact with each other. A resilient spring member  191  is therefore provided in the preferred embodiment, that biases the guide member  190  against the cam member  205 . In the preferred embodiment, the resilient spring member  191  extends from one side of the guide member  190  to contact by a free end thereof, an inner wall of the assembly body  160  not shown in  FIG. 3 . The resilient spring member  191  may be integrally formed with the guide member  190 . The resilient spring member  191  is preferably formed by molding a synthetic resin.  
         [0031]     When rotation of the rotatable drum  170  is controlled by assistance of the resilient spring member  191 , as described above, noise and vibration can be caused by the first drive belt  220  as it rotates. To reduce noise and vibration, at least two fixing grooves  209  are formed on an outer circumference of the rotation knob  200 , and an fixing projection  169  is protruded from an inner circumference of the mounting hole  163  ( FIG. 1 ), which corresponds to the outer circumference of the rotation knob  200 . According to this structure, once the rotation knob  200  is rotated so that the fixing hole  209  is engaged with the fixing projection  169 , movement of the guide member  190  can be prevented until the rotation knob  200  is forcibly rotated by a user, thereby restraining noise and shiver.  
         [0032]     Application of the suction port assembly  150  shown in the figures is not limited to an upright-type vacuum cleaner  100 . Although not illustrated, a canister-type vacuum cleaner in which a suction port assembly is separately disposed from a cleaner body may employ the suction port assembly  150 , expecting the same function and effect.  
         [0033]     When the suction port assembly  150  is applied to the upright-type vacuum cleaner  100  according to an embodiment of the present invention, rotation of the rotatable drum  170  is controlled according to a posture of the cleaner body  110 . Especially when an auxiliary suction tool (not shown) is used instead of the suction port assembly  150  in a state that the suction port assembly  150  connected to the cleaner body  110 , noise from the rotatable drum  170  unnecessarily rotated in the suction port assembly  150  needs to be prevented. For this, the vacuum cleaner  100  of this embodiment comprises a projection  115  and an auxiliary guide member  210 . The projection  115  protruded on the main body  110  adjacent to the suction port assembly  150 . The auxiliary guide member  210  comprises an auxiliary guide body  211  mounted in the assembly body  160  to slide along a direction B of  FIG. 3 , and an auxiliary guide projection  215  projected from a side of the auxiliary guide body  211 . The auxiliary guide projection  215  engages and displaces the guide member  190  to move the belt  200  onto the idler pulley  183  when the cleaner body  110  is in a certain position with respect to the suction port assembly  150 . In a preferred embodiment, when the cleaner body  110  is upright with respect to the suction port assembly  150 , the auxiliary guide projection  215  is moved to contact and displace the guide member  190  as shown by arrow B. As the cleaner body  110  becomes upright, and when the suction port assembly  150  is therefore not in use, the auxiliary guide projection  215  gradually moves the guide member  190  until the first drive belt  220  is moved onto the idler pulley  183 .  
         [0034]     As can be appreciated from the above description of the vacuum cleaner  100  according to an embodiment of the present invention, driving of the rotatable drum  170  can be selected by a simple operation of the rotation knob  200 . Accordingly, the cleaning work can be adaptively performed according to conditions of the surfaces being cleaned.  
         [0035]     Especially in the upright-type vacuum cleaner applying an embodiment of the present invention, the driving of the rotatable drum  170  is automatically controlled according to the posture of the cleaner body  110 , thereby enabling a convenient cleaning work.  
         [0036]     While the invention has been shown and described with reference to certain embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.